git.sesse.net Git - nageru/blob - nageru/mixer.cpp

   1 #undef Success
   2
   3 #include "mixer.h"
   4
   5 #include <assert.h>
   6 #include <epoxy/egl.h>
   7 #include <movit/effect.h>
   8 #include <movit/effect_chain.h>
   9 #include <movit/effect_util.h>
  10 #include <movit/flat_input.h>
  11 #include <movit/image_format.h>
  12 #include <movit/init.h>
  13 #include <movit/resource_pool.h>
  14 #include <pthread.h>
  15 #include <stdint.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <algorithm>
  19 #include <chrono>
  20 #include <condition_variable>
  21 #include <cstddef>
  22 #include <cstdint>
  23 #include <memory>
  24 #include <mutex>
  25 #include <ratio>
  26 #include <string>
  27 #include <thread>
  28 #include <utility>
  29 #include <vector>
  30
  31 #include "DeckLinkAPI.h"
  32 #include "LinuxCOM.h"
  33 #include "alsa_output.h"
  34 #include "basic_stats.h"
  35 #include "bmusb/bmusb.h"
  36 #include "bmusb/fake_capture.h"
  37 #ifdef HAVE_CEF
  38 #include "cef_capture.h"
  39 #endif
  40 #include "chroma_subsampler.h"
  41 #include "shared/context.h"
  42 #include "decklink_capture.h"
  43 #include "decklink_output.h"
  44 #include "decklink_util.h"
  45 #include "defs.h"
  46 #include "shared/disk_space_estimator.h"
  47 #include "ffmpeg_capture.h"
  48 #include "flags.h"
  49 #include "image_input.h"
  50 #include "input_mapping.h"
  51 #include "shared/metrics.h"
  52 #include "shared/va_display.h"
  53 #include "mjpeg_encoder.h"
  54 #include "pbo_frame_allocator.h"
  55 #include "shared/ref_counted_gl_sync.h"
  56 #include "resampling_queue.h"
  57 #include "shared/timebase.h"
  58 #include "timecode_renderer.h"
  59 #include "v210_converter.h"
  60 #include "video_encoder.h"
  61
  62 #undef Status
  63 #include <google/protobuf/util/json_util.h>
  64 #include "json.pb.h"
  65
  66 #ifdef HAVE_SRT
  67 // Must come after CEF, since it includes <syslog.h>, which has #defines
  68 // that conflict with CEF logging constants.
  69 #include <srt/srt.h>
  70 #endif
  71
  72 class IDeckLink;
  73 class QOpenGLContext;
  74
  75 using namespace movit;
  76 using namespace std;
  77 using namespace std::chrono;
  78 using namespace std::placeholders;
  79 using namespace bmusb;
  80
  81 Mixer *global_mixer = nullptr;
  82
  83 namespace {
  84
  85 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  86 {
  87         if (interlaced) {
  88                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  89                         input_state->buffered_frames[card_index][frame_num] =
  90                                 input_state->buffered_frames[card_index][frame_num - 1];
  91                 }
  92                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  93         } else {
  94                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  95                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  96                 }
  97         }
  98 }
  99
 100 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned cbcr_width, unsigned cbcr_height, unsigned v210_width)
 101 {
 102         bool first;
 103         switch (userdata->pixel_format) {
 104         case PixelFormat_10BitYCbCr:
 105                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
 106                 break;
 107         case PixelFormat_8BitYCbCr:
 108                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
 109                 break;
 110         case PixelFormat_8BitBGRA:
 111                 first = userdata->tex_rgba[field] == 0;
 112                 break;
 113         case PixelFormat_8BitYCbCrPlanar:
 114                 first = userdata->tex_y[field] == 0 || userdata->tex_cb[field] == 0 || userdata->tex_cr[field] == 0;
 115                 break;
 116         default:
 117                 assert(false);
 118         }
 119
 120         const bool recreate_main_texture =
 121                 first ||
 122                 width != userdata->last_width[field] ||
 123                 height != userdata->last_height[field] ||
 124                 cbcr_width != userdata->last_cbcr_width[field] ||
 125                 cbcr_height != userdata->last_cbcr_height[field];
 126         const bool recreate_v210_texture =
 127                 global_flags.bit_depth > 8 &&
 128                 (first || v210_width != userdata->last_v210_width[field] || height != userdata->last_height[field]);
 129
 130         if (recreate_main_texture) {
 131                 // We changed resolution since last use of this texture, so we need to create
 132                 // a new object. Note that this each card has its own PBOFrameAllocator,
 133                 // we don't need to worry about these flip-flopping between resolutions.
 134                 switch (userdata->pixel_format) {
 135                 case PixelFormat_10BitYCbCr:
 136                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
 137                         check_error();
 138                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 139                         check_error();
 140                         break;
 141                 case PixelFormat_8BitYCbCr: {
 142                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 143                         check_error();
 144                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 145                         check_error();
 146                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 147                         check_error();
 148                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 149                         check_error();
 150                         break;
 151                 }
 152                 case PixelFormat_8BitYCbCrPlanar: {
 153                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 154                         check_error();
 155                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 156                         check_error();
 157                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cb[field]);
 158                         check_error();
 159                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 160                         check_error();
 161                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cr[field]);
 162                         check_error();
 163                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 164                         check_error();
 165                         break;
 166                 }
 167                 case PixelFormat_8BitBGRA:
 168                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
 169                         check_error();
 170                         // NOTE: sRGB may be disabled by sRGBSwitchingFlatInput.
 171                         glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
 172                         check_error();
 173                         break;
 174                 default:
 175                         assert(false);
 176                 }
 177                 userdata->last_width[field] = width;
 178                 userdata->last_height[field] = height;
 179                 userdata->last_cbcr_width[field] = cbcr_width;
 180                 userdata->last_cbcr_height[field] = cbcr_height;
 181         }
 182         if (recreate_v210_texture) {
 183                 // Same as above; we need to recreate the texture.
 184                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
 185                 check_error();
 186                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 187                 check_error();
 188                 userdata->last_v210_width[field] = v210_width;
 189                 userdata->last_height[field] = height;
 190         }
 191 }
 192
 193 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
 194 {
 195         if (interlaced_stride) {
 196                 stride *= 2;
 197         }
 198         if (global_flags.flush_pbos) {
 199                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
 200                 check_error();
 201         }
 202
 203         glBindTexture(GL_TEXTURE_2D, tex);
 204         check_error();
 205         if (interlaced_stride) {
 206                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
 207                 check_error();
 208         } else {
 209                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 210                 check_error();
 211         }
 212
 213         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
 214         check_error();
 215         glBindTexture(GL_TEXTURE_2D, 0);
 216         check_error();
 217         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 218         check_error();
 219 }
 220
 221 }  // namespace
 222
 223 void JitterHistory::register_metrics(const vector<pair<string, string>> &labels)
 224 {
 225         global_metrics.add("input_underestimated_jitter_frames", labels, &metric_input_underestimated_jitter_frames);
 226         global_metrics.add("input_estimated_max_jitter_seconds", labels, &metric_input_estimated_max_jitter_seconds, Metrics::TYPE_GAUGE);
 227 }
 228
 229 void JitterHistory::unregister_metrics(const vector<pair<string, string>> &labels)
 230 {
 231         global_metrics.remove("input_underestimated_jitter_frames", labels);
 232         global_metrics.remove("input_estimated_max_jitter_seconds", labels);
 233 }
 234
 235 void JitterHistory::frame_arrived(steady_clock::time_point now, int64_t frame_duration, size_t dropped_frames)
 236 {
 237         if (frame_duration != last_duration) {
 238                 // If the frame rate changed, the input clock is also going to change,
 239                 // so our historical data doesn't make much sense anymore.
 240                 // Also, format changes typically introduce blips that are not representative
 241                 // of the typical frame stream. (We make the assumption that format changes
 242                 // don't happen all the time in regular use; if they did, we should probably
 243                 // rather keep the history so that we take jitter they may introduce into account.)
 244                 clear();
 245                 last_duration = frame_duration;
 246         }
 247         if (expected_timestamp > steady_clock::time_point::min()) {
 248                 expected_timestamp += dropped_frames * nanoseconds(frame_duration * 1000000000 / TIMEBASE);
 249                 double jitter_seconds = fabs(duration<double>(expected_timestamp - now).count());
 250                 history.push_back(orders.insert(jitter_seconds));
 251                 if (jitter_seconds > estimate_max_jitter()) {
 252                         ++metric_input_underestimated_jitter_frames;
 253                 }
 254
 255                 metric_input_estimated_max_jitter_seconds = estimate_max_jitter();
 256
 257                 if (history.size() > history_length) {
 258                         orders.erase(history.front());
 259                         history.pop_front();
 260                 }
 261                 assert(history.size() <= history_length);
 262         }
 263         expected_timestamp = now + nanoseconds(frame_duration * 1000000000 / TIMEBASE);
 264 }
 265
 266 double JitterHistory::estimate_max_jitter() const
 267 {
 268         if (orders.empty()) {
 269                 return 0.0;
 270         }
 271         size_t elem_idx = lrint((orders.size() - 1) * percentile);
 272         if (percentile <= 0.5) {
 273                 return *next(orders.begin(), elem_idx) * multiplier;
 274         } else {
 275                 return *prev(orders.end(), orders.size() - elem_idx) * multiplier;
 276         }
 277 }
 278
 279 void QueueLengthPolicy::register_metrics(const vector<pair<string, string>> &labels)
 280 {
 281         global_metrics.add("input_queue_safe_length_frames", labels, &metric_input_queue_safe_length_frames, Metrics::TYPE_GAUGE);
 282 }
 283
 284 void QueueLengthPolicy::unregister_metrics(const vector<pair<string, string>> &labels)
 285 {
 286         global_metrics.remove("input_queue_safe_length_frames", labels);
 287 }
 288
 289 void QueueLengthPolicy::update_policy(steady_clock::time_point now,
 290                                       steady_clock::time_point expected_next_input_frame,
 291                                       int64_t input_frame_duration,
 292                                       int64_t master_frame_duration,
 293                                       double max_input_card_jitter_seconds,
 294                                       double max_master_card_jitter_seconds)
 295 {
 296         double input_frame_duration_seconds = input_frame_duration / double(TIMEBASE);
 297         double master_frame_duration_seconds = master_frame_duration / double(TIMEBASE);
 298
 299         // Figure out when we can expect the next frame for this card, assuming
 300         // worst-case jitter (ie., the frame is maximally late).
 301         double seconds_until_next_frame = max(duration<double>(expected_next_input_frame - now).count() + max_input_card_jitter_seconds, 0.0);
 302
 303         // How many times are the master card expected to tick in that time?
 304         // We assume the master clock has worst-case jitter but not any rate
 305         // discrepancy, ie., it ticks as early as possible every time, but not
 306         // cumulatively.
 307         double frames_needed = (seconds_until_next_frame + max_master_card_jitter_seconds) / master_frame_duration_seconds;
 308
 309         // As a special case, if the master card ticks faster than the input card,
 310         // we expect the queue to drain by itself even without dropping. But if
 311         // the difference is small (e.g. 60 Hz master and 59.94 input), it would
 312         // go slowly enough that the effect wouldn't really be appreciable.
