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                 assert(card_type == CardType::FAKE_CAPTURE);
 585         }
 586
 587         CaptureCard *card = &cards[card_index];
 588         if (card->capture != nullptr) {
 589                 card_mutex.unlock();  // The dequeue thread could be waiting for bm_frame().
 590                 card->capture->stop_dequeue_thread();
 591                 card_mutex.lock();
 592         }
 593         card->capture.reset(capture);
 594         card->is_fake_capture = (card_type == CardType::FAKE_CAPTURE);
 595         if (card->is_fake_capture) {
 596                 card->fake_capture_counter = fake_capture_counter++;
 597         }
 598         card->is_cef_capture = (card_type == CardType::CEF_INPUT);
 599         card->may_have_dropped_last_frame = false;
 600         card->type = card_type;
 601         if (card->output.get() != output) {
 602                 card->output.reset(output);
 603         }
 604
 605         PixelFormat pixel_format;
 606         if (card_type == CardType::FFMPEG_INPUT) {
 607                 pixel_format = capture->get_current_pixel_format();
 608         } else if (card_type == CardType::CEF_INPUT) {
 609                 pixel_format = PixelFormat_8BitBGRA;
 610         } else if (global_flags.bit_depth > 8) {
 611                 pixel_format = PixelFormat_10BitYCbCr;
 612         } else {
 613                 pixel_format = PixelFormat_8BitYCbCr;
 614         }
 615
 616         if (is_active) {
 617                 card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 618                 if (card->frame_allocator == nullptr) {
 619                         card->frame_allocator.reset(new PBOFrameAllocator(pixel_format, FRAME_SIZE, global_flags.width, global_flags.height, card_index, mjpeg_encoder.get()));
 620                 } else {
 621                         // The format could have changed, but we cannot reset the allocator
 622                         // and create a new one from scratch, since there may be allocated
 623                         // frames from it that expect to call release_frame() on it.
 624                         // Instead, ask the allocator to create new frames for us and discard
 625                         // any old ones as they come back. This takes the mutex while
 626                         // allocating, but nothing should really be sending frames in there
 627                         // right now anyway (start_bm_capture() has not been called yet).
 628                         card->frame_allocator->reconfigure(pixel_format, FRAME_SIZE, global_flags.width, global_flags.height, card_index, mjpeg_encoder.get());
 629                 }
 630                 card->capture->set_video_frame_allocator(card->frame_allocator.get());
 631                 if (card->surface == nullptr) {
 632                         card->surface = create_surface_with_same_format(mixer_surface);
 633                 }
 634                 while (!card->new_frames.empty()) card->new_frames.pop_front();
 635                 card->last_timecode = -1;
 636                 card->capture->set_pixel_format(pixel_format);
 637                 card->capture->configure_card();
 638
 639                 // NOTE: start_bm_capture() happens in thread_func().
 640         }
 641
 642         if (is_srt_card) {
 643                 assert(card_type == CardType::FFMPEG_INPUT);
 644         }
 645
 646         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 647         unsigned num_channels = card_type == CardType::LIVE_CARD ? 8 : 2;
 648         if (is_active) {
 649                 audio_mixer->set_device_parameters(device, card->capture->get_description(), card_type, num_channels, /*active=*/true);
 650         } else {
 651                 // Note: Keeps the previous name, if any.
 652                 char name[32];
 653                 snprintf(name, sizeof(name), "Fake card %u", card_index + 1);
 654                 audio_mixer->set_device_parameters(device, name, card_type, num_channels, /*active=*/false);
 655         }
 656         audio_mixer->reset_resampler(device);
 657         audio_mixer->trigger_state_changed_callback();
 658
 659         // Unregister old metrics, if any.
 660         if (!card->labels.empty()) {
 661                 const vector<pair<string, string>> &labels = card->labels;
 662                 card->jitter_history.unregister_metrics(labels);
 663                 card->queue_length_policy.unregister_metrics(labels);
 664                 global_metrics.remove_if_exists("input_received_frames", labels);
 665                 global_metrics.remove_if_exists("input_dropped_frames_jitter", labels);
 666                 global_metrics.remove_if_exists("input_dropped_frames_error", labels);
 667                 global_metrics.remove_if_exists("input_dropped_frames_resets", labels);
 668                 global_metrics.remove_if_exists("input_queue_length_frames", labels);
 669                 global_metrics.remove_if_exists("input_queue_duped_frames", labels);
 670
 671                 global_metrics.remove_if_exists("input_has_signal_bool", labels);
 672                 global_metrics.remove_if_exists("input_is_connected_bool", labels);
 673                 global_metrics.remove_if_exists("input_interlaced_bool", labels);
 674                 global_metrics.remove_if_exists("input_width_pixels", labels);
 675                 global_metrics.remove_if_exists("input_height_pixels", labels);
 676                 global_metrics.remove_if_exists("input_frame_rate_nom", labels);
 677                 global_metrics.remove_if_exists("input_frame_rate_den", labels);
 678                 global_metrics.remove_if_exists("input_sample_rate_hz", labels);
 679
 680                 card->srt_metrics.deinit(labels);
 681         }
 682
 683         if (is_active) {
 684                 // Register metrics.
 685                 vector<pair<string, string>> labels;
 686                 char card_name[64];
 687                 snprintf(card_name, sizeof(card_name), "%d", card_index);
 688                 labels.emplace_back("card", card_name);
 689
 690                 switch (card_type) {
 691                 case CardType::LIVE_CARD:
 692                         labels.emplace_back("cardtype", "live");
 693                         break;
 694                 case CardType::FAKE_CAPTURE:
 695                         labels.emplace_back("cardtype", "fake");
 696                         break;
 697                 case CardType::FFMPEG_INPUT:
 698                         if (is_srt_card) {
 699                                 labels.emplace_back("cardtype", "srt");
 700                         } else {
 701                                 labels.emplace_back("cardtype", "ffmpeg");
 702                         }
 703                         break;
 704                 case CardType::CEF_INPUT:
 705                         labels.emplace_back("cardtype", "cef");
 706                         break;
 707                 default:
 708                         assert(false);
 709                 }
 710                 card->jitter_history.register_metrics(labels);
 711                 card->queue_length_policy.register_metrics(labels);
 712                 global_metrics.add("input_received_frames", labels, &card->metric_input_received_frames);
 713                 global_metrics.add("input_dropped_frames_jitter", labels, &card->metric_input_dropped_frames_jitter);
 714                 global_metrics.add("input_dropped_frames_error", labels, &card->metric_input_dropped_frames_error);
 715                 global_metrics.add("input_dropped_frames_resets", labels, &card->metric_input_resets);
 716                 global_metrics.add("input_queue_length_frames", labels, &card->metric_input_queue_length_frames, Metrics::TYPE_GAUGE);
 717                 global_metrics.add("input_queue_duped_frames", labels, &card->metric_input_duped_frames);
 718
 719                 global_metrics.add("input_has_signal_bool", labels, &card->metric_input_has_signal_bool, Metrics::TYPE_GAUGE);
 720                 global_metrics.add("input_is_connected_bool", labels, &card->metric_input_is_connected_bool, Metrics::TYPE_GAUGE);
 721                 global_metrics.add("input_interlaced_bool", labels, &card->metric_input_interlaced_bool, Metrics::TYPE_GAUGE);
 722                 global_metrics.add("input_width_pixels", labels, &card->metric_input_width_pixels, Metrics::TYPE_GAUGE);
 723                 global_metrics.add("input_height_pixels", labels, &card->metric_input_height_pixels, Metrics::TYPE_GAUGE);
 724                 global_metrics.add("input_frame_rate_nom", labels, &card->metric_input_frame_rate_nom, Metrics::TYPE_GAUGE);
 725                 global_metrics.add("input_frame_rate_den", labels, &card->metric_input_frame_rate_den, Metrics::TYPE_GAUGE);
 726                 global_metrics.add("input_sample_rate_hz", labels, &card->metric_input_sample_rate_hz, Metrics::TYPE_GAUGE);
 727
 728                 if (is_srt_card) {
 729                         card->srt_metrics.init(labels);
 730                 }
 731
 732                 card->labels = labels;
 733         } else {
 734                 card->labels.clear();
 735         }
 736 }
 737
 738 void Mixer::set_output_card_internal(int card_index)
 739 {
 740         // We don't really need to take card_mutex, since we're in the mixer
 741         // thread and don't mess with any queues (which is the only thing that happens
 742         // from other threads), but it's probably the safest in the long run.
