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

   1 #undef Success
   2
   3 #include "mixer.h"
   4
   5 #include <assert.h>
   6 #include <epoxy/egl.h>
   7 #include <movit/effect_chain.h>
   8 #include <movit/effect_util.h>
   9 #include <movit/flat_input.h>
  10 #include <movit/image_format.h>
  11 #include <movit/init.h>
  12 #include <movit/resource_pool.h>
  13 #include <pthread.h>
  14 #include <stdint.h>
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <algorithm>
  18 #include <chrono>
  19 #include <condition_variable>
  20 #include <cstddef>
  21 #include <cstdint>
  22 #include <memory>
  23 #include <mutex>
  24 #include <ratio>
  25 #include <string>
  26 #include <thread>
  27 #include <utility>
  28 #include <vector>
  29
  30 #include "DeckLinkAPI.h"
  31 #include "LinuxCOM.h"
  32 #include "alsa_output.h"
  33 #include "basic_stats.h"
  34 #include "bmusb/bmusb.h"
  35 #include "bmusb/fake_capture.h"
  36 #ifdef HAVE_CEF
  37 #include "cef_capture.h"
  38 #endif
  39 #include "chroma_subsampler.h"
  40 #include "context.h"
  41 #include "decklink_capture.h"
  42 #include "decklink_output.h"
  43 #include "defs.h"
  44 #include "disk_space_estimator.h"
  45 #include "ffmpeg_capture.h"
  46 #include "flags.h"
  47 #include "input_mapping.h"
  48 #include "metrics.h"
  49 #include "pbo_frame_allocator.h"
  50 #include "ref_counted_gl_sync.h"
  51 #include "resampling_queue.h"
  52 #include "timebase.h"
  53 #include "timecode_renderer.h"
  54 #include "v210_converter.h"
  55 #include "video_encoder.h"
  56
  57 #undef Status
  58 #include <google/protobuf/util/json_util.h>
  59 #include "json.pb.h"
  60
  61 class IDeckLink;
  62 class QOpenGLContext;
  63
  64 using namespace movit;
  65 using namespace std;
  66 using namespace std::chrono;
  67 using namespace std::placeholders;
  68 using namespace bmusb;
  69
  70 Mixer *global_mixer = nullptr;
  71
  72 namespace {
  73
  74 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  75 {
  76         if (interlaced) {
  77                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  78                         input_state->buffered_frames[card_index][frame_num] =
  79                                 input_state->buffered_frames[card_index][frame_num - 1];
  80                 }
  81                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  82         } else {
  83                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  84                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  85                 }
  86         }
  87 }
  88
  89 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned cbcr_width, unsigned cbcr_height, unsigned v210_width)
  90 {
  91         bool first;
  92         switch (userdata->pixel_format) {
  93         case PixelFormat_10BitYCbCr:
  94                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
  95                 break;
  96         case PixelFormat_8BitYCbCr:
  97                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
  98                 break;
  99         case PixelFormat_8BitBGRA:
 100                 first = userdata->tex_rgba[field] == 0;
 101                 break;
 102         case PixelFormat_8BitYCbCrPlanar:
 103                 first = userdata->tex_y[field] == 0 || userdata->tex_cb[field] == 0 || userdata->tex_cr[field] == 0;
 104                 break;
 105         default:
 106                 assert(false);
 107         }
 108
 109         if (first ||
 110             width != userdata->last_width[field] ||
 111             height != userdata->last_height[field] ||
 112             cbcr_width != userdata->last_cbcr_width[field] ||
 113             cbcr_height != userdata->last_cbcr_height[field]) {
 114                 // We changed resolution since last use of this texture, so we need to create
 115                 // a new object. Note that this each card has its own PBOFrameAllocator,
 116                 // we don't need to worry about these flip-flopping between resolutions.
 117                 switch (userdata->pixel_format) {
 118                 case PixelFormat_10BitYCbCr:
 119                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
 120                         check_error();
 121                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 122                         check_error();
 123                         break;
 124                 case PixelFormat_8BitYCbCr: {
 125                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 126                         check_error();
 127                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 128                         check_error();
 129                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 130                         check_error();
 131                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 132                         check_error();
 133                         break;
 134                 }
 135                 case PixelFormat_8BitYCbCrPlanar: {
 136                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 137                         check_error();
 138                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 139                         check_error();
 140                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cb[field]);
 141                         check_error();
 142                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 143                         check_error();
 144                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cr[field]);
 145                         check_error();
 146                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 147                         check_error();
 148                         break;
 149                 }
 150                 case PixelFormat_8BitBGRA:
 151                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
 152                         check_error();
 153                         if (global_flags.can_disable_srgb_decoder) {  // See the comments in tweaked_inputs.h.
 154                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
 155                         } else {
 156                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
 157                         }
 158                         check_error();
 159                         break;
 160                 default:
 161                         assert(false);
 162                 }
 163                 userdata->last_width[field] = width;
 164                 userdata->last_height[field] = height;
 165                 userdata->last_cbcr_width[field] = cbcr_width;
 166                 userdata->last_cbcr_height[field] = cbcr_height;
 167         }
 168         if (global_flags.ten_bit_input &&
 169             (first || v210_width != userdata->last_v210_width[field])) {
 170                 // Same as above; we need to recreate the texture.
 171                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
 172                 check_error();
 173                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 174                 check_error();
 175                 userdata->last_v210_width[field] = v210_width;
 176         }
 177 }
 178
 179 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
 180 {
 181         if (interlaced_stride) {
 182                 stride *= 2;
 183         }
 184         if (global_flags.flush_pbos) {
 185                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
 186                 check_error();
 187         }
 188
 189         glBindTexture(GL_TEXTURE_2D, tex);
 190         check_error();
 191         if (interlaced_stride) {
 192                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
 193                 check_error();
 194         } else {
 195                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 196                 check_error();
 197         }
 198
 199         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
 200         check_error();
 201         glBindTexture(GL_TEXTURE_2D, 0);
 202         check_error();
 203         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 204         check_error();
 205 }
 206
 207 }  // namespace
 208
 209 void JitterHistory::register_metrics(const vector<pair<string, string>> &labels)
 210 {
 211         global_metrics.add("input_underestimated_jitter_frames", labels, &metric_input_underestimated_jitter_frames);
 212         global_metrics.add("input_estimated_max_jitter_seconds", labels, &metric_input_estimated_max_jitter_seconds, Metrics::TYPE_GAUGE);
 213 }
 214
 215 void JitterHistory::unregister_metrics(const vector<pair<string, string>> &labels)
 216 {
 217         global_metrics.remove("input_underestimated_jitter_frames", labels);
 218         global_metrics.remove("input_estimated_max_jitter_seconds", labels);
 219 }
 220
 221 void JitterHistory::frame_arrived(steady_clock::time_point now, int64_t frame_duration, size_t dropped_frames)
 222 {
 223         if (expected_timestamp > steady_clock::time_point::min()) {
 224                 expected_timestamp += dropped_frames * nanoseconds(frame_duration * 1000000000 / TIMEBASE);
 225                 double jitter_seconds = fabs(duration<double>(expected_timestamp - now).count());
 226                 history.push_back(orders.insert(jitter_seconds));
 227                 if (jitter_seconds > estimate_max_jitter()) {
 228                         ++metric_input_underestimated_jitter_frames;
 229                 }
 230
 231                 metric_input_estimated_max_jitter_seconds = estimate_max_jitter();
 232
 233                 if (history.size() > history_length) {
 234                         orders.erase(history.front());
 235                         history.pop_front();
 236                 }
 237                 assert(history.size() <= history_length);
 238         }
 239         expected_timestamp = now + nanoseconds(frame_duration * 1000000000 / TIMEBASE);
 240 }
 241
 242 double JitterHistory::estimate_max_jitter() const
 243 {
 244         if (orders.empty()) {
 245                 return 0.0;
 246         }
 247         size_t elem_idx = lrint((orders.size() - 1) * percentile);
 248         if (percentile <= 0.5) {
 249                 return *next(orders.begin(), elem_idx) * multiplier;
 250         } else {
 251                 return *prev(orders.end(), orders.size() - elem_idx) * multiplier;
 252         }
 253 }
 254
 255 void QueueLengthPolicy::register_metrics(const vector<pair<string, string>> &labels)
 256 {
 257         global_metrics.add("input_queue_safe_length_frames", labels, &metric_input_queue_safe_length_frames, Metrics::TYPE_GAUGE);
 258 }
 259
 260 void QueueLengthPolicy::unregister_metrics(const vector<pair<string, string>> &labels)
 261 {
 262         global_metrics.remove("input_queue_safe_length_frames", labels);
 263 }
 264
 265 void QueueLengthPolicy::update_policy(steady_clock::time_point now,
 266                                       steady_clock::time_point expected_next_frame,
 267                                       int64_t input_frame_duration,
 268                                       int64_t master_frame_duration,
 269                                       double max_input_card_jitter_seconds,
 270                                       double max_master_card_jitter_seconds)
 271 {
 272         double input_frame_duration_seconds = input_frame_duration / double(TIMEBASE);
 273         double master_frame_duration_seconds = master_frame_duration / double(TIMEBASE);
 274
 275         // Figure out when we can expect the next frame for this card, assuming
 276         // worst-case jitter (ie., the frame is maximally late).