 313         // We account for this by looking at the situation five frames ahead,
 314         // assuming everything else is the same.
 315         double frames_allowed;
 316         if (master_frame_duration < input_frame_duration) {
 317                 frames_allowed = frames_needed + 5 * (input_frame_duration_seconds - master_frame_duration_seconds) / master_frame_duration_seconds;
 318         } else {
 319                 frames_allowed = frames_needed;
 320         }
 321
 322         safe_queue_length = max<int>(floor(frames_allowed), 0);
 323         metric_input_queue_safe_length_frames = safe_queue_length;
 324 }
 325
 326 Mixer::Mixer(const QSurfaceFormat &format)
 327         : httpd(),
 328           mixer_surface(create_surface(format)),
 329           h264_encoder_surface(create_surface(format)),
 330           decklink_output_surface(create_surface(format)),
 331           image_update_surface(create_surface(format))
 332 {
 333         memcpy(ycbcr_interpretation, global_flags.ycbcr_interpretation, sizeof(ycbcr_interpretation));
 334         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 335         check_error();
 336
 337         if (!epoxy_has_gl_extension("GL_EXT_texture_sRGB_decode") ||
 338             !epoxy_has_gl_extension("GL_ARB_sampler_objects")) {
 339                 fprintf(stderr, "Nageru requires GL_EXT_texture_sRGB_decode and GL_ARB_sampler_objects to run.\n");
 340                 exit(1);
 341         }
 342
 343         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 344         // will be halved when sampling them, and we need to compensate here.
 345         movit_texel_subpixel_precision /= 2.0;
 346
 347         resource_pool.reset(new ResourcePool);
 348         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 349                 output_channel[i].parent = this;
 350                 output_channel[i].channel = i;
 351         }
 352
 353         ImageFormat inout_format;
 354         inout_format.color_space = COLORSPACE_sRGB;
 355         inout_format.gamma_curve = GAMMA_sRGB;
 356
 357         // Matches the 4:2:0 format created by the main chain.
 358         YCbCrFormat ycbcr_format;
 359         ycbcr_format.chroma_subsampling_x = 2;
 360         ycbcr_format.chroma_subsampling_y = 2;
 361         if (global_flags.ycbcr_rec709_coefficients) {
 362                 ycbcr_format.luma_coefficients = YCBCR_REC_709;
 363         } else {
 364                 ycbcr_format.luma_coefficients = YCBCR_REC_601;
 365         }
 366         ycbcr_format.full_range = false;
 367         ycbcr_format.num_levels = 1 << global_flags.bit_depth;
 368         ycbcr_format.cb_x_position = 0.0f;
 369         ycbcr_format.cr_x_position = 0.0f;
 370         ycbcr_format.cb_y_position = 0.5f;
 371         ycbcr_format.cr_y_position = 0.5f;
 372
 373         // Initialize the neutral colors to sane values.
 374         for (unsigned i = 0; i < MAX_VIDEO_CARDS; ++i) {
 375                 last_received_neutral_color[i] = RGBTriplet(1.0f, 1.0f, 1.0f);
 376         }
 377
 378         // Display chain; shows the live output produced by the main chain (or rather, a copy of it).
 379         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
 380         check_error();
 381         GLenum type = global_flags.bit_depth > 8 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_BYTE;
 382         display_input = new YCbCrInput(inout_format, ycbcr_format, global_flags.width, global_flags.height, YCBCR_INPUT_SPLIT_Y_AND_CBCR, type);
 383         display_chain->add_input(display_input);
 384         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 385         display_chain->set_dither_bits(0);  // Don't bother.
 386         display_chain->finalize();
 387
 388         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, global_flags.width, global_flags.height, &httpd, global_disk_space_estimator));
 389         if (!global_flags.card_to_mjpeg_stream_export.empty()) {
 390                 mjpeg_encoder.reset(new MJPEGEncoder(&httpd, global_flags.va_display));
 391         }
 392
 393         // Must be instantiated after VideoEncoder has initialized global_flags.use_zerocopy.
 394         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get()));
 395
 396         // Must be instantiated after the theme, as the theme decides the number of FFmpeg inputs.
 397         std::vector<FFmpegCapture *> video_inputs = theme->get_video_inputs();
 398         audio_mixer.reset(new AudioMixer);
 399
 400         httpd.add_endpoint("/channels", bind(&Mixer::get_channels_json, this), HTTPD::ALLOW_ALL_ORIGINS);
 401         for (int channel_idx = 0; channel_idx < theme->get_num_channels(); ++channel_idx) {
 402                 char url[256];
 403                 snprintf(url, sizeof(url), "/channels/%d/color", channel_idx + 2);
 404                 httpd.add_endpoint(url, bind(&Mixer::get_channel_color_http, this, unsigned(channel_idx + 2)), HTTPD::ALLOW_ALL_ORIGINS);
 405         }
 406
 407         // Start listening for clients only once VideoEncoder has written its header, if any.
 408         httpd.start(global_flags.http_port);
 409
 410         // First try initializing the then PCI devices, then USB, then
 411         // fill up with fake cards until we have the desired number of cards.
 412         unsigned num_pci_devices = 0;
 413         unsigned card_index = 0;
 414
 415         {
 416                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 417                 if (decklink_iterator != nullptr) {
 418                         for ( ; card_index < unsigned(global_flags.max_num_cards); ++card_index) {
 419                                 IDeckLink *decklink;
 420                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 421                                         break;
 422                                 }
 423
 424                                 if (!decklink_card_is_active(decklink, card_index)) {
 425                                         fprintf(stderr, "DeckLink card %u is inactive in current profile, skipping (try changing it in Desktop Video Setup)\n", card_index);
 426                                         decklink->Release();
 427                                         continue;
 428                                 }
 429
 430                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
 431                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
 432                                 if (!output->set_device(decklink, capture->get_input())) {
 433                                         delete output;
 434                                         output = nullptr;
 435                                 }
 436                                 configure_card(card_index, capture, CardType::LIVE_CARD, output, /*is_srt_card=*/false);
 437                                 ++num_pci_devices;
 438                         }
 439                         decklink_iterator->Release();
 440                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 441                 } else {
 442                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 443                 }
 444         }
 445
 446         unsigned num_usb_devices = BMUSBCapture::num_cards();
 447         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < unsigned(global_flags.max_num_cards); ++usb_card_index, ++card_index) {
 448                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 449                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 450                 configure_card(card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr, /*is_srt_card=*/false);
 451         }
 452         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 453
 454         // Fill up with fake cards for as long as we can, so that the FFmpeg
 455         // and HTML cards always come last.
 456         unsigned num_fake_cards = 0;
 457 #ifdef HAVE_CEF
 458         size_t num_html_inputs = theme->get_html_inputs().size();
 459 #else
 460         size_t num_html_inputs = 0;
 461 #endif
 462         for ( ; card_index < MAX_VIDEO_CARDS - video_inputs.size() - num_html_inputs; ++card_index) {
 463                 // Only bother to activate fake capture cards to satisfy the minimum.
 464                 bool is_active = card_index < unsigned(global_flags.min_num_cards) || cards[card_index].force_active;
 465                 if (is_active) {
 466                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 467                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
 468                         ++num_fake_cards;
 469                 } else {
 470                         configure_card(card_index, nullptr, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
 471                 }
 472         }
 473
 474         if (num_fake_cards > 0) {
 475                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 476         }
 477
 478         // Initialize all video inputs the theme asked for.
 479         for (unsigned video_card_index = 0; video_card_index < video_inputs.size(); ++card_index, ++video_card_index) {
 480                 if (card_index >= MAX_VIDEO_CARDS) {
 481                         fprintf(stderr, "ERROR: Not enough card slots available for the videos the theme requested.\n");
 482                         abort();
 483                 }
 484                 configure_card(card_index, video_inputs[video_card_index], CardType::FFMPEG_INPUT, /*output=*/nullptr, /*is_srt_card=*/false);
 485                 video_inputs[video_card_index]->set_card_index(card_index);
 486         }
 487         num_video_inputs = video_inputs.size();
 488
 489 #ifdef HAVE_CEF
 490         // Same, for HTML inputs.
 491         std::vector<CEFCapture *> html_inputs = theme->get_html_inputs();
 492         for (unsigned html_card_index = 0; html_card_index < html_inputs.size(); ++card_index, ++html_card_index) {
 493                 if (card_index >= MAX_VIDEO_CARDS) {
 494                         fprintf(stderr, "ERROR: Not enough card slots available for the HTML inputs the theme requested.\n");
 495                         abort();
 496                 }
 497                 configure_card(card_index, html_inputs[html_card_index], CardType::CEF_INPUT, /*output=*/nullptr, /*is_srt_card=*/false);
 498                 html_inputs[html_card_index]->set_card_index(card_index);
 499         }
 500         num_html_inputs = html_inputs.size();
 501 #endif
 502
 503         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 504         BMUSBCapture::start_bm_thread();
 505
 506 #ifdef HAVE_SRT
 507         if (global_flags.srt_port >= 0) {
 508                 start_srt();
 509         }
 510 #endif
 511
 512         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
 513
 514         if (global_flags.bit_depth > 8) {
 515                 if (!v210Converter::has_hardware_support()) {
 516                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
 517                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 518                         abort();
 519                 }
 520                 v210_converter.reset(new v210Converter());
 521
 522                 // These are all the widths listed in the Blackmagic SDK documentation
 523                 // (section 2.7.3, “Display Modes”).
 524                 v210_converter->precompile_shader(720);
 525                 v210_converter->precompile_shader(1280);
 526                 v210_converter->precompile_shader(1920);
 527                 v210_converter->precompile_shader(2048);
 528                 v210_converter->precompile_shader(3840);
 529                 v210_converter->precompile_shader(4096);
 530         }
 531         if (global_flags.bit_depth > 8) {
 532                 if (!v210Converter::has_hardware_support()) {
 533                         fprintf(stderr, "ERROR: --ten-bit-output requires support for OpenGL compute shaders\n");
 534                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 535                         abort();
 536                 }
 537         }
 538
 539         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
 540         display_timecode_in_stream = global_flags.display_timecode_in_stream;
 541         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
 542
 543         if (global_flags.enable_alsa_output) {
 544                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 545         }
 546         output_card_is_master = global_flags.output_card_is_master;
 547         if (global_flags.output_card != -1) {
 548                 desired_output_card_index = global_flags.output_card;
 549                 set_output_card_internal(global_flags.output_card);
 550         }
 551
 552         output_jitter_history.register_metrics({{ "card", "output" }});
 553
 554         ImageInput::start_update_thread(image_update_surface);
 555 }
 556
 557 Mixer::~Mixer()
 558 {
 559         ImageInput::end_update_thread();
 560
 561         if (mjpeg_encoder != nullptr) {
 562                 mjpeg_encoder->stop();
 563         }
 564         httpd.stop();
 565         BMUSBCapture::stop_bm_thread();
 566
 567         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
 568                 if (cards[card_index].capture != nullptr) {  // Active.