 743         unique_lock<mutex> lock(card_mutex);
 744         if (output_card_index != -1) {
 745                 // Switch the old card from output to input.
 746                 CaptureCard *old_card = &cards[output_card_index];
 747                 old_card->output->end_output();
 748
 749                 // Stop the fake card that we put into place.
 750                 // This needs to _not_ happen under the mutex, to avoid deadlock
 751                 // (delivering the last frame needs to take the mutex).
 752                 CaptureInterface *fake_capture = old_card->capture.get();
 753                 lock.unlock();
 754                 fake_capture->stop_dequeue_thread();
 755                 lock.lock();
 756                 old_card->capture = move(old_card->parked_capture);  // TODO: reset the metrics
 757                 old_card->is_fake_capture = false;
 758                 old_card->capture->start_bm_capture();
 759         }
 760         if (card_index != -1) {
 761                 CaptureCard *card = &cards[card_index];
 762                 CaptureInterface *capture = card->capture.get();
 763                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
 764                 // several seconds to complete (blocking on DisableVideoInput);
 765                 // see if we can maybe do it asynchronously.
 766                 lock.unlock();
 767                 capture->stop_dequeue_thread();
 768                 lock.lock();
 769                 card->parked_capture = move(card->capture);
 770                 CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 771                 configure_card(card_index, fake_capture, CardType::FAKE_CAPTURE, card->output.release(), /*is_srt_card=*/false);
 772                 card->jitter_history.clear();
 773                 card->capture->start_bm_capture();
 774                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
 775                 card->output->start_output(desired_output_video_mode, pts_int, /*is_master_card=*/output_card_is_master);
 776         }
 777         output_card_index = card_index;
 778         output_jitter_history.clear();
 779 }
 780
 781 namespace {
 782
 783 int unwrap_timecode(uint16_t current_wrapped, int last)
 784 {
 785         uint16_t last_wrapped = last & 0xffff;
 786         if (current_wrapped > last_wrapped) {
 787                 return (last & ~0xffff) | current_wrapped;
 788         } else {
 789                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 790         }
 791 }
 792
 793 }  // namespace
 794
 795 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 796                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 797                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 798 {
 799         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 800         CaptureCard *card = &cards[card_index];
 801
 802         ++card->metric_input_received_frames;
 803         card->metric_input_has_signal_bool = video_format.has_signal;
 804         card->metric_input_is_connected_bool = video_format.is_connected;
 805         card->metric_input_interlaced_bool = video_format.interlaced;
 806         card->metric_input_width_pixels = video_format.width;
 807         card->metric_input_height_pixels = video_format.height;
 808         card->metric_input_frame_rate_nom = video_format.frame_rate_nom;
 809         card->metric_input_frame_rate_den = video_format.frame_rate_den;
 810         card->metric_input_sample_rate_hz = audio_format.sample_rate;
 811
 812         if (is_mode_scanning[card_index]) {
 813                 if (video_format.has_signal) {
 814                         // Found a stable signal, so stop scanning.
 815                         is_mode_scanning[card_index] = false;
 816                 } else {
 817                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
 818                         steady_clock::time_point now = steady_clock::now();
 819                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 820                         if (sec_since_last_switch > switch_time_s) {
 821                                 // It isn't this mode; try the next one.
 822                                 mode_scanlist_index[card_index]++;
 823                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 824                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 825                                 last_mode_scan_change[card_index] = now;
 826                         }
 827                 }
 828         }
 829
 830         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 831         assert(frame_length > 0);
 832
 833         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;
 834         if (num_samples > OUTPUT_FREQUENCY / 10 && card->type != CardType::FFMPEG_INPUT) {
 835                 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",
 836                         description_for_card(card_index).c_str(), int(audio_frame.len), int(audio_offset),
 837                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 838                 if (video_frame.owner) {
 839                         video_frame.owner->release_frame(video_frame);
 840                 }
 841                 if (audio_frame.owner) {
 842                         audio_frame.owner->release_frame(audio_frame);
 843                 }
 844                 return;
 845         }
 846
 847         int dropped_frames = 0;
 848         if (card->last_timecode != -1) {
 849                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 850         }
 851
 852         // Number of samples per frame if we need to insert silence.
 853         // (Could be nonintegral, but resampling will save us then.)
 854         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 855
 856         if (dropped_frames > TYPICAL_FPS * 2) {
 857                 fprintf(stderr, "%s lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 858                         description_for_card(card_index).c_str(), card->last_timecode, timecode);
 859                 audio_mixer->reset_resampler(device);
 860                 dropped_frames = 0;
 861                 ++card->metric_input_resets;
 862         } else if (dropped_frames > 0) {
 863                 // Insert silence as needed.
 864                 fprintf(stderr, "%s dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 865                         description_for_card(card_index).c_str(), dropped_frames, timecode);
 866                 card->metric_input_dropped_frames_error += dropped_frames;
 867
 868                 bool success;
 869                 do {
 870                         success = audio_mixer->add_silence(device, silence_samples, dropped_frames);
 871                 } while (!success);
 872         }
 873
 874         if (num_samples > 0) {
 875                 audio_mixer->add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, audio_frame.received_timestamp);
 876
 877                 // Audio for the MJPEG stream. We don't resample; audio that's not in 48 kHz
 878                 // just gets dropped for now.
 879                 //
 880                 // Only bother doing MJPEG encoding if there are any connected clients
 881                 // that want the stream.
 882                 if (httpd.get_num_connected_multicam_clients() > 0 ||
 883                     httpd.get_num_connected_siphon_clients(card_index) > 0) {
 884                         vector<int32_t> converted_samples = convert_audio_to_fixed32(audio_frame.data + audio_offset, num_samples, audio_format, 2);
 885                         lock_guard<mutex> lock(card_mutex);
 886                         if (card->new_raw_audio.empty()) {
 887                                 card->new_raw_audio = move(converted_samples);
 888                         } else {
 889                                 // For raw audio, we don't really synchronize audio and video;
 890                                 // we just put the audio in frame by frame, and if a video frame is
 891                                 // dropped, we still keep the audio, which means it will be added
 892                                 // to the beginning of the next frame. It would probably be better
 893                                 // to move the audio pts earlier to show this, but most players can
 894                                 // live with some jitter, and in a lot of ways, it's much nicer for
 895                                 // Futatabi to have all audio locked to a video frame.
 896                                 card->new_raw_audio.insert(card->new_raw_audio.end(), converted_samples.begin(), converted_samples.end());
 897
 898                                 // Truncate to one second, just to be sure we don't have infinite buildup in case of weirdness.
 899                                 if (card->new_raw_audio.size() > OUTPUT_FREQUENCY * 2) {
 900                                         size_t excess_samples = card->new_raw_audio.size() - OUTPUT_FREQUENCY * 2;
 901                                         card->new_raw_audio.erase(card->new_raw_audio.begin(), card->new_raw_audio.begin() + excess_samples);
 902                                 }
 903                         }
 904                 }
 905         }
 906
 907         // Done with the audio, so release it.
 908         if (audio_frame.owner) {
 909                 audio_frame.owner->release_frame(audio_frame);
 910         }
 911
 912         card->last_timecode = timecode;
 913
 914         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 915         if (card->type == CardType::FFMPEG_INPUT && userdata != nullptr) {
 916                 FFmpegCapture *ffmpeg_capture = static_cast<FFmpegCapture *>(card->capture.get());
 917                 userdata->has_last_subtitle = ffmpeg_capture->get_has_last_subtitle();
 918                 userdata->last_subtitle = ffmpeg_capture->get_last_subtitle();
 919         }
 920 #ifdef HAVE_SRT
 921         if (card->type == CardType::FFMPEG_INPUT) {
 922                 int srt_sock = static_cast<FFmpegCapture *>(card->capture.get())->get_srt_sock();
 923                 if (srt_sock != -1) {
 924                         card->srt_metrics.update_srt_stats(srt_sock);
 925                 }
 926         }
 927 #endif
 928
 929         size_t y_offset, cbcr_offset;
 930         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
 931         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
 932                 // The calculation above is wrong for planar Y'CbCr, so just override it.
