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 <movit/util.h>
  14 #include <stdint.h>
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <sys/time.h>
  18 #include <time.h>
  19 #include <algorithm>
  20 #include <cmath>
  21 #include <condition_variable>
  22 #include <cstddef>
  23 #include <memory>
  24 #include <mutex>
  25 #include <string>
  26 #include <thread>
  27 #include <utility>
  28 #include <vector>
  29 #include <arpa/inet.h>
  30
  31 #include "bmusb/bmusb.h"
  32 #include "context.h"
  33 #include "decklink_capture.h"
  34 #include "defs.h"
  35 #include "flags.h"
  36 #include "video_encoder.h"
  37 #include "pbo_frame_allocator.h"
  38 #include "ref_counted_gl_sync.h"
  39 #include "timebase.h"
  40
  41 class QOpenGLContext;
  42
  43 using namespace movit;
  44 using namespace std;
  45 using namespace std::placeholders;
  46
  47 Mixer *global_mixer = nullptr;
  48
  49 namespace {
  50
  51 void convert_fixed24_to_fp32(float *dst, size_t out_channels, const uint8_t *src, size_t in_channels, size_t num_samples)
  52 {
  53         assert(in_channels >= out_channels);
  54         for (size_t i = 0; i < num_samples; ++i) {
  55                 for (size_t j = 0; j < out_channels; ++j) {
  56                         uint32_t s1 = *src++;
  57                         uint32_t s2 = *src++;
  58                         uint32_t s3 = *src++;
  59                         uint32_t s = s1 | (s1 << 8) | (s2 << 16) | (s3 << 24);
  60                         dst[i * out_channels + j] = int(s) * (1.0f / 4294967296.0f);
  61                 }
  62                 src += 3 * (in_channels - out_channels);
  63         }
  64 }
  65
  66 void convert_fixed32_to_fp32(float *dst, size_t out_channels, const uint8_t *src, size_t in_channels, size_t num_samples)
  67 {
  68         assert(in_channels >= out_channels);
  69         for (size_t i = 0; i < num_samples; ++i) {
  70                 for (size_t j = 0; j < out_channels; ++j) {
  71                         // Note: Assumes little-endian.
  72                         int32_t s = *(int32_t *)src;
  73                         dst[i * out_channels + j] = s * (1.0f / 4294967296.0f);
  74                         src += 4;
  75                 }
  76                 src += 4 * (in_channels - out_channels);
  77         }
  78 }
  79
  80 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  81 {
  82         if (interlaced) {
  83                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  84                         input_state->buffered_frames[card_index][frame_num] =
  85                                 input_state->buffered_frames[card_index][frame_num - 1];
  86                 }
  87                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  88         } else {
  89                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  90                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  91                 }
  92         }
  93 }
  94
  95 }  // namespace
  96
  97 void QueueLengthPolicy::update_policy(int queue_length)
  98 {
  99         if (queue_length < 0) {  // Starvation.
 100                 if (been_at_safe_point_since_last_starvation && safe_queue_length < 5) {
 101                         ++safe_queue_length;
 102                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frames\n",
 103                                 card_index, safe_queue_length);
 104                 }
 105                 frames_with_at_least_one = 0;
 106                 been_at_safe_point_since_last_starvation = false;
 107                 return;
 108         }
 109         if (queue_length > 0) {
 110                 if (queue_length >= int(safe_queue_length)) {
 111                         been_at_safe_point_since_last_starvation = true;
 112                 }
 113                 if (++frames_with_at_least_one >= 1000 && safe_queue_length > 0) {
 114                         --safe_queue_length;
 115                         fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frames\n",
 116                                 card_index, safe_queue_length);
 117                         frames_with_at_least_one = 0;
 118                 }
 119         } else {
 120                 frames_with_at_least_one = 0;
 121         }
 122 }
 123
 124 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 125         : httpd(),
 126           num_cards(num_cards),
 127           mixer_surface(create_surface(format)),
 128           h264_encoder_surface(create_surface(format)),
 129           correlation(OUTPUT_FREQUENCY),
 130           level_compressor(OUTPUT_FREQUENCY),
 131           limiter(OUTPUT_FREQUENCY),
 132           compressor(OUTPUT_FREQUENCY)
 133 {
 134         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 135         check_error();
 136
 137         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 138         // will be halved when sampling them, and we need to compensate here.
 139         movit_texel_subpixel_precision /= 2.0;
 140
 141         resource_pool.reset(new ResourcePool);
 142         theme.reset(new Theme(global_flags.theme_filename.c_str(), resource_pool.get(), num_cards));
 143         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 144                 output_channel[i].parent = this;
 145                 output_channel[i].channel = i;
 146         }
 147
 148         ImageFormat inout_format;
 149         inout_format.color_space = COLORSPACE_sRGB;
 150         inout_format.gamma_curve = GAMMA_sRGB;
 151
 152         // Display chain; shows the live output produced by the main chain (its RGBA version).
 153         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 154         check_error();
 155         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 156         display_chain->add_input(display_input);
 157         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 158         display_chain->set_dither_bits(0);  // Don't bother.
 159         display_chain->finalize();
 160
 161         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, WIDTH, HEIGHT, &httpd));
 162
 163         // Start listening for clients only once VideoEncoder has written its header, if any.
 164         httpd.start(9095);
 165
 166         // First try initializing the PCI devices, then USB, until we have the desired number of cards.