 277         double seconds_until_next_frame = max(duration<double>(expected_next_frame - now).count() + max_input_card_jitter_seconds, 0.0);
 278
 279         // How many times are the master card expected to tick in that time?
 280         // We assume the master clock has worst-case jitter but not any rate
 281         // discrepancy, ie., it ticks as early as possible every time, but not
 282         // cumulatively.
 283         double frames_needed = (seconds_until_next_frame + max_master_card_jitter_seconds) / master_frame_duration_seconds;
 284
 285         // As a special case, if the master card ticks faster than the input card,
 286         // we expect the queue to drain by itself even without dropping. But if
 287         // the difference is small (e.g. 60 Hz master and 59.94 input), it would
 288         // go slowly enough that the effect wouldn't really be appreciable.
 289         // We account for this by looking at the situation five frames ahead,
 290         // assuming everything else is the same.
 291         double frames_allowed;
 292         if (master_frame_duration < input_frame_duration) {
 293                 frames_allowed = frames_needed + 5 * (input_frame_duration_seconds - master_frame_duration_seconds) / master_frame_duration_seconds;
 294         } else {
 295                 frames_allowed = frames_needed;
 296         }
 297
 298         safe_queue_length = max<int>(floor(frames_allowed), 0);
 299         metric_input_queue_safe_length_frames = safe_queue_length;
 300 }
 301
 302 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 303         : httpd(),
 304           num_cards(num_cards),
 305           mixer_surface(create_surface(format)),
 306           h264_encoder_surface(create_surface(format)),
 307           decklink_output_surface(create_surface(format))
 308 {
 309         memcpy(ycbcr_interpretation, global_flags.ycbcr_interpretation, sizeof(ycbcr_interpretation));
 310         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 311         check_error();
 312
 313         // This nearly always should be true.
 314         global_flags.can_disable_srgb_decoder =
 315                 epoxy_has_gl_extension("GL_EXT_texture_sRGB_decode") &&
 316                 epoxy_has_gl_extension("GL_ARB_sampler_objects");
 317
 318         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 319         // will be halved when sampling them, and we need to compensate here.
 320         movit_texel_subpixel_precision /= 2.0;
 321
 322         resource_pool.reset(new ResourcePool);
 323         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 324                 output_channel[i].parent = this;
 325                 output_channel[i].channel = i;
 326         }
 327
 328         ImageFormat inout_format;
 329         inout_format.color_space = COLORSPACE_sRGB;
 330         inout_format.gamma_curve = GAMMA_sRGB;
 331
 332         // Matches the 4:2:0 format created by the main chain.
 333         YCbCrFormat ycbcr_format;
 334         ycbcr_format.chroma_subsampling_x = 2;
 335         ycbcr_format.chroma_subsampling_y = 2;
 336         if (global_flags.ycbcr_rec709_coefficients) {
 337                 ycbcr_format.luma_coefficients = YCBCR_REC_709;
 338         } else {
 339                 ycbcr_format.luma_coefficients = YCBCR_REC_601;
 340         }
 341         ycbcr_format.full_range = false;
 342         ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
 343         ycbcr_format.cb_x_position = 0.0f;
 344         ycbcr_format.cr_x_position = 0.0f;
 345         ycbcr_format.cb_y_position = 0.5f;
 346         ycbcr_format.cr_y_position = 0.5f;
 347
 348         // Display chain; shows the live output produced by the main chain (or rather, a copy of it).
 349         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
 350         check_error();
 351         GLenum type = global_flags.x264_bit_depth > 8 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_BYTE;
 352         display_input = new YCbCrInput(inout_format, ycbcr_format, global_flags.width, global_flags.height, YCBCR_INPUT_SPLIT_Y_AND_CBCR, type);
 353         display_chain->add_input(display_input);
 354         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 355         display_chain->set_dither_bits(0);  // Don't bother.
 356         display_chain->finalize();
 357
 358         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));
 359
 360         // Must be instantiated after VideoEncoder has initialized global_flags.use_zerocopy.
 361         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
 362
 363         // Must be instantiated after the theme, as the theme decides the number of FFmpeg inputs.
 364         std::vector<FFmpegCapture *> video_inputs = theme->get_video_inputs();
 365         audio_mixer.reset(new AudioMixer(num_cards, video_inputs.size()));
 366
 367         httpd.add_endpoint("/channels", bind(&Mixer::get_channels_json, this), HTTPD::ALLOW_ALL_ORIGINS);
 368         for (int channel_idx = 2; channel_idx < theme->get_num_channels(); ++channel_idx) {
 369                 char url[256];
 370                 snprintf(url, sizeof(url), "/channels/%d/color", channel_idx);
 371                 httpd.add_endpoint(url, bind(&Mixer::get_channel_color_http, this, unsigned(channel_idx)), HTTPD::ALLOW_ALL_ORIGINS);
 372         }
 373
 374         // Start listening for clients only once VideoEncoder has written its header, if any.
 375         httpd.start(global_flags.http_port);
 376
 377         // First try initializing the then PCI devices, then USB, then
 378         // fill up with fake cards until we have the desired number of cards.
 379         unsigned num_pci_devices = 0;
 380         unsigned card_index = 0;
 381
 382         {
 383                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 384                 if (decklink_iterator != nullptr) {
 385                         for ( ; card_index < num_cards; ++card_index) {
 386                                 IDeckLink *decklink;
 387                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 388                                         break;
 389                                 }
 390
 391                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
 392                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
 393                                 if (!output->set_device(decklink)) {
 394                                         delete output;
 395                                         output = nullptr;
 396                                 }
 397                                 configure_card(card_index, capture, CardType::LIVE_CARD, output);
 398                                 ++num_pci_devices;
 399                         }
 400                         decklink_iterator->Release();
 401                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 402                 } else {
 403                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 404                 }
 405         }
 406
 407         unsigned num_usb_devices = BMUSBCapture::num_cards();
 408         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
 409                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 410                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 411                 configure_card(card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
 412         }
 413         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 414
 415         unsigned num_fake_cards = 0;
 416         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
 417                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 418                 configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
 419         }
 420
 421         if (num_fake_cards > 0) {
 422                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 423         }
 424
 425         // Initialize all video inputs the theme asked for. Note that these are
 426         // all put _after_ the regular cards, which stop at <num_cards> - 1.
 427         for (unsigned video_card_index = 0; video_card_index < video_inputs.size(); ++card_index, ++video_card_index) {
 428                 if (card_index >= MAX_VIDEO_CARDS) {
 429                         fprintf(stderr, "ERROR: Not enough card slots available for the videos the theme requested.\n");
 430                         exit(1);
 431                 }
 432                 configure_card(card_index, video_inputs[video_card_index], CardType::FFMPEG_INPUT, /*output=*/nullptr);
 433                 video_inputs[video_card_index]->set_card_index(card_index);
 434         }
 435         num_video_inputs = video_inputs.size();
 436
 437 #ifdef HAVE_CEF
 438         // Same, for HTML inputs.