 933                 assert(card->type == CardType::FFMPEG_INPUT);
 934                 assert(video_offset == 0);
 935                 expected_length = video_frame.len;
 936
 937                 userdata->ycbcr_format = (static_cast<FFmpegCapture *>(card->capture.get()))->get_current_frame_ycbcr_format();
 938                 y_offset = 0;
 939                 cbcr_offset = video_format.width * video_format.height;
 940         } else {
 941                 // All the other Y'CbCr formats are 4:2:2.
 942                 y_offset = video_frame.size / 2 + video_offset / 2;
 943                 cbcr_offset = video_offset / 2;
 944         }
 945         if (video_frame.len - video_offset == 0 ||
 946             video_frame.len - video_offset != expected_length) {
 947                 if (video_frame.len != 0) {
 948                         printf("%s: Dropping video frame with wrong length (%zu; expected %zu)\n",
 949                                 description_for_card(card_index).c_str(), video_frame.len - video_offset, expected_length);
 950                 }
 951                 if (video_frame.owner) {
 952                         video_frame.owner->release_frame(video_frame);
 953                 }
 954
 955                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 956                 // so that pts can go up accordingly.
 957                 {
 958                         lock_guard<mutex> lock(card_mutex);
 959                         CaptureCard::NewFrame new_frame;
 960                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 961                         new_frame.length = frame_length;
 962                         new_frame.interlaced = false;
 963                         new_frame.dropped_frames = dropped_frames;
 964                         new_frame.received_timestamp = video_frame.received_timestamp;
 965                         card->new_frames.push_back(move(new_frame));
 966                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
 967                 }
 968                 card->new_frames_changed.notify_all();
 969                 return;
 970         }
 971
 972         unsigned num_fields = video_format.interlaced ? 2 : 1;
 973         steady_clock::time_point frame_upload_start;
 974         if (video_format.interlaced) {
 975                 // Send the two fields along as separate frames; the other side will need to add
 976                 // a deinterlacer to actually get this right.
 977                 assert(video_format.height % 2 == 0);
 978                 video_format.height /= 2;
 979                 assert(frame_length % 2 == 0);
 980                 frame_length /= 2;
 981                 num_fields = 2;
 982                 frame_upload_start = steady_clock::now();
 983         }
 984         assert(userdata != nullptr);
 985         userdata->last_interlaced = video_format.interlaced;
 986         userdata->last_has_signal = video_format.has_signal;
 987         userdata->last_is_connected = video_format.is_connected;
 988         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 989         userdata->last_frame_rate_den = video_format.frame_rate_den;
 990         RefCountedFrame frame(video_frame);
 991
 992         // Send the frames on to the main thread, which will upload and process htem.
 993         // It is entirely possible to upload them in the same thread (and it might even be
 994         // faster, depending on the GPU and driver), but it appears to be trickling
 995         // driver bugs very easily.
 996         //
 997         // Note that this means we must hold on to the actual frame data in <userdata>
 998         // until the upload is done, but we hold on to <frame> much longer than that
 999         // (in fact, all the way until we no longer use the texture in rendering).
1000         for (unsigned field = 0; field < num_fields; ++field) {
1001                 if (field == 1) {
1002                         // Don't upload the second field as fast as we can; wait until
1003                         // the field time has approximately passed. (Otherwise, we could
1004                         // get timing jitter against the other sources, and possibly also
1005                         // against the video display, although the latter is not as critical.)
1006                         // This requires our system clock to be reasonably close to the
1007                         // video clock, but that's not an unreasonable assumption.
1008                         steady_clock::time_point second_field_start = frame_upload_start +
1009                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
1010                         this_thread::sleep_until(second_field_start);
1011                 }
1012
1013                 {
1014                         lock_guard<mutex> lock(card_mutex);
1015                         CaptureCard::NewFrame new_frame;
1016                         new_frame.frame = frame;
1017                         new_frame.length = frame_length;
1018                         new_frame.field = field;
1019                         new_frame.interlaced = video_format.interlaced;
1020                         new_frame.dropped_frames = dropped_frames;
1021                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
1022                         new_frame.video_format = video_format;
1023                         new_frame.video_offset = video_offset;
1024                         new_frame.y_offset = y_offset;
1025                         new_frame.cbcr_offset = cbcr_offset;
1026                         new_frame.texture_uploaded = false;
1027                         if (card->type == CardType::FFMPEG_INPUT) {
1028                                 FFmpegCapture *ffmpeg_capture = static_cast<FFmpegCapture *>(card->capture.get());
1029                                 new_frame.neutral_color = ffmpeg_capture->get_last_neutral_color();
1030                         }
1031                         card->new_frames.push_back(move(new_frame));
1032                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
1033                         card->may_have_dropped_last_frame = false;
1034                 }
1035                 card->new_frames_changed.notify_all();
1036         }
1037 }
1038
1039 void Mixer::upload_texture_for_frame(
1040         int field, bmusb::VideoFormat video_format,
1041         size_t y_offset, size_t cbcr_offset, size_t video_offset, PBOFrameAllocator::Userdata *userdata)
1042 {
1043         size_t cbcr_width, cbcr_height;
1044         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
1045                 cbcr_width = video_format.width / userdata->ycbcr_format.chroma_subsampling_x;
1046                 cbcr_height = video_format.height / userdata->ycbcr_format.chroma_subsampling_y;
1047         } else {
1048                 // All the other Y'CbCr formats are 4:2:2.
1049                 cbcr_width = video_format.width / 2;
1050                 cbcr_height = video_format.height;
1051         }
1052
1053         bool interlaced_stride = video_format.interlaced && (video_format.second_field_start == 1);
1054         if (video_format.interlaced) {
1055                 cbcr_height /= 2;
1056         }
1057
1058         unsigned field_start_line;
1059         if (field == 1) {
1060                 field_start_line = video_format.second_field_start;
1061         } else {
1062                 field_start_line = video_format.extra_lines_top;
1063         }
1064
1065         // For anything not FRAME_FORMAT_YCBCR_10BIT, v210_width will be nonsensical but not used.
1066         size_t v210_width = video_format.stride / sizeof(uint32_t);
1067         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, cbcr_width, cbcr_height, v210_width);
1068
1069         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
1070         check_error();
1071
1072         switch (userdata->pixel_format) {
1073                 case PixelFormat_10BitYCbCr: {
1074                         size_t field_start = video_offset + video_format.stride * field_start_line;
1075                         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);
1076                         v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
1077                         break;
1078                 }
1079                 case PixelFormat_8BitYCbCr: {
1080                         size_t field_y_start = y_offset + video_format.width * field_start_line;
1081                         size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
1082
1083                         // Make up our own strides, since we are interleaving.
1084                         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);
1085                         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);
1086                         break;
1087                 }
1088                 case PixelFormat_8BitYCbCrPlanar: {
1089                         assert(field_start_line == 0);  // We don't really support interlaced here.
1090                         size_t field_y_start = y_offset;
1091                         size_t field_cb_start = cbcr_offset;
1092                         size_t field_cr_start = cbcr_offset + cbcr_width * cbcr_height;
1093
1094                         // Make up our own strides, since we are interleaving.
1095                         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);
1096                         upload_texture(userdata->tex_cb[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cb_start);
1097                         upload_texture(userdata->tex_cr[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cr_start);
1098                         break;
1099                 }
1100                 case PixelFormat_8BitBGRA: {
1101                         size_t field_start = video_offset + video_format.stride * field_start_line;
1102                         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);
1103                         // These could be asked to deliver mipmaps at any time.