 167         unsigned num_pci_devices = 0, num_usb_devices = 0;
 168         unsigned card_index = 0;
 169
 170         IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 171         if (decklink_iterator != nullptr) {
 172                 for ( ; card_index < num_cards; ++card_index) {
 173                         IDeckLink *decklink;
 174                         if (decklink_iterator->Next(&decklink) != S_OK) {
 175                                 break;
 176                         }
 177
 178                         configure_card(card_index, format, new DeckLinkCapture(decklink, card_index));
 179                         ++num_pci_devices;
 180                 }
 181                 decklink_iterator->Release();
 182                 fprintf(stderr, "Found %d DeckLink PCI card(s).\n", num_pci_devices);
 183         } else {
 184                 fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 185         }
 186         for ( ; card_index < num_cards; ++card_index) {
 187                 configure_card(card_index, format, new BMUSBCapture(card_index - num_pci_devices));
 188                 ++num_usb_devices;
 189         }
 190
 191         if (num_usb_devices > 0) {
 192                 BMUSBCapture::start_bm_thread();
 193         }
 194
 195         for (card_index = 0; card_index < num_cards; ++card_index) {
 196                 cards[card_index].queue_length_policy.reset(card_index);
 197                 cards[card_index].capture->start_bm_capture();
 198         }
 199
 200         // Set up stuff for NV12 conversion.
 201
 202         // Cb/Cr shader.
 203         string cbcr_vert_shader =
 204                 "#version 130 \n"
 205                 " \n"
 206                 "in vec2 position; \n"
 207                 "in vec2 texcoord; \n"
 208                 "out vec2 tc0; \n"
 209                 "uniform vec2 foo_chroma_offset_0; \n"
 210                 " \n"
 211                 "void main() \n"
 212                 "{ \n"
 213                 "    // The result of glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0) is: \n"
 214                 "    // \n"
 215                 "    //   2.000  0.000  0.000 -1.000 \n"
 216                 "    //   0.000  2.000  0.000 -1.000 \n"
 217                 "    //   0.000  0.000 -2.000 -1.000 \n"
 218                 "    //   0.000  0.000  0.000  1.000 \n"
 219                 "    gl_Position = vec4(2.0 * position.x - 1.0, 2.0 * position.y - 1.0, -1.0, 1.0); \n"
 220                 "    vec2 flipped_tc = texcoord; \n"
 221                 "    tc0 = flipped_tc + foo_chroma_offset_0; \n"
 222                 "} \n";
 223         string cbcr_frag_shader =
 224                 "#version 130 \n"
 225                 "in vec2 tc0; \n"
 226                 "uniform sampler2D cbcr_tex; \n"
 227                 "out vec4 FragColor; \n"
 228                 "void main() { \n"
 229                 "    FragColor = texture(cbcr_tex, tc0); \n"
 230                 "} \n";
 231         vector<string> frag_shader_outputs;
 232         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
 233
 234         float vertices[] = {
 235                 0.0f, 2.0f,
 236                 0.0f, 0.0f,
 237                 2.0f, 0.0f
 238         };
 239         cbcr_vbo = generate_vbo(2, GL_FLOAT, sizeof(vertices), vertices);
 240         cbcr_position_attribute_index = glGetAttribLocation(cbcr_program_num, "position");
 241         cbcr_texcoord_attribute_index = glGetAttribLocation(cbcr_program_num, "texcoord");
 242
 243         r128.init(2, OUTPUT_FREQUENCY);
 244         r128.integr_start();
 245
 246         locut.init(FILTER_HPF, 2);
 247
 248         // If --flat-audio is given, turn off everything that messes with the sound,
 249         // except the final makeup gain.
 250         if (global_flags.flat_audio) {
 251                 set_locut_enabled(false);
 252                 set_limiter_enabled(false);
 253                 set_compressor_enabled(false);
 254         }
 255
 256         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
 257         // and there's a limit to how important the peak meter is.
 258         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16, /*frel=*/1.0);
 259
 260         if (global_flags.enable_alsa_output) {
 261                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 262         }
 263 }
 264
 265 Mixer::~Mixer()
 266 {
 267         resource_pool->release_glsl_program(cbcr_program_num);
 268         glDeleteBuffers(1, &cbcr_vbo);
 269         BMUSBCapture::stop_bm_thread();
 270
 271         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 272                 {
 273                         unique_lock<mutex> lock(bmusb_mutex);
 274                         cards[card_index].should_quit = true;  // Unblock thread.
 275                         cards[card_index].new_frames_changed.notify_all();
 276                 }
 277                 cards[card_index].capture->stop_dequeue_thread();
 278         }
 279
 280         video_encoder.reset(nullptr);
 281 }
 282
 283 void Mixer::configure_card(unsigned card_index, const QSurfaceFormat &format, CaptureInterface *capture)
 284 {
 285         printf("Configuring card %d...\n", card_index);
 286
 287         CaptureCard *card = &cards[card_index];
 288         card->capture = capture;
 289         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 290         card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
 291         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 292         card->surface = create_surface(format);
 293         card->resampling_queue.reset(new ResamplingQueue(card_index, OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
 294         card->capture->configure_card();
 295 }
 296
 297
 298 namespace {
 299
 300 int unwrap_timecode(uint16_t current_wrapped, int last)
 301 {
 302         uint16_t last_wrapped = last & 0xffff;
 303         if (current_wrapped > last_wrapped) {
 304                 return (last & ~0xffff) | current_wrapped;
 305         } else {
 306                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 307         }
 308 }
 309
 310 float find_peak(const float *samples, size_t num_samples)
 311 {
 312         float m = fabs(samples[0]);
 313         for (size_t i = 1; i < num_samples; ++i) {
 314                 m = max(m, fabs(samples[i]));
 315         }
 316         return m;
 317 }
 318
 319 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 320 {
 321         size_t num_samples = in.size() / 2;
 322         out_l->resize(num_samples);
 323         out_r->resize(num_samples);
 324
 325         const float *inptr = in.data();
 326         float *lptr = &(*out_l)[0];
 327         float *rptr = &(*out_r)[0];
 328         for (size_t i = 0; i < num_samples; ++i) {
 329                 *lptr++ = *inptr++;
 330                 *rptr++ = *inptr++;
 331         }
 332 }
 333
 334 }  // namespace
 335
 336 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 337                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 338                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 339 {
 340         CaptureCard *card = &cards[card_index];
 341
 342         if (is_mode_scanning[card_index]) {
 343                 if (video_format.has_signal) {
 344                         // Found a stable signal, so stop scanning.