 439         std::vector<CEFCapture *> html_inputs = theme->get_html_inputs();
 440         for (unsigned html_card_index = 0; html_card_index < html_inputs.size(); ++card_index, ++html_card_index) {
 441                 if (card_index >= MAX_VIDEO_CARDS) {
 442                         fprintf(stderr, "ERROR: Not enough card slots available for the HTML inputs the theme requested.\n");
 443                         exit(1);
 444                 }
 445                 configure_card(card_index, html_inputs[html_card_index], CardType::CEF_INPUT, /*output=*/nullptr);
 446                 html_inputs[html_card_index]->set_card_index(card_index);
 447         }
 448         num_html_inputs = html_inputs.size();
 449 #endif
 450
 451         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 452         BMUSBCapture::start_bm_thread();
 453
 454         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
 455                 cards[card_index].queue_length_policy.reset(card_index);
 456         }
 457
 458         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
 459
 460         if (global_flags.ten_bit_input) {
 461                 if (!v210Converter::has_hardware_support()) {
 462                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
 463                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 464                         exit(1);
 465                 }
 466                 v210_converter.reset(new v210Converter());
 467
 468                 // These are all the widths listed in the Blackmagic SDK documentation
 469                 // (section 2.7.3, “Display Modes”).
 470                 v210_converter->precompile_shader(720);
 471                 v210_converter->precompile_shader(1280);
 472                 v210_converter->precompile_shader(1920);
 473                 v210_converter->precompile_shader(2048);
 474                 v210_converter->precompile_shader(3840);
 475                 v210_converter->precompile_shader(4096);
 476         }
 477         if (global_flags.ten_bit_output) {
 478                 if (!v210Converter::has_hardware_support()) {
 479                         fprintf(stderr, "ERROR: --ten-bit-output requires support for OpenGL compute shaders\n");
 480                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 481                         exit(1);
 482                 }
 483         }
 484
 485         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
 486         display_timecode_in_stream = global_flags.display_timecode_in_stream;
 487         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
 488
 489         if (global_flags.enable_alsa_output) {
 490                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 491         }
 492         if (global_flags.output_card != -1) {
 493                 desired_output_card_index = global_flags.output_card;
 494                 set_output_card_internal(global_flags.output_card);
 495         }
 496
 497         output_jitter_history.register_metrics({{ "card", "output" }});
 498 }
 499
 500 Mixer::~Mixer()
 501 {
 502         httpd.stop();
 503         BMUSBCapture::stop_bm_thread();
 504
 505         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
 506                 cards[card_index].capture->stop_dequeue_thread();
 507                 if (cards[card_index].output) {
 508                         cards[card_index].output->end_output();
 509                         cards[card_index].output.reset();
 510                 }
 511         }
 512
 513         video_encoder.reset(nullptr);
 514 }
 515
 516 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, CardType card_type, DeckLinkOutput *output)
 517 {
 518         printf("Configuring card %d...\n", card_index);
 519
 520         CaptureCard *card = &cards[card_index];
 521         if (card->capture != nullptr) {
 522                 card->capture->stop_dequeue_thread();
 523         }
 524         card->capture.reset(capture);
 525         card->is_fake_capture = (card_type == CardType::FAKE_CAPTURE);
 526         card->is_cef_capture = (card_type == CardType::CEF_INPUT);
 527         card->may_have_dropped_last_frame = false;
 528         card->type = card_type;
 529         if (card->output.get() != output) {
 530                 card->output.reset(output);
 531         }
 532
 533         PixelFormat pixel_format;
 534         if (card_type == CardType::FFMPEG_INPUT) {
 535                 pixel_format = capture->get_current_pixel_format();
 536         } else if (card_type == CardType::CEF_INPUT) {
 537                 pixel_format = PixelFormat_8BitBGRA;
 538         } else if (global_flags.ten_bit_input) {
 539                 pixel_format = PixelFormat_10BitYCbCr;
 540         } else {
 541                 pixel_format = PixelFormat_8BitYCbCr;
 542         }
 543
 544         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 545         if (card->frame_allocator == nullptr) {
 546                 card->frame_allocator.reset(new PBOFrameAllocator(pixel_format, 8 << 20, global_flags.width, global_flags.height));  // 8 MB.
 547         }
 548         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 549         if (card->surface == nullptr) {
 550                 card->surface = create_surface_with_same_format(mixer_surface);
 551         }
 552         while (!card->new_frames.empty()) card->new_frames.pop_front();
 553         card->last_timecode = -1;
 554         card->capture->set_pixel_format(pixel_format);
 555         card->capture->configure_card();
 556
 557         // NOTE: start_bm_capture() happens in thread_func().
 558
 559         DeviceSpec device;
 560         if (card_type == CardType::FFMPEG_INPUT) {
 561                 device = DeviceSpec{InputSourceType::FFMPEG_VIDEO_INPUT, card_index - num_cards};
 562         } else {
 563                 device = DeviceSpec{InputSourceType::CAPTURE_CARD, card_index};
 564         }
 565         audio_mixer->reset_resampler(device);
 566         audio_mixer->set_display_name(device, card->capture->get_description());
 567         audio_mixer->trigger_state_changed_callback();
 568
 569         // Unregister old metrics, if any.
 570         if (!card->labels.empty()) {
 571                 const vector<pair<string, string>> &labels = card->labels;
 572                 card->jitter_history.unregister_metrics(labels);
 573                 card->queue_length_policy.unregister_metrics(labels);
 574                 global_metrics.remove("input_received_frames", labels);
 575                 global_metrics.remove("input_dropped_frames_jitter", labels);
 576                 global_metrics.remove("input_dropped_frames_error", labels);
 577                 global_metrics.remove("input_dropped_frames_resets", labels);
 578                 global_metrics.remove("input_queue_length_frames", labels);
 579                 global_metrics.remove("input_queue_duped_frames", labels);
 580
 581                 global_metrics.remove("input_has_signal_bool", labels);
 582                 global_metrics.remove("input_is_connected_bool", labels);
 583                 global_metrics.remove("input_interlaced_bool", labels);
 584                 global_metrics.remove("input_width_pixels", labels);
 585                 global_metrics.remove("input_height_pixels", labels);
 586                 global_metrics.remove("input_frame_rate_nom", labels);
 587                 global_metrics.remove("input_frame_rate_den", labels);
 588                 global_metrics.remove("input_sample_rate_hz", labels);
 589         }
 590
 591         // Register metrics.
 592         vector<pair<string, string>> labels;
 593         char card_name[64];
 594         snprintf(card_name, sizeof(card_name), "%d", card_index);
 595         labels.emplace_back("card", card_name);
 596
 597         switch (card_type) {
 598         case CardType::LIVE_CARD:
 599                 labels.emplace_back("cardtype", "live");
 600                 break;
 601         case CardType::FAKE_CAPTURE:
 602                 labels.emplace_back("cardtype", "fake");
 603                 break;
 604         case CardType::FFMPEG_INPUT:
 605                 labels.emplace_back("cardtype", "ffmpeg");
 606                 break;
 607         case CardType::CEF_INPUT:
 608                 labels.emplace_back("cardtype", "cef");
 609                 break;
 610         default:
 611                 assert(false);
 612         }
 613         card->jitter_history.register_metrics(labels);
 614         card->queue_length_policy.register_metrics(labels);
 615         global_metrics.add("input_received_frames", labels, &card->metric_input_received_frames);
 616         global_metrics.add("input_dropped_frames_jitter", labels, &card->metric_input_dropped_frames_jitter);
 617         global_metrics.add("input_dropped_frames_error", labels, &card->metric_input_dropped_frames_error);
 618         global_metrics.add("input_dropped_frames_resets", labels, &card->metric_input_resets);
 619         global_metrics.add("input_queue_length_frames", labels, &card->metric_input_queue_length_frames, Metrics::TYPE_GAUGE);
 620         global_metrics.add("input_queue_duped_frames", labels, &card->metric_input_duped_frames);
 621
 622         global_metrics.add("input_has_signal_bool", labels, &card->metric_input_has_signal_bool, Metrics::TYPE_GAUGE);
 623         global_metrics.add("input_is_connected_bool", labels, &card->metric_input_is_connected_bool, Metrics::TYPE_GAUGE);
 624         global_metrics.add("input_interlaced_bool", labels, &card->metric_input_interlaced_bool, Metrics::TYPE_GAUGE);
 625         global_metrics.add("input_width_pixels", labels, &card->metric_input_width_pixels, Metrics::TYPE_GAUGE);
 626         global_metrics.add("input_height_pixels", labels, &card->metric_input_height_pixels, Metrics::TYPE_GAUGE);
 627         global_metrics.add("input_frame_rate_nom", labels, &card->metric_input_frame_rate_nom, Metrics::TYPE_GAUGE);
 628         global_metrics.add("input_frame_rate_den", labels, &card->metric_input_frame_rate_den, Metrics::TYPE_GAUGE);
 629         global_metrics.add("input_sample_rate_hz", labels, &card->metric_input_sample_rate_hz, Metrics::TYPE_GAUGE);
 630         card->labels = labels;
 631 }
 632
 633 void Mixer::set_output_card_internal(int card_index)
 634 {
 635         // We don't really need to take card_mutex, since we're in the mixer
 636         // thread and don't mess with any queues (which is the only thing that happens
 637         // from other threads), but it's probably the safest in the long run.