1104                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
1105                         check_error();
1106                         glGenerateMipmap(GL_TEXTURE_2D);
1107                         check_error();
1108                         glBindTexture(GL_TEXTURE_2D, 0);
1109                         check_error();
1110                         break;
1111                 }
1112                 default:
1113                         assert(false);
1114         }
1115
1116         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
1117         check_error();
1118 }
1119
1120 void Mixer::bm_hotplug_add(libusb_device *dev)
1121 {
1122         lock_guard<mutex> lock(hotplug_mutex);
1123         hotplugged_cards.push_back(dev);
1124 }
1125
1126 void Mixer::bm_hotplug_remove(unsigned card_index)
1127 {
1128         cards[card_index].new_frames_changed.notify_all();
1129 }
1130
1131 void Mixer::thread_func()
1132 {
1133         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
1134
1135         eglBindAPI(EGL_OPENGL_API);
1136         QOpenGLContext *context = create_context(mixer_surface);
1137         if (!make_current(context, mixer_surface)) {
1138                 printf("oops\n");
1139                 abort();
1140         }
1141
1142         // Start the actual capture. (We don't want to do it before we're actually ready
1143         // to process output frames.)
1144         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1145                 if (int(card_index) != output_card_index && cards[card_index].capture != nullptr) {
1146                         cards[card_index].capture->start_bm_capture();
1147                 }
1148         }
1149
1150         BasicStats basic_stats(/*verbose=*/true, /*use_opengl=*/true);
1151         int stats_dropped_frames = 0;
1152
1153         while (!should_quit) {
1154                 if (desired_output_card_index != output_card_index) {
1155                         set_output_card_internal(desired_output_card_index);
1156                 }
1157                 if (output_card_index != -1 &&
1158                     desired_output_video_mode != output_video_mode) {
1159                         DeckLinkOutput *output = cards[output_card_index].output.get();
1160                         output->end_output();
1161                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
1162                         output->start_output(desired_output_video_mode, pts_int, /*is_master_card=*/output_card_is_master);
1163                 }
1164
1165                 {
1166                         lock_guard<mutex> lock(card_mutex);
1167                         handle_hotplugged_cards();
1168                 }
1169
1170                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
1171                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
1172
1173                 bool master_card_is_output;
1174                 unsigned master_card_index;
1175                 if (output_card_index != -1 && output_card_is_master) {
1176                         master_card_is_output = true;
1177                         master_card_index = output_card_index;
1178                 } else {
1179                         master_card_is_output = false;
1180                         master_card_index = theme->map_signal_to_card(master_clock_channel);
1181                         assert(master_card_index < MAX_VIDEO_CARDS);
1182                 }
1183
1184                 vector<int32_t> raw_audio[MAX_VIDEO_CARDS];  // For MJPEG encoding.
1185                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame, raw_audio);
1186                 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);
1187                 stats_dropped_frames += output_frame_info.dropped_frames;
1188
1189                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1190                         if (card_index == master_card_index || !has_new_frame[card_index]) {
1191                                 continue;
1192                         }
1193                         if (new_frames[card_index].frame->len == 0) {
1194                                 ++new_frames[card_index].dropped_frames;
1195                         }
1196                         if (new_frames[card_index].dropped_frames > 0) {
1197                                 printf("%s dropped %d frames before this\n",
1198                                         description_for_card(card_index).c_str(), int(new_frames[card_index].dropped_frames));
1199                         }
1200                 }
1201
1202                 // If the first card is reporting a corrupted or otherwise dropped frame,
1203                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
1204                 if (!master_card_is_output &&
1205                     new_frames[master_card_index].frame != nullptr &&  // Timeout.
1206                     new_frames[master_card_index].frame->len == 0) {
1207                         ++stats_dropped_frames;
1208                         pts_int += new_frames[master_card_index].length;
1209                         continue;
1210                 }
1211
1212                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1213                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
1214                                 continue;
1215
1216                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
1217                         assert(new_frame->frame != nullptr);
1218                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
1219                         check_error();
1220
1221                         // The new texture might need uploading before use.
1222                         if (!new_frame->texture_uploaded) {
1223                                 upload_texture_for_frame(new_frame->field, new_frame->video_format, new_frame->y_offset, new_frame->cbcr_offset,
1224                                         new_frame->video_offset, (PBOFrameAllocator::Userdata *)new_frame->frame->userdata);
1225                                 new_frame->texture_uploaded = true;
1226                         }
1227
1228                         // Only set the white balance if it actually changed. This means that the user
1229                         // is free to override the white balance in a video with no white balance information
1230                         // actually set (ie. r=g=b=1 all the time), or one where the white point is wrong,
1231                         // but frame-to-frame decisions will be heeded. We do this pretty much as late
1232                         // as possible (ie., after picking out the frame from the buffer), so that we are sure
1233                         // that the change takes effect on exactly the right frame.
1234                         if (fabs(new_frame->neutral_color.r - last_received_neutral_color[card_index].r) > 1e-3 ||
1235                             fabs(new_frame->neutral_color.g - last_received_neutral_color[card_index].g) > 1e-3 ||
1236                             fabs(new_frame->neutral_color.b - last_received_neutral_color[card_index].b) > 1e-3) {
1237                                 theme->set_wb_for_card(card_index, new_frame->neutral_color.r, new_frame->neutral_color.g, new_frame->neutral_color.b);
1238                                 last_received_neutral_color[card_index] = new_frame->neutral_color;
1239                         }
1240
1241                         if (new_frame->frame->data_copy != nullptr && mjpeg_encoder->should_encode_mjpeg_for_card(card_index)) {
1242                                 RGBTriplet neutral_color = theme->get_white_balance_for_card(card_index);
1243                                 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);
1244                         }
1245
1246                 }
1247
1248                 int64_t frame_duration = output_frame_info.frame_duration;
1249                 render_one_frame(frame_duration);
1250                 {
1251                         lock_guard<mutex> lock(frame_num_mutex);
1252                         ++frame_num;
1253                 }
1254                 frame_num_updated.notify_all();
1255                 pts_int += frame_duration;
1256
1257                 basic_stats.update(frame_num, stats_dropped_frames);
1258                 // if (frame_num % 100 == 0) chain->print_phase_timing();
1259
1260                 if (should_cut.exchange(false)) {  // Test and clear.
1261                         video_encoder->do_cut(frame_num);
1262                 }
1263
1264 #if 0
1265                 // Reset every 100 frames, so that local variations in frame times
1266                 // (especially for the first few frames, when the shaders are
1267                 // compiled etc.) don't make it hard to measure for the entire
1268                 // remaining duration of the program.
1269                 if (frame == 10000) {
1270                         frame = 0;
1271                         start = now;
1272                 }
1273 #endif
1274                 check_error();
1275         }
1276
1277         resource_pool->clean_context();
1278 }
1279
1280 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
1281 {
1282         if (output_card_index != -1 && output_card_is_master) {
1283                 // The output card (ie., cards[output_card_index].output) is the master clock,
1284                 // so no input card (ie., cards[card_index].capture) is.
1285                 return false;
1286         }
1287         return (card_index == master_card_index);
1288 }
1289
1290 void Mixer::trim_queue(CaptureCard *card, size_t safe_queue_length)
1291 {
1292         // Count the number of frames in the queue, including any frames
1293         // we dropped. It's hard to know exactly how we should deal with
1294         // dropped (corrupted) input frames; they don't help our goal of
1295         // avoiding starvation, but they still add to the problem of latency.
1296         // Since dropped frames is going to mean a bump in the signal anyway,
1297         // we err on the side of having more stable latency instead.
1298         unsigned queue_length = 0;
1299         for (const CaptureCard::NewFrame &frame : card->new_frames) {
1300                 queue_length += frame.dropped_frames + 1;
1301         }
1302
1303         // If needed, drop frames until the queue is below the safe limit.
1304         // We prefer to drop from the head, because all else being equal,
1305         // we'd like more recent frames (less latency).
1306         unsigned dropped_frames = 0;
1307         while (queue_length > safe_queue_length) {
1308                 assert(!card->new_frames.empty());
1309                 assert(queue_length > card->new_frames.front().dropped_frames);
1310                 queue_length -= card->new_frames.front().dropped_frames;
1311
1312                 if (queue_length <= safe_queue_length) {
1313                         // No need to drop anything.