 345                         is_mode_scanning[card_index] = false;
 346                 } else {
 347                         static constexpr double switch_time_s = 0.5;  // Should be enough time for the signal to stabilize.
 348                         timespec now;
 349                         clock_gettime(CLOCK_MONOTONIC, &now);
 350                         double sec_since_last_switch = (now.tv_sec - last_mode_scan_change[card_index].tv_sec) +
 351                                 1e-9 * (now.tv_nsec - last_mode_scan_change[card_index].tv_nsec);
 352                         if (sec_since_last_switch > switch_time_s) {
 353                                 // It isn't this mode; try the next one.
 354                                 mode_scanlist_index[card_index]++;
 355                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 356                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 357                                 last_mode_scan_change[card_index] = now;
 358                         }
 359                 }
 360         }
 361
 362         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 363
 364         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;
 365         if (num_samples > OUTPUT_FREQUENCY / 10) {
 366                 printf("Card %d: Dropping frame with implausible audio length (len=%d, offset=%d) [timecode=0x%04x video_len=%d video_offset=%d video_format=%x)\n",
 367                         card_index, int(audio_frame.len), int(audio_offset),
 368                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 369                 if (video_frame.owner) {
 370                         video_frame.owner->release_frame(video_frame);
 371                 }
 372                 if (audio_frame.owner) {
 373                         audio_frame.owner->release_frame(audio_frame);
 374                 }
 375                 return;
 376         }
 377
 378         int64_t local_pts = card->next_local_pts;
 379         int dropped_frames = 0;
 380         if (card->last_timecode != -1) {
 381                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 382         }
 383
 384         // Convert the audio to stereo fp32 and add it.
 385         vector<float> audio;
 386         audio.resize(num_samples * 2);
 387         switch (audio_format.bits_per_sample) {
 388         case 0:
 389                 assert(num_samples == 0);
 390                 break;
 391         case 24:
 392                 convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, audio_format.num_channels, num_samples);
 393                 break;
 394         case 32:
 395                 convert_fixed32_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, audio_format.num_channels, num_samples);
 396                 break;
 397         default:
 398                 fprintf(stderr, "Cannot handle audio with %u bits per sample\n", audio_format.bits_per_sample);
 399                 assert(false);
 400         }
 401
 402         // Add the audio.
 403         {
 404                 unique_lock<mutex> lock(card->audio_mutex);
 405
 406                 // Number of samples per frame if we need to insert silence.
 407                 // (Could be nonintegral, but resampling will save us then.)
 408                 int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 409
 410                 if (dropped_frames > MAX_FPS * 2) {
 411                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 412                                 card_index, card->last_timecode, timecode);
 413                         card->resampling_queue.reset(new ResamplingQueue(card_index, OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
 414                         dropped_frames = 0;
 415                 } else if (dropped_frames > 0) {
 416                         // Insert silence as needed.
 417                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 418                                 card_index, dropped_frames, timecode);
 419                         vector<float> silence(silence_samples * 2, 0.0f);
 420                         for (int i = 0; i < dropped_frames; ++i) {
 421                                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), silence.data(), silence_samples);
 422                                 // Note that if the format changed in the meantime, we have
 423                                 // no way of detecting that; we just have to assume the frame length
 424                                 // is always the same.
 425                                 local_pts += frame_length;
 426                         }
 427                 }
 428                 if (num_samples == 0) {
 429                         audio.resize(silence_samples * 2);
 430                         num_samples = silence_samples;
 431                 }
 432                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), audio.data(), num_samples);
 433                 card->next_local_pts = local_pts + frame_length;
 434         }
 435
 436         card->last_timecode = timecode;
 437
 438         // Done with the audio, so release it.
 439         if (audio_frame.owner) {
 440                 audio_frame.owner->release_frame(audio_frame);
 441         }
 442
 443         size_t expected_length = video_format.width * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom) * 2;
 444         if (video_frame.len - video_offset == 0 ||
 445             video_frame.len - video_offset != expected_length) {
 446                 if (video_frame.len != 0) {
 447                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 448                                 card_index, video_frame.len - video_offset, expected_length);
 449                 }
 450                 if (video_frame.owner) {
 451                         video_frame.owner->release_frame(video_frame);
 452                 }
 453
 454                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 455                 // so that pts can go up accordingly.
 456                 {
 457                         unique_lock<mutex> lock(bmusb_mutex);
 458                         CaptureCard::NewFrame new_frame;
 459                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 460                         new_frame.length = frame_length;
 461                         new_frame.interlaced = false;
 462                         new_frame.dropped_frames = dropped_frames;
 463                         card->new_frames.push(move(new_frame));
 464                         card->new_frames_changed.notify_all();
 465                 }
 466                 return;
 467         }
 468
 469         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 470
 471         unsigned num_fields = video_format.interlaced ? 2 : 1;
 472         timespec frame_upload_start;
 473         if (video_format.interlaced) {
 474                 // Send the two fields along as separate frames; the other side will need to add
 475                 // a deinterlacer to actually get this right.