 638         unique_lock<mutex> lock(card_mutex);
 639         if (output_card_index != -1) {
 640                 // Switch the old card from output to input.
 641                 CaptureCard *old_card = &cards[output_card_index];
 642                 old_card->output->end_output();
 643
 644                 // Stop the fake card that we put into place.
 645                 // This needs to _not_ happen under the mutex, to avoid deadlock
 646                 // (delivering the last frame needs to take the mutex).
 647                 CaptureInterface *fake_capture = old_card->capture.get();
 648                 lock.unlock();
 649                 fake_capture->stop_dequeue_thread();
 650                 lock.lock();
 651                 old_card->capture = move(old_card->parked_capture);  // TODO: reset the metrics
 652                 old_card->is_fake_capture = false;
 653                 old_card->capture->start_bm_capture();
 654         }
 655         if (card_index != -1) {
 656                 CaptureCard *card = &cards[card_index];
 657                 CaptureInterface *capture = card->capture.get();
 658                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
 659                 // several seconds to complete (blocking on DisableVideoInput);
 660                 // see if we can maybe do it asynchronously.
 661                 lock.unlock();
 662                 capture->stop_dequeue_thread();
 663                 lock.lock();
 664                 card->parked_capture = move(card->capture);
 665                 CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 666                 configure_card(card_index, fake_capture, CardType::FAKE_CAPTURE, card->output.release());
 667                 card->queue_length_policy.reset(card_index);
 668                 card->capture->start_bm_capture();
 669                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
 670                 card->output->start_output(desired_output_video_mode, pts_int);
 671         }
 672         output_card_index = card_index;
 673         output_jitter_history.clear();
 674 }
 675
 676 namespace {
 677
 678 int unwrap_timecode(uint16_t current_wrapped, int last)
 679 {
 680         uint16_t last_wrapped = last & 0xffff;
 681         if (current_wrapped > last_wrapped) {
 682                 return (last & ~0xffff) | current_wrapped;
 683         } else {
 684                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 685         }
 686 }
 687
 688 DeviceSpec card_index_to_device(unsigned card_index, unsigned num_cards)
 689 {
 690         if (card_index >= num_cards) {
 691                 return DeviceSpec{InputSourceType::FFMPEG_VIDEO_INPUT, card_index - num_cards};
 692         } else {
 693                 return DeviceSpec{InputSourceType::CAPTURE_CARD, card_index};
 694         }
 695 }
 696
 697 }  // namespace
 698
 699 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 700                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 701                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 702 {
 703         DeviceSpec device = card_index_to_device(card_index, num_cards);
 704         CaptureCard *card = &cards[card_index];
 705
 706         ++card->metric_input_received_frames;
 707         card->metric_input_has_signal_bool = video_format.has_signal;
 708         card->metric_input_is_connected_bool = video_format.is_connected;
 709         card->metric_input_interlaced_bool = video_format.interlaced;
 710         card->metric_input_width_pixels = video_format.width;
 711         card->metric_input_height_pixels = video_format.height;
 712         card->metric_input_frame_rate_nom = video_format.frame_rate_nom;
 713         card->metric_input_frame_rate_den = video_format.frame_rate_den;
 714         card->metric_input_sample_rate_hz = audio_format.sample_rate;
 715
 716         if (is_mode_scanning[card_index]) {
 717                 if (video_format.has_signal) {
 718                         // Found a stable signal, so stop scanning.
 719                         is_mode_scanning[card_index] = false;
 720                 } else {
 721                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
 722                         steady_clock::time_point now = steady_clock::now();
 723                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 724                         if (sec_since_last_switch > switch_time_s) {
 725                                 // It isn't this mode; try the next one.
 726                                 mode_scanlist_index[card_index]++;
 727                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 728                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 729                                 last_mode_scan_change[card_index] = now;
 730                         }
 731                 }
 732         }
 733
 734         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;
 735         if (num_samples > OUTPUT_FREQUENCY / 10 && card->type != CardType::FFMPEG_INPUT) {
 736                 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",
 737                         spec_to_string(device).c_str(), int(audio_frame.len), int(audio_offset),
 738                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 739                 if (video_frame.owner) {
 740                         video_frame.owner->release_frame(video_frame);
 741                 }
 742                 if (audio_frame.owner) {
 743                         audio_frame.owner->release_frame(audio_frame);
 744                 }
 745                 return;
 746         }
 747
 748         int64_t frame_length;
 749         bool audio_only_frame = false;
 750         if (video_frame.len - video_offset == 0 && num_samples > 0) {
 751                 // Audio-only frame (probably from FFmpegCapture).
 752                 frame_length = int64_t(TIMEBASE) * num_samples / OUTPUT_FREQUENCY;
 753                 audio_only_frame = true;
 754         } else {
 755                 frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 756         }
 757         assert(frame_length > 0);
 758
 759         int dropped_frames = 0;
 760         if (card->last_timecode != -1) {
 761                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 762         }
 763
 764         // Number of samples per frame if we need to insert silence.
 765         // (Could be nonintegral, but resampling will save us then.)
 766         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 767
 768         if (dropped_frames > MAX_FPS * 2) {
 769                 fprintf(stderr, "%s lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 770                         spec_to_string(device).c_str(), card->last_timecode, timecode);
 771                 audio_mixer->reset_resampler(device);
 772                 dropped_frames = 0;
 773                 ++card->metric_input_resets;
 774         } else if (dropped_frames > 0) {
 775                 // Insert silence as needed.
 776                 fprintf(stderr, "%s dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 777                         spec_to_string(device).c_str(), dropped_frames, timecode);
 778                 card->metric_input_dropped_frames_error += dropped_frames;
 779
 780                 bool success;
 781                 do {
 782                         success = audio_mixer->add_silence(device, silence_samples, dropped_frames, frame_length);
 783                 } while (!success);
 784         }
 785
 786         if (num_samples > 0) {
 787                 audio_mixer->add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
 788         }
 789
 790         // Done with the audio, so release it.
 791         if (audio_frame.owner) {
 792                 audio_frame.owner->release_frame(audio_frame);
 793         }
 794
 795         card->last_timecode = timecode;
 796
 797         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 798
 799         size_t cbcr_width, cbcr_height, cbcr_offset, y_offset;
 800         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
 801         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
 802                 // The calculation above is wrong for planar Y'CbCr, so just override it.
 803                 assert(card->type == CardType::FFMPEG_INPUT);
 804                 assert(video_offset == 0);
 805                 expected_length = video_frame.len;
 806
 807                 userdata->ycbcr_format = (static_cast<FFmpegCapture *>(card->capture.get()))->get_current_frame_ycbcr_format();
 808                 cbcr_width = video_format.width / userdata->ycbcr_format.chroma_subsampling_x;
 809                 cbcr_height = video_format.height / userdata->ycbcr_format.chroma_subsampling_y;
 810                 cbcr_offset = video_format.width * video_format.height;
 811                 y_offset = 0;
 812         } else {
 813                 // All the other Y'CbCr formats are 4:2:2.
 814                 cbcr_width = video_format.width / 2;
 815                 cbcr_height = video_format.height;
 816                 cbcr_offset = video_offset / 2;
 817                 y_offset = video_frame.size / 2 + video_offset / 2;
 818         }
 819         if (video_frame.len - video_offset == 0 ||
 820             video_frame.len - video_offset != expected_length) {
 821                 if (video_frame.len != 0) {
 822                         printf("%s: Dropping video frame with wrong length (%ld; expected %ld)\n",
 823                                 spec_to_string(device).c_str(), video_frame.len - video_offset, expected_length);
 824                 }
 825                 if (video_frame.owner) {
 826                         video_frame.owner->release_frame(video_frame);
 827                 }
 828
 829                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 830                 // so that pts can go up accordingly. (This is also used for audio-only frames.)