1314                         break;
1315                 }
1316
1317                 card->new_frames.pop_front();
1318                 card->new_frames_changed.notify_all();
1319                 --queue_length;
1320                 ++dropped_frames;
1321
1322                 if (queue_length == 0 && card->is_cef_capture) {
1323                         card->may_have_dropped_last_frame = true;
1324                 }
1325         }
1326
1327         card->metric_input_dropped_frames_jitter += dropped_frames;
1328         card->metric_input_queue_length_frames = queue_length;
1329
1330 #if 0
1331         if (dropped_frames > 0) {
1332                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
1333                         card_index, dropped_frames);
1334         }
1335 #endif
1336 }
1337
1338 pair<string, string> Mixer::get_channels_json()
1339 {
1340         Channels ret;
1341         for (int channel_idx = 0; channel_idx < theme->get_num_channels(); ++channel_idx) {
1342                 Channel *channel = ret.add_channel();
1343                 channel->set_index(channel_idx + 2);
1344                 channel->set_name(theme->get_channel_name(channel_idx + 2));
1345                 channel->set_color(theme->get_channel_color(channel_idx + 2));
1346         }
1347         string contents;
1348         google::protobuf::util::MessageToJsonString(ret, &contents);  // Ignore any errors.
1349         return make_pair(contents, "text/json");
1350 }
1351
1352 pair<string, string> Mixer::get_channel_color_http(unsigned channel_idx)
1353 {
1354         return make_pair(theme->get_channel_color(channel_idx), "text/plain");
1355 }
1356
1357 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])
1358 {
1359         OutputFrameInfo output_frame_info;
1360         constexpr steady_clock::duration master_card_timeout = milliseconds(200);
1361 start:
1362         unique_lock<mutex> lock(card_mutex, defer_lock);
1363         bool timed_out = false;
1364         if (master_card_is_output) {
1365                 // Clocked to the output, so wait for it to be ready for the next frame.
1366                 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);
1367                 lock.lock();
1368         } else {
1369                 // Wait for the master card to have a new frame.
1370                 output_frame_info.is_preroll = false;
1371                 lock.lock();
1372                 timed_out = !cards[master_card_index].new_frames_changed.wait_for(lock,
1373                         master_card_timeout,
1374                         [this, master_card_index] {
1375                                 return !cards[master_card_index].new_frames.empty() ||
1376                                         cards[master_card_index].capture == nullptr ||
1377                                         cards[master_card_index].capture->get_disconnected();
1378                         });
1379                 if (timed_out) {
1380                         fprintf(stderr, "WARNING: Master card (%s) did not deliver a frame for %u ms, creating a fake one.\n",
1381                                 description_for_card(master_card_index).c_str(),
1382                                 unsigned(duration_cast<milliseconds>(master_card_timeout).count()));
1383                 }
1384         }
1385
1386         if (timed_out) {
1387                 // The master card stalled for 200 ms (possible when it's e.g.
1388                 // an SRT card). Send a frame no matter what; this also makes sure
1389                 // any other cards get to empty their queues, and in general,
1390                 // that we make _some_ sort of forward progress.
1391                 handle_hotplugged_cards();
1392         } else if (master_card_is_output) {
1393                 handle_hotplugged_cards();
1394         } else if (cards[master_card_index].new_frames.empty()) {
1395                 // We were woken up, but not due to a new frame. Deal with it
1396                 // and then restart.
1397                 assert(cards[master_card_index].capture == nullptr ||
1398                        cards[master_card_index].capture->get_disconnected());
1399                 handle_hotplugged_cards();
1400                 lock.unlock();
1401                 goto start;
1402         }
1403
1404         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1405                 CaptureCard *card = &cards[card_index];
1406                 if (card->new_frames.empty()) {  // Starvation.
1407                         ++card->metric_input_duped_frames;
1408 #ifdef HAVE_CEF
1409                         if (card->is_cef_capture && card->may_have_dropped_last_frame) {
1410                                 // Unlike other sources, CEF is not guaranteed to send us a steady
1411                                 // stream of frames, so we'll have to ask it to repaint the frame
1412                                 // we dropped. (may_have_dropped_last_frame is set whenever we
1413                                 // trim the queue completely away, and cleared when we actually
1414                                 // get a new frame.)
1415                                 ((CEFCapture *)card->capture.get())->request_new_frame(/*ignore_if_locked=*/true);
1416                         }
1417 #endif
1418                 } else {
1419                         new_frames[card_index] = move(card->new_frames.front());
1420                         has_new_frame[card_index] = true;
1421                         card->new_frames.pop_front();
1422                         card->new_frames_changed.notify_all();
1423                 }
1424
1425                 raw_audio[card_index] = move(card->new_raw_audio);
1426         }
1427
1428         if (timed_out) {
1429                 // Pretend the frame happened a while ago and was only processed now,
1430                 // so that we get the duration sort-of right. This isn't ideal.
1431                 output_frame_info.dropped_frames = 0;  // Hard to define, really.
1432                 output_frame_info.frame_duration = lrint(TIMEBASE * duration<double>(master_card_timeout).count());
1433                 output_frame_info.frame_timestamp = steady_clock::now() - master_card_timeout;
1434         } else if (!master_card_is_output) {
1435                 output_frame_info.frame_timestamp = new_frames[master_card_index].received_timestamp;
1436                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
1437                 output_frame_info.frame_duration = new_frames[master_card_index].length;
1438         }
1439
1440         if (!output_frame_info.is_preroll) {
1441                 output_jitter_history.frame_arrived(output_frame_info.frame_timestamp, output_frame_info.frame_duration, output_frame_info.dropped_frames);
1442         }
1443
1444         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1445                 CaptureCard *card = &cards[card_index];
1446                 if (has_new_frame[card_index] &&
1447                     !input_card_is_master_clock(card_index, master_card_index) &&
1448                     !output_frame_info.is_preroll) {
1449                         card->queue_length_policy.update_policy(
1450                                 output_frame_info.frame_timestamp,
1451                                 card->jitter_history.get_expected_next_frame(),
1452                                 new_frames[master_card_index].length,
1453                                 output_frame_info.frame_duration,
1454                                 card->jitter_history.estimate_max_jitter(),
1455                                 output_jitter_history.estimate_max_jitter());
1456                         trim_queue(card, min<int>(global_flags.max_input_queue_frames,
1457                                                   card->queue_length_policy.get_safe_queue_length()));
1458                 }
1459         }
1460
1461         // This might get off by a fractional sample when changing master card
1462         // between ones with different frame rates, but that's fine.
1463         int64_t num_samples_times_timebase = int64_t(OUTPUT_FREQUENCY) * output_frame_info.frame_duration + fractional_samples;
1464         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
1465         fractional_samples = num_samples_times_timebase % TIMEBASE;
1466         assert(output_frame_info.num_samples >= 0);
1467
1468         if (timed_out) {
1469                 DeviceSpec device{InputSourceType::CAPTURE_CARD, master_card_index};
1470                 bool success;
1471                 do {
1472                         success = audio_mixer->add_silence(device, output_frame_info.num_samples, /*dropped_frames=*/0);
1473                 } while (!success);
1474         }
1475
1476         return output_frame_info;
1477 }
1478
1479 void Mixer::handle_hotplugged_cards()
1480 {
1481         // Check for cards that have been disconnected since last frame.
1482         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1483                 CaptureCard *card = &cards[card_index];
1484                 if (card->capture != nullptr && card->capture->get_disconnected()) {
1485                         bool is_active = card_index < unsigned(global_flags.min_num_cards) || cards[card_index].force_active;
1486                         if (is_active) {
1487                                 fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
1488                                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1489                                 configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
1490                                 card->jitter_history.clear();
1491                                 card->capture->start_bm_capture();
1492                         } else {
1493                                 // NOTE: The theme might end up forcing the card back at some later point
1494                                 // (ie., force_active is false now, but might immediately be true again on
1495                                 // e.g. the next frame). That should be rare, though, so we don't bother
1496                                 // adjusting the message.
1497                                 fprintf(stderr, "Card %u went away, removing. (To keep a fake card, increase --num-cards.)\n", card_index);
1498                                 theme->remove_card(card_index);
1499                                 configure_card(card_index, /*capture=*/nullptr, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
1500                                 card->jitter_history.clear();
1501                         }
1502                 }
1503         }
1504
1505         // Count how many active cards we already have. Used below to check that we
1506         // don't go past the max_cards limit set by the user. Note that (non-SRT) video
1507         // and HTML “cards” don't count towards this limit.