 569                         cards[card_index].capture->stop_dequeue_thread();
 570                 }
 571                 if (cards[card_index].output) {
 572                         cards[card_index].output->end_output();
 573                         cards[card_index].output.reset();
 574                 }
 575         }
 576
 577         video_encoder.reset(nullptr);
 578 }
 579
 580 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, CardType card_type, DeckLinkOutput *output, bool is_srt_card)
 581 {
 582         bool is_active = capture != nullptr;
 583         if (is_active) {
 584                 printf("Configuring card %d...\n", card_index);
 585         } else {
 586                 assert(card_type == CardType::FAKE_CAPTURE);
 587         }
 588
 589         CaptureCard *card = &cards[card_index];
 590         if (card->capture != nullptr) {
 591                 card_mutex.unlock();  // The dequeue thread could be waiting for bm_frame().
 592                 card->capture->stop_dequeue_thread();
 593                 card_mutex.lock();
 594         }
 595         card->capture.reset(capture);
 596         card->is_fake_capture = (card_type == CardType::FAKE_CAPTURE);
 597         if (card->is_fake_capture) {
 598                 card->fake_capture_counter = fake_capture_counter++;
 599         }
 600         card->is_cef_capture = (card_type == CardType::CEF_INPUT);
 601         card->may_have_dropped_last_frame = false;
 602         card->type = card_type;
 603         if (card->output.get() != output) {
 604                 card->output.reset(output);
 605         }
 606
 607         PixelFormat pixel_format;
 608         if (card_type == CardType::FFMPEG_INPUT) {
 609                 pixel_format = capture->get_current_pixel_format();
 610         } else if (card_type == CardType::CEF_INPUT) {
 611                 pixel_format = PixelFormat_8BitBGRA;
 612         } else if (global_flags.bit_depth > 8) {
 613                 pixel_format = PixelFormat_10BitYCbCr;
 614         } else {
 615                 pixel_format = PixelFormat_8BitYCbCr;
 616         }
 617
 618         if (is_active) {
 619                 card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 620                 if (card->frame_allocator == nullptr) {
 621                         card->frame_allocator.reset(new PBOFrameAllocator(pixel_format, FRAME_SIZE, global_flags.width, global_flags.height, card_index, mjpeg_encoder.get()));
 622                 } else {
 623                         // The format could have changed, but we cannot reset the allocator
 624                         // and create a new one from scratch, since there may be allocated
 625                         // frames from it that expect to call release_frame() on it.
 626                         // Instead, ask the allocator to create new frames for us and discard
 627                         // any old ones as they come back. This takes the mutex while
 628                         // allocating, but nothing should really be sending frames in there
 629                         // right now anyway (start_bm_capture() has not been called yet).
 630                         card->frame_allocator->reconfigure(pixel_format, FRAME_SIZE, global_flags.width, global_flags.height, card_index, mjpeg_encoder.get());
 631                 }
 632                 card->capture->set_video_frame_allocator(card->frame_allocator.get());
 633                 if (card->surface == nullptr) {
 634                         card->surface = create_surface_with_same_format(mixer_surface);
 635                 }
 636                 while (!card->new_frames.empty()) card->new_frames.pop_front();
 637                 card->last_timecode = -1;
 638                 card->capture->set_pixel_format(pixel_format);
 639                 card->capture->configure_card();
 640
 641                 // NOTE: start_bm_capture() happens in thread_func().
 642         }
 643
 644         if (is_srt_card) {
 645                 assert(card_type == CardType::FFMPEG_INPUT);
 646         }
 647
 648         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 649         unsigned num_channels = card_type == CardType::LIVE_CARD ? 8 : 2;
 650         if (is_active) {
 651                 audio_mixer->set_device_parameters(device, card->capture->get_description(), card_type, num_channels, /*active=*/true);
 652         } else {
 653                 // Note: Keeps the previous name, if any.
 654                 char name[32];
 655                 snprintf(name, sizeof(name), "Fake card %u", card_index + 1);
 656                 audio_mixer->set_device_parameters(device, name, card_type, num_channels, /*active=*/false);
 657         }
 658         audio_mixer->reset_resampler(device);
 659         audio_mixer->trigger_state_changed_callback();
 660
 661         // Unregister old metrics, if any.
 662         if (!card->labels.empty()) {
 663                 const vector<pair<string, string>> &labels = card->labels;
 664                 card->jitter_history.unregister_metrics(labels);
 665                 card->queue_length_policy.unregister_metrics(labels);
 666                 global_metrics.remove_if_exists("input_received_frames", labels);
 667                 global_metrics.remove_if_exists("input_dropped_frames_jitter", labels);
 668                 global_metrics.remove_if_exists("input_dropped_frames_error", labels);
 669                 global_metrics.remove_if_exists("input_dropped_frames_resets", labels);
 670                 global_metrics.remove_if_exists("input_queue_length_frames", labels);
 671                 global_metrics.remove_if_exists("input_queue_duped_frames", labels);
 672
 673                 global_metrics.remove_if_exists("input_has_signal_bool", labels);
 674                 global_metrics.remove_if_exists("input_is_connected_bool", labels);
 675                 global_metrics.remove_if_exists("input_interlaced_bool", labels);
 676                 global_metrics.remove_if_exists("input_width_pixels", labels);
 677                 global_metrics.remove_if_exists("input_height_pixels", labels);
 678                 global_metrics.remove_if_exists("input_frame_rate_nom", labels);
 679                 global_metrics.remove_if_exists("input_frame_rate_den", labels);
 680                 global_metrics.remove_if_exists("input_sample_rate_hz", labels);
 681
 682                 card->srt_metrics.deinit(labels);
 683         }
 684
 685         if (is_active) {
 686                 // Register metrics.
 687                 vector<pair<string, string>> labels;
 688                 char card_name[64];
 689                 snprintf(card_name, sizeof(card_name), "%d", card_index);
 690                 labels.emplace_back("card", card_name);
 691
 692                 switch (card_type) {
 693                 case CardType::LIVE_CARD:
 694                         labels.emplace_back("cardtype", "live");
 695                         break;
 696                 case CardType::FAKE_CAPTURE:
 697                         labels.emplace_back("cardtype", "fake");
 698                         break;
 699                 case CardType::FFMPEG_INPUT:
 700                         if (is_srt_card) {
 701                                 labels.emplace_back("cardtype", "srt");
 702                         } else {
 703                                 labels.emplace_back("cardtype", "ffmpeg");
 704                         }
 705                         break;
 706                 case CardType::CEF_INPUT:
 707                         labels.emplace_back("cardtype", "cef");
 708                         break;
 709                 default:
 710                         assert(false);
 711                 }
 712                 card->jitter_history.register_metrics(labels);
 713                 card->queue_length_policy.register_metrics(labels);
 714                 global_metrics.add("input_received_frames", labels, &card->metric_input_received_frames);
 715                 global_metrics.add("input_dropped_frames_jitter", labels, &card->metric_input_dropped_frames_jitter);
 716                 global_metrics.add("input_dropped_frames_error", labels, &card->metric_input_dropped_frames_error);
 717                 global_metrics.add("input_dropped_frames_resets", labels, &card->metric_input_resets);
 718                 global_metrics.add("input_queue_length_frames", labels, &card->metric_input_queue_length_frames, Metrics::TYPE_GAUGE);
 719                 global_metrics.add("input_queue_duped_frames", labels, &card->metric_input_duped_frames);
 720
 721                 global_metrics.add("input_has_signal_bool", labels, &card->metric_input_has_signal_bool, Metrics::TYPE_GAUGE);
 722                 global_metrics.add("input_is_connected_bool", labels, &card->metric_input_is_connected_bool, Metrics::TYPE_GAUGE);
 723                 global_metrics.add("input_interlaced_bool", labels, &card->metric_input_interlaced_bool, Metrics::TYPE_GAUGE);
 724                 global_metrics.add("input_width_pixels", labels, &card->metric_input_width_pixels, Metrics::TYPE_GAUGE);
 725                 global_metrics.add("input_height_pixels", labels, &card->metric_input_height_pixels, Metrics::TYPE_GAUGE);
 726                 global_metrics.add("input_frame_rate_nom", labels, &card->metric_input_frame_rate_nom, Metrics::TYPE_GAUGE);
 727                 global_metrics.add("input_frame_rate_den", labels, &card->metric_input_frame_rate_den, Metrics::TYPE_GAUGE);
 728                 global_metrics.add("input_sample_rate_hz", labels, &card->metric_input_sample_rate_hz, Metrics::TYPE_GAUGE);
 729
 730                 if (is_srt_card) {
 731                         card->srt_metrics.init(labels);
 732                 }
 733
 734                 card->labels = labels;
 735         } else {
 736                 card->labels.clear();
 737         }
 738 }
 739
 740 void Mixer::set_output_card_internal(int card_index)
 741 {
 742         // We don't really need to take card_mutex, since we're in the mixer
 743         // thread and don't mess with any queues (which is the only thing that happens
 744         // from other threads), but it's probably the safest in the long run.
 745         unique_lock<mutex> lock(card_mutex);
 746         if (output_card_index != -1) {
 747                 // Switch the old card from output to input.
 748                 CaptureCard *old_card = &cards[output_card_index];
 749                 old_card->output->end_output();
 750
 751                 // Stop the fake card that we put into place.
 752                 // This needs to _not_ happen under the mutex, to avoid deadlock
 753                 // (delivering the last frame needs to take the mutex).
 754                 CaptureInterface *fake_capture = old_card->capture.get();
 755                 lock.unlock();
 756                 fake_capture->stop_dequeue_thread();
 757                 lock.lock();
 758                 old_card->capture = move(old_card->parked_capture);  // TODO: reset the metrics
 759                 old_card->is_fake_capture = false;
 760                 old_card->capture->start_bm_capture();
 761         }
 762         if (card_index != -1) {
 763                 CaptureCard *card = &cards[card_index];
 764                 CaptureInterface *capture = card->capture.get();
 765                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
 766                 // several seconds to complete (blocking on DisableVideoInput);
 767                 // see if we can maybe do it asynchronously.
 768                 lock.unlock();
 769                 capture->stop_dequeue_thread();
 770                 lock.lock();
 771                 card->parked_capture = move(card->capture);
 772                 CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 773                 configure_card(card_index, fake_capture, CardType::FAKE_CAPTURE, card->output.release(), /*is_srt_card=*/false);
 774                 card->jitter_history.clear();
 775                 card->capture->start_bm_capture();
 776                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
 777                 card->output->start_output(desired_output_video_mode, pts_int, /*is_master_card=*/output_card_is_master);
 778         }
 779         output_card_index = card_index;
 780         output_jitter_history.clear();
 781 }
 782
 783 namespace {
 784
 785 int unwrap_timecode(uint16_t current_wrapped, int last)
 786 {
 787         uint16_t last_wrapped = last & 0xffff;
 788         if (current_wrapped > last_wrapped) {
 789                 return (last & ~0xffff) | current_wrapped;
 790         } else {
 791                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 792         }
 793 }
 794
 795 }  // namespace
 796
 797 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 798                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 799                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 800 {
 801         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 802         CaptureCard *card = &cards[card_index];
 803
 804         ++card->metric_input_received_frames;
 805         card->metric_input_has_signal_bool = video_format.has_signal;
 806         card->metric_input_is_connected_bool = video_format.is_connected;
 807         card->metric_input_interlaced_bool = video_format.interlaced;
 808         card->metric_input_width_pixels = video_format.width;
 809         card->metric_input_height_pixels = video_format.height;
 810         card->metric_input_frame_rate_nom = video_format.frame_rate_nom;
 811         card->metric_input_frame_rate_den = video_format.frame_rate_den;
 812         card->metric_input_sample_rate_hz = audio_format.sample_rate;
 813
 814         if (is_mode_scanning[card_index]) {
 815                 if (video_format.has_signal) {
 816                         // Found a stable signal, so stop scanning.
