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 <init.h>
   8 #include <movit/effect_chain.h>
   9 #include <movit/effect_util.h>
  10 #include <movit/flat_input.h>
  11 #include <movit/image_format.h>
  12 #include <movit/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
  30 #include "bmusb/bmusb.h"
  31 #include "context.h"
  32 #include "defs.h"
  33 #include "h264encode.h"
  34 #include "pbo_frame_allocator.h"
  35 #include "ref_counted_gl_sync.h"
  36 #include "timebase.h"
  37
  38 class QOpenGLContext;
  39
  40 using namespace movit;
  41 using namespace std;
  42 using namespace std::placeholders;
  43
  44 Mixer *global_mixer = nullptr;
  45
  46 namespace {
  47
  48 void convert_fixed24_to_fp32(float *dst, size_t out_channels, const uint8_t *src, size_t in_channels, size_t num_samples)
  49 {
  50         for (size_t i = 0; i < num_samples; ++i) {
  51                 for (size_t j = 0; j < out_channels; ++j) {
  52                         uint32_t s1 = *src++;
  53                         uint32_t s2 = *src++;
  54                         uint32_t s3 = *src++;
  55                         uint32_t s = s1 | (s1 << 8) | (s2 << 16) | (s3 << 24);
  56                         dst[i * out_channels + j] = int(s) * (1.0f / 4294967296.0f);
  57                 }
  58                 src += 3 * (in_channels - out_channels);
  59         }
  60 }
  61
  62 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  63 {
  64         if (interlaced) {
  65                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  66                         input_state->buffered_frames[card_index][frame_num] =
  67                                 input_state->buffered_frames[card_index][frame_num - 1];
  68                 }
  69                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  70         } else {
  71                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  72                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  73                 }
  74         }
  75 }
  76
  77
  78 }  // namespace
  79
  80 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
  81         : httpd(LOCAL_DUMP_FILE_NAME, WIDTH, HEIGHT),
  82           num_cards(num_cards),
  83           mixer_surface(create_surface(format)),
  84           h264_encoder_surface(create_surface(format)),
  85           level_compressor(OUTPUT_FREQUENCY),
  86           limiter(OUTPUT_FREQUENCY),
  87           compressor(OUTPUT_FREQUENCY)
  88 {
  89         httpd.start(9095);
  90
  91         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
  92         check_error();
  93
  94         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
  95         // will be halved when sampling them, and we need to compensate here.
  96         movit_texel_subpixel_precision /= 2.0;
  97
  98         resource_pool.reset(new ResourcePool);
  99         theme.reset(new Theme("theme.lua", resource_pool.get(), num_cards));
 100         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 101                 output_channel[i].parent = this;
 102         }
 103
 104         ImageFormat inout_format;
 105         inout_format.color_space = COLORSPACE_sRGB;
 106         inout_format.gamma_curve = GAMMA_sRGB;
 107
 108         // Display chain; shows the live output produced by the main chain (its RGBA version).
 109         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 110         check_error();
 111         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 112         display_chain->add_input(display_input);
 113         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 114         display_chain->set_dither_bits(0);  // Don't bother.
 115         display_chain->finalize();
 116
 117         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
 118
 119         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 120                 printf("Configuring card %d...\n", card_index);
 121                 CaptureCard *card = &cards[card_index];
 122                 card->usb = new BMUSBCapture(card_index);
 123                 card->usb->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 124                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
 125                 card->usb->set_video_frame_allocator(card->frame_allocator.get());
 126                 card->surface = create_surface(format);
 127                 card->usb->set_dequeue_thread_callbacks(
 128                         [card]{
 129                                 eglBindAPI(EGL_OPENGL_API);
 130                                 card->context = create_context(card->surface);
 131                                 if (!make_current(card->context, card->surface)) {
 132                                         printf("failed to create bmusb context\n");
 133                                         exit(1);
 134                                 }
 135                         },
 136                         [this]{
 137                                 resource_pool->clean_context();
 138                         });
 139                 card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
 140                 card->usb->configure_card();
 141         }
 142
 143         BMUSBCapture::start_bm_thread();
 144
 145         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 146                 cards[card_index].usb->start_bm_capture();
 147         }
 148
 149         //chain->enable_phase_timing(true);
 150
 151         // Set up stuff for NV12 conversion.