1508         int num_video_cards = 0;
1509         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1510                 CaptureCard *card = &cards[card_index];
1511                 if (card->type == CardType::LIVE_CARD || is_srt_card(card)) {
1512                         ++num_video_cards;
1513                 }
1514         }
1515
1516         // Check for cards that have been connected since last frame.
1517         vector<libusb_device *> hotplugged_cards_copy;
1518 #ifdef HAVE_SRT
1519         vector<int> hotplugged_srt_cards_copy;
1520 #endif
1521         {
1522                 lock_guard<mutex> lock(hotplug_mutex);
1523                 swap(hotplugged_cards, hotplugged_cards_copy);
1524 #ifdef HAVE_SRT
1525                 swap(hotplugged_srt_cards, hotplugged_srt_cards_copy);
1526 #endif
1527         }
1528         for (libusb_device *new_dev : hotplugged_cards_copy) {
1529                 // Look for a fake capture card where we can stick this in.
1530                 int free_card_index = -1;
1531                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1532                         if (cards[card_index].is_fake_capture) {
1533                                 free_card_index = card_index;
1534                                 break;
1535                         }
1536                 }
1537
1538                 if (free_card_index == -1 || num_video_cards >= global_flags.max_num_cards) {
1539                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
1540                         libusb_unref_device(new_dev);
1541                 } else {
1542                         // BMUSBCapture takes ownership.
1543                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
1544                         CaptureCard *card = &cards[free_card_index];
1545                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
1546                         configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr, /*is_srt_card=*/false);
1547                         card->jitter_history.clear();
1548                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1549                         capture->start_bm_capture();
1550                 }
1551         }
1552
1553 #ifdef HAVE_SRT
1554         // Same, for SRT inputs.
1555         for (SRTSOCKET sock : hotplugged_srt_cards_copy) {
1556                 char name[256];
1557                 int namelen = sizeof(name);
1558                 srt_getsockopt(sock, /*ignored=*/0, SRTO_STREAMID, name, &namelen);
1559                 string stream_id(name, namelen);
1560
1561                 // Look for a fake capture card where we can stick this in.
1562                 // Prioritize ones that previously held SRT streams with the
1563                 // same stream ID, if any exist -- and it multiple exist,
1564                 // take the one that disconnected the last.
1565                 int first_free_card_index = -1, last_matching_free_card_index = -1;
1566                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1567                         CaptureCard *card = &cards[card_index];
1568                         if (!card->is_fake_capture) {
1569                                 continue;
1570                         }
1571                         if (first_free_card_index == -1) {
1572                                 first_free_card_index = card_index;
1573                         }
1574                         if (card->last_srt_stream_id == stream_id &&
1575                             (last_matching_free_card_index == -1 ||
1576                              card->fake_capture_counter >
1577                                 cards[last_matching_free_card_index].fake_capture_counter)) {
1578                                 last_matching_free_card_index = card_index;
1579                         }
1580                 }
1581
1582                 const int free_card_index = (last_matching_free_card_index != -1)
1583                         ? last_matching_free_card_index : first_free_card_index;
1584                 if (free_card_index == -1 || num_video_cards >= global_flags.max_num_cards) {
1585                         if (stream_id.empty()) {
1586                                 stream_id = "no name";
1587                         }
1588                         fprintf(stderr, "New SRT stream connected (%s), but no free slots -- ignoring.\n", stream_id.c_str());
1589                         srt_close(sock);
1590                 } else {
1591                         // FFmpegCapture takes ownership.
1592                         if (stream_id.empty()) {
1593                                 fprintf(stderr, "New unnamed SRT stream connected, choosing slot %d.\n", free_card_index);
1594                         } else {
1595                                 fprintf(stderr, "New SRT stream connected (%s), choosing slot %d.\n", stream_id.c_str(), free_card_index);
1596                         }
1597                         CaptureCard *card = &cards[free_card_index];
1598                         FFmpegCapture *capture = new FFmpegCapture(sock, stream_id);
1599                         capture->set_card_index(free_card_index);
1600                         configure_card(free_card_index, capture, CardType::FFMPEG_INPUT, /*output=*/nullptr, /*is_srt_card=*/true);
1601                         card->srt_metrics.update_srt_stats(sock);  // Initial zero stats.
1602                         card->last_srt_stream_id = stream_id;
1603                         card->jitter_history.clear();
1604                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1605                         capture->start_bm_capture();
1606                 }
1607         }
1608 #endif
1609
1610         // Finally, newly forced-to-active fake capture cards.
1611         for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1612                 CaptureCard *card = &cards[card_index];
1613                 if (card->capture == nullptr && card->force_active) {
1614                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1615                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr, /*is_srt_card=*/false);
1616                         card->jitter_history.clear();
1617                         card->capture->start_bm_capture();
1618                 }
1619         }
1620 }
1621
1622
1623 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)
1624 {
1625         // Resample the audio as needed, including from previously dropped frames.
1626         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
1627                 const bool dropped_frame = (frame_num != dropped_frames);
1628                 {
1629                         // Signal to the audio thread to process this frame.
1630                         // Note that if the frame is a dropped frame, we signal that
1631                         // we don't want to use this frame as base for adjusting
1632                         // the resampler rate. The reason for this is that the timing
1633                         // of these frames is often way too late; they typically don't
1634                         // “arrive” before we synthesize them. Thus, we could end up
1635                         // in a situation where we have inserted e.g. five audio frames
1636                         // into the queue before we then start pulling five of them
1637                         // back out. This makes ResamplingQueue overestimate the delay,
1638                         // causing undue resampler changes. (We _do_ use the last,
1639                         // non-dropped frame; perhaps we should just discard that as well,
1640                         // since dropped frames are expected to be rare, and it might be
1641                         // better to just wait until we have a slightly more normal situation).
1642                         lock_guard<mutex> lock(audio_mutex);
1643                         bool adjust_rate = !dropped_frame && !is_preroll;
1644                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
1645                         audio_task_queue_changed.notify_one();
1646                 }
1647                 if (dropped_frame) {
1648                         // For dropped frames, increase the pts. Note that if the format changed
1649                         // in the meantime, we have no way of detecting that; we just have to
1650                         // assume the frame length is always the same.
1651                         pts_int += length_per_frame;
1652                 }
1653         }
1654 }
1655
1656 void Mixer::render_one_frame(int64_t duration)
1657 {
1658         // Determine the time code for this frame before we start rendering.
1659         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1660         if (display_timecode_on_stdout) {
1661                 printf("Timecode: '%s'\n", timecode_text.c_str());
1662         }
1663
1664         // Update Y'CbCr settings for all cards.
1665         {
1666                 lock_guard<mutex> lock(card_mutex);
1667                 for (unsigned card_index = 0; card_index < MAX_VIDEO_CARDS; ++card_index) {
1668                         YCbCrInterpretation *interpretation = &ycbcr_interpretation[card_index];
1669                         input_state.ycbcr_coefficients_auto[card_index] = interpretation->ycbcr_coefficients_auto;
1670                         input_state.ycbcr_coefficients[card_index] = interpretation->ycbcr_coefficients;
1671                         input_state.full_range[card_index] = interpretation->full_range;
1672                 }
1673         }
1674
1675         // Get the main chain from the theme, and set its state immediately.
1676         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1677         EffectChain *chain = theme_main_chain.chain;
1678         theme_main_chain.setup_chain();
1679         //theme_main_chain.chain->enable_phase_timing(true);
1680
1681         // If HDMI/SDI output is active and the user has requested auto mode,
1682         // its mode overrides the existing Y'CbCr setting for the chain.
1683         YCbCrLumaCoefficients ycbcr_output_coefficients;
1684         if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
1685                 ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
1686         } else {
1687                 ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
1688         }
1689
1690         // TODO: Reduce the duplication against theme.cpp.
1691         YCbCrFormat output_ycbcr_format;
1692         output_ycbcr_format.chroma_subsampling_x = 1;
1693         output_ycbcr_format.chroma_subsampling_y = 1;
1694         output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
1695         output_ycbcr_format.full_range = false;
1696         output_ycbcr_format.num_levels = 1 << global_flags.bit_depth;
1697         chain->change_ycbcr_output_format(output_ycbcr_format);
1698
1699         // Render main chain. If we're using zerocopy Quick Sync encoding
1700         // (the default case), we take an extra copy of the created outputs,
1701         // so that we can display it back to the screen later (it's less memory
1702         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1703         // Ideally, we'd like to avoid taking copies and just use the main textures
1704         // for display as well, but they're just views into VA-API memory and must be
1705         // unmapped during encoding, so we can't use them for display, unfortunately.