 817                         is_mode_scanning[card_index] = false;
 818                 } else {
 819                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
 820                         steady_clock::time_point now = steady_clock::now();
 821                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 822                         if (sec_since_last_switch > switch_time_s) {
 823                                 // It isn't this mode; try the next one.
 824                                 mode_scanlist_index[card_index]++;
 825                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 826                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 827                                 last_mode_scan_change[card_index] = now;
 828                         }
 829                 }
 830         }
 831
 832         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 833         assert(frame_length > 0);
 834
 835         size_t num_samples = (audio_frame.len > audio_offset) ? (audio_frame.len - audio_offset) / audio_format.num_channels / (audio_format.bits_per_sample / 8) : 0;
 836         if (num_samples > OUTPUT_FREQUENCY / 10 && card->type != CardType::FFMPEG_INPUT) {
 837                 printf("%s: Dropping frame with implausible audio length (len=%d, offset=%d) [timecode=0x%04x video_len=%d video_offset=%d video_format=%x)\n",
 838                         description_for_card(card_index).c_str(), int(audio_frame.len), int(audio_offset),
 839                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 840                 if (video_frame.owner) {
 841                         video_frame.owner->release_frame(video_frame);
 842                 }
 843                 if (audio_frame.owner) {
 844                         audio_frame.owner->release_frame(audio_frame);
 845                 }
 846                 return;
 847         }
 848
 849         int dropped_frames = 0;
 850         if (card->last_timecode != -1) {
 851                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 852         }
 853
 854         // Number of samples per frame if we need to insert silence.
 855         // (Could be nonintegral, but resampling will save us then.)
 856         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 857
 858         if (dropped_frames > TYPICAL_FPS * 2) {
 859                 fprintf(stderr, "%s lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 860                         description_for_card(card_index).c_str(), card->last_timecode, timecode);
 861                 audio_mixer->reset_resampler(device);
 862                 dropped_frames = 0;
 863                 ++card->metric_input_resets;
 864         } else if (dropped_frames > 0) {
 865                 // Insert silence as needed.
 866                 fprintf(stderr, "%s dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 867                         description_for_card(card_index).c_str(), dropped_frames, timecode);
 868                 card->metric_input_dropped_frames_error += dropped_frames;
 869
 870                 bool success;
 871                 do {
 872                         success = audio_mixer->add_silence(device, silence_samples, dropped_frames);
 873                 } while (!success);
 874         }
 875
 876         if (num_samples > 0) {
 877                 audio_mixer->add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, audio_frame.received_timestamp);
 878
 879                 // Audio for the MJPEG stream. We don't resample; audio that's not in 48 kHz
 880                 // just gets dropped for now.
 881                 //
 882                 // Only bother doing MJPEG encoding if there are any connected clients
 883                 // that want the stream.
 884                 if (httpd.get_num_connected_multicam_clients() > 0 ||
 885                     httpd.get_num_connected_siphon_clients(card_index) > 0) {
 886                         vector<int32_t> converted_samples = convert_audio_to_fixed32(audio_frame.data + audio_offset, num_samples, audio_format, 2);
 887                         lock_guard<mutex> lock(card_mutex);
 888                         if (card->new_raw_audio.empty()) {
 889                                 card->new_raw_audio = move(converted_samples);
 890                         } else {
 891                                 // For raw audio, we don't really synchronize audio and video;
 892                                 // we just put the audio in frame by frame, and if a video frame is
 893                                 // dropped, we still keep the audio, which means it will be added
 894                                 // to the beginning of the next frame. It would probably be better
 895                                 // to move the audio pts earlier to show this, but most players can
 896                                 // live with some jitter, and in a lot of ways, it's much nicer for
 897                                 // Futatabi to have all audio locked to a video frame.
 898                                 card->new_raw_audio.insert(card->new_raw_audio.end(), converted_samples.begin(), converted_samples.end());
 899
 900                                 // Truncate to one second, just to be sure we don't have infinite buildup in case of weirdness.
 901                                 if (card->new_raw_audio.size() > OUTPUT_FREQUENCY * 2) {
 902                                         size_t excess_samples = card->new_raw_audio.size() - OUTPUT_FREQUENCY * 2;
 903                                         card->new_raw_audio.erase(card->new_raw_audio.begin(), card->new_raw_audio.begin() + excess_samples);
 904                                 }
 905                         }
 906                 }
 907         }
 908
 909         // Done with the audio, so release it.
 910         if (audio_frame.owner) {
 911                 audio_frame.owner->release_frame(audio_frame);
 912         }
 913
 914         card->last_timecode = timecode;
 915
 916         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 917         if (card->type == CardType::FFMPEG_INPUT && userdata != nullptr) {
 918                 FFmpegCapture *ffmpeg_capture = static_cast<FFmpegCapture *>(card->capture.get());
 919                 userdata->has_last_subtitle = ffmpeg_capture->get_has_last_subtitle();
 920                 userdata->last_subtitle = ffmpeg_capture->get_last_subtitle();
 921         }
 922 #ifdef HAVE_SRT
 923         if (card->type == CardType::FFMPEG_INPUT) {
 924                 int srt_sock = static_cast<FFmpegCapture *>(card->capture.get())->get_srt_sock();
 925                 if (srt_sock != -1) {
 926                         card->srt_metrics.update_srt_stats(srt_sock);
 927                 }
 928         }
 929 #endif
 930
 931         size_t y_offset, cbcr_offset;
 932         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
 933         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
 934                 // The calculation above is wrong for planar Y'CbCr, so just override it.
 935                 assert(card->type == CardType::FFMPEG_INPUT);
 936                 assert(video_offset == 0);
 937                 expected_length = video_frame.len;
 938
 939                 userdata->ycbcr_format = (static_cast<FFmpegCapture *>(card->capture.get()))->get_current_frame_ycbcr_format();
 940                 y_offset = 0;
 941                 cbcr_offset = video_format.width * video_format.height;
 942         } else {
 943                 // All the other Y'CbCr formats are 4:2:2.
 944                 y_offset = video_frame.size / 2 + video_offset / 2;
 945                 cbcr_offset = video_offset / 2;
 946         }
 947         if (video_frame.len - video_offset == 0 ||
 948             video_frame.len - video_offset != expected_length) {
 949                 if (video_frame.len != 0) {
 950                         printf("%s: Dropping video frame with wrong length (%zu; expected %zu)\n",
 951                                 description_for_card(card_index).c_str(), video_frame.len - video_offset, expected_length);
 952                 }
 953                 if (video_frame.owner) {
 954                         video_frame.owner->release_frame(video_frame);
 955                 }
 956
 957                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 958                 // so that pts can go up accordingly.
 959                 {
 960                         lock_guard<mutex> lock(card_mutex);
 961                         CaptureCard::NewFrame new_frame;
 962                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 963                         new_frame.length = frame_length;
 964                         new_frame.interlaced = false;
 965                         new_frame.dropped_frames = dropped_frames;
 966                         new_frame.received_timestamp = video_frame.received_timestamp;
 967                         card->new_frames.push_back(move(new_frame));
 968                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
 969                 }
 970                 card->new_frames_changed.notify_all();
 971                 return;
 972         }
 973
 974         unsigned num_fields = video_format.interlaced ? 2 : 1;
 975         steady_clock::time_point frame_upload_start;
 976         if (video_format.interlaced) {
 977                 // Send the two fields along as separate frames; the other side will need to add
 978                 // a deinterlacer to actually get this right.
 979                 assert(video_format.height % 2 == 0);
 980                 video_format.height /= 2;
 981                 assert(frame_length % 2 == 0);
 982                 frame_length /= 2;
 983                 num_fields = 2;
 984                 frame_upload_start = steady_clock::now();
 985         }
 986         assert(userdata != nullptr);
 987         userdata->last_interlaced = video_format.interlaced;
 988         userdata->last_has_signal = video_format.has_signal;
 989         userdata->last_is_connected = video_format.is_connected;
 990         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 991         userdata->last_frame_rate_den = video_format.frame_rate_den;
 992         RefCountedFrame frame(video_frame);
 993
 994         // Send the frames on to the main thread, which will upload and process htem.
 995         // It is entirely possible to upload them in the same thread (and it might even be
 996         // faster, depending on the GPU and driver), but it appears to be trickling
 997         // driver bugs very easily.
 998         //
 999         // Note that this means we must hold on to the actual frame data in <userdata>
1000         // until the upload is done, but we hold on to <frame> much longer than that
1001         // (in fact, all the way until we no longer use the texture in rendering).
1002         for (unsigned field = 0; field < num_fields; ++field) {
1003                 if (field == 1) {
1004                         // Don't upload the second field as fast as we can; wait until
1005                         // the field time has approximately passed. (Otherwise, we could
1006                         // get timing jitter against the other sources, and possibly also
1007                         // against the video display, although the latter is not as critical.)
1008                         // This requires our system clock to be reasonably close to the
1009                         // video clock, but that's not an unreasonable assumption.
1010                         steady_clock::time_point second_field_start = frame_upload_start +
1011                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
1012                         this_thread::sleep_until(second_field_start);
1013                 }
1014
1015                 {
1016                         lock_guard<mutex> lock(card_mutex);
1017                         CaptureCard::NewFrame new_frame;
1018                         new_frame.frame = frame;
1019                         new_frame.length = frame_length;
1020                         new_frame.field = field;
1021                         new_frame.interlaced = video_format.interlaced;
1022                         new_frame.dropped_frames = dropped_frames;
1023                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
1024                         new_frame.video_format = video_format;
1025                         new_frame.video_offset = video_offset;
1026                         new_frame.y_offset = y_offset;
1027                         new_frame.cbcr_offset = cbcr_offset;
1028                         new_frame.texture_uploaded = false;
1029                         if (card->type == CardType::FFMPEG_INPUT) {
1030                                 FFmpegCapture *ffmpeg_capture = static_cast<FFmpegCapture *>(card->capture.get());
1031                                 new_frame.neutral_color = ffmpeg_capture->get_last_neutral_color();
1032                         }
1033                         card->new_frames.push_back(move(new_frame));
1034                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
1035                         card->may_have_dropped_last_frame = false;
1036                 }
1037                 card->new_frames_changed.notify_all();
1038         }
1039 }
1040
1041 void Mixer::upload_texture_for_frame(
1042         int field, bmusb::VideoFormat video_format,
1043         size_t y_offset, size_t cbcr_offset, size_t video_offset, PBOFrameAllocator::Userdata *userdata)
1044 {
1045         size_t cbcr_width, cbcr_height;
1046         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
1047                 cbcr_width = video_format.width / userdata->ycbcr_format.chroma_subsampling_x;
1048                 cbcr_height = video_format.height / userdata->ycbcr_format.chroma_subsampling_y;
1049         } else {
1050                 // All the other Y'CbCr formats are 4:2:2.
