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
  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 string generate_local_dump_filename(int frame)
  78 {
  79         time_t now = time(NULL);
  80         tm now_tm;
  81         localtime_r(&now, &now_tm);
  82
  83         char timestamp[256];
  84         strftime(timestamp, sizeof(timestamp), "%F-%T%z", &now_tm);
  85
  86         // Use the frame number to disambiguate between two cuts starting
  87         // on the same second.
  88         char filename[256];
  89         snprintf(filename, sizeof(filename), "%s%s-f%02d%s",
  90                 LOCAL_DUMP_PREFIX, timestamp, frame % 100, LOCAL_DUMP_SUFFIX);
  91         return filename;
  92 }
  93
  94 }  // namespace
  95
  96 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
  97         : httpd(WIDTH, HEIGHT),
  98           num_cards(num_cards),
  99           mixer_surface(create_surface(format)),
 100           h264_encoder_surface(create_surface(format)),
 101           correlation(OUTPUT_FREQUENCY),
 102           level_compressor(OUTPUT_FREQUENCY),
 103           limiter(OUTPUT_FREQUENCY),
 104           compressor(OUTPUT_FREQUENCY)
 105 {
 106         httpd.open_output_file(generate_local_dump_filename(/*frame=*/0).c_str());
 107         httpd.start(9095);
 108
 109         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 110         check_error();
 111
 112         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 113         // will be halved when sampling them, and we need to compensate here.
 114         movit_texel_subpixel_precision /= 2.0;
 115
 116         resource_pool.reset(new ResourcePool);
 117         theme.reset(new Theme("theme.lua", resource_pool.get(), num_cards));
 118         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 119                 output_channel[i].parent = this;
 120         }
 121
 122         ImageFormat inout_format;
 123         inout_format.color_space = COLORSPACE_sRGB;
 124         inout_format.gamma_curve = GAMMA_sRGB;
 125
 126         // Display chain; shows the live output produced by the main chain (its RGBA version).
 127         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 128         check_error();
 129         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 130         display_chain->add_input(display_input);
 131         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 132         display_chain->set_dither_bits(0);  // Don't bother.
 133         display_chain->finalize();
 134
 135         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
 136
 137         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 138                 printf("Configuring card %d...\n", card_index);
 139                 CaptureCard *card = &cards[card_index];
 140                 card->usb = new BMUSBCapture(card_index);
 141                 card->usb->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 142                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
 143                 card->usb->set_video_frame_allocator(card->frame_allocator.get());
 144                 card->surface = create_surface(format);
 145                 card->usb->set_dequeue_thread_callbacks(
 146                         [card]{
 147                                 eglBindAPI(EGL_OPENGL_API);
 148                                 card->context = create_context(card->surface);
 149                                 if (!make_current(card->context, card->surface)) {
 150                                         printf("failed to create bmusb context\n");
 151                                         exit(1);
 152                                 }
 153                         },
 154                         [this]{
 155                                 resource_pool->clean_context();
 156                         });
 157                 card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
 158                 card->usb->configure_card();
 159         }
 160
 161         BMUSBCapture::start_bm_thread();
 162
 163         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 164                 cards[card_index].usb->start_bm_capture();
 165         }
 166
 167         // Set up stuff for NV12 conversion.
 168
 169         // Cb/Cr shader.