1706         GLuint y_tex, cbcr_full_tex, cbcr_tex;
1707         GLuint y_copy_tex, cbcr_copy_tex = 0;
1708         GLuint y_display_tex, cbcr_display_tex;
1709         GLenum y_type = (global_flags.bit_depth > 8) ? GL_R16 : GL_R8;
1710         GLenum cbcr_type = (global_flags.bit_depth > 8) ? GL_RG16 : GL_RG8;
1711         const bool is_zerocopy = video_encoder->is_zerocopy();
1712         if (is_zerocopy) {
1713                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1714                 y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1715                 cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1716
1717                 y_display_tex = y_copy_tex;
1718                 cbcr_display_tex = cbcr_copy_tex;
1719
1720                 // y_tex and cbcr_tex will be given by VideoEncoder.
1721         } else {
1722                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1723                 y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1724                 cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1725
1726                 y_display_tex = y_tex;
1727                 cbcr_display_tex = cbcr_tex;
1728         }
1729
1730         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1731         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1732         assert(got_frame);
1733
1734         GLuint fbo;
1735         if (is_zerocopy) {
1736                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1737         } else {
1738                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
1739         }
1740         check_error();
1741         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1742
1743         if (display_timecode_in_stream) {
1744                 // Render the timecode on top.
1745                 timecode_renderer->render_timecode(fbo, timecode_text);
1746         }
1747
1748         resource_pool->release_fbo(fbo);
1749
1750         if (is_zerocopy) {
1751                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1752         } else {
1753                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1754         }
1755         if (output_card_index != -1) {
1756                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
1757         }
1758         resource_pool->release_2d_texture(cbcr_full_tex);
1759
1760         // Set the right state for the Y' and CbCr textures we use for display.
1761         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1762         glBindTexture(GL_TEXTURE_2D, y_display_tex);
1763         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1764         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1765         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1766
1767         glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
1768         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1769         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1770         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1771
1772         RefCountedGLsync fence = video_encoder->end_frame();
1773
1774         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1775         // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
1776         DisplayFrame live_frame;
1777         live_frame.chain = display_chain.get();
1778         live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
1779                 display_input->set_texture_num(0, y_display_tex);
1780                 display_input->set_texture_num(1, cbcr_display_tex);
1781         };
1782         live_frame.ready_fence = fence;
1783         live_frame.input_frames = {};
1784         live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
1785         output_channel[OUTPUT_LIVE].output_frame(move(live_frame));
1786
1787         // Set up preview and any additional channels.
1788         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1789                 DisplayFrame display_frame;
1790                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1791                 display_frame.chain = move(chain.chain);
1792                 display_frame.setup_chain = move(chain.setup_chain);
1793                 display_frame.ready_fence = fence;
1794                 display_frame.input_frames = move(chain.input_frames);
1795                 display_frame.temp_textures = {};
1796                 output_channel[i].output_frame(move(display_frame));
1797         }
1798 }
1799
1800 void Mixer::audio_thread_func()
1801 {
1802         pthread_setname_np(pthread_self(), "Mixer_Audio");
1803
1804         while (!should_quit) {
1805                 AudioTask task;
1806
1807                 {
1808                         unique_lock<mutex> lock(audio_mutex);
1809                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1810                         if (should_quit) {
1811                                 return;
1812                         }
1813                         task = audio_task_queue.front();
1814                         audio_task_queue.pop();
1815                 }
1816
1817                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1818                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1819                 vector<float> samples_out = audio_mixer->get_output(
1820                         task.frame_timestamp,
1821                         task.num_samples,
1822                         rate_adjustment_policy);
1823
1824                 // Send the samples to the sound card, then add them to the output.
1825                 if (alsa) {
1826                         alsa->write(samples_out);
1827                 }
1828                 if (output_card_index != -1) {
1829                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1830                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1831                 }
1832                 video_encoder->add_audio(task.pts_int, move(samples_out));
1833         }
1834 }
1835
1836 void Mixer::release_display_frame(DisplayFrame *frame)
1837 {
1838         for (GLuint texnum : frame->temp_textures) {
1839                 resource_pool->release_2d_texture(texnum);
1840         }
1841         frame->temp_textures.clear();
1842         frame->ready_fence.reset();
1843         frame->input_frames.clear();
1844 }
1845
1846 void Mixer::start()
1847 {
1848         mixer_thread = thread(&Mixer::thread_func, this);
1849         audio_thread = thread(&Mixer::audio_thread_func, this);
1850 }
1851
1852 void Mixer::quit()
1853 {
1854         should_quit = true;
1855         audio_task_queue_changed.notify_one();
1856         mixer_thread.join();
1857         audio_thread.join();
1858 #ifdef HAVE_SRT
1859         if (global_flags.srt_port >= 0) {
1860                 // There's seemingly no other reasonable way to wake up the thread
1861                 // (libsrt's epoll equivalent is busy-waiting).
1862                 int sock = srt_create_socket();
1863                 if (sock != -1) {
1864                         sockaddr_in6 addr;
1865                         memset(&addr, 0, sizeof(addr));
1866                         addr.sin6_family = AF_INET6;
1867                         addr.sin6_addr = IN6ADDR_LOOPBACK_INIT;
1868                         addr.sin6_port = htons(global_flags.srt_port);
1869                         srt_connect(sock, (sockaddr *)&addr, sizeof(addr));
1870                         srt_close(sock);
1871                 }
1872                 srt_thread.join();
1873         }
1874 #endif
1875 }
1876
1877 void Mixer::transition_clicked(int transition_num)
1878 {
1879         theme->transition_clicked(transition_num, pts());
1880 }
1881
1882 void Mixer::channel_clicked(int preview_num)
1883 {
1884         theme->channel_clicked(preview_num);
1885 }
1886
1887 YCbCrInterpretation Mixer::get_input_ycbcr_interpretation(unsigned card_index) const
1888 {
1889         lock_guard<mutex> lock(card_mutex);
1890         return ycbcr_interpretation[card_index];
1891 }
1892
1893 void Mixer::set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation)
1894 {
1895         lock_guard<mutex> lock(card_mutex);
1896         ycbcr_interpretation[card_index] = interpretation;
1897 }
1898
1899 void Mixer::start_mode_scanning(unsigned card_index)
1900 {
1901         assert(card_index < MAX_VIDEO_CARDS);
1902         if (cards[card_index].capture == nullptr) {
1903                 // Inactive card. Should never happen.
1904                 return;
1905         }
1906         if (is_mode_scanning[card_index]) {
1907                 return;
1908         }
1909         is_mode_scanning[card_index] = true;
1910         mode_scanlist[card_index].clear();
1911         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1912                 mode_scanlist[card_index].push_back(mode.first);
1913         }
1914         assert(!mode_scanlist[card_index].empty());
1915         mode_scanlist_index[card_index] = 0;
1916         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1917         last_mode_scan_change[card_index] = steady_clock::now();
1918 }
1919
1920 map<uint32_t, VideoMode> Mixer::get_available_output_video_modes() const
1921 {
1922         assert(desired_output_card_index != -1);
1923         lock_guard<mutex> lock(card_mutex);
1924         return cards[desired_output_card_index].output->get_available_video_modes();
1925 }
1926
1927 string Mixer::get_ffmpeg_filename(unsigned card_index) const
1928 {
1929         assert(card_index < MAX_VIDEO_CARDS);
1930         assert(cards[card_index].type == CardType::FFMPEG_INPUT);
1931         return ((FFmpegCapture *)(cards[card_index].capture.get()))->get_filename();
1932 }
1933
1934 void Mixer::set_ffmpeg_filename(unsigned card_index, const string &filename) {
1935         assert(card_index < MAX_VIDEO_CARDS);
1936         assert(cards[card_index].type == CardType::FFMPEG_INPUT);
1937         ((FFmpegCapture *)(cards[card_index].capture.get()))->change_filename(filename);
1938 }
1939
1940 void Mixer::wait_for_next_frame()
1941 {
1942         unique_lock<mutex> lock(frame_num_mutex);
1943         unsigned old_frame_num = frame_num;
1944         frame_num_updated.wait_for(lock, seconds(1),  // Timeout is just in case.