 152
 153         // Cb/Cr shader.
 154         string cbcr_vert_shader = read_file("vs-cbcr.130.vert");
 155         string cbcr_frag_shader =
 156                 "#version 130 \n"
 157                 "in vec2 tc0; \n"
 158                 "uniform sampler2D cbcr_tex; \n"
 159                 "void main() { \n"
 160                 "    gl_FragColor = texture2D(cbcr_tex, tc0); \n"
 161                 "} \n";
 162         vector<string> frag_shader_outputs;
 163         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
 164
 165         r128.init(2, OUTPUT_FREQUENCY);
 166         r128.integr_start();
 167
 168         locut.init(FILTER_HPF, 2);
 169
 170         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
 171         // and there's a limit to how important the peak meter is.
 172         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16);
 173
 174         alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 175 }
 176
 177 Mixer::~Mixer()
 178 {
 179         resource_pool->release_glsl_program(cbcr_program_num);
 180         BMUSBCapture::stop_bm_thread();
 181
 182         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 183                 {
 184                         unique_lock<mutex> lock(bmusb_mutex);
 185                         cards[card_index].should_quit = true;  // Unblock thread.
 186                         cards[card_index].new_data_ready_changed.notify_all();
 187                 }
 188                 cards[card_index].usb->stop_dequeue_thread();
 189         }
 190
 191         h264_encoder.reset(nullptr);
 192 }
 193
 194 namespace {
 195
 196 int unwrap_timecode(uint16_t current_wrapped, int last)
 197 {
 198         uint16_t last_wrapped = last & 0xffff;
 199         if (current_wrapped > last_wrapped) {
 200                 return (last & ~0xffff) | current_wrapped;
 201         } else {
 202                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 203         }
 204 }
 205
 206 float find_peak(const float *samples, size_t num_samples)
 207 {
 208         float m = fabs(samples[0]);
 209         for (size_t i = 1; i < num_samples; ++i) {
 210                 m = std::max(m, fabs(samples[i]));
 211         }
 212         return m;
 213 }
 214
 215 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 216 {
 217         size_t num_samples = in.size() / 2;
 218         out_l->resize(num_samples);
 219         out_r->resize(num_samples);
 220
 221         const float *inptr = in.data();
 222         float *lptr = &(*out_l)[0];
 223         float *rptr = &(*out_r)[0];
 224         for (size_t i = 0; i < num_samples; ++i) {
 225                 *lptr++ = *inptr++;
 226                 *rptr++ = *inptr++;
 227         }
 228 }
 229
 230 }  // namespace
 231
 232 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 233                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 234                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
 235 {
 236         CaptureCard *card = &cards[card_index];
 237
 238         unsigned width, height, second_field_start, frame_rate_nom, frame_rate_den, extra_lines_top, extra_lines_bottom;
 239         bool interlaced;
 240
 241         decode_video_format(video_format, &width, &height, &second_field_start, &extra_lines_top, &extra_lines_bottom,
 242                             &frame_rate_nom, &frame_rate_den, &interlaced);  // Ignore return value for now.
 243         int64_t frame_length = TIMEBASE * frame_rate_den / frame_rate_nom;
 244
 245         size_t num_samples = (audio_frame.len >= audio_offset) ? (audio_frame.len - audio_offset) / 8 / 3 : 0;
 246         if (num_samples > OUTPUT_FREQUENCY / 10) {
 247                 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",
 248                         card_index, int(audio_frame.len), int(audio_offset),
 249                         timecode, int(video_frame.len), int(video_offset), video_format);
 250                 if (video_frame.owner) {
 251                         video_frame.owner->release_frame(video_frame);
 252                 }
 253                 if (audio_frame.owner) {
 254                         audio_frame.owner->release_frame(audio_frame);
 255                 }
 256                 return;
 257         }
 258
 259         int64_t local_pts = card->next_local_pts;
 260         int dropped_frames = 0;
 261         if (card->last_timecode != -1) {
 262                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 263         }
 264
 265         // Convert the audio to stereo fp32 and add it.