 170         string cbcr_vert_shader =
 171                 "#version 130 \n"
 172                 " \n"
 173                 "in vec2 position; \n"
 174                 "in vec2 texcoord; \n"
 175                 "out vec2 tc0; \n"
 176                 "uniform vec2 foo_chroma_offset_0; \n"
 177                 " \n"
 178                 "void main() \n"
 179                 "{ \n"
 180                 "    // The result of glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0) is: \n"
 181                 "    // \n"
 182                 "    //   2.000  0.000  0.000 -1.000 \n"
 183                 "    //   0.000  2.000  0.000 -1.000 \n"
 184                 "    //   0.000  0.000 -2.000 -1.000 \n"
 185                 "    //   0.000  0.000  0.000  1.000 \n"
 186                 "    gl_Position = vec4(2.0 * position.x - 1.0, 2.0 * position.y - 1.0, -1.0, 1.0); \n"
 187                 "    vec2 flipped_tc = texcoord; \n"
 188                 "    tc0 = flipped_tc + foo_chroma_offset_0; \n"
 189                 "} \n";
 190         string cbcr_frag_shader =
 191                 "#version 130 \n"
 192                 "in vec2 tc0; \n"
 193                 "uniform sampler2D cbcr_tex; \n"
 194                 "out vec4 FragColor; \n"
 195                 "void main() { \n"
 196                 "    FragColor = texture(cbcr_tex, tc0); \n"
 197                 "} \n";
 198         vector<string> frag_shader_outputs;
 199         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
 200
 201         r128.init(2, OUTPUT_FREQUENCY);
 202         r128.integr_start();
 203
 204         locut.init(FILTER_HPF, 2);
 205
 206         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
 207         // and there's a limit to how important the peak meter is.
 208         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16, /*frel=*/1.0);
 209
 210         alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 211 }
 212
 213 Mixer::~Mixer()
 214 {
 215         resource_pool->release_glsl_program(cbcr_program_num);
 216         BMUSBCapture::stop_bm_thread();
 217
 218         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 219                 {
 220                         unique_lock<mutex> lock(bmusb_mutex);
 221                         cards[card_index].should_quit = true;  // Unblock thread.
 222                         cards[card_index].new_data_ready_changed.notify_all();
 223                 }
 224                 cards[card_index].usb->stop_dequeue_thread();
 225         }
 226
 227         h264_encoder.reset(nullptr);
 228 }
 229
 230 namespace {
 231
 232 int unwrap_timecode(uint16_t current_wrapped, int last)
 233 {
 234         uint16_t last_wrapped = last & 0xffff;
 235         if (current_wrapped > last_wrapped) {
 236                 return (last & ~0xffff) | current_wrapped;
 237         } else {
 238                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 239         }
 240 }
 241
 242 float find_peak(const float *samples, size_t num_samples)
 243 {
 244         float m = fabs(samples[0]);
 245         for (size_t i = 1; i < num_samples; ++i) {
 246                 m = max(m, fabs(samples[i]));
 247         }
 248         return m;
 249 }
 250
 251 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 252 {
 253         size_t num_samples = in.size() / 2;
 254         out_l->resize(num_samples);
 255         out_r->resize(num_samples);
 256
 257         const float *inptr = in.data();
 258         float *lptr = &(*out_l)[0];
 259         float *rptr = &(*out_r)[0];
 260         for (size_t i = 0; i < num_samples; ++i) {
 261                 *lptr++ = *inptr++;
 262                 *rptr++ = *inptr++;
 263         }
 264 }
 265
 266 }  // namespace
 267
 268 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 269                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 270                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
 271 {
 272         CaptureCard *card = &cards[card_index];
 273
 274         unsigned width, height, second_field_start, frame_rate_nom, frame_rate_den, extra_lines_top, extra_lines_bottom;
 275         bool interlaced;
 276
 277         decode_video_format(video_format, &width, &height, &second_field_start, &extra_lines_top, &extra_lines_bottom,
 278                             &frame_rate_nom, &frame_rate_den, &interlaced);  // Ignore return value for now.
 279         int64_t frame_length = int64_t(TIMEBASE * frame_rate_den) / frame_rate_nom;
 280
 281         size_t num_samples = (audio_frame.len >= audio_offset) ? (audio_frame.len - audio_offset) / 8 / 3 : 0;
 282         if (num_samples > OUTPUT_FREQUENCY / 10) {
 283                 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",
 284                         card_index, int(audio_frame.len), int(audio_offset),
 285                         timecode, int(video_frame.len), int(video_offset), video_format);
 286                 if (video_frame.owner) {
 287                         video_frame.owner->release_frame(video_frame);
 288                 }
 289                 if (audio_frame.owner) {
 290                         audio_frame.owner->release_frame(audio_frame);
 291                 }
 292                 return;
 293         }
 294
 295         int64_t local_pts = card->next_local_pts;
 296         int dropped_frames = 0;
 297         if (card->last_timecode != -1) {
 298                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 299         }
 300
 301         // Convert the audio to stereo fp32 and add it.