1051                 cbcr_width = video_format.width / 2;
1052                 cbcr_height = video_format.height;
1053         }
1054
1055         bool interlaced_stride = video_format.interlaced && (video_format.second_field_start == 1);
1056         if (video_format.interlaced) {
1057                 cbcr_height /= 2;
1058         }
1059
1060         unsigned field_start_line;
1061         if (field == 1) {
1062                 field_start_line = video_format.second_field_start;
1063         } else {
1064                 field_start_line = video_format.extra_lines_top;
1065         }
1066
1067         // For anything not FRAME_FORMAT_YCBCR_10BIT, v210_width will be nonsensical but not used.
1068         size_t v210_width = video_format.stride / sizeof(uint32_t);
1069         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, cbcr_width, cbcr_height, v210_width);
1070
1071         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
1072         check_error();
1073
1074         switch (userdata->pixel_format) {
1075                 case PixelFormat_10BitYCbCr: {
1076                         size_t field_start = video_offset + video_format.stride * field_start_line;
1077                         upload_texture(userdata->tex_v210[field], v210_width, video_format.height, video_format.stride, interlaced_stride, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, field_start);
1078                         v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
1079                         break;
1080                 }
1081                 case PixelFormat_8BitYCbCr: {
1082                         size_t field_y_start = y_offset + video_format.width * field_start_line;
1083                         size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
1084
1085                         // Make up our own strides, since we are interleaving.
1086                         upload_texture(userdata->tex_y[field], video_format.width, video_format.height, video_format.width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_y_start);
1087                         upload_texture(userdata->tex_cbcr[field], cbcr_width, cbcr_height, cbcr_width * sizeof(uint16_t), interlaced_stride, GL_RG, GL_UNSIGNED_BYTE, field_cbcr_start);
1088                         break;
1089                 }
1090                 case PixelFormat_8BitYCbCrPlanar: {
1091                         assert(field_start_line == 0);  // We don't really support interlaced here.
1092                         size_t field_y_start = y_offset;
1093                         size_t field_cb_start = cbcr_offset;
1094                         size_t field_cr_start = cbcr_offset + cbcr_width * cbcr_height;
1095
1096                         // Make up our own strides, since we are interleaving.
1097                         upload_texture(userdata->tex_y[field], video_format.width, video_format.height, video_format.width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_y_start);
1098                         upload_texture(userdata->tex_cb[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cb_start);
1099                         upload_texture(userdata->tex_cr[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cr_start);
1100                         break;
1101                 }
1102                 case PixelFormat_8BitBGRA: {
1103                         size_t field_start = video_offset + video_format.stride * field_start_line;
1104                         upload_texture(userdata->tex_rgba[field], video_format.width, video_format.height, video_format.stride, interlaced_stride, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, field_start);
1105                         // These could be asked to deliver mipmaps at any time.
1106                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
1107                         check_error();
1108                         glGenerateMipmap(GL_TEXTURE_2D);
1109                         check_error();
1110                         glBindTexture(GL_TEXTURE_2D, 0);
1111                         check_error();
1112                         break;
1113                 }
1114                 default:
1115                         assert(false);
1116         }
1117
1118         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
1119         check_error();
1120 }
1121
1122 void Mixer::bm_hotplug_add(libusb_device *dev)
1123 {
1124         lock_guard<mutex> lock(hotplug_mutex);
1125         hotplugged_cards.push_back(dev);
1126 }
1127
1128 void Mixer::bm_hotplug_remove(unsigned card_index)
1129 {
1130         cards[card_index].new_frames_changed.notify_all();
1131 }
1132
1133 void Mixer::thread_func()
1134 {
1135         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
1136
1137         eglBindAPI(EGL_OPENGL_API);
1138         QOpenGLContext *context = create_context(mixer_surface);
1139         if (!make_current(context, mixer_surface)) {
1140                 printf("oops\n");
1141                 abort();
1142         }
1143
1144         // Start the actual capture. (We don't want to do it before we're actually ready
1145         // to process output frames.)
1146         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1147                 if (int(card_index) != output_card_index && cards[card_index].capture != nullptr) {
1148                         cards[card_index].capture->start_bm_capture();
1149                 }
1150         }
1151
1152         BasicStats basic_stats(/*verbose=*/true, /*use_opengl=*/true);
1153         int stats_dropped_frames = 0;
1154
1155         while (!should_quit) {
1156                 if (desired_output_card_index != output_card_index) {
1157                         set_output_card_internal(desired_output_card_index);
1158                 }
1159                 if (output_card_index != -1 &&
1160                     desired_output_video_mode != output_video_mode) {
1161                         DeckLinkOutput *output = cards[output_card_index].output.get();
1162                         output->end_output();
1163                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
1164                         output->start_output(desired_output_video_mode, pts_int, /*is_master_card=*/output_card_is_master);
1165                 }
1166
1167                 {
1168                         lock_guard<mutex> lock(card_mutex);
1169                         handle_hotplugged_cards();
1170                 }
1171
1172                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
1173                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
1174
1175                 bool master_card_is_output;
1176                 unsigned master_card_index;
1177                 if (output_card_index != -1 && output_card_is_master) {
1178                         master_card_is_output = true;
1179                         master_card_index = output_card_index;
1180                 } else {
1181                         master_card_is_output = false;
1182                         master_card_index = theme->map_signal_to_card(master_clock_channel);
1183                         assert(master_card_index < MAX_VIDEO_CARDS);
1184                 }
1185
1186                 vector<int32_t> raw_audio[MAX_VIDEO_CARDS];  // For MJPEG encoding.
1187                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame, raw_audio);
1188                 schedule_audio_resampling_tasks(output_frame_info.dropped_frames, output_frame_info.num_samples, output_frame_info.frame_duration, output_frame_info.is_preroll, output_frame_info.frame_timestamp);
1189                 stats_dropped_frames += output_frame_info.dropped_frames;
1190
1191                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1192                         if (card_index == master_card_index || !has_new_frame[card_index]) {
1193                                 continue;
1194                         }
1195                         if (new_frames[card_index].frame->len == 0) {
1196                                 ++new_frames[card_index].dropped_frames;
1197                         }
1198                         if (new_frames[card_index].dropped_frames > 0) {
1199                                 printf("%s dropped %d frames before this\n",
1200                                         description_for_card(card_index).c_str(), int(new_frames[card_index].dropped_frames));
1201                         }
1202                 }
1203
1204                 // If the first card is reporting a corrupted or otherwise dropped frame,
1205                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
1206                 if (!master_card_is_output &&
1207                     new_frames[master_card_index].frame != nullptr &&  // Timeout.
1208                     new_frames[master_card_index].frame->len == 0) {
1209                         ++stats_dropped_frames;
1210                         pts_int += new_frames[master_card_index].length;
1211                         continue;
1212                 }
1213
1214                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1215                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
1216                                 continue;
1217
1218                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
1219                         assert(new_frame->frame != nullptr);
1220                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
1221                         check_error();
1222
1223                         // The new texture might need uploading before use.
1224                         if (!new_frame->texture_uploaded) {
1225                                 upload_texture_for_frame(new_frame->field, new_frame->video_format, new_frame->y_offset, new_frame->cbcr_offset,
1226                                         new_frame->video_offset, (PBOFrameAllocator::Userdata *)new_frame->frame->userdata);
1227                                 new_frame->texture_uploaded = true;
1228                         }
1229
1230                         // Only set the white balance if it actually changed. This means that the user
1231                         // is free to override the white balance in a video with no white balance information
1232                         // actually set (ie. r=g=b=1 all the time), or one where the white point is wrong,
1233                         // but frame-to-frame decisions will be heeded. We do this pretty much as late
1234                         // as possible (ie., after picking out the frame from the buffer), so that we are sure
1235                         // that the change takes effect on exactly the right frame.
1236                         if (fabs(new_frame->neutral_color.r - last_received_neutral_color[card_index].r) > 1e-3 ||
1237                             fabs(new_frame->neutral_color.g - last_received_neutral_color[card_index].g) > 1e-3 ||
1238                             fabs(new_frame->neutral_color.b - last_received_neutral_color[card_index].b) > 1e-3) {
1239                                 theme->set_wb_for_card(card_index, new_frame->neutral_color.r, new_frame->neutral_color.g, new_frame->neutral_color.b);
1240                                 last_received_neutral_color[card_index] = new_frame->neutral_color;
1241                         }
1242
1243                         if (new_frame->frame->data_copy != nullptr && mjpeg_encoder->should_encode_mjpeg_for_card(card_index)) {
1244                                 RGBTriplet neutral_color = theme->get_white_balance_for_card(card_index);
1245                                 mjpeg_encoder->upload_frame(pts_int, card_index, new_frame->frame, new_frame->video_format, new_frame->y_offset, new_frame->cbcr_offset, move(raw_audio[card_index]), neutral_color);
1246                         }
1247
1248                 }
1249
1250                 int64_t frame_duration = output_frame_info.frame_duration;
1251                 render_one_frame(frame_duration);
1252                 {
1253                         lock_guard<mutex> lock(frame_num_mutex);
1254                         ++frame_num;
1255                 }
1256                 frame_num_updated.notify_all();
1257                 pts_int += frame_duration;
1258
1259                 basic_stats.update(frame_num, stats_dropped_frames);
1260                 // if (frame_num % 100 == 0) chain->print_phase_timing();
1261
1262                 if (should_cut.exchange(false)) {  // Test and clear.
1263                         video_encoder->do_cut(frame_num);
1264                 }
1265
1266 #if 0
1267                 // Reset every 100 frames, so that local variations in frame times
1268                 // (especially for the first few frames, when the shaders are
1269                 // compiled etc.) don't make it hard to measure for the entire
1270                 // remaining duration of the program.
1271                 if (frame == 10000) {
1272                         frame = 0;
1273                         start = now;
1274                 }
1275 #endif
1276                 check_error();
1277         }
1278
1279         resource_pool->clean_context();
1280 }
1281
1282 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
1283 {
1284         if (output_card_index != -1 && output_card_is_master) {
1285                 // The output card (ie., cards[output_card_index].output) is the master clock,
1286                 // so no input card (ie., cards[card_index].capture) is.
1287                 return false;
1288         }
1289         return (card_index == master_card_index);
1290 }
1291
1292 void Mixer::trim_queue(CaptureCard *card, size_t safe_queue_length)
1293 {
1294         // Count the number of frames in the queue, including any frames
1295         // we dropped. It's hard to know exactly how we should deal with
1296         // dropped (corrupted) input frames; they don't help our goal of
1297         // avoiding starvation, but they still add to the problem of latency.
1298         // Since dropped frames is going to mean a bump in the signal anyway,
1299         // we err on the side of having more stable latency instead.
1300         unsigned queue_length = 0;
1301         for (const CaptureCard::NewFrame &frame : card->new_frames) {
1302                 queue_length += frame.dropped_frames + 1;
1303         }
1304
1305         // If needed, drop frames until the queue is below the safe limit.
1306         // We prefer to drop from the head, because all else being equal,
1307         // we'd like more recent frames (less latency).