 476                 assert(video_format.height % 2 == 0);
 477                 video_format.height /= 2;
 478                 assert(frame_length % 2 == 0);
 479                 frame_length /= 2;
 480                 num_fields = 2;
 481                 clock_gettime(CLOCK_MONOTONIC, &frame_upload_start);
 482         }
 483         userdata->last_interlaced = video_format.interlaced;
 484         userdata->last_has_signal = video_format.has_signal;
 485         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 486         userdata->last_frame_rate_den = video_format.frame_rate_den;
 487         RefCountedFrame frame(video_frame);
 488
 489         // Upload the textures.
 490         size_t cbcr_width = video_format.width / 2;
 491         size_t cbcr_offset = video_offset / 2;
 492         size_t y_offset = video_frame.size / 2 + video_offset / 2;
 493
 494         for (unsigned field = 0; field < num_fields; ++field) {
 495                 // Put the actual texture upload in a lambda that is executed in the main thread.
 496                 // It is entirely possible to do this in the same thread (and it might even be
 497                 // faster, depending on the GPU and driver), but it appears to be trickling
 498                 // driver bugs very easily.
 499                 //
 500                 // Note that this means we must hold on to the actual frame data in <userdata>
 501                 // until the upload command is run, but we hold on to <frame> much longer than that
 502                 // (in fact, all the way until we no longer use the texture in rendering).
 503                 auto upload_func = [field, video_format, y_offset, cbcr_offset, cbcr_width, userdata]() {
 504                         unsigned field_start_line = (field == 1) ? video_format.second_field_start : video_format.extra_lines_top + field * (video_format.height + 22);
 505
 506                         if (userdata->tex_y[field] == 0 ||
 507                             userdata->tex_cbcr[field] == 0 ||
 508                             video_format.width != userdata->last_width[field] ||
 509                             video_format.height != userdata->last_height[field]) {
 510                                 // We changed resolution since last use of this texture, so we need to create
 511                                 // a new object. Note that this each card has its own PBOFrameAllocator,
 512                                 // we don't need to worry about these flip-flopping between resolutions.
 513                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 514                                 check_error();
 515                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, video_format.height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 516                                 check_error();
 517                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 518                                 check_error();
 519                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, video_format.width, video_format.height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 520                                 check_error();
 521                                 userdata->last_width[field] = video_format.width;
 522                                 userdata->last_height[field] = video_format.height;
 523                         }
 524
 525                         GLuint pbo = userdata->pbo;
 526                         check_error();
 527                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
 528                         check_error();
 529
 530                         size_t field_y_start = y_offset + video_format.width * field_start_line;
 531                         size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 532
 533                         if (global_flags.flush_pbos) {
 534                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_y_start, video_format.width * video_format.height);
 535                                 check_error();
 536                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_cbcr_start, cbcr_width * video_format.height * sizeof(uint16_t));
 537                                 check_error();
 538                         }
 539
 540                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 541                         check_error();
 542                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, cbcr_width, video_format.height, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_cbcr_start));
 543                         check_error();
 544                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 545                         check_error();
 546                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, video_format.width, video_format.height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_y_start));
 547                         check_error();
 548                         glBindTexture(GL_TEXTURE_2D, 0);
 549                         check_error();
 550                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 551                         check_error();
 552                 };
 553
 554                 if (field == 1) {
 555                         // Don't upload the second field as fast as we can; wait until
 556                         // the field time has approximately passed. (Otherwise, we could
 557                         // get timing jitter against the other sources, and possibly also
 558                         // against the video display, although the latter is not as critical.)
 559                         // This requires our system clock to be reasonably close to the
 560                         // video clock, but that's not an unreasonable assumption.
 561                         timespec second_field_start;
 562                         second_field_start.tv_nsec = frame_upload_start.tv_nsec +
 563                                 frame_length * 1000000000 / TIMEBASE;
 564                         second_field_start.tv_sec = frame_upload_start.tv_sec +
 565                                 second_field_start.tv_nsec / 1000000000;
 566                         second_field_start.tv_nsec %= 1000000000;
 567
 568                         while (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
 569                                                &second_field_start, nullptr) == -1 &&
 570                                errno == EINTR) ;
 571                 }
 572
 573                 {
 574                         unique_lock<mutex> lock(bmusb_mutex);
 575                         CaptureCard::NewFrame new_frame;
 576                         new_frame.frame = frame;
 577                         new_frame.length = frame_length;
 578                         new_frame.field = field;
 579                         new_frame.interlaced = video_format.interlaced;
 580                         new_frame.upload_func = upload_func;
 581                         new_frame.dropped_frames = dropped_frames;
 582                         card->new_frames.push(move(new_frame));
 583                         card->new_frames_changed.notify_all();
 584                 }
 585         }
 586 }
 587
 588 void Mixer::thread_func()
 589 {
 590         eglBindAPI(EGL_OPENGL_API);
 591         QOpenGLContext *context = create_context(mixer_surface);
 592         if (!make_current(context, mixer_surface)) {
 593                 printf("oops\n");
 594                 exit(1);
 595         }
 596
 597         struct timespec start, now;
 598         clock_gettime(CLOCK_MONOTONIC, &start);
 599
 600         int frame = 0;
 601         int stats_dropped_frames = 0;
 602
 603         while (!should_quit) {
 604                 CaptureCard::NewFrame new_frames[MAX_CARDS];
 605                 bool has_new_frame[MAX_CARDS] = { false };
 606                 int num_samples[MAX_CARDS] = { 0 };
 607
 608                 // TODO: Add a timeout.