 266         vector<float> audio;
 267         audio.resize(num_samples * 2);
 268         convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
 269
 270         // Add the audio.
 271         {
 272                 unique_lock<mutex> lock(card->audio_mutex);
 273
 274                 // Number of samples per frame if we need to insert silence.
 275                 // (Could be nonintegral, but resampling will save us then.)
 276                 int silence_samples = OUTPUT_FREQUENCY * frame_rate_den / frame_rate_nom;
 277
 278                 if (dropped_frames > MAX_FPS * 2) {
 279                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 280                                 card_index, card->last_timecode, timecode);
 281                         card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
 282                         dropped_frames = 0;
 283                 } else if (dropped_frames > 0) {
 284                         // Insert silence as needed.
 285                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 286                                 card_index, dropped_frames, timecode);
 287                         vector<float> silence(silence_samples * 2, 0.0f);
 288                         for (int i = 0; i < dropped_frames; ++i) {
 289                                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), silence.data(), silence_samples);
 290                                 // Note that if the format changed in the meantime, we have
 291                                 // no way of detecting that; we just have to assume the frame length
 292                                 // is always the same.
 293                                 local_pts += frame_length;
 294                         }
 295                 }
 296                 if (num_samples == 0) {
 297                         audio.resize(silence_samples * 2);
 298                         num_samples = silence_samples;
 299                 }
 300                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), audio.data(), num_samples);
 301                 card->next_local_pts = local_pts + frame_length;
 302         }
 303
 304         card->last_timecode = timecode;
 305
 306         // Done with the audio, so release it.
 307         if (audio_frame.owner) {
 308                 audio_frame.owner->release_frame(audio_frame);
 309         }
 310
 311         {
 312                 // Wait until the previous frame was consumed.
 313                 unique_lock<mutex> lock(bmusb_mutex);
 314                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
 315                 if (card->should_quit) return;
 316         }
 317
 318         if (video_frame.len - video_offset == 0 ||
 319             video_frame.len - video_offset != size_t(width * (height + extra_lines_top + extra_lines_bottom) * 2)) {
 320                 if (video_frame.len != 0) {
 321                         printf("Card %d: Dropping video frame with wrong length (%ld)\n",
 322                                 card_index, video_frame.len - video_offset);
 323                 }
 324                 if (video_frame.owner) {
 325                         video_frame.owner->release_frame(video_frame);
 326                 }
 327
 328                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 329                 // so that pts can go up accordingly.
 330                 {
 331                         unique_lock<mutex> lock(bmusb_mutex);
 332                         card->new_data_ready = true;
 333                         card->new_frame = RefCountedFrame(FrameAllocator::Frame());
 334                         card->new_frame_length = frame_length;
 335                         card->new_frame_interlaced = false;
 336                         card->new_data_ready_fence = nullptr;
 337                         card->dropped_frames = dropped_frames;
 338                         card->new_data_ready_changed.notify_all();
 339                 }
 340                 return;
 341         }
 342
 343         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 344
 345         unsigned num_fields = interlaced ? 2 : 1;
 346         timespec frame_upload_start;
 347         if (interlaced) {
 348                 // NOTE: This isn't deinterlacing. This is just sending the two fields along
 349                 // as separate frames without considering anything like the half-field offset.
 350                 // We'll need to add a proper deinterlacer on the receiving side to get this right.
 351                 assert(height % 2 == 0);
 352                 height /= 2;
 353                 assert(frame_length % 2 == 0);
 354                 frame_length /= 2;
 355                 num_fields = 2;
 356                 clock_gettime(CLOCK_MONOTONIC, &frame_upload_start);
 357         }
 358         RefCountedFrame new_frame(video_frame);
 359
 360         // Upload the textures.