 831                 {
 832                         unique_lock<mutex> lock(card_mutex);
 833                         CaptureCard::NewFrame new_frame;
 834                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 835                         new_frame.length = frame_length;
 836                         new_frame.interlaced = false;
 837                         new_frame.dropped_frames = dropped_frames;
 838                         new_frame.audio_only = audio_only_frame;
 839                         new_frame.received_timestamp = video_frame.received_timestamp;
 840                         card->new_frames.push_back(move(new_frame));
 841                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
 842                 }
 843                 card->new_frames_changed.notify_all();
 844                 return;
 845         }
 846
 847         unsigned num_fields = video_format.interlaced ? 2 : 1;
 848         steady_clock::time_point frame_upload_start;
 849         bool interlaced_stride = false;
 850         if (video_format.interlaced) {
 851                 // Send the two fields along as separate frames; the other side will need to add
 852                 // a deinterlacer to actually get this right.
 853                 assert(video_format.height % 2 == 0);
 854                 video_format.height /= 2;
 855                 cbcr_height /= 2;
 856                 assert(frame_length % 2 == 0);
 857                 frame_length /= 2;
 858                 num_fields = 2;
 859                 if (video_format.second_field_start == 1) {
 860                         interlaced_stride = true;
 861                 }
 862                 frame_upload_start = steady_clock::now();
 863         }
 864         userdata->last_interlaced = video_format.interlaced;
 865         userdata->last_has_signal = video_format.has_signal;
 866         userdata->last_is_connected = video_format.is_connected;
 867         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 868         userdata->last_frame_rate_den = video_format.frame_rate_den;
 869         RefCountedFrame frame(video_frame);
 870
 871         // Upload the textures.
 872         for (unsigned field = 0; field < num_fields; ++field) {
 873                 // Put the actual texture upload in a lambda that is executed in the main thread.
 874                 // It is entirely possible to do this in the same thread (and it might even be
 875                 // faster, depending on the GPU and driver), but it appears to be trickling
 876                 // driver bugs very easily.
 877                 //
 878                 // Note that this means we must hold on to the actual frame data in <userdata>
 879                 // until the upload command is run, but we hold on to <frame> much longer than that
 880                 // (in fact, all the way until we no longer use the texture in rendering).
 881                 auto upload_func = [this, field, video_format, y_offset, video_offset, cbcr_offset, cbcr_width, cbcr_height, interlaced_stride, userdata]() {
 882                         unsigned field_start_line;
 883                         if (field == 1) {
 884                                 field_start_line = video_format.second_field_start;
 885                         } else {
 886                                 field_start_line = video_format.extra_lines_top;
 887                         }
 888
 889                         // For anything not FRAME_FORMAT_YCBCR_10BIT, v210_width will be nonsensical but not used.
 890                         size_t v210_width = video_format.stride / sizeof(uint32_t);
 891                         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, cbcr_width, cbcr_height, v210_width);
 892
 893                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
 894                         check_error();
 895
 896                         switch (userdata->pixel_format) {
 897                         case PixelFormat_10BitYCbCr: {
 898                                 size_t field_start = video_offset + video_format.stride * field_start_line;
 899                                 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);
 900                                 v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
 901                                 break;
 902                         }
 903                         case PixelFormat_8BitYCbCr: {
 904                                 size_t field_y_start = y_offset + video_format.width * field_start_line;
 905                                 size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 906
 907                                 // Make up our own strides, since we are interleaving.
 908                                 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);
 909                                 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);
 910                                 break;
 911                         }
 912                         case PixelFormat_8BitYCbCrPlanar: {
 913                                 assert(field_start_line == 0);  // We don't really support interlaced here.
 914                                 size_t field_y_start = y_offset;
 915                                 size_t field_cb_start = cbcr_offset;
 916                                 size_t field_cr_start = cbcr_offset + cbcr_width * cbcr_height;
 917
 918                                 // Make up our own strides, since we are interleaving.
 919                                 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);
 920                                 upload_texture(userdata->tex_cb[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cb_start);
 921                                 upload_texture(userdata->tex_cr[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cr_start);
 922                                 break;
 923                         }
 924                         case PixelFormat_8BitBGRA: {
 925                                 size_t field_start = video_offset + video_format.stride * field_start_line;
 926                                 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);
 927                                 // These could be asked to deliver mipmaps at any time.
 928                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
 929                                 check_error();
 930                                 glGenerateMipmap(GL_TEXTURE_2D);
 931                                 check_error();
 932                                 glBindTexture(GL_TEXTURE_2D, 0);
 933                                 check_error();
 934                                 break;
 935                         }
 936                         default:
 937                                 assert(false);
 938                         }
 939
 940                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 941                         check_error();
 942                 };
 943
 944                 if (field == 1) {
 945                         // Don't upload the second field as fast as we can; wait until
 946                         // the field time has approximately passed. (Otherwise, we could
 947                         // get timing jitter against the other sources, and possibly also
 948                         // against the video display, although the latter is not as critical.)
 949                         // This requires our system clock to be reasonably close to the
 950                         // video clock, but that's not an unreasonable assumption.
 951                         steady_clock::time_point second_field_start = frame_upload_start +
 952                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
 953                         this_thread::sleep_until(second_field_start);
 954                 }
 955
 956                 {
 957                         unique_lock<mutex> lock(card_mutex);
 958                         CaptureCard::NewFrame new_frame;
 959                         new_frame.frame = frame;
 960                         new_frame.length = frame_length;
 961                         new_frame.field = field;
 962                         new_frame.interlaced = video_format.interlaced;
 963                         new_frame.upload_func = upload_func;
 964                         new_frame.dropped_frames = dropped_frames;
 965                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
 966                         card->new_frames.push_back(move(new_frame));
 967                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
 968                         card->may_have_dropped_last_frame = false;
 969                 }
 970                 card->new_frames_changed.notify_all();
 971         }
 972 }
 973
 974 void Mixer::bm_hotplug_add(libusb_device *dev)
 975 {
 976         lock_guard<mutex> lock(hotplug_mutex);
 977         hotplugged_cards.push_back(dev);
 978 }
 979
 980 void Mixer::bm_hotplug_remove(unsigned card_index)
 981 {
 982         cards[card_index].new_frames_changed.notify_all();
 983 }
 984
 985 void Mixer::thread_func()
 986 {
 987         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
 988
 989         eglBindAPI(EGL_OPENGL_API);
 990         QOpenGLContext *context = create_context(mixer_surface);
 991         if (!make_current(context, mixer_surface)) {
 992                 printf("oops\n");
 993                 exit(1);
 994         }
 995
 996         // Start the actual capture. (We don't want to do it before we're actually ready
 997         // to process output frames.)
 998         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
 999                 if (int(card_index) != output_card_index) {
1000                         cards[card_index].capture->start_bm_capture();
1001                 }
1002         }
1003
1004         BasicStats basic_stats(/*verbose=*/true, /*use_opengl=*/true);
1005         int stats_dropped_frames = 0;
1006
1007         while (!should_quit) {
1008                 if (desired_output_card_index != output_card_index) {
1009                         set_output_card_internal(desired_output_card_index);
1010                 }
1011                 if (output_card_index != -1 &&
1012                     desired_output_video_mode != output_video_mode) {
1013                         DeckLinkOutput *output = cards[output_card_index].output.get();
1014                         output->end_output();
1015                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
1016                         output->start_output(desired_output_video_mode, pts_int);
1017                 }
1018
1019                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
1020                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
1021
1022                 bool master_card_is_output;
1023                 unsigned master_card_index;
1024                 if (output_card_index != -1) {
1025                         master_card_is_output = true;
1026                         master_card_index = output_card_index;
1027                 } else {
1028                         master_card_is_output = false;
1029                         master_card_index = theme->map_signal(master_clock_channel);
1030                         assert(master_card_index < num_cards + num_video_inputs);
1031                 }
1032
1033                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
1034                 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);
1035                 stats_dropped_frames += output_frame_info.dropped_frames;
1036
1037                 handle_hotplugged_cards();
1038
1039                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1040                         DeviceSpec device = card_index_to_device(card_index, num_cards);
1041                         if (card_index == master_card_index || !has_new_frame[card_index]) {
1042                                 continue;
1043                         }
1044                         if (new_frames[card_index].frame->len == 0 &&
1045                             !new_frames[card_index].audio_only) {
1046                                 ++new_frames[card_index].dropped_frames;
1047                         }
1048                         if (new_frames[card_index].dropped_frames > 0) {
1049                                 printf("%s dropped %d frames before this\n",
1050                                         spec_to_string(device).c_str(), int(new_frames[card_index].dropped_frames));
1051                         }
1052                 }
1053
1054                 // If the first card is reporting a corrupted or otherwise dropped frame,
1055                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
1056                 if (!master_card_is_output && new_frames[master_card_index].frame->len == 0) {
1057                         ++stats_dropped_frames;
1058                         pts_int += new_frames[master_card_index].length;
1059                         continue;
1060                 }
1061
1062                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1063                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
1064                                 continue;
1065
1066                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
1067                         assert(new_frame->frame != nullptr);
1068                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
1069                         check_error();
1070
1071                         // The new texture might need uploading before use.