 609                 unsigned master_card_index = theme->map_signal(master_clock_channel);
 610                 assert(master_card_index < num_cards);
 611
 612                 get_one_frame_from_each_card(master_card_index, new_frames, has_new_frame, num_samples);
 613                 schedule_audio_resampling_tasks(new_frames[master_card_index].dropped_frames, num_samples[master_card_index], new_frames[master_card_index].length);
 614                 stats_dropped_frames += new_frames[master_card_index].dropped_frames;
 615                 send_audio_level_callback();
 616
 617                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 618                         if (card_index == master_card_index || !has_new_frame[card_index]) {
 619                                 continue;
 620                         }
 621                         if (new_frames[card_index].frame->len == 0) {
 622                                 ++new_frames[card_index].dropped_frames;
 623                         }
 624                         if (new_frames[card_index].dropped_frames > 0) {
 625                                 printf("Card %u dropped %d frames before this\n",
 626                                         card_index, int(new_frames[card_index].dropped_frames));
 627                         }
 628                 }
 629
 630                 // If the first card is reporting a corrupted or otherwise dropped frame,
 631                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 632                 if (new_frames[master_card_index].frame->len == 0) {
 633                         ++stats_dropped_frames;
 634                         pts_int += new_frames[master_card_index].length;
 635                         continue;
 636                 }
 637
 638                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 639                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
 640                                 continue;
 641
 642                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
 643                         assert(new_frame->frame != nullptr);
 644                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
 645                         check_error();
 646
 647                         // The new texture might need uploading before use.
 648                         if (new_frame->upload_func) {
 649                                 new_frame->upload_func();
 650                                 new_frame->upload_func = nullptr;
 651                         }
 652                 }
 653
 654                 int64_t duration = new_frames[master_card_index].length;
 655                 render_one_frame(duration);
 656                 ++frame;
 657                 pts_int += duration;
 658
 659                 clock_gettime(CLOCK_MONOTONIC, &now);
 660                 double elapsed = now.tv_sec - start.tv_sec +
 661                         1e-9 * (now.tv_nsec - start.tv_nsec);
 662                 if (frame % 100 == 0) {
 663                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
 664                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
 665                                 1e3 * elapsed / frame);
 666                 //      chain->print_phase_timing();
 667                 }
 668
 669                 if (should_cut.exchange(false)) {  // Test and clear.
 670                         video_encoder->do_cut(frame);
 671                 }
 672
 673 #if 0
 674                 // Reset every 100 frames, so that local variations in frame times
 675                 // (especially for the first few frames, when the shaders are
 676                 // compiled etc.) don't make it hard to measure for the entire
 677                 // remaining duration of the program.
 678                 if (frame == 10000) {
 679                         frame = 0;
 680                         start = now;
 681                 }
 682 #endif
 683                 check_error();
 684         }
 685
 686         resource_pool->clean_context();
 687 }
 688
 689 void Mixer::get_one_frame_from_each_card(unsigned master_card_index, CaptureCard::NewFrame new_frames[MAX_CARDS], bool has_new_frame[MAX_CARDS], int num_samples[MAX_CARDS])
 690 {
 691         // The first card is the master timer, so wait for it to have a new frame.
 692         unique_lock<mutex> lock(bmusb_mutex);
 693         cards[master_card_index].new_frames_changed.wait(lock, [this, master_card_index]{ return !cards[master_card_index].new_frames.empty(); });
 694
 695         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 696                 CaptureCard *card = &cards[card_index];
 697                 if (card->new_frames.empty()) {
 698                         assert(card_index != master_card_index);
 699                         card->queue_length_policy.update_policy(-1);
 700                         continue;
 701                 }
 702                 new_frames[card_index] = move(card->new_frames.front());
 703                 has_new_frame[card_index] = true;
 704                 card->new_frames.pop();
 705                 card->new_frames_changed.notify_all();
 706
 707                 int num_samples_times_timebase = OUTPUT_FREQUENCY * new_frames[card_index].length + card->fractional_samples;
 708                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
 709                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
 710                 assert(num_samples[card_index] >= 0);
 711
 712                 if (card_index == master_card_index) {
 713                         // We don't use the queue length policy for the master card,
 714                         // but we will if it stops being the master. Thus, clear out
 715                         // the policy in case we switch in the future.
 716                         card->queue_length_policy.reset(card_index);
 717                 } else {
 718                         // If we have excess frames compared to the policy for this card,
 719                         // drop frames from the head.
 720                         card->queue_length_policy.update_policy(card->new_frames.size());
 721                         while (card->new_frames.size() > card->queue_length_policy.get_safe_queue_length()) {
 722                                 card->new_frames.pop();
 723                         }
 724                 }
 725         }
 726 }
 727
 728 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame)
 729 {
 730         // Resample the audio as needed, including from previously dropped frames.
 731         assert(num_cards > 0);
 732         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
 733                 {
 734                         // Signal to the audio thread to process this frame.
 735                         unique_lock<mutex> lock(audio_mutex);
 736                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame});
 737                         audio_task_queue_changed.notify_one();
 738                 }
 739                 if (frame_num != dropped_frames) {
 740                         // For dropped frames, increase the pts. Note that if the format changed
 741                         // in the meantime, we have no way of detecting that; we just have to
 742                         // assume the frame length is always the same.