 361         size_t cbcr_width = width / 2;
 362         size_t cbcr_offset = video_offset / 2;
 363         size_t y_offset = video_frame.size / 2 + video_offset / 2;
 364
 365         for (unsigned field = 0; field < num_fields; ++field) {
 366                 unsigned field_start_line = (field == 1) ? second_field_start : extra_lines_top + field * (height + 22);
 367
 368                 if (userdata->tex_y[field] == 0 ||
 369                     userdata->tex_cbcr[field] == 0 ||
 370                     width != userdata->last_width[field] ||
 371                     height != userdata->last_height[field]) {
 372                         // We changed resolution since last use of this texture, so we need to create
 373                         // a new object. Note that this each card has its own PBOFrameAllocator,
 374                         // we don't need to worry about these flip-flopping between resolutions.
 375                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 376                         check_error();
 377                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 378                         check_error();
 379                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 380                         check_error();
 381                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 382                         check_error();
 383                         userdata->last_width[field] = width;
 384                         userdata->last_height[field] = height;
 385                 }
 386
 387                 GLuint pbo = userdata->pbo;
 388                 check_error();
 389                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
 390                 check_error();
 391                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, video_frame.size);
 392                 check_error();
 393                 //glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 394                 //check_error();
 395
 396                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 397                 check_error();
 398                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, cbcr_width, height, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t)));
 399                 check_error();
 400                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 401                 check_error();
 402                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(y_offset + width * field_start_line));
 403                 check_error();
 404                 glBindTexture(GL_TEXTURE_2D, 0);
 405                 check_error();
 406                 GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 407                 check_error();
 408                 assert(fence != nullptr);
 409
 410                 if (field == 1) {
 411                         // Don't upload the second field as fast as we can; wait until
 412                         // the field time has approximately passed. (Otherwise, we could
 413                         // get timing jitter against the other sources, and possibly also
 414                         // against the video display, although the latter is not as critical.)
 415                         // This requires our system clock to be reasonably close to the
 416                         // video clock, but that's not an unreasonable assumption.
 417                         timespec second_field_start;
 418                         second_field_start.tv_nsec = frame_upload_start.tv_nsec +
 419                                 frame_length * 1000000000 / TIMEBASE;
 420                         second_field_start.tv_sec = frame_upload_start.tv_sec +
 421                                 second_field_start.tv_nsec / 1000000000;
 422                         second_field_start.tv_nsec %= 1000000000;
 423
 424                         while (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
 425                                                &second_field_start, nullptr) == -1 &&
 426                                errno == EINTR) ;
 427                 }
 428
 429                 {
 430                         unique_lock<mutex> lock(bmusb_mutex);
 431                         card->new_data_ready = true;
 432                         card->new_frame = new_frame;
 433                         card->new_frame_length = frame_length;
 434                         card->new_frame_field = field;
 435                         card->new_frame_interlaced = interlaced;
 436                         card->new_data_ready_fence = fence;
 437                         card->dropped_frames = dropped_frames;
 438                         card->new_data_ready_changed.notify_all();
 439
 440                         if (field != num_fields - 1) {
 441                                 // Wait until the previous frame was consumed.
 442                                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
 443                                 if (card->should_quit) return;
 444                         }
 445                 }
 446         }
 447 }
 448
 449 void Mixer::thread_func()
 450 {
 451         eglBindAPI(EGL_OPENGL_API);
 452         QOpenGLContext *context = create_context(mixer_surface);
 453         if (!make_current(context, mixer_surface)) {
 454                 printf("oops\n");
 455                 exit(1);
 456         }
 457
 458         struct timespec start, now;
 459         clock_gettime(CLOCK_MONOTONIC, &start);
 460
 461         int frame = 0;
 462         int stats_dropped_frames = 0;
 463
 464         while (!should_quit) {
 465                 CaptureCard card_copy[MAX_CARDS];
 466                 int num_samples[MAX_CARDS];
 467
 468                 {
 469                         unique_lock<mutex> lock(bmusb_mutex);
 470
 471                         // The first card is the master timer, so wait for it to have a new frame.