1072                         if (new_frame->upload_func) {
1073                                 new_frame->upload_func();
1074                                 new_frame->upload_func = nullptr;
1075                         }
1076                 }
1077
1078                 int64_t frame_duration = output_frame_info.frame_duration;
1079                 render_one_frame(frame_duration);
1080                 {
1081                         lock_guard<mutex> lock(frame_num_mutex);
1082                         ++frame_num;
1083                 }
1084                 frame_num_updated.notify_all();
1085                 pts_int += frame_duration;
1086
1087                 basic_stats.update(frame_num, stats_dropped_frames);
1088                 // if (frame_num % 100 == 0) chain->print_phase_timing();
1089
1090                 if (should_cut.exchange(false)) {  // Test and clear.
1091                         video_encoder->do_cut(frame_num);
1092                 }
1093
1094 #if 0
1095                 // Reset every 100 frames, so that local variations in frame times
1096                 // (especially for the first few frames, when the shaders are
1097                 // compiled etc.) don't make it hard to measure for the entire
1098                 // remaining duration of the program.
1099                 if (frame == 10000) {
1100                         frame = 0;
1101                         start = now;
1102                 }
1103 #endif
1104                 check_error();
1105         }
1106
1107         resource_pool->clean_context();
1108 }
1109
1110 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
1111 {
1112         if (output_card_index != -1) {
1113                 // The output card (ie., cards[output_card_index].output) is the master clock,
1114                 // so no input card (ie., cards[card_index].capture) is.
1115                 return false;
1116         }
1117         return (card_index == master_card_index);
1118 }
1119
1120 void Mixer::trim_queue(CaptureCard *card, size_t safe_queue_length)
1121 {
1122         // Count the number of frames in the queue, including any frames
1123         // we dropped. It's hard to know exactly how we should deal with
1124         // dropped (corrupted) input frames; they don't help our goal of
1125         // avoiding starvation, but they still add to the problem of latency.
1126         // Since dropped frames is going to mean a bump in the signal anyway,
1127         // we err on the side of having more stable latency instead.
1128         unsigned queue_length = 0;
1129         for (const CaptureCard::NewFrame &frame : card->new_frames) {
1130                 queue_length += frame.dropped_frames + 1;
1131         }
1132
1133         // If needed, drop frames until the queue is below the safe limit.
1134         // We prefer to drop from the head, because all else being equal,
1135         // we'd like more recent frames (less latency).
1136         unsigned dropped_frames = 0;
1137         while (queue_length > safe_queue_length) {
1138                 assert(!card->new_frames.empty());
1139                 assert(queue_length > card->new_frames.front().dropped_frames);
1140                 queue_length -= card->new_frames.front().dropped_frames;
1141
1142                 if (queue_length <= safe_queue_length) {
1143                         // No need to drop anything.
1144                         break;
1145                 }
1146
1147                 card->new_frames.pop_front();
1148                 card->new_frames_changed.notify_all();
1149                 --queue_length;
1150                 ++dropped_frames;
1151
1152                 if (queue_length == 0 && card->is_cef_capture) {
1153                         card->may_have_dropped_last_frame = true;
1154                 }
1155         }
1156
1157         card->metric_input_dropped_frames_jitter += dropped_frames;
1158         card->metric_input_queue_length_frames = queue_length;
1159
1160 #if 0
1161         if (dropped_frames > 0) {
1162                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
1163                         card_index, dropped_frames);
1164         }
1165 #endif
1166 }
1167
1168 pair<string, string> Mixer::get_channels_json()
1169 {
1170         Channels ret;
1171         for (int channel_idx = 2; channel_idx < theme->get_num_channels(); ++channel_idx) {
1172                 Channel *channel = ret.add_channel();
1173                 channel->set_index(channel_idx);
1174                 channel->set_name(theme->get_channel_name(channel_idx));
1175                 channel->set_color(theme->get_channel_color(channel_idx));
1176         }
1177         string contents;
1178         google::protobuf::util::MessageToJsonString(ret, &contents);  // Ignore any errors.
1179         return make_pair(contents, "text/json");
1180 }
1181
1182 pair<string, string> Mixer::get_channel_color_http(unsigned channel_idx)
1183 {
1184         return make_pair(theme->get_channel_color(channel_idx), "text/plain");
1185 }
1186
1187 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])
1188 {
1189         OutputFrameInfo output_frame_info;
1190 start:
1191         unique_lock<mutex> lock(card_mutex, defer_lock);
1192         if (master_card_is_output) {
1193                 // Clocked to the output, so wait for it to be ready for the next frame.
1194                 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);
1195                 lock.lock();
1196         } else {
1197                 // Wait for the master card to have a new frame.
1198                 // TODO: Add a timeout.
1199                 output_frame_info.is_preroll = false;
1200                 lock.lock();
1201                 cards[master_card_index].new_frames_changed.wait(lock, [this, master_card_index]{ return !cards[master_card_index].new_frames.empty() || cards[master_card_index].capture->get_disconnected(); });
1202         }
1203
1204         if (master_card_is_output) {
1205                 handle_hotplugged_cards();
1206         } else if (cards[master_card_index].new_frames.empty()) {
1207                 // We were woken up, but not due to a new frame. Deal with it
1208                 // and then restart.
1209                 assert(cards[master_card_index].capture->get_disconnected());
1210                 handle_hotplugged_cards();
1211                 lock.unlock();
1212                 goto start;
1213         }
1214
1215         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1216                 CaptureCard *card = &cards[card_index];
1217                 if (card->new_frames.empty()) {  // Starvation.
1218                         ++card->metric_input_duped_frames;
1219 #ifdef HAVE_CEF
1220                         if (card->is_cef_capture && card->may_have_dropped_last_frame) {
1221                                 // Unlike other sources, CEF is not guaranteed to send us a steady
1222                                 // stream of frames, so we'll have to ask it to repaint the frame
1223                                 // we dropped. (may_have_dropped_last_frame is set whenever we
1224                                 // trim the queue completely away, and cleared when we actually
1225                                 // get a new frame.)
1226                                 ((CEFCapture *)card->capture.get())->request_new_frame();
1227                         }
1228 #endif
1229                 } else {
1230                         new_frames[card_index] = move(card->new_frames.front());
1231                         has_new_frame[card_index] = true;
1232                         card->new_frames.pop_front();
1233                         card->new_frames_changed.notify_all();
1234                 }
1235         }
1236
1237         if (!master_card_is_output) {
1238                 output_frame_info.frame_timestamp = new_frames[master_card_index].received_timestamp;
1239                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
1240                 output_frame_info.frame_duration = new_frames[master_card_index].length;
1241         }
1242
1243         if (!output_frame_info.is_preroll) {
1244                 output_jitter_history.frame_arrived(output_frame_info.frame_timestamp, output_frame_info.frame_duration, output_frame_info.dropped_frames);
1245         }
1246
1247         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1248                 CaptureCard *card = &cards[card_index];
1249                 if (has_new_frame[card_index] &&
1250                     !input_card_is_master_clock(card_index, master_card_index) &&
1251                     !output_frame_info.is_preroll) {
1252                         card->queue_length_policy.update_policy(
1253                                 output_frame_info.frame_timestamp,
1254                                 card->jitter_history.get_expected_next_frame(),
1255                                 new_frames[master_card_index].length,
1256                                 output_frame_info.frame_duration,
1257                                 card->jitter_history.estimate_max_jitter(),
1258                                 output_jitter_history.estimate_max_jitter());
1259                         trim_queue(card, min<int>(global_flags.max_input_queue_frames,
1260                                                   card->queue_length_policy.get_safe_queue_length()));
1261                 }
1262         }
1263
1264         // This might get off by a fractional sample when changing master card
1265         // between ones with different frame rates, but that's fine.