 743                         pts_int += length_per_frame;
 744                 }
 745         }
 746 }
 747
 748 void Mixer::render_one_frame(int64_t duration)
 749 {
 750         // Get the main chain from the theme, and set its state immediately.
 751         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
 752         EffectChain *chain = theme_main_chain.chain;
 753         theme_main_chain.setup_chain();
 754         //theme_main_chain.chain->enable_phase_timing(true);
 755
 756         GLuint y_tex, cbcr_tex;
 757         bool got_frame = video_encoder->begin_frame(&y_tex, &cbcr_tex);
 758         assert(got_frame);
 759
 760         // Render main chain.
 761         GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 762         GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 763         GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 764         check_error();
 765         chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 766         resource_pool->release_fbo(fbo);
 767
 768         subsample_chroma(cbcr_full_tex, cbcr_tex);
 769         resource_pool->release_2d_texture(cbcr_full_tex);
 770
 771         // Set the right state for rgba_tex.
 772         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 773         glBindTexture(GL_TEXTURE_2D, rgba_tex);
 774         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 775         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 776         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 777
 778         const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
 779         RefCountedGLsync fence = video_encoder->end_frame(pts_int + av_delay, duration, theme_main_chain.input_frames);
 780
 781         // The live frame just shows the RGBA texture we just rendered.
 782         // It owns rgba_tex now.
 783         DisplayFrame live_frame;
 784         live_frame.chain = display_chain.get();
 785         live_frame.setup_chain = [this, rgba_tex]{
 786                 display_input->set_texture_num(rgba_tex);
 787         };
 788         live_frame.ready_fence = fence;
 789         live_frame.input_frames = {};
 790         live_frame.temp_textures = { rgba_tex };
 791         output_channel[OUTPUT_LIVE].output_frame(live_frame);
 792
 793         // Set up preview and any additional channels.
 794         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 795                 DisplayFrame display_frame;
 796                 Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
 797                 display_frame.chain = chain.chain;
 798                 display_frame.setup_chain = chain.setup_chain;
 799                 display_frame.ready_fence = fence;
 800                 display_frame.input_frames = chain.input_frames;
 801                 display_frame.temp_textures = {};
 802                 output_channel[i].output_frame(display_frame);
 803         }
 804 }
 805
 806 void Mixer::send_audio_level_callback()
 807 {
 808         if (audio_level_callback == nullptr) {
 809                 return;
 810         }
 811
 812         unique_lock<mutex> lock(compressor_mutex);
 813         double loudness_s = r128.loudness_S();
 814         double loudness_i = r128.integrated();
 815         double loudness_range_low = r128.range_min();
 816         double loudness_range_high = r128.range_max();
 817
 818         audio_level_callback(loudness_s, 20.0 * log10(peak),
 819                 loudness_i, loudness_range_low, loudness_range_high,
 820                 gain_staging_db, 20.0 * log10(final_makeup_gain),
 821                 correlation.get_correlation());
 822 }
 823
 824 void Mixer::audio_thread_func()
 825 {
 826         while (!should_quit) {
 827                 AudioTask task;
 828
 829                 {
 830                         unique_lock<mutex> lock(audio_mutex);
 831                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
 832                         if (should_quit) {
 833                                 return;
 834                         }
 835                         task = audio_task_queue.front();
 836                         audio_task_queue.pop();
 837                 }
 838
 839                 process_audio_one_frame(task.pts_int, task.num_samples);
 840         }
 841 }
 842
 843 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples)
 844 {
 845         vector<float> samples_card;
 846         vector<float> samples_out;
 847
 848         // TODO: Allow mixing audio from several sources.
 849         unsigned selected_audio_card = theme->map_signal(audio_source_channel);
 850         assert(selected_audio_card < num_cards);
 851
 852         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 853                 samples_card.resize(num_samples * 2);
 854                 {
 855                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
 856                         cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], num_samples);
 857                 }
 858                 if (card_index == selected_audio_card) {
 859                         samples_out = move(samples_card);
 860                 }
 861         }
 862
 863         // Cut away everything under 120 Hz (or whatever the cutoff is);
 864         // we don't need it for voice, and it will reduce headroom
 865         // and confuse the compressor. (In particular, any hums at 50 or 60 Hz
 866         // should be dampened.)
 867         if (locut_enabled) {
 868                 locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
 869         }
 870
 871         // Apply a level compressor to get the general level right.
 872         // Basically, if it's over about -40 dBFS, we squeeze it down to that level
 873         // (or more precisely, near it, since we don't use infinite ratio),
 874         // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
 875         // entirely arbitrary, but from practical tests with speech, it seems to
 876         // put ut around -23 LUFS, so it's a reasonable starting point for later use.
 877         {
 878                 unique_lock<mutex> lock(compressor_mutex);
 879                 if (level_compressor_enabled) {
 880                         float threshold = 0.01f;   // -40 dBFS.
 881                         float ratio = 20.0f;
 882                         float attack_time = 0.5f;
 883                         float release_time = 20.0f;
 884                         float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f);  // +26 dB.
 885                         level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 886                         gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
 887                 } else {
 888                         // Just apply the gain we already had.
 889                         float g = pow(10.0f, gain_staging_db / 20.0f);
 890                         for (size_t i = 0; i < samples_out.size(); ++i) {
 891                                 samples_out[i] *= g;
 892                         }
 893                 }
 894         }
 895
 896 #if 0
 897         printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
 898                 level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
 899                 level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
 900                 20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
 901 #endif
 902
 903 //      float limiter_att, compressor_att;
 904
 905         // The real compressor.