 472                         // TODO: Make configurable, and with a timeout.
 473                         cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
 474
 475                         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 476                                 CaptureCard *card = &cards[card_index];
 477                                 card_copy[card_index].usb = card->usb;
 478                                 card_copy[card_index].new_data_ready = card->new_data_ready;
 479                                 card_copy[card_index].new_frame = card->new_frame;
 480                                 card_copy[card_index].new_frame_length = card->new_frame_length;
 481                                 card_copy[card_index].new_frame_field = card->new_frame_field;
 482                                 card_copy[card_index].new_frame_interlaced = card->new_frame_interlaced;
 483                                 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
 484                                 card_copy[card_index].dropped_frames = card->dropped_frames;
 485                                 card->new_data_ready = false;
 486                                 card->new_data_ready_changed.notify_all();
 487
 488                                 int num_samples_times_timebase = OUTPUT_FREQUENCY * card->new_frame_length + card->fractional_samples;
 489                                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
 490                                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
 491                                 assert(num_samples[card_index] >= 0);
 492                         }
 493                 }
 494
 495                 // Resample the audio as needed, including from previously dropped frames.
 496                 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
 497                         {
 498                                 // Signal to the audio thread to process this frame.
 499                                 unique_lock<mutex> lock(audio_mutex);
 500                                 audio_task_queue.push(AudioTask{pts_int, num_samples[0]});
 501                                 audio_task_queue_changed.notify_one();
 502                         }
 503                         if (frame_num != card_copy[0].dropped_frames) {
 504                                 // For dropped frames, increase the pts. Note that if the format changed
 505                                 // in the meantime, we have no way of detecting that; we just have to
 506                                 // assume the frame length is always the same.
 507                                 ++stats_dropped_frames;
 508                                 pts_int += card_copy[0].new_frame_length;
 509                         }
 510                 }
 511
 512                 if (audio_level_callback != nullptr) {
 513                         unique_lock<mutex> lock(r128_mutex);
 514                         double loudness_s = r128.loudness_S();
 515                         double loudness_i = r128.integrated();
 516                         double loudness_range_low = r128.range_min();
 517                         double loudness_range_high = r128.range_max();
 518
 519                         audio_level_callback(loudness_s, 20.0 * log10(peak),
 520                                              loudness_i, loudness_range_low, loudness_range_high,
 521                                              last_gain_staging_db);
 522                 }
 523
 524                 for (unsigned card_index = 1; card_index < num_cards; ++card_index) {
 525                         if (card_copy[card_index].new_data_ready && card_copy[card_index].new_frame->len == 0) {
 526                                 ++card_copy[card_index].dropped_frames;
 527                         }
 528                         if (card_copy[card_index].dropped_frames > 0) {
 529                                 printf("Card %u dropped %d frames before this\n",
 530                                         card_index, int(card_copy[card_index].dropped_frames));
 531                         }
 532                 }
 533
 534                 // If the first card is reporting a corrupted or otherwise dropped frame,
 535                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 536                 if (card_copy[0].new_frame->len == 0) {
 537                         ++stats_dropped_frames;
 538                         pts_int += card_copy[0].new_frame_length;
 539                         continue;
 540                 }
 541
 542                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 543                         CaptureCard *card = &card_copy[card_index];
 544                         if (!card->new_data_ready || card->new_frame->len == 0)
 545                                 continue;
 546
 547                         assert(card->new_frame != nullptr);
 548                         insert_new_frame(card->new_frame, card->new_frame_field, card->new_frame_interlaced, card_index, &input_state);
 549                         check_error();
 550
 551                         // The new texture might still be uploaded,
 552                         // tell the GPU to wait until it's there.