 302         vector<float> audio;
 303         audio.resize(num_samples * 2);
 304         convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
 305
 306         // Add the audio.
 307         {
 308                 unique_lock<mutex> lock(card->audio_mutex);
 309
 310                 // Number of samples per frame if we need to insert silence.
 311                 // (Could be nonintegral, but resampling will save us then.)
 312                 int silence_samples = OUTPUT_FREQUENCY * frame_rate_den / frame_rate_nom;
 313
 314                 if (dropped_frames > MAX_FPS * 2) {
 315                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 316                                 card_index, card->last_timecode, timecode);
 317                         card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
 318                         dropped_frames = 0;
 319                 } else if (dropped_frames > 0) {
 320                         // Insert silence as needed.
 321                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 322                                 card_index, dropped_frames, timecode);
 323                         vector<float> silence(silence_samples * 2, 0.0f);
 324                         for (int i = 0; i < dropped_frames; ++i) {
 325                                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), silence.data(), silence_samples);
 326                                 // Note that if the format changed in the meantime, we have
 327                                 // no way of detecting that; we just have to assume the frame length
 328                                 // is always the same.
 329                                 local_pts += frame_length;
 330                         }
 331                 }
 332                 if (num_samples == 0) {
 333                         audio.resize(silence_samples * 2);
 334                         num_samples = silence_samples;
 335                 }
 336                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), audio.data(), num_samples);
 337                 card->next_local_pts = local_pts + frame_length;
 338         }
 339
 340         card->last_timecode = timecode;
 341
 342         // Done with the audio, so release it.
 343         if (audio_frame.owner) {
 344                 audio_frame.owner->release_frame(audio_frame);
 345         }
 346
 347         {
 348                 // Wait until the previous frame was consumed.
 349                 unique_lock<mutex> lock(bmusb_mutex);
 350                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
 351                 if (card->should_quit) return;
 352         }
 353
 354         size_t expected_length = width * (height + extra_lines_top + extra_lines_bottom) * 2;
 355         if (video_frame.len - video_offset == 0 ||
 356             video_frame.len - video_offset != expected_length) {
 357                 if (video_frame.len != 0) {
 358                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 359                                 card_index, video_frame.len - video_offset, expected_length);
 360                 }
 361                 if (video_frame.owner) {
 362                         video_frame.owner->release_frame(video_frame);
 363                 }
 364
 365                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 366                 // so that pts can go up accordingly.
 367                 {
 368                         unique_lock<mutex> lock(bmusb_mutex);
 369                         card->new_data_ready = true;
 370                         card->new_frame = RefCountedFrame(FrameAllocator::Frame());
 371                         card->new_frame_length = frame_length;
 372                         card->new_frame_interlaced = false;
 373                         card->new_data_ready_fence = nullptr;
 374                         card->dropped_frames = dropped_frames;
 375                         card->new_data_ready_changed.notify_all();
 376                 }
 377                 return;
 378         }
 379
 380         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 381
 382         unsigned num_fields = interlaced ? 2 : 1;
 383         timespec frame_upload_start;
 384         if (interlaced) {
 385                 // Send the two fields along as separate frames; the other side will need to add
 386                 // a deinterlacer to actually get this right.