1308         unsigned dropped_frames = 0;
1309         while (queue_length > safe_queue_length) {
1310                 assert(!card->new_frames.empty());
1311                 assert(queue_length > card->new_frames.front().dropped_frames);
1312                 queue_length -= card->new_frames.front().dropped_frames;
1313
1314                 if (queue_length <= safe_queue_length) {
1315                         // No need to drop anything.
1316                         break;
1317                 }
1318
1319                 card->new_frames.pop_front();
1320                 card->new_frames_changed.notify_all();
1321                 --queue_length;
1322                 ++dropped_frames;
1323
1324                 if (queue_length == 0 && card->is_cef_capture) {
1325                         card->may_have_dropped_last_frame = true;
1326                 }
1327         }
1328
1329         card->metric_input_dropped_frames_jitter += dropped_frames;
1330         card->metric_input_queue_length_frames = queue_length;
1331
1332 #if 0
1333         if (dropped_frames > 0) {
1334                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
1335                         card_index, dropped_frames);
1336         }
1337 #endif
1338 }
1339
1340 pair<string, string> Mixer::get_channels_json()
1341 {
1342         Channels ret;
1343         for (int channel_idx = 0; channel_idx < theme->get_num_channels(); ++channel_idx) {
1344                 Channel *channel = ret.add_channel();
1345                 channel->set_index(channel_idx + 2);
1346                 channel->set_name(theme->get_channel_name(channel_idx + 2));
1347                 channel->set_color(theme->get_channel_color(channel_idx + 2));
1348         }
1349         string contents;
1350         google::protobuf::util::MessageToJsonString(ret, &contents);  // Ignore any errors.
1351         return make_pair(contents, "text/json");
1352 }
1353
1354 pair<string, string> Mixer::get_channel_color_http(unsigned channel_idx)
1355 {
1356         return make_pair(theme->get_channel_color(channel_idx), "text/plain");
1357 }
1358
1359 Mixer::OutputFrameInfo Mixer::get_one_frame_from_each_card(unsigned master_card_index, bool master_card_is_output, CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS], bool has_new_frame[MAX_VIDEO_CARDS], vector<int32_t> raw_audio[MAX_VIDEO_CARDS])
1360 {
1361         OutputFrameInfo output_frame_info;
1362         constexpr steady_clock::duration master_card_timeout = milliseconds(200);
1363 start:
1364         unique_lock<mutex> lock(card_mutex, defer_lock);
1365         bool timed_out = false;
1366         if (master_card_is_output) {
1367                 // Clocked to the output, so wait for it to be ready for the next frame.
1368                 cards[master_card_index].output->wait_for_frame(pts_int, &output_frame_info.dropped_frames, &output_frame_info.frame_duration, &output_frame_info.is_preroll, &output_frame_info.frame_timestamp);
1369                 lock.lock();
1370         } else {
1371                 // Wait for the master card to have a new frame.
1372                 output_frame_info.is_preroll = false;
1373                 lock.lock();
1374                 timed_out = !cards[master_card_index].new_frames_changed.wait_for(lock,
1375                         master_card_timeout,
1376                         [this, master_card_index] {
1377                                 return !cards[master_card_index].new_frames.empty() ||
1378                                         cards[master_card_index].capture == nullptr ||
1379                                         cards[master_card_index].capture->get_disconnected();
1380                         });
1381                 if (timed_out) {
1382                         fprintf(stderr, "WARNING: Master card (%s) did not deliver a frame for %u ms, creating a fake one.\n",
1383                                 description_for_card(master_card_index).c_str(),
1384                                 unsigned(duration_cast<milliseconds>(master_card_timeout).count()));
1385                 }
1386         }
1387
1388         if (timed_out) {
1389                 // The master card stalled for 200 ms (possible when it's e.g.
1390                 // an SRT card). Send a frame no matter what; this also makes sure
1391                 // any other cards get to empty their queues, and in general,
1392                 // that we make _some_ sort of forward progress.
1393                 handle_hotplugged_cards();
1394         } else if (master_card_is_output) {
1395                 handle_hotplugged_cards();
1396         } else if (cards[master_card_index].new_frames.empty()) {
1397                 // We were woken up, but not due to a new frame. Deal with it
1398                 // and then restart.
1399                 assert(cards[master_card_index].capture == nullptr ||
1400                        cards[master_card_index].capture->get_disconnected());
1401                 handle_hotplugged_cards();
1402                 lock.unlock();
1403                 goto start;
1404         }
1405
1406         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1407                 CaptureCard *card = &cards[card_index];
1408                 if (card->new_frames.empty()) {  // Starvation.
1409                         ++card->metric_input_duped_frames;
1410 #ifdef HAVE_CEF
1411                         if (card->is_cef_capture && card->may_have_dropped_last_frame) {
1412                                 // Unlike other sources, CEF is not guaranteed to send us a steady
1413                                 // stream of frames, so we'll have to ask it to repaint the frame
1414                                 // we dropped. (may_have_dropped_last_frame is set whenever we
1415                                 // trim the queue completely away, and cleared when we actually
1416                                 // get a new frame.)
1417                                 ((CEFCapture *)card->capture.get())->request_new_frame(/*ignore_if_locked=*/true);
1418                         }
1419 #endif
1420                 } else {
1421                         new_frames[card_index] = move(card->new_frames.front());
1422                         has_new_frame[card_index] = true;
1423                         card->new_frames.pop_front();
1424                         card->new_frames_changed.notify_all();
1425                 }
1426
1427                 raw_audio[card_index] = move(card->new_raw_audio);
1428         }
1429
1430         if (timed_out) {
1431                 // Pretend the frame happened a while ago and was only processed now,
1432                 // so that we get the duration sort-of right. This isn't ideal.
1433                 output_frame_info.dropped_frames = 0;  // Hard to define, really.
1434                 output_frame_info.frame_duration = lrint(TIMEBASE * duration<double>(master_card_timeout).count());
1435                 output_frame_info.frame_timestamp = steady_clock::now() - master_card_timeout;
1436         } else if (!master_card_is_output) {
1437                 output_frame_info.frame_timestamp = new_frames[master_card_index].received_timestamp;
1438                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
1439                 output_frame_info.frame_duration = new_frames[master_card_index].length;
1440         }
1441
1442         if (!output_frame_info.is_preroll) {
1443                 output_jitter_history.frame_arrived(output_frame_info.frame_timestamp, output_frame_info.frame_duration, output_frame_info.dropped_frames);
1444         }
1445
1446         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1447                 CaptureCard *card = &cards[card_index];
1448                 if (has_new_frame[card_index] &&
1449                     !input_card_is_master_clock(card_index, master_card_index) &&
1450                     !output_frame_info.is_preroll) {
1451                         card->queue_length_policy.update_policy(
1452                                 output_frame_info.frame_timestamp,
1453                                 card->jitter_history.get_expected_next_frame(),
1454                                 new_frames[master_card_index].length,
1455                                 output_frame_info.frame_duration,
1456                                 card->jitter_history.estimate_max_jitter(),
1457                                 output_jitter_history.estimate_max_jitter());
1458                         trim_queue(card, min<int>(global_flags.max_input_queue_frames,
1459                                                   card->queue_length_policy.get_safe_queue_length()));
1460                 }
1461         }
1462
1463         // This might get off by a fractional sample when changing master card
1464         // between ones with different frame rates, but that's fine.
1465         int64_t num_samples_times_timebase = int64_t(OUTPUT_FREQUENCY) * output_frame_info.frame_duration + fractional_samples;
1466         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
1467         fractional_samples = num_samples_times_timebase % TIMEBASE;
1468         assert(output_frame_info.num_samples >= 0);
1469
1470         if (timed_out) {
1471                 DeviceSpec device{InputSourceType::CAPTURE_CARD, master_card_index};
1472                 bool success;
1473                 do {
1474                         success = audio_mixer->add_silence(device, output_frame_info.num_samples, /*dropped_frames=*/0);
1475                 } while (!success);
1476         }
1477
1478         return output_frame_info;
1479 }
1480
1481 void Mixer::handle_hotplugged_cards()
1482 {
1483         // Check for cards that have been disconnected since last frame.
1484         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1485                 CaptureCard *card = &cards[card_index];
1486                 if (card->capture != nullptr && card->capture->get_disconnected()) {
1487                         bool is_active = card_index < unsigned(global_flags.min_num_cards) || cards[card_index].force_active;
1488                         if (is_active) {
1489                                 fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
1490                                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1491                                 configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
1492                                 card->jitter_history.clear();
1493                                 card->capture->start_bm_capture();
1494                         } else {
1495                                 // NOTE: The theme might end up forcing the card back at some later point
1496                                 // (ie., force_active is false now, but might immediately be true again on
1497                                 // e.g. the next frame). That should be rare, though, so we don't bother
1498                                 // adjusting the message.
1499                                 fprintf(stderr, "Card %u went away, removing. (To keep a fake card, increase --num-cards.)\n", card_index);
1500                                 theme->remove_card(card_index);
1501                                 configure_card(card_index, /*capture=*/nullptr, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
1502                                 card->jitter_history.clear();
1503                         }
1504                 }
1505         }
1506
1507         // Count how many active cards we already have. Used below to check that we
1508         // don't go past the max_cards limit set by the user. Note that (non-SRT) video
1509         // and HTML “cards” don't count towards this limit.
1510         int num_video_cards = 0;
1511         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1512                 CaptureCard *card = &cards[card_index];
1513                 if (card->type == CardType::LIVE_CARD || is_srt_card(card)) {
1514                         ++num_video_cards;
1515                 }
1516         }
1517
1518         // Check for cards that have been connected since last frame.
1519         vector<libusb_device *> hotplugged_cards_copy;
1520 #ifdef HAVE_SRT
1521         vector<int> hotplugged_srt_cards_copy;
1522 #endif
1523         {
1524                 lock_guard<mutex> lock(hotplug_mutex);
1525                 swap(hotplugged_cards, hotplugged_cards_copy);
1526 #ifdef HAVE_SRT
1527                 swap(hotplugged_srt_cards, hotplugged_srt_cards_copy);
1528 #endif
1529         }
1530         for (libusb_device *new_dev : hotplugged_cards_copy) {
1531                 // Look for a fake capture card where we can stick this in.
1532                 int free_card_index = -1;
1533                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1534                         if (cards[card_index].is_fake_capture) {
1535                                 free_card_index = card_index;
1536                                 break;
1537                         }
1538                 }
1539
1540                 if (free_card_index == -1 || num_video_cards >= global_flags.max_num_cards) {
1541                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
1542                         libusb_unref_device(new_dev);
1543                 } else {
1544                         // BMUSBCapture takes ownership.
1545                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
1546                         CaptureCard *card = &cards[free_card_index];
1547                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
1548                         configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr, /*is_srt_card=*/false);
1549                         card->jitter_history.clear();
1550                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1551                         capture->start_bm_capture();
1552                 }
1553         }
1554
1555 #ifdef HAVE_SRT
1556         // Same, for SRT inputs.
1557         for (SRTSOCKET sock : hotplugged_srt_cards_copy) {
1558                 char name[256];
1559                 int namelen = sizeof(name);
1560                 srt_getsockopt(sock, /*ignored=*/0, SRTO_STREAMID, name, &namelen);
1561                 string stream_id(name, namelen);
1562
1563                 // Look for a fake capture card where we can stick this in.