 553                         if (card->new_data_ready_fence) {
 554                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
 555                                 check_error();
 556                                 glDeleteSync(card->new_data_ready_fence);
 557                                 check_error();
 558                         }
 559                 }
 560
 561                 // Get the main chain from the theme, and set its state immediately.
 562                 Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
 563                 EffectChain *chain = theme_main_chain.chain;
 564                 theme_main_chain.setup_chain();
 565
 566                 GLuint y_tex, cbcr_tex;
 567                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
 568                 assert(got_frame);
 569
 570                 // Render main chain.
 571                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 572                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 573                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 574                 check_error();
 575                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 576                 resource_pool->release_fbo(fbo);
 577
 578                 subsample_chroma(cbcr_full_tex, cbcr_tex);
 579                 resource_pool->release_2d_texture(cbcr_full_tex);
 580
 581                 // Set the right state for rgba_tex.
 582                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
 583                 glBindTexture(GL_TEXTURE_2D, rgba_tex);
 584                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 585                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 586                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 587
 588                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 589                 check_error();
 590
 591                 const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
 592                 h264_encoder->end_frame(fence, pts_int + av_delay, theme_main_chain.input_frames);
 593                 ++frame;
 594                 pts_int += card_copy[0].new_frame_length;
 595
 596                 // The live frame just shows the RGBA texture we just rendered.
 597                 // It owns rgba_tex now.
 598                 DisplayFrame live_frame;
 599                 live_frame.chain = display_chain.get();
 600                 live_frame.setup_chain = [this, rgba_tex]{
 601                         display_input->set_texture_num(rgba_tex);
 602                 };
 603                 live_frame.ready_fence = fence;
 604                 live_frame.input_frames = {};
 605                 live_frame.temp_textures = { rgba_tex };
 606                 output_channel[OUTPUT_LIVE].output_frame(live_frame);
 607
 608                 // Set up preview and any additional channels.
 609                 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 610                         DisplayFrame display_frame;
 611                         Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
 612                         display_frame.chain = chain.chain;
 613                         display_frame.setup_chain = chain.setup_chain;
 614                         display_frame.ready_fence = fence;
 615                         display_frame.input_frames = chain.input_frames;
 616                         display_frame.temp_textures = {};
 617                         output_channel[i].output_frame(display_frame);
 618                 }
 619
 620                 clock_gettime(CLOCK_MONOTONIC, &now);
 621                 double elapsed = now.tv_sec - start.tv_sec +
 622                         1e-9 * (now.tv_nsec - start.tv_nsec);
 623                 if (frame % 100 == 0) {
 624                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
 625                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
 626                                 1e3 * elapsed / frame);
 627                 //      chain->print_phase_timing();
 628                 }
 629
 630 #if 0
 631                 // Reset every 100 frames, so that local variations in frame times
 632                 // (especially for the first few frames, when the shaders are
 633                 // compiled etc.) don't make it hard to measure for the entire
 634                 // remaining duration of the program.
 635                 if (frame == 10000) {
 636                         frame = 0;
 637                         start = now;
 638                 }
 639 #endif
 640                 check_error();
 641         }
 642
 643         resource_pool->clean_context();
 644 }
 645
 646 void Mixer::audio_thread_func()
 647 {
 648         while (!should_quit) {
 649                 AudioTask task;
 650
 651                 {
 652                         unique_lock<mutex> lock(audio_mutex);
 653                         audio_task_queue_changed.wait(lock, [this]{ return !audio_task_queue.empty(); });
 654                         task = audio_task_queue.front();
 655                         audio_task_queue.pop();
 656                 }
 657
 658                 process_audio_one_frame(task.pts_int, task.num_samples);
 659         }
 660 }
 661
 662 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples)
 663 {
 664         vector<float> samples_card;
 665         vector<float> samples_out;
 666         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 667                 samples_card.resize(num_samples * 2);
 668                 {
 669                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
 670                         if (!cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], num_samples)) {
 671                                 printf("Card %d reported previous underrun.\n", card_index);
 672                         }
 673                 }
 674                 // TODO: Allow using audio from the other card(s) as well.