 387                 assert(height % 2 == 0);
 388                 height /= 2;
 389                 assert(frame_length % 2 == 0);
 390                 frame_length /= 2;
 391                 num_fields = 2;
 392                 clock_gettime(CLOCK_MONOTONIC, &frame_upload_start);
 393         }
 394         userdata->last_interlaced = interlaced;
 395         userdata->last_frame_rate_nom = frame_rate_nom;
 396         userdata->last_frame_rate_den = frame_rate_den;
 397         RefCountedFrame new_frame(video_frame);
 398
 399         // Upload the textures.
 400         size_t cbcr_width = width / 2;
 401         size_t cbcr_offset = video_offset / 2;
 402         size_t y_offset = video_frame.size / 2 + video_offset / 2;
 403
 404         for (unsigned field = 0; field < num_fields; ++field) {
 405                 unsigned field_start_line = (field == 1) ? second_field_start : extra_lines_top + field * (height + 22);
 406
 407                 if (userdata->tex_y[field] == 0 ||
 408                     userdata->tex_cbcr[field] == 0 ||
 409                     width != userdata->last_width[field] ||
 410                     height != userdata->last_height[field]) {
 411                         // We changed resolution since last use of this texture, so we need to create
 412                         // a new object. Note that this each card has its own PBOFrameAllocator,
 413                         // we don't need to worry about these flip-flopping between resolutions.
 414                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 415                         check_error();
 416                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 417                         check_error();
 418                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 419                         check_error();
 420                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 421                         check_error();
 422                         userdata->last_width[field] = width;
 423                         userdata->last_height[field] = height;
 424                 }
 425
 426                 GLuint pbo = userdata->pbo;
 427                 check_error();
 428                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
 429                 check_error();
 430                 glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 431                 check_error();
 432
 433                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 434                 check_error();
 435                 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)));
 436                 check_error();
 437                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 438                 check_error();
 439                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(y_offset + width * field_start_line));
 440                 check_error();
 441                 glBindTexture(GL_TEXTURE_2D, 0);
 442                 check_error();
 443                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
 444                 check_error();
 445                 GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 446                 check_error();
 447                 assert(fence != nullptr);
 448
 449                 if (field == 1) {
 450                         // Don't upload the second field as fast as we can; wait until
 451                         // the field time has approximately passed. (Otherwise, we could
 452                         // get timing jitter against the other sources, and possibly also
 453                         // against the video display, although the latter is not as critical.)
 454                         // This requires our system clock to be reasonably close to the
 455                         // video clock, but that's not an unreasonable assumption.
 456                         timespec second_field_start;
 457                         second_field_start.tv_nsec = frame_upload_start.tv_nsec +
 458                                 frame_length * 1000000000 / TIMEBASE;
 459                         second_field_start.tv_sec = frame_upload_start.tv_sec +
 460                                 second_field_start.tv_nsec / 1000000000;
 461                         second_field_start.tv_nsec %= 1000000000;
 462
 463                         while (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
 464                                                &second_field_start, nullptr) == -1 &&
 465                                errno == EINTR) ;
 466                 }
 467
 468                 {
 469                         unique_lock<mutex> lock(bmusb_mutex);
 470                         card->new_data_ready = true;
 471                         card->new_frame = new_frame;
 472                         card->new_frame_length = frame_length;
 473                         card->new_frame_field = field;
 474                         card->new_frame_interlaced = interlaced;
 475                         card->new_data_ready_fence = fence;
 476                         card->dropped_frames = dropped_frames;
 477                         card->new_data_ready_changed.notify_all();
 478
 479                         if (field != num_fields - 1) {
 480                                 // Wait until the previous frame was consumed.
 481                                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
 482                                 if (card->should_quit) return;
 483                         }
 484                 }
 485         }
 486 }
 487
 488 void Mixer::thread_func()
 489 {
 490         eglBindAPI(EGL_OPENGL_API);
 491         QOpenGLContext *context = create_context(mixer_surface);
 492         if (!make_current(context, mixer_surface)) {
 493                 printf("oops\n");
 494                 exit(1);
 495         }
 496
 497         struct timespec start, now;
 498         clock_gettime(CLOCK_MONOTONIC, &start);
 499
 500         int frame = 0;
 501         int stats_dropped_frames = 0;
 502
 503         while (!should_quit) {
 504                 CaptureCard card_copy[MAX_CARDS];
 505                 int num_samples[MAX_CARDS];
 506
 507                 {
 508                         unique_lock<mutex> lock(bmusb_mutex);
 509
 510                         // The first card is the master timer, so wait for it to have a new frame.