1266         int num_samples_times_timebase = OUTPUT_FREQUENCY * output_frame_info.frame_duration + fractional_samples;
1267         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
1268         fractional_samples = num_samples_times_timebase % TIMEBASE;
1269         assert(output_frame_info.num_samples >= 0);
1270
1271         return output_frame_info;
1272 }
1273
1274 void Mixer::handle_hotplugged_cards()
1275 {
1276         // Check for cards that have been disconnected since last frame.
1277         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1278                 CaptureCard *card = &cards[card_index];
1279                 if (card->capture->get_disconnected()) {
1280                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
1281                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1282                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
1283                         card->queue_length_policy.reset(card_index);
1284                         card->capture->start_bm_capture();
1285                 }
1286         }
1287
1288         // Check for cards that have been connected since last frame.
1289         vector<libusb_device *> hotplugged_cards_copy;
1290         {
1291                 lock_guard<mutex> lock(hotplug_mutex);
1292                 swap(hotplugged_cards, hotplugged_cards_copy);
1293         }
1294         for (libusb_device *new_dev : hotplugged_cards_copy) {
1295                 // Look for a fake capture card where we can stick this in.
1296                 int free_card_index = -1;
1297                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1298                         if (cards[card_index].is_fake_capture) {
1299                                 free_card_index = card_index;
1300                                 break;
1301                         }
1302                 }
1303
1304                 if (free_card_index == -1) {
1305                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
1306                         libusb_unref_device(new_dev);
1307                 } else {
1308                         // BMUSBCapture takes ownership.
1309                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
1310                         CaptureCard *card = &cards[free_card_index];
1311                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
1312                         configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
1313                         card->queue_length_policy.reset(free_card_index);
1314                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1315                         capture->start_bm_capture();
1316                 }
1317         }
1318 }
1319
1320
1321 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)
1322 {
1323         // Resample the audio as needed, including from previously dropped frames.
1324         assert(num_cards > 0);
1325         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
1326                 const bool dropped_frame = (frame_num != dropped_frames);
1327                 {
1328                         // Signal to the audio thread to process this frame.
1329                         // Note that if the frame is a dropped frame, we signal that
1330                         // we don't want to use this frame as base for adjusting
1331                         // the resampler rate. The reason for this is that the timing
1332                         // of these frames is often way too late; they typically don't
1333                         // “arrive” before we synthesize them. Thus, we could end up
1334                         // in a situation where we have inserted e.g. five audio frames
1335                         // into the queue before we then start pulling five of them
1336                         // back out. This makes ResamplingQueue overestimate the delay,
1337                         // causing undue resampler changes. (We _do_ use the last,
1338                         // non-dropped frame; perhaps we should just discard that as well,
1339                         // since dropped frames are expected to be rare, and it might be
1340                         // better to just wait until we have a slightly more normal situation).
1341                         unique_lock<mutex> lock(audio_mutex);
1342                         bool adjust_rate = !dropped_frame && !is_preroll;
1343                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
1344                         audio_task_queue_changed.notify_one();
1345                 }
1346                 if (dropped_frame) {
1347                         // For dropped frames, increase the pts. Note that if the format changed
1348                         // in the meantime, we have no way of detecting that; we just have to
1349                         // assume the frame length is always the same.
1350                         pts_int += length_per_frame;
1351                 }
1352         }
1353 }
1354
1355 void Mixer::render_one_frame(int64_t duration)
1356 {
1357         // Determine the time code for this frame before we start rendering.
1358         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1359         if (display_timecode_on_stdout) {
1360                 printf("Timecode: '%s'\n", timecode_text.c_str());
1361         }
1362
1363         // Update Y'CbCr settings for all cards.
1364         {
1365                 unique_lock<mutex> lock(card_mutex);
1366                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1367                         YCbCrInterpretation *interpretation = &ycbcr_interpretation[card_index];
1368                         input_state.ycbcr_coefficients_auto[card_index] = interpretation->ycbcr_coefficients_auto;
1369                         input_state.ycbcr_coefficients[card_index] = interpretation->ycbcr_coefficients;
1370                         input_state.full_range[card_index] = interpretation->full_range;
1371                 }
1372         }
1373
1374         // Get the main chain from the theme, and set its state immediately.
1375         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1376         EffectChain *chain = theme_main_chain.chain;
1377         theme_main_chain.setup_chain();
1378         //theme_main_chain.chain->enable_phase_timing(true);
1379
1380         // If HDMI/SDI output is active and the user has requested auto mode,
1381         // its mode overrides the existing Y'CbCr setting for the chain.
1382         YCbCrLumaCoefficients ycbcr_output_coefficients;
1383         if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
1384                 ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
1385         } else {
1386                 ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
1387         }
1388
1389         // TODO: Reduce the duplication against theme.cpp.
1390         YCbCrFormat output_ycbcr_format;
1391         output_ycbcr_format.chroma_subsampling_x = 1;
1392         output_ycbcr_format.chroma_subsampling_y = 1;
1393         output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
1394         output_ycbcr_format.full_range = false;
1395         output_ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
1396         chain->change_ycbcr_output_format(output_ycbcr_format);
1397
1398         // Render main chain. If we're using zerocopy Quick Sync encoding
1399         // (the default case), we take an extra copy of the created outputs,
1400         // so that we can display it back to the screen later (it's less memory
1401         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1402         // Ideally, we'd like to avoid taking copies and just use the main textures
1403         // for display as well, but they're just views into VA-API memory and must be
1404         // unmapped during encoding, so we can't use them for display, unfortunately.
1405         GLuint y_tex, cbcr_full_tex, cbcr_tex;
1406         GLuint y_copy_tex, cbcr_copy_tex = 0;
1407         GLuint y_display_tex, cbcr_display_tex;
1408         GLenum y_type = (global_flags.x264_bit_depth > 8) ? GL_R16 : GL_R8;
1409         GLenum cbcr_type = (global_flags.x264_bit_depth > 8) ? GL_RG16 : GL_RG8;
1410         const bool is_zerocopy = video_encoder->is_zerocopy();
1411         if (is_zerocopy) {
1412                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1413                 y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1414                 cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1415
1416                 y_display_tex = y_copy_tex;
1417                 cbcr_display_tex = cbcr_copy_tex;
1418
1419                 // y_tex and cbcr_tex will be given by VideoEncoder.
1420         } else {
1421                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1422                 y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1423                 cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1424
1425                 y_display_tex = y_tex;
1426                 cbcr_display_tex = cbcr_tex;
1427         }
1428
1429         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1430         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1431         assert(got_frame);
1432
1433         GLuint fbo;
1434         if (is_zerocopy) {
1435                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1436         } else {
1437                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
1438         }
1439         check_error();
1440         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1441
1442         if (display_timecode_in_stream) {
1443                 // Render the timecode on top.
1444                 timecode_renderer->render_timecode(fbo, timecode_text);
1445         }
1446
1447         resource_pool->release_fbo(fbo);
1448
1449         if (is_zerocopy) {
1450                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1451         } else {
1452                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1453         }
1454         if (output_card_index != -1) {
1455                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
1456         }
1457         resource_pool->release_2d_texture(cbcr_full_tex);
1458
1459         // Set the right state for the Y' and CbCr textures we use for display.
1460         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1461         glBindTexture(GL_TEXTURE_2D, y_display_tex);
1462         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1463         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1464         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1465
1466         glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
1467         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1468         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1469         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1470
1471         RefCountedGLsync fence = video_encoder->end_frame();
1472
1473         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1474         // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
1475         DisplayFrame live_frame;
1476         live_frame.chain = display_chain.get();
1477         live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
1478                 display_input->set_texture_num(0, y_display_tex);
1479                 display_input->set_texture_num(1, cbcr_display_tex);
1480         };
1481         live_frame.ready_fence = fence;
1482         live_frame.input_frames = {};
1483         live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
1484         output_channel[OUTPUT_LIVE].output_frame(move(live_frame));
1485
1486         // Set up preview and any additional channels.