 675                 if (card_index == 0) {
 676                         samples_out = move(samples_card);
 677                 }
 678         }
 679
 680         // Cut away everything under 120 Hz (or whatever the cutoff is);
 681         // we don't need it for voice, and it will reduce headroom
 682         // and confuse the compressor. (In particular, any hums at 50 or 60 Hz
 683         // should be dampened.)
 684         locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
 685
 686         // Apply a level compressor to get the general level right.
 687         // Basically, if it's over about -40 dBFS, we squeeze it down to that level
 688         // (or more precisely, near it, since we don't use infinite ratio),
 689         // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
 690         // entirely arbitrary, but from practical tests with speech, it seems to
 691         // put ut around -23 LUFS, so it's a reasonable starting point for later use.
 692         float ref_level_dbfs = -14.0f;
 693         {
 694                 float threshold = 0.01f;   // -40 dBFS.
 695                 float ratio = 20.0f;
 696                 float attack_time = 0.5f;
 697                 float release_time = 20.0f;
 698                 float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f);  // +26 dB.
 699                 level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 700                 last_gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
 701         }
 702
 703 #if 0
 704         printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
 705                 level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
 706                 level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
 707                 20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
 708 #endif
 709
 710 //      float limiter_att, compressor_att;
 711
 712         // The real compressor.
 713         if (compressor_enabled) {
 714                 float threshold = pow(10.0f, compressor_threshold_dbfs / 20.0f);
 715                 float ratio = 20.0f;
 716                 float attack_time = 0.005f;
 717                 float release_time = 0.040f;
 718                 float makeup_gain = 2.0f;  // +6 dB.
 719                 compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 720 //              compressor_att = compressor.get_attenuation();
 721         }
 722
 723         // Finally a limiter at -4 dB (so, -10 dBFS) to take out the worst peaks only.
 724         // Note that since ratio is not infinite, we could go slightly higher than this.
 725         if (limiter_enabled) {
 726                 float threshold = pow(10.0f, limiter_threshold_dbfs / 20.0f);
 727                 float ratio = 30.0f;
 728                 float attack_time = 0.0f;  // Instant.
 729                 float release_time = 0.020f;
 730                 float makeup_gain = 1.0f;  // 0 dB.
 731                 limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 732 //              limiter_att = limiter.get_attenuation();
 733         }
 734
 735 //      printf("limiter=%+5.1f  compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
 736
 737         // Upsample 4x to find interpolated peak.
 738         peak_resampler.inp_data = samples_out.data();
 739         peak_resampler.inp_count = samples_out.size() / 2;
 740
 741         vector<float> interpolated_samples_out;
 742         interpolated_samples_out.resize(samples_out.size());
 743         while (peak_resampler.inp_count > 0) {  // About four iterations.
 744                 peak_resampler.out_data = &interpolated_samples_out[0];
 745                 peak_resampler.out_count = interpolated_samples_out.size() / 2;
 746                 peak_resampler.process();
 747                 size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
 748                 peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
 749         }
 750
 751         // Find R128 levels.
 752         vector<float> left, right;
 753         deinterleave_samples(samples_out, &left, &right);
 754         float *ptrs[] = { left.data(), right.data() };
 755         {
 756                 unique_lock<mutex> lock(r128_mutex);
 757                 r128.process(left.size(), ptrs);
 758         }
 759
 760         // Send the samples to the sound card.
 761         if (alsa) {
 762                 alsa->write(samples_out);
 763         }
 764
 765         // And finally add them to the output.
 766         h264_encoder->add_audio(frame_pts_int, move(samples_out));
 767 }
 768
 769 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 770 {
 771         GLuint vao;
 772         glGenVertexArrays(1, &vao);
 773         check_error();
 774
 775         float vertices[] = {
 776                 0.0f, 2.0f,
 777                 0.0f, 0.0f,
 778                 2.0f, 0.0f
 779         };
 780
 781         glBindVertexArray(vao);
 782         check_error();
 783
 784         // Extract Cb/Cr.