 511                         // TODO: Make configurable, and with a timeout.
 512                         cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
 513
 514                         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 515                                 CaptureCard *card = &cards[card_index];
 516                                 card_copy[card_index].usb = card->usb;
 517                                 card_copy[card_index].new_data_ready = card->new_data_ready;
 518                                 card_copy[card_index].new_frame = card->new_frame;
 519                                 card_copy[card_index].new_frame_length = card->new_frame_length;
 520                                 card_copy[card_index].new_frame_field = card->new_frame_field;
 521                                 card_copy[card_index].new_frame_interlaced = card->new_frame_interlaced;
 522                                 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
 523                                 card_copy[card_index].dropped_frames = card->dropped_frames;
 524                                 card->new_data_ready = false;
 525                                 card->new_data_ready_changed.notify_all();
 526
 527                                 int num_samples_times_timebase = OUTPUT_FREQUENCY * card->new_frame_length + card->fractional_samples;
 528                                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
 529                                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
 530                                 assert(num_samples[card_index] >= 0);
 531                         }
 532                 }
 533
 534                 // Resample the audio as needed, including from previously dropped frames.
 535                 assert(num_cards > 0);
 536                 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
 537                         {
 538                                 // Signal to the audio thread to process this frame.
 539                                 unique_lock<mutex> lock(audio_mutex);
 540                                 audio_task_queue.push(AudioTask{pts_int, num_samples[0]});
 541                                 audio_task_queue_changed.notify_one();
 542                         }
 543                         if (frame_num != card_copy[0].dropped_frames) {
 544                                 // For dropped frames, increase the pts. Note that if the format changed
 545                                 // in the meantime, we have no way of detecting that; we just have to
 546                                 // assume the frame length is always the same.
 547                                 ++stats_dropped_frames;
 548                                 pts_int += card_copy[0].new_frame_length;
 549                         }
 550                 }
 551
 552                 if (audio_level_callback != nullptr) {
 553                         unique_lock<mutex> lock(compressor_mutex);
 554                         double loudness_s = r128.loudness_S();
 555                         double loudness_i = r128.integrated();
 556                         double loudness_range_low = r128.range_min();
 557                         double loudness_range_high = r128.range_max();
 558
 559                         audio_level_callback(loudness_s, 20.0 * log10(peak),
 560                                              loudness_i, loudness_range_low, loudness_range_high,
 561                                              gain_staging_db, 20.0 * log10(final_makeup_gain),
 562                                              correlation.get_correlation());
 563                 }
 564
 565                 for (unsigned card_index = 1; card_index < num_cards; ++card_index) {
 566                         if (card_copy[card_index].new_data_ready && card_copy[card_index].new_frame->len == 0) {
 567                                 ++card_copy[card_index].dropped_frames;
 568                         }
 569                         if (card_copy[card_index].dropped_frames > 0) {
 570                                 printf("Card %u dropped %d frames before this\n",
 571                                         card_index, int(card_copy[card_index].dropped_frames));
 572                         }
 573                 }
 574
 575                 // If the first card is reporting a corrupted or otherwise dropped frame,
 576                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 577                 if (card_copy[0].new_frame->len == 0) {
 578                         ++stats_dropped_frames;
 579                         pts_int += card_copy[0].new_frame_length;
 580                         continue;
 581                 }
 582
 583                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 584                         CaptureCard *card = &card_copy[card_index];
 585                         if (!card->new_data_ready || card->new_frame->len == 0)
 586                                 continue;
 587
 588                         assert(card->new_frame != nullptr);
 589                         insert_new_frame(card->new_frame, card->new_frame_field, card->new_frame_interlaced, card_index, &input_state);
 590                         check_error();
 591
 592                         // The new texture might still be uploaded,
 593                         // tell the GPU to wait until it's there.