1487         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1488                 DisplayFrame display_frame;
1489                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1490                 display_frame.chain = move(chain.chain);
1491                 display_frame.setup_chain = move(chain.setup_chain);
1492                 display_frame.ready_fence = fence;
1493                 display_frame.input_frames = move(chain.input_frames);
1494                 display_frame.temp_textures = {};
1495                 output_channel[i].output_frame(move(display_frame));
1496         }
1497 }
1498
1499 void Mixer::audio_thread_func()
1500 {
1501         pthread_setname_np(pthread_self(), "Mixer_Audio");
1502
1503         while (!should_quit) {
1504                 AudioTask task;
1505
1506                 {
1507                         unique_lock<mutex> lock(audio_mutex);
1508                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1509                         if (should_quit) {
1510                                 return;
1511                         }
1512                         task = audio_task_queue.front();
1513                         audio_task_queue.pop();
1514                 }
1515
1516                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1517                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1518                 vector<float> samples_out = audio_mixer->get_output(
1519                         task.frame_timestamp,
1520                         task.num_samples,
1521                         rate_adjustment_policy);
1522
1523                 // Send the samples to the sound card, then add them to the output.
1524                 if (alsa) {
1525                         alsa->write(samples_out);
1526                 }
1527                 if (output_card_index != -1) {
1528                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1529                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1530                 }
1531                 video_encoder->add_audio(task.pts_int, move(samples_out));
1532         }
1533 }
1534
1535 void Mixer::release_display_frame(DisplayFrame *frame)
1536 {
1537         for (GLuint texnum : frame->temp_textures) {
1538                 resource_pool->release_2d_texture(texnum);
1539         }
1540         frame->temp_textures.clear();
1541         frame->ready_fence.reset();
1542         frame->input_frames.clear();
1543 }
1544
1545 void Mixer::start()
1546 {
1547         mixer_thread = thread(&Mixer::thread_func, this);
1548         audio_thread = thread(&Mixer::audio_thread_func, this);
1549 }
1550
1551 void Mixer::quit()
1552 {
1553         should_quit = true;
1554         audio_task_queue_changed.notify_one();
1555         mixer_thread.join();
1556         audio_thread.join();
1557 }
1558
1559 void Mixer::transition_clicked(int transition_num)
1560 {
1561         theme->transition_clicked(transition_num, pts());
1562 }
1563
1564 void Mixer::channel_clicked(int preview_num)
1565 {
1566         theme->channel_clicked(preview_num);
1567 }
1568
1569 YCbCrInterpretation Mixer::get_input_ycbcr_interpretation(unsigned card_index) const
1570 {
1571         unique_lock<mutex> lock(card_mutex);
1572         return ycbcr_interpretation[card_index];
1573 }
1574
1575 void Mixer::set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation)
1576 {
1577         unique_lock<mutex> lock(card_mutex);
1578         ycbcr_interpretation[card_index] = interpretation;
1579 }
1580
1581 void Mixer::start_mode_scanning(unsigned card_index)
1582 {
1583         assert(card_index < num_cards);
1584         if (is_mode_scanning[card_index]) {
1585                 return;
1586         }
1587         is_mode_scanning[card_index] = true;
1588         mode_scanlist[card_index].clear();
1589         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1590                 mode_scanlist[card_index].push_back(mode.first);
1591         }
1592         assert(!mode_scanlist[card_index].empty());
1593         mode_scanlist_index[card_index] = 0;
1594         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1595         last_mode_scan_change[card_index] = steady_clock::now();
1596 }
1597
1598 map<uint32_t, VideoMode> Mixer::get_available_output_video_modes() const
1599 {
1600         assert(desired_output_card_index != -1);
1601         unique_lock<mutex> lock(card_mutex);
1602         return cards[desired_output_card_index].output->get_available_video_modes();
1603 }
1604
1605 string Mixer::get_ffmpeg_filename(unsigned card_index) const
1606 {
1607         assert(card_index >= num_cards && card_index < num_cards + num_video_inputs);
1608         return ((FFmpegCapture *)(cards[card_index].capture.get()))->get_filename();
1609 }
1610
1611 void Mixer::set_ffmpeg_filename(unsigned card_index, const string &filename) {
1612         assert(card_index >= num_cards && card_index < num_cards + num_video_inputs);
1613         ((FFmpegCapture *)(cards[card_index].capture.get()))->change_filename(filename);
1614 }
1615
1616 void Mixer::wait_for_next_frame()
1617 {
1618         unique_lock<mutex> lock(frame_num_mutex);
1619         unsigned old_frame_num = frame_num;
1620         frame_num_updated.wait_for(lock, seconds(1),  // Timeout is just in case.
1621                 [old_frame_num, this]{ return this->frame_num > old_frame_num; });
1622 }
1623
1624 Mixer::OutputChannel::~OutputChannel()
1625 {
1626         if (has_current_frame) {
1627                 parent->release_display_frame(&current_frame);
1628         }
1629         if (has_ready_frame) {
1630                 parent->release_display_frame(&ready_frame);
1631         }
1632 }
1633
1634 void Mixer::OutputChannel::output_frame(DisplayFrame &&frame)
1635 {
1636         // Store this frame for display. Remove the ready frame if any
1637         // (it was seemingly never used).
1638         {
1639                 unique_lock<mutex> lock(frame_mutex);
1640                 if (has_ready_frame) {
1641                         parent->release_display_frame(&ready_frame);
1642                 }
1643                 ready_frame = move(frame);
1644                 has_ready_frame = true;
1645
1646                 // Call the callbacks under the mutex (they should be short),
1647                 // so that we don't race against a callback removal.
1648                 for (const auto &key_and_callback : new_frame_ready_callbacks) {
1649                         key_and_callback.second();
1650                 }
1651         }
1652
1653         // Reduce the number of callbacks by filtering duplicates. The reason
1654         // why we bother doing this is that Qt seemingly can get into a state
1655         // where its builds up an essentially unbounded queue of signals,
1656         // consuming more and more memory, and there's no good way of collapsing
1657         // user-defined signals or limiting the length of the queue.
1658         if (transition_names_updated_callback) {
1659                 vector<string> transition_names = global_mixer->get_transition_names();
1660                 bool changed = false;
1661                 if (transition_names.size() != last_transition_names.size()) {
1662                         changed = true;
1663                 } else {
1664                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1665                                 if (transition_names[i] != last_transition_names[i]) {
1666                                         changed = true;
1667                                         break;
1668                                 }
1669                         }
1670                 }
1671                 if (changed) {
1672                         transition_names_updated_callback(transition_names);
1673                         last_transition_names = transition_names;
1674                 }
1675         }
1676         if (name_updated_callback) {
1677                 string name = global_mixer->get_channel_name(channel);
1678                 if (name != last_name) {
1679                         name_updated_callback(name);
1680                         last_name = name;
1681                 }
1682         }
1683         if (color_updated_callback) {
1684                 string color = global_mixer->get_channel_color(channel);
1685                 if (color != last_color) {
1686                         color_updated_callback(color);
1687                         last_color = color;
1688                 }
1689         }
1690 }
1691
1692 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1693 {
1694         unique_lock<mutex> lock(frame_mutex);
1695         if (!has_current_frame && !has_ready_frame) {
1696                 return false;
1697         }
1698
1699         if (has_current_frame && has_ready_frame) {
1700                 // We have a new ready frame. Toss the current one.
1701                 parent->release_display_frame(&current_frame);
1702                 has_current_frame = false;
1703         }
1704         if (has_ready_frame) {
1705                 assert(!has_current_frame);
1706                 current_frame = move(ready_frame);
1707                 ready_frame.ready_fence.reset();  // Drop the refcount.
1708                 ready_frame.input_frames.clear();  // Drop the refcounts.
1709                 has_current_frame = true;
1710                 has_ready_frame = false;
1711         }
1712
1713         *frame = current_frame;
1714         return true;
1715 }
1716
1717 void Mixer::OutputChannel::add_frame_ready_callback(void *key, Mixer::new_frame_ready_callback_t callback)
1718 {
1719         unique_lock<mutex> lock(frame_mutex);
1720         new_frame_ready_callbacks[key] = callback;
1721 }
1722
1723 void Mixer::OutputChannel::remove_frame_ready_callback(void *key)
1724 {
1725         unique_lock<mutex> lock(frame_mutex);
1726         new_frame_ready_callbacks.erase(key);
1727 }
1728
1729 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1730 {
1731         transition_names_updated_callback = callback;
1732 }
1733
1734 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1735 {
1736         name_updated_callback = callback;
1737 }
1738
1739 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1740 {
1741         color_updated_callback = callback;
1742 }
1743
1744 mutex RefCountedGLsync::fence_lock;