 785         GLuint fbo = resource_pool->create_fbo(dst_tex);
 786         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 787         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 788         check_error();
 789
 790         glUseProgram(cbcr_program_num);
 791         check_error();
 792
 793         glActiveTexture(GL_TEXTURE0);
 794         check_error();
 795         glBindTexture(GL_TEXTURE_2D, src_tex);
 796         check_error();
 797         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 798         check_error();
 799         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 800         check_error();
 801         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 802         check_error();
 803
 804         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 805         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 806
 807         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
 808         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
 809
 810         glDrawArrays(GL_TRIANGLES, 0, 3);
 811         check_error();
 812
 813         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
 814         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
 815
 816         glUseProgram(0);
 817         check_error();
 818
 819         resource_pool->release_fbo(fbo);
 820         glDeleteVertexArrays(1, &vao);
 821 }
 822
 823 void Mixer::release_display_frame(DisplayFrame *frame)
 824 {
 825         for (GLuint texnum : frame->temp_textures) {
 826                 resource_pool->release_2d_texture(texnum);
 827         }
 828         frame->temp_textures.clear();
 829         frame->ready_fence.reset();
 830         frame->input_frames.clear();
 831 }
 832
 833 void Mixer::start()
 834 {
 835         mixer_thread = thread(&Mixer::thread_func, this);
 836         audio_thread = thread(&Mixer::audio_thread_func, this);
 837 }
 838
 839 void Mixer::quit()
 840 {
 841         should_quit = true;
 842         mixer_thread.join();
 843         audio_thread.join();
 844 }
 845
 846 void Mixer::transition_clicked(int transition_num)
 847 {
 848         theme->transition_clicked(transition_num, pts());
 849 }
 850
 851 void Mixer::channel_clicked(int preview_num)
 852 {
 853         theme->channel_clicked(preview_num);
 854 }
 855
 856 void Mixer::reset_meters()
 857 {
 858         peak_resampler.reset();
 859         peak = 0.0f;
 860         r128.reset();
 861         r128.integr_start();
 862 }
 863
 864 Mixer::OutputChannel::~OutputChannel()
 865 {
 866         if (has_current_frame) {
 867                 parent->release_display_frame(&current_frame);
 868         }
 869         if (has_ready_frame) {
 870                 parent->release_display_frame(&ready_frame);
 871         }
 872 }
 873
 874 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
 875 {
 876         // Store this frame for display. Remove the ready frame if any
 877         // (it was seemingly never used).
 878         {
 879                 unique_lock<mutex> lock(frame_mutex);
 880                 if (has_ready_frame) {
 881                         parent->release_display_frame(&ready_frame);
 882                 }
 883                 ready_frame = frame;
 884                 has_ready_frame = true;
 885         }
 886
 887         if (has_new_frame_ready_callback) {
 888                 new_frame_ready_callback();
 889         }
 890 }
 891
 892 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
 893 {
 894         unique_lock<mutex> lock(frame_mutex);
 895         if (!has_current_frame && !has_ready_frame) {
 896                 return false;
 897         }
 898
 899         if (has_current_frame && has_ready_frame) {
 900                 // We have a new ready frame. Toss the current one.
 901                 parent->release_display_frame(&current_frame);
 902                 has_current_frame = false;
 903         }
 904         if (has_ready_frame) {
 905                 assert(!has_current_frame);
 906                 current_frame = ready_frame;
 907                 ready_frame.ready_fence.reset();  // Drop the refcount.
 908                 ready_frame.input_frames.clear();  // Drop the refcounts.
 909                 has_current_frame = true;
 910                 has_ready_frame = false;
 911         }
 912
 913         *frame = current_frame;
 914         return true;
 915 }
 916
 917 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
 918 {
 919         new_frame_ready_callback = callback;
 920         has_new_frame_ready_callback = true;
 921 }