1564                 // Prioritize ones that previously held SRT streams with the
1565                 // same stream ID, if any exist -- and it multiple exist,
1566                 // take the one that disconnected the last.
1567                 int first_free_card_index = -1, last_matching_free_card_index = -1;
1568                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1569                         CaptureCard *card = &cards[card_index];
1570                         if (!card->is_fake_capture) {
1571                                 continue;
1572                         }
1573                         if (first_free_card_index == -1) {
1574                                 first_free_card_index = card_index;
1575                         }
1576                         if (card->last_srt_stream_id == stream_id &&
1577                             (last_matching_free_card_index == -1 ||
1578                              card->fake_capture_counter >
1579                                 cards[last_matching_free_card_index].fake_capture_counter)) {
1580                                 last_matching_free_card_index = card_index;
1581                         }
1582                 }
1583
1584                 const int free_card_index = (last_matching_free_card_index != -1)
1585                         ? last_matching_free_card_index : first_free_card_index;
1586                 if (free_card_index == -1 || num_video_cards >= global_flags.max_num_cards) {
1587                         if (stream_id.empty()) {
1588                                 stream_id = "no name";
1589                         }
1590                         fprintf(stderr, "New SRT stream connected (%s), but no free slots -- ignoring.\n", stream_id.c_str());
1591                         srt_close(sock);
1592                 } else {
1593                         // FFmpegCapture takes ownership.
1594                         if (stream_id.empty()) {
1595                                 fprintf(stderr, "New unnamed SRT stream connected, choosing slot %d.\n", free_card_index);
1596                         } else {
1597                                 fprintf(stderr, "New SRT stream connected (%s), choosing slot %d.\n", stream_id.c_str(), free_card_index);
1598                         }
1599                         CaptureCard *card = &cards[free_card_index];
1600                         FFmpegCapture *capture = new FFmpegCapture(sock, stream_id);
1601                         capture->set_card_index(free_card_index);
1602                         configure_card(free_card_index, capture, CardType::FFMPEG_INPUT, /*output=*/nullptr, /*is_srt_card=*/true);
1603                         card->srt_metrics.update_srt_stats(sock);  // Initial zero stats.
1604                         card->last_srt_stream_id = stream_id;
1605                         card->jitter_history.clear();
1606                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1607                         capture->start_bm_capture();
1608                 }
1609         }
1610 #endif
1611
1612         // Finally, newly forced-to-active fake capture cards.
1613         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1614                 CaptureCard *card = &cards[card_index];
1615                 if (card->capture == nullptr && card->force_active) {
1616                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1617                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
1618                         card->jitter_history.clear();
1619                         card->capture->start_bm_capture();
1620                 }
1621         }
1622 }
1623
1624
1625 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame, bool is_preroll, steady_clock::time_point frame_timestamp)
1626 {
1627         // Resample the audio as needed, including from previously dropped frames.
1628         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
1629                 const bool dropped_frame = (frame_num != dropped_frames);
1630                 {
1631                         // Signal to the audio thread to process this frame.
1632                         // Note that if the frame is a dropped frame, we signal that
1633                         // we don't want to use this frame as base for adjusting
1634                         // the resampler rate. The reason for this is that the timing
1635                         // of these frames is often way too late; they typically don't
1636                         // “arrive” before we synthesize them. Thus, we could end up
1637                         // in a situation where we have inserted e.g. five audio frames
1638                         // into the queue before we then start pulling five of them
1639                         // back out. This makes ResamplingQueue overestimate the delay,
1640                         // causing undue resampler changes. (We _do_ use the last,
1641                         // non-dropped frame; perhaps we should just discard that as well,
1642                         // since dropped frames are expected to be rare, and it might be
1643                         // better to just wait until we have a slightly more normal situation).
1644                         lock_guard<mutex> lock(audio_mutex);
1645                         bool adjust_rate = !dropped_frame && !is_preroll;
1646                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
1647                         audio_task_queue_changed.notify_one();
1648                 }
1649                 if (dropped_frame) {
1650                         // For dropped frames, increase the pts. Note that if the format changed
1651                         // in the meantime, we have no way of detecting that; we just have to
1652                         // assume the frame length is always the same.
1653                         pts_int += length_per_frame;
1654                 }
1655         }
1656 }
1657
1658 void Mixer::render_one_frame(int64_t duration)
1659 {
1660         // Determine the time code for this frame before we start rendering.
1661         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1662         if (display_timecode_on_stdout) {
1663                 printf("Timecode: '%s'\n", timecode_text.c_str());
1664         }
1665
1666         // Update Y'CbCr settings for all cards.
1667         {
1668                 lock_guard<mutex> lock(card_mutex);
1669                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1670                         YCbCrInterpretation *interpretation = &ycbcr_interpretation[card_index];
1671                         input_state.ycbcr_coefficients_auto[card_index] = interpretation->ycbcr_coefficients_auto;
1672                         input_state.ycbcr_coefficients[card_index] = interpretation->ycbcr_coefficients;
1673                         input_state.full_range[card_index] = interpretation->full_range;
1674                 }
1675         }
1676
1677         // Get the main chain from the theme, and set its state immediately.
1678         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1679         EffectChain *chain = theme_main_chain.chain;
1680         theme_main_chain.setup_chain();
1681         //theme_main_chain.chain->enable_phase_timing(true);
1682
1683         // If HDMI/SDI output is active and the user has requested auto mode,
1684         // its mode overrides the existing Y'CbCr setting for the chain.
1685         YCbCrLumaCoefficients ycbcr_output_coefficients;
1686         if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
1687                 ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
1688         } else {
1689                 ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
1690         }
1691
1692         // TODO: Reduce the duplication against theme.cpp.
1693         YCbCrFormat output_ycbcr_format;
1694         output_ycbcr_format.chroma_subsampling_x = 1;
1695         output_ycbcr_format.chroma_subsampling_y = 1;
1696         output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
1697         output_ycbcr_format.full_range = false;
1698         output_ycbcr_format.num_levels = 1 << global_flags.bit_depth;
1699         chain->change_ycbcr_output_format(output_ycbcr_format);
1700
1701         // Render main chain. If we're using zerocopy Quick Sync encoding
1702         // (the default case), we take an extra copy of the created outputs,
1703         // so that we can display it back to the screen later (it's less memory
1704         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1705         // Ideally, we'd like to avoid taking copies and just use the main textures
1706         // for display as well, but they're just views into VA-API memory and must be
1707         // unmapped during encoding, so we can't use them for display, unfortunately.
1708         GLuint y_tex, cbcr_full_tex, cbcr_tex;
1709         GLuint y_copy_tex, cbcr_copy_tex = 0;
1710         GLuint y_display_tex, cbcr_display_tex;
1711         GLenum y_type = (global_flags.bit_depth > 8) ? GL_R16 : GL_R8;
1712         GLenum cbcr_type = (global_flags.bit_depth > 8) ? GL_RG16 : GL_RG8;
1713         const bool is_zerocopy = video_encoder->is_zerocopy();
1714         if (is_zerocopy) {
1715                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1716                 y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1717                 cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1718
1719                 y_display_tex = y_copy_tex;
1720                 cbcr_display_tex = cbcr_copy_tex;
1721
1722                 // y_tex and cbcr_tex will be given by VideoEncoder.
1723         } else {
1724                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1725                 y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1726                 cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1727
1728                 y_display_tex = y_tex;
1729                 cbcr_display_tex = cbcr_tex;
1730         }
1731
1732         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1733         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1734         assert(got_frame);
1735
1736         GLuint fbo;
1737         if (is_zerocopy) {
1738                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1739         } else {
1740                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
1741         }
1742         check_error();
1743         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1744
1745         if (display_timecode_in_stream) {
1746                 // Render the timecode on top.
1747                 timecode_renderer->render_timecode(fbo, timecode_text);
1748         }
1749
1750         resource_pool->release_fbo(fbo);
1751
1752         if (is_zerocopy) {
1753                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1754         } else {
1755                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1756         }
1757         if (output_card_index != -1) {
1758                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
1759         }
1760         resource_pool->release_2d_texture(cbcr_full_tex);
1761
1762         // Set the right state for the Y' and CbCr textures we use for display.
1763         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1764         glBindTexture(GL_TEXTURE_2D, y_display_tex);
1765         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1766         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1767         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1768
1769         glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
1770         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1771         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1772         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1773
1774         RefCountedGLsync fence = video_encoder->end_frame();
1775
1776         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1777         // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
1778         DisplayFrame live_frame;
1779         live_frame.chain = display_chain.get();
1780         live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
1781                 display_input->set_texture_num(0, y_display_tex);
1782                 display_input->set_texture_num(1, cbcr_display_tex);
1783         };
1784         live_frame.ready_fence = fence;
1785         live_frame.input_frames = {};
1786         live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
1787         output_channel[OUTPUT_LIVE].output_frame(move(live_frame));
1788
1789         // Set up preview and any additional channels.
1790         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1791                 DisplayFrame display_frame;
1792                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1793                 display_frame.chain = move(chain.chain);
1794                 display_frame.setup_chain = move(chain.setup_chain);
1795                 display_frame.ready_fence = fence;
1796                 display_frame.input_frames = move(chain.input_frames);
1797                 display_frame.temp_textures = {};
1798                 output_channel[i].output_frame(move(display_frame));
1799         }
1800 }
1801
1802 void Mixer::audio_thread_func()
1803 {
1804         pthread_setname_np(pthread_self(), "Mixer_Audio");
1805
1806         while (!should_quit) {
1807                 AudioTask task;
1808
1809                 {
1810                         unique_lock<mutex> lock(audio_mutex);
1811                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1812                         if (should_quit) {
1813                                 return;
1814                         }
1815                         task = audio_task_queue.front();
1816                         audio_task_queue.pop();
1817                 }
1818
1819                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1820                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1821                 vector<float> samples_out = audio_mixer->get_output(
1822                         task.frame_timestamp,
1823                         task.num_samples,
1824                         rate_adjustment_policy);
1825
1826                 // Send the samples to the sound card, then add them to the output.
1827                 if (alsa) {
1828                         alsa->write(samples_out);
1829                 }
1830                 if (output_card_index != -1) {
1831                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1832                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1833                 }
1834                 video_encoder->add_audio(task.pts_int, move(samples_out));
1835         }
1836 }
1837
1838 void Mixer::release_display_frame(DisplayFrame *frame)
1839 {
1840         for (GLuint texnum : frame->temp_textures) {
1841                 resource_pool->release_2d_texture(texnum);
1842         }
1843         frame->temp_textures.clear();
1844         frame->ready_fence.reset();
1845         frame->input_frames.clear();
1846 }
1847
1848 void Mixer::start()
1849 {
1850         mixer_thread = thread(&Mixer::thread_func, this);
1851         audio_thread = thread(&Mixer::audio_thread_func, this);
1852 }
1853
1854 void Mixer::quit()
1855 {
1856         should_quit = true;
1857         audio_task_queue_changed.notify_one();
1858         mixer_thread.join();
1859         audio_thread.join();
1860 #ifdef HAVE_SRT
1861         if (global_flags.srt_port >= 0) {
1862                 // There's seemingly no other reasonable way to wake up the thread
1863                 // (libsrt's epoll equivalent is busy-waiting).