 906         if (compressor_enabled) {
 907                 float threshold = pow(10.0f, compressor_threshold_dbfs / 20.0f);
 908                 float ratio = 20.0f;
 909                 float attack_time = 0.005f;
 910                 float release_time = 0.040f;
 911                 float makeup_gain = 2.0f;  // +6 dB.
 912                 compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 913 //              compressor_att = compressor.get_attenuation();
 914         }
 915
 916         // Finally a limiter at -4 dB (so, -10 dBFS) to take out the worst peaks only.
 917         // Note that since ratio is not infinite, we could go slightly higher than this.
 918         if (limiter_enabled) {
 919                 float threshold = pow(10.0f, limiter_threshold_dbfs / 20.0f);
 920                 float ratio = 30.0f;
 921                 float attack_time = 0.0f;  // Instant.
 922                 float release_time = 0.020f;
 923                 float makeup_gain = 1.0f;  // 0 dB.
 924                 limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 925 //              limiter_att = limiter.get_attenuation();
 926         }
 927
 928 //      printf("limiter=%+5.1f  compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
 929
 930         // Upsample 4x to find interpolated peak.
 931         peak_resampler.inp_data = samples_out.data();
 932         peak_resampler.inp_count = samples_out.size() / 2;
 933
 934         vector<float> interpolated_samples_out;
 935         interpolated_samples_out.resize(samples_out.size());
 936         while (peak_resampler.inp_count > 0) {  // About four iterations.
 937                 peak_resampler.out_data = &interpolated_samples_out[0];
 938                 peak_resampler.out_count = interpolated_samples_out.size() / 2;
 939                 peak_resampler.process();
 940                 size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
 941                 peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
 942                 peak_resampler.out_data = nullptr;
 943         }
 944
 945         // At this point, we are most likely close to +0 LU, but all of our
 946         // measurements have been on raw sample values, not R128 values.
 947         // So we have a final makeup gain to get us to +0 LU; the gain
 948         // adjustments required should be relatively small, and also, the
 949         // offset shouldn't change much (only if the type of audio changes
 950         // significantly). Thus, we shoot for updating this value basically
 951         // “whenever we process buffers”, since the R128 calculation isn't exactly
 952         // something we get out per-sample.
 953         //
 954         // Note that there's a feedback loop here, so we choose a very slow filter
 955         // (half-time of 100 seconds).
 956         double target_loudness_factor, alpha;
 957         {
 958                 unique_lock<mutex> lock(compressor_mutex);
 959                 double loudness_lu = r128.loudness_M() - ref_level_lufs;
 960                 double current_makeup_lu = 20.0f * log10(final_makeup_gain);
 961                 target_loudness_factor = pow(10.0f, -loudness_lu / 20.0f);
 962
 963                 // If we're outside +/- 5 LU uncorrected, we don't count it as
 964                 // a normal signal (probably silence) and don't change the
 965                 // correction factor; just apply what we already have.
 966                 if (fabs(loudness_lu - current_makeup_lu) >= 5.0 || !final_makeup_gain_auto) {
 967                         alpha = 0.0;
 968                 } else {
 969                         // Formula adapted from
 970                         // https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter.
 971                         const double half_time_s = 100.0;
 972                         const double fc_mul_2pi_delta_t = 1.0 / (half_time_s * OUTPUT_FREQUENCY);
 973                         alpha = fc_mul_2pi_delta_t / (fc_mul_2pi_delta_t + 1.0);
 974                 }
 975
 976                 double m = final_makeup_gain;
 977                 for (size_t i = 0; i < samples_out.size(); i += 2) {
 978                         samples_out[i + 0] *= m;
 979                         samples_out[i + 1] *= m;
 980                         m += (target_loudness_factor - m) * alpha;
 981                 }
 982                 final_makeup_gain = m;
 983         }
 984
 985         // Find R128 levels and L/R correlation.
 986         vector<float> left, right;
 987         deinterleave_samples(samples_out, &left, &right);
 988         float *ptrs[] = { left.data(), right.data() };
 989         {
 990                 unique_lock<mutex> lock(compressor_mutex);
 991                 r128.process(left.size(), ptrs);
 992                 correlation.process_samples(samples_out);
 993         }
 994
 995         // Send the samples to the sound card.
 996         if (alsa) {
 997                 alsa->write(samples_out);
 998         }
 999
1000         // And finally add them to the output.
1001         video_encoder->add_audio(frame_pts_int, move(samples_out));
1002 }
1003
1004 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
1005 {
1006         GLuint vao;
1007         glGenVertexArrays(1, &vao);
1008         check_error();
1009
1010         glBindVertexArray(vao);
1011         check_error();
1012
1013         // Extract Cb/Cr.