1945                 [old_frame_num, this]{ return this->frame_num > old_frame_num; });
1946 }
1947
1948 Mixer::OutputChannel::~OutputChannel()
1949 {
1950         if (has_current_frame) {
1951                 parent->release_display_frame(&current_frame);
1952         }
1953         if (has_ready_frame) {
1954                 parent->release_display_frame(&ready_frame);
1955         }
1956 }
1957
1958 void Mixer::OutputChannel::output_frame(DisplayFrame &&frame)
1959 {
1960         // Store this frame for display. Remove the ready frame if any
1961         // (it was seemingly never used).
1962         {
1963                 lock_guard<mutex> lock(frame_mutex);
1964                 if (has_ready_frame) {
1965                         parent->release_display_frame(&ready_frame);
1966                 }
1967                 ready_frame = move(frame);
1968                 has_ready_frame = true;
1969
1970                 // Call the callbacks under the mutex (they should be short),
1971                 // so that we don't race against a callback removal.
1972                 for (const auto &key_and_callback : new_frame_ready_callbacks) {
1973                         key_and_callback.second();
1974                 }
1975         }
1976
1977         // Reduce the number of callbacks by filtering duplicates. The reason
1978         // why we bother doing this is that Qt seemingly can get into a state
1979         // where its builds up an essentially unbounded queue of signals,
1980         // consuming more and more memory, and there's no good way of collapsing
1981         // user-defined signals or limiting the length of the queue.
1982         if (transition_names_updated_callback) {
1983                 vector<string> transition_names = global_mixer->get_transition_names();
1984                 bool changed = false;
1985                 if (transition_names.size() != last_transition_names.size()) {
1986                         changed = true;
1987                 } else {
1988                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1989                                 if (transition_names[i] != last_transition_names[i]) {
1990                                         changed = true;
1991                                         break;
1992                                 }
1993                         }
1994                 }
1995                 if (changed) {
1996                         transition_names_updated_callback(transition_names);
1997                         last_transition_names = transition_names;
1998                 }
1999         }
2000         if (name_updated_callback) {
2001                 string name = global_mixer->get_channel_name(channel);
2002                 if (name != last_name) {
2003                         name_updated_callback(name);
2004                         last_name = name;
2005                 }
2006         }
2007         if (color_updated_callback) {
2008                 string color = global_mixer->get_channel_color(channel);
2009                 if (color != last_color) {
2010                         color_updated_callback(color);
2011                         last_color = color;
2012                 }
2013         }
2014 }
2015
2016 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
2017 {
2018         lock_guard<mutex> lock(frame_mutex);
2019         if (!has_current_frame && !has_ready_frame) {
2020                 return false;
2021         }
2022
2023         if (has_current_frame && has_ready_frame) {
2024                 // We have a new ready frame. Toss the current one.
2025                 parent->release_display_frame(&current_frame);
2026                 has_current_frame = false;
2027         }
2028         if (has_ready_frame) {
2029                 assert(!has_current_frame);
2030                 current_frame = move(ready_frame);
2031                 ready_frame.ready_fence.reset();  // Drop the refcount.
2032                 ready_frame.input_frames.clear();  // Drop the refcounts.
2033                 has_current_frame = true;
2034                 has_ready_frame = false;
2035         }
2036
2037         *frame = current_frame;
2038         return true;
2039 }
2040
2041 void Mixer::OutputChannel::add_frame_ready_callback(void *key, Mixer::new_frame_ready_callback_t callback)
2042 {
2043         lock_guard<mutex> lock(frame_mutex);
2044         new_frame_ready_callbacks[key] = callback;
2045 }
2046
2047 void Mixer::OutputChannel::remove_frame_ready_callback(void *key)
2048 {
2049         lock_guard<mutex> lock(frame_mutex);
2050         new_frame_ready_callbacks.erase(key);
2051 }
2052
2053 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
2054 {
2055         transition_names_updated_callback = callback;
2056 }
2057
2058 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
2059 {
2060         name_updated_callback = callback;
2061 }
2062
2063 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
2064 {
2065         color_updated_callback = callback;
2066 }
2067
2068 #ifdef HAVE_SRT
2069 void Mixer::start_srt()
2070 {
2071         SRTSOCKET sock = srt_create_socket();
2072         sockaddr_in6 addr;
2073         memset(&addr, 0, sizeof(addr));
2074         addr.sin6_family = AF_INET6;
2075         addr.sin6_port = htons(global_flags.srt_port);
2076
2077         int zero = 0;
2078         int err = srt_setsockopt(sock, /*level=*/0, SRTO_IPV6ONLY, &zero, sizeof(zero));
2079         if (err != 0) {
2080                 fprintf(stderr, "srt_setsockopt(SRTO_IPV6ONLY): %s\n", srt_getlasterror_str());
2081                 abort();
2082         }
2083         err = srt_bind(sock, (sockaddr *)&addr, sizeof(addr));
2084         if (err != 0) {
2085                 fprintf(stderr, "srt_bind: %s\n", srt_getlasterror_str());
2086                 abort();
2087         }
2088         err = srt_listen(sock, MAX_VIDEO_CARDS);
2089         if (err != 0) {
2090                 fprintf(stderr, "srt_listen: %s\n", srt_getlasterror_str());
2091                 abort();
2092         }
2093
2094         srt_thread = thread([this, sock] {
2095                 sockaddr_in6 addr;
2096                 for ( ;; ) {
2097                         int sa_len = sizeof(addr);
2098                         int clientsock = srt_accept(sock, (sockaddr *)&addr, &sa_len);
2099                         if (should_quit) {
2100                                 if (clientsock != -1) {
2101                                         srt_close(clientsock);
2102                                 }
2103                                 break;
2104                         }
2105                         if (!global_flags.enable_srt) {  // Runtime UI toggle.
2106                                 // Perhaps not as good as never listening in the first place,
2107                                 // but much simpler to turn on and off.
2108                                 srt_close(clientsock);
2109                                 continue;
2110                         }
2111                         lock_guard<mutex> lock(hotplug_mutex);
2112                         hotplugged_srt_cards.push_back(clientsock);
2113                 }
2114                 srt_close(sock);
2115         });
2116 }
2117 #endif
2118
2119 string Mixer::description_for_card(unsigned card_index)
2120 {
2121         CaptureCard *card = &cards[card_index];
2122         if (card->capture == nullptr) {
2123                 // Should never be called for inactive cards, but OK.
2124                 char buf[256];
2125                 snprintf(buf, sizeof(buf), "Inactive capture card %u", card_index);
2126                 return buf;
2127         }
2128         if (card->type != CardType::FFMPEG_INPUT) {
2129                 char buf[256];
2130                 snprintf(buf, sizeof(buf), "Capture card %u (%s)", card_index, card->capture->get_description().c_str());
2131                 return buf;
2132         }
2133
2134         // Number (non-SRT) FFmpeg inputs from zero, separately from the capture cards,
2135         // since it's not too obvious for the user that they are “cards”.
2136         unsigned ffmpeg_index = 0;
2137         for (unsigned i = 0; i < card_index; ++i) {
2138                 CaptureCard *other_card = &cards[i];
2139                 if (other_card->type == CardType::FFMPEG_INPUT && !is_srt_card(other_card)) {
2140                         ++ffmpeg_index;
2141                 }
2142         }
2143         char buf[256];
2144         snprintf(buf, sizeof(buf), "Video input %u (%s)", ffmpeg_index, card->capture->get_description().c_str());
2145         return buf;
2146 }
2147
2148 bool Mixer::is_srt_card(const Mixer::CaptureCard *card)
2149 {
2150 #ifdef HAVE_SRT
2151         if (card->type == CardType::FFMPEG_INPUT) {
2152                 int srt_sock = static_cast<FFmpegCapture *>(card->capture.get())->get_srt_sock();
2153                 return srt_sock != -1;
2154         }
2155 #endif
2156         return false;
2157 }
2158
2159 mutex RefCountedGLsync::fence_lock;