1864                 int sock = srt_create_socket();
1865                 if (sock != -1) {
1866                         sockaddr_in6 addr;
1867                         memset(&addr, 0, sizeof(addr));
1868                         addr.sin6_family = AF_INET6;
1869                         addr.sin6_addr = IN6ADDR_LOOPBACK_INIT;
1870                         addr.sin6_port = htons(global_flags.srt_port);
1871                         srt_connect(sock, (sockaddr *)&addr, sizeof(addr));
1872                         srt_close(sock);
1873                 }
1874                 srt_thread.join();
1875         }
1876 #endif
1877 }
1878
1879 void Mixer::transition_clicked(int transition_num)
1880 {
1881         theme->transition_clicked(transition_num, pts());
1882 }
1883
1884 void Mixer::channel_clicked(int preview_num)
1885 {
1886         theme->channel_clicked(preview_num);
1887 }
1888
1889 YCbCrInterpretation Mixer::get_input_ycbcr_interpretation(unsigned card_index) const
1890 {
1891         lock_guard<mutex> lock(card_mutex);
1892         return ycbcr_interpretation[card_index];
1893 }
1894
1895 void Mixer::set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation)
1896 {
1897         lock_guard<mutex> lock(card_mutex);
1898         ycbcr_interpretation[card_index] = interpretation;
1899 }
1900
1901 void Mixer::start_mode_scanning(unsigned card_index)
1902 {
1903         assert(card_index < MAX_VIDEO_CARDS);
1904         if (cards[card_index].capture == nullptr) {
1905                 // Inactive card. Should never happen.
1906                 return;
1907         }
1908         if (is_mode_scanning[card_index]) {
1909                 return;
1910         }
1911         is_mode_scanning[card_index] = true;
1912         mode_scanlist[card_index].clear();
1913         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1914                 mode_scanlist[card_index].push_back(mode.first);
1915         }
1916         assert(!mode_scanlist[card_index].empty());
1917         mode_scanlist_index[card_index] = 0;
1918         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1919         last_mode_scan_change[card_index] = steady_clock::now();
1920 }
1921
1922 map<uint32_t, VideoMode> Mixer::get_available_output_video_modes() const
1923 {
1924         assert(desired_output_card_index != -1);
1925         lock_guard<mutex> lock(card_mutex);
1926         return cards[desired_output_card_index].output->get_available_video_modes();
1927 }
1928
1929 string Mixer::get_ffmpeg_filename(unsigned card_index) const
1930 {
1931         assert(card_index < MAX_VIDEO_CARDS);
1932         assert(cards[card_index].type == CardType::FFMPEG_INPUT);
1933         return ((FFmpegCapture *)(cards[card_index].capture.get()))->get_filename();
1934 }
1935
1936 void Mixer::set_ffmpeg_filename(unsigned card_index, const string &filename) {
1937         assert(card_index < MAX_VIDEO_CARDS);
1938         assert(cards[card_index].type == CardType::FFMPEG_INPUT);
1939         ((FFmpegCapture *)(cards[card_index].capture.get()))->change_filename(filename);
1940 }
1941
1942 void Mixer::wait_for_next_frame()
1943 {
1944         unique_lock<mutex> lock(frame_num_mutex);
1945         unsigned old_frame_num = frame_num;
1946         frame_num_updated.wait_for(lock, seconds(1),  // Timeout is just in case.
1947                 [old_frame_num, this]{ return this->frame_num > old_frame_num; });
1948 }
1949
1950 Mixer::OutputChannel::~OutputChannel()
1951 {
1952         if (has_current_frame) {
1953                 parent->release_display_frame(&current_frame);
1954         }
1955         if (has_ready_frame) {
1956                 parent->release_display_frame(&ready_frame);
1957         }
1958 }
1959
1960 void Mixer::OutputChannel::output_frame(DisplayFrame &&frame)
1961 {
1962         // Store this frame for display. Remove the ready frame if any
1963         // (it was seemingly never used).
1964         {
1965                 lock_guard<mutex> lock(frame_mutex);
1966                 if (has_ready_frame) {
1967                         parent->release_display_frame(&ready_frame);
1968                 }
1969                 ready_frame = move(frame);
1970                 has_ready_frame = true;
1971
1972                 // Call the callbacks under the mutex (they should be short),
1973                 // so that we don't race against a callback removal.
1974                 for (const auto &key_and_callback : new_frame_ready_callbacks) {
1975                         key_and_callback.second();
1976                 }
1977         }
1978
1979         // Reduce the number of callbacks by filtering duplicates. The reason
1980         // why we bother doing this is that Qt seemingly can get into a state
1981         // where its builds up an essentially unbounded queue of signals,
1982         // consuming more and more memory, and there's no good way of collapsing
1983         // user-defined signals or limiting the length of the queue.
1984         if (transition_names_updated_callback) {
1985                 vector<string> transition_names = global_mixer->get_transition_names();
1986                 bool changed = false;
1987                 if (transition_names.size() != last_transition_names.size()) {
1988                         changed = true;
1989                 } else {
1990                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1991                                 if (transition_names[i] != last_transition_names[i]) {
1992                                         changed = true;
1993                                         break;
1994                                 }
1995                         }
1996                 }
1997                 if (changed) {
1998                         transition_names_updated_callback(transition_names);
1999                         last_transition_names = transition_names;
2000                 }
2001         }
2002         if (name_updated_callback) {
2003                 string name = global_mixer->get_channel_name(channel);
2004                 if (name != last_name) {
2005                         name_updated_callback(name);
2006                         last_name = name;
2007                 }
2008         }
2009         if (color_updated_callback) {
2010                 string color = global_mixer->get_channel_color(channel);
2011                 if (color != last_color) {
2012                         color_updated_callback(color);
2013                         last_color = color;
2014                 }
2015         }
2016 }
2017
2018 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
2019 {
2020         lock_guard<mutex> lock(frame_mutex);
2021         if (!has_current_frame && !has_ready_frame) {
2022                 return false;
2023         }
2024
2025         if (has_current_frame && has_ready_frame) {
2026                 // We have a new ready frame. Toss the current one.
2027                 parent->release_display_frame(&current_frame);
2028                 has_current_frame = false;
2029         }
2030         if (has_ready_frame) {
2031                 assert(!has_current_frame);
2032                 current_frame = move(ready_frame);
2033                 ready_frame.ready_fence.reset();  // Drop the refcount.
2034                 ready_frame.input_frames.clear();  // Drop the refcounts.
2035                 has_current_frame = true;
2036                 has_ready_frame = false;
2037         }
2038
2039         *frame = current_frame;
2040         return true;
2041 }
2042
2043 void Mixer::OutputChannel::add_frame_ready_callback(void *key, Mixer::new_frame_ready_callback_t callback)
2044 {
2045         lock_guard<mutex> lock(frame_mutex);
2046         new_frame_ready_callbacks[key] = callback;
2047 }
2048
2049 void Mixer::OutputChannel::remove_frame_ready_callback(void *key)
2050 {
2051         lock_guard<mutex> lock(frame_mutex);
2052         new_frame_ready_callbacks.erase(key);
2053 }
2054
2055 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
2056 {
2057         transition_names_updated_callback = callback;
2058 }
2059
2060 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
2061 {
2062         name_updated_callback = callback;
2063 }
2064
2065 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
2066 {
2067         color_updated_callback = callback;
2068 }
2069
2070 #ifdef HAVE_SRT
2071 void Mixer::start_srt()
2072 {
2073         SRTSOCKET sock = srt_create_socket();
2074         sockaddr_in6 addr;
2075         memset(&addr, 0, sizeof(addr));
2076         addr.sin6_family = AF_INET6;
2077         addr.sin6_port = htons(global_flags.srt_port);
2078
2079         int zero = 0;
2080         int err = srt_setsockopt(sock, /*level=*/0, SRTO_IPV6ONLY, &zero, sizeof(zero));
2081         if (err != 0) {
2082                 fprintf(stderr, "srt_setsockopt(SRTO_IPV6ONLY): %s\n", srt_getlasterror_str());
2083                 abort();
2084         }
2085         err = srt_bind(sock, (sockaddr *)&addr, sizeof(addr));
2086         if (err != 0) {
2087                 fprintf(stderr, "srt_bind: %s\n", srt_getlasterror_str());
2088                 abort();
2089         }
2090         err = srt_listen(sock, MAX_VIDEO_CARDS);
2091         if (err != 0) {
2092                 fprintf(stderr, "srt_listen: %s\n", srt_getlasterror_str());
2093                 abort();
2094         }
2095
2096         srt_thread = thread([this, sock] {
2097                 sockaddr_in6 addr;
2098                 for ( ;; ) {
2099                         int sa_len = sizeof(addr);
2100                         int clientsock = srt_accept(sock, (sockaddr *)&addr, &sa_len);
2101                         if (should_quit) {
2102                                 if (clientsock != -1) {
2103                                         srt_close(clientsock);
2104                                 }
2105                                 break;
2106                         }
2107                         if (!global_flags.enable_srt) {  // Runtime UI toggle.
2108                                 // Perhaps not as good as never listening in the first place,
2109                                 // but much simpler to turn on and off.
2110                                 srt_close(clientsock);
2111                                 continue;
2112                         }
2113                         lock_guard<mutex> lock(hotplug_mutex);
2114                         hotplugged_srt_cards.push_back(clientsock);
2115                 }
2116                 srt_close(sock);
2117         });
2118 }
2119 #endif
2120
2121 string Mixer::description_for_card(unsigned card_index)
2122 {
2123         CaptureCard *card = &cards[card_index];
2124         if (card->capture == nullptr) {
2125                 // Should never be called for inactive cards, but OK.
2126                 char buf[256];
2127                 snprintf(buf, sizeof(buf), "Inactive capture card %u", card_index);
2128                 return buf;
2129         }
2130         if (card->type != CardType::FFMPEG_INPUT) {
2131                 char buf[256];
2132                 snprintf(buf, sizeof(buf), "Capture card %u (%s)", card_index, card->capture->get_description().c_str());
2133                 return buf;
2134         }
2135
2136         // Number (non-SRT) FFmpeg inputs from zero, separately from the capture cards,
2137         // since it's not too obvious for the user that they are “cards”.
2138         unsigned ffmpeg_index = 0;
2139         for (unsigned i = 0; i < card_index; ++i) {
2140                 CaptureCard *other_card = &cards[i];
2141                 if (other_card->type == CardType::FFMPEG_INPUT && !is_srt_card(other_card)) {
2142                         ++ffmpeg_index;
2143                 }
2144         }
2145         char buf[256];
2146         snprintf(buf, sizeof(buf), "Video input %u (%s)", ffmpeg_index, card->capture->get_description().c_str());
2147         return buf;
2148 }
2149
2150 bool Mixer::is_srt_card(const Mixer::CaptureCard *card)
2151 {
2152 #ifdef HAVE_SRT
2153         if (card->type == CardType::FFMPEG_INPUT) {
2154                 int srt_sock = static_cast<FFmpegCapture *>(card->capture.get())->get_srt_sock();
2155                 return srt_sock != -1;
2156         }
2157 #endif
2158         return false;
2159 }
2160
2161 mutex RefCountedGLsync::fence_lock;