1014         GLuint fbo = resource_pool->create_fbo(dst_tex);
1015         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
1016         glViewport(0, 0, WIDTH/2, HEIGHT/2);
1017         check_error();
1018
1019         glUseProgram(cbcr_program_num);
1020         check_error();
1021
1022         glActiveTexture(GL_TEXTURE0);
1023         check_error();
1024         glBindTexture(GL_TEXTURE_2D, src_tex);
1025         check_error();
1026         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1027         check_error();
1028         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1029         check_error();
1030         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1031         check_error();
1032
1033         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
1034         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
1035
1036         glBindBuffer(GL_ARRAY_BUFFER, cbcr_vbo);
1037         check_error();
1038
1039         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
1040                 glEnableVertexAttribArray(attr_index);
1041                 check_error();
1042                 glVertexAttribPointer(attr_index, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
1043                 check_error();
1044         }
1045
1046         glDrawArrays(GL_TRIANGLES, 0, 3);
1047         check_error();
1048
1049         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
1050                 glDisableVertexAttribArray(attr_index);
1051                 check_error();
1052         }
1053
1054         glUseProgram(0);
1055         check_error();
1056         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1057         check_error();
1058
1059         resource_pool->release_fbo(fbo);
1060         glDeleteVertexArrays(1, &vao);
1061 }
1062
1063 void Mixer::release_display_frame(DisplayFrame *frame)
1064 {
1065         for (GLuint texnum : frame->temp_textures) {
1066                 resource_pool->release_2d_texture(texnum);
1067         }
1068         frame->temp_textures.clear();
1069         frame->ready_fence.reset();
1070         frame->input_frames.clear();
1071 }
1072
1073 void Mixer::start()
1074 {
1075         mixer_thread = thread(&Mixer::thread_func, this);
1076         audio_thread = thread(&Mixer::audio_thread_func, this);
1077 }
1078
1079 void Mixer::quit()
1080 {
1081         should_quit = true;
1082         audio_task_queue_changed.notify_one();
1083         mixer_thread.join();
1084         audio_thread.join();
1085 }
1086
1087 void Mixer::transition_clicked(int transition_num)
1088 {
1089         theme->transition_clicked(transition_num, pts());
1090 }
1091
1092 void Mixer::channel_clicked(int preview_num)
1093 {
1094         theme->channel_clicked(preview_num);
1095 }
1096
1097 void Mixer::reset_meters()
1098 {
1099         peak_resampler.reset();
1100         peak = 0.0f;
1101         r128.reset();
1102         r128.integr_start();
1103         correlation.reset();
1104 }
1105
1106 void Mixer::start_mode_scanning(unsigned card_index)
1107 {
1108         assert(card_index < num_cards);
1109         if (is_mode_scanning[card_index]) {
1110                 return;
1111         }
1112         is_mode_scanning[card_index] = true;
1113         mode_scanlist[card_index].clear();
1114         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1115                 mode_scanlist[card_index].push_back(mode.first);
1116         }
1117         assert(!mode_scanlist[card_index].empty());
1118         mode_scanlist_index[card_index] = 0;
1119         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1120         clock_gettime(CLOCK_MONOTONIC, &last_mode_scan_change[card_index]);
1121 }
1122
1123 Mixer::OutputChannel::~OutputChannel()
1124 {
1125         if (has_current_frame) {
1126                 parent->release_display_frame(&current_frame);
1127         }
1128         if (has_ready_frame) {
1129                 parent->release_display_frame(&ready_frame);
1130         }
1131 }
1132
1133 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1134 {
1135         // Store this frame for display. Remove the ready frame if any
1136         // (it was seemingly never used).
1137         {
1138                 unique_lock<mutex> lock(frame_mutex);
1139                 if (has_ready_frame) {
1140                         parent->release_display_frame(&ready_frame);
1141                 }
1142                 ready_frame = frame;
1143                 has_ready_frame = true;
1144         }
1145
1146         if (new_frame_ready_callback) {
1147                 new_frame_ready_callback();
1148         }
1149
1150         // Reduce the number of callbacks by filtering duplicates. The reason
1151         // why we bother doing this is that Qt seemingly can get into a state
1152         // where its builds up an essentially unbounded queue of signals,
1153         // consuming more and more memory, and there's no good way of collapsing
1154         // user-defined signals or limiting the length of the queue.
1155         if (transition_names_updated_callback) {
1156                 vector<string> transition_names = global_mixer->get_transition_names();
1157                 bool changed = false;
1158                 if (transition_names.size() != last_transition_names.size()) {
1159                         changed = true;
1160                 } else {
1161                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1162                                 if (transition_names[i] != last_transition_names[i]) {
1163                                         changed = true;
1164                                         break;
1165                                 }
1166                         }
1167                 }
1168                 if (changed) {
1169                         transition_names_updated_callback(transition_names);
1170                         last_transition_names = transition_names;
1171                 }
1172         }
1173         if (name_updated_callback) {
1174                 string name = global_mixer->get_channel_name(channel);
1175                 if (name != last_name) {
1176                         name_updated_callback(name);
1177                         last_name = name;
1178                 }
1179         }
1180         if (color_updated_callback) {
1181                 string color = global_mixer->get_channel_color(channel);
1182                 if (color != last_color) {
1183                         color_updated_callback(color);
1184                         last_color = color;
1185                 }
1186         }
1187 }
1188
1189 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1190 {
1191         unique_lock<mutex> lock(frame_mutex);
1192         if (!has_current_frame && !has_ready_frame) {
1193                 return false;
1194         }
1195
1196         if (has_current_frame && has_ready_frame) {
1197                 // We have a new ready frame. Toss the current one.
1198                 parent->release_display_frame(&current_frame);
1199                 has_current_frame = false;
1200         }
1201         if (has_ready_frame) {
1202                 assert(!has_current_frame);
1203                 current_frame = ready_frame;
1204                 ready_frame.ready_fence.reset();  // Drop the refcount.
1205                 ready_frame.input_frames.clear();  // Drop the refcounts.
1206                 has_current_frame = true;
1207                 has_ready_frame = false;
1208         }
1209
1210         *frame = current_frame;
1211         return true;
1212 }
1213
1214 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1215 {
1216         new_frame_ready_callback = callback;
1217 }
1218
1219 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1220 {
1221         transition_names_updated_callback = callback;
1222 }
1223
1224 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1225 {
1226         name_updated_callback = callback;
1227 }
1228
1229 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1230 {
1231         color_updated_callback = callback;
1232 }
1233
1234 mutex RefCountedGLsync::fence_lock;