 594                         if (card->new_data_ready_fence) {
 595                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
 596                                 check_error();
 597                                 glDeleteSync(card->new_data_ready_fence);
 598                                 check_error();
 599                         }
 600                 }
 601
 602                 // Get the main chain from the theme, and set its state immediately.
 603                 Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
 604                 EffectChain *chain = theme_main_chain.chain;
 605                 theme_main_chain.setup_chain();
 606                 //theme_main_chain.chain->enable_phase_timing(true);
 607
 608                 GLuint y_tex, cbcr_tex;
 609                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
 610                 assert(got_frame);
 611
 612                 // Render main chain.
 613                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 614                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 615                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 616                 check_error();
 617                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 618                 resource_pool->release_fbo(fbo);
 619
 620                 subsample_chroma(cbcr_full_tex, cbcr_tex);
 621                 resource_pool->release_2d_texture(cbcr_full_tex);
 622
 623                 // Set the right state for rgba_tex.
 624                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
 625                 glBindTexture(GL_TEXTURE_2D, rgba_tex);
 626                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 627                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 628                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 629
 630                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 631                 check_error();
 632
 633                 const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
 634                 h264_encoder->end_frame(fence, pts_int + av_delay, theme_main_chain.input_frames);
 635                 ++frame;
 636                 pts_int += card_copy[0].new_frame_length;
 637
 638                 // The live frame just shows the RGBA texture we just rendered.
 639                 // It owns rgba_tex now.
 640                 DisplayFrame live_frame;
 641                 live_frame.chain = display_chain.get();
 642                 live_frame.setup_chain = [this, rgba_tex]{
 643                         display_input->set_texture_num(rgba_tex);
 644                 };
 645                 live_frame.ready_fence = fence;
 646                 live_frame.input_frames = {};
 647                 live_frame.temp_textures = { rgba_tex };
 648                 output_channel[OUTPUT_LIVE].output_frame(live_frame);
 649
 650                 // Set up preview and any additional channels.
 651                 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 652                         DisplayFrame display_frame;
 653                         Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
 654                         display_frame.chain = chain.chain;
 655                         display_frame.setup_chain = chain.setup_chain;
 656                         display_frame.ready_fence = fence;
 657                         display_frame.input_frames = chain.input_frames;
 658                         display_frame.temp_textures = {};
 659                         output_channel[i].output_frame(display_frame);
 660                 }
 661
 662                 clock_gettime(CLOCK_MONOTONIC, &now);
 663                 double elapsed = now.tv_sec - start.tv_sec +
 664                         1e-9 * (now.tv_nsec - start.tv_nsec);
 665                 if (frame % 100 == 0) {
 666                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
 667                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
 668                                 1e3 * elapsed / frame);
 669                 //      chain->print_phase_timing();
 670                 }
 671
 672                 if (should_cut.exchange(false)) {  // Test and clear.
 673                         string filename = generate_local_dump_filename(frame);
 674                         printf("Starting new recording: %s\n", filename.c_str());
 675                         h264_encoder->shutdown();
 676                         httpd.close_output_file();
 677                         httpd.open_output_file(filename.c_str());
 678                         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
 679                 }
 680
 681 #if 0
 682                 // Reset every 100 frames, so that local variations in frame times
 683                 // (especially for the first few frames, when the shaders are
 684                 // compiled etc.) don't make it hard to measure for the entire
 685                 // remaining duration of the program.
 686                 if (frame == 10000) {
 687                         frame = 0;
 688                         start = now;
 689                 }
 690 #endif
 691                 check_error();
 692         }
 693
 694         resource_pool->clean_context();
 695 }
 696
 697 void Mixer::audio_thread_func()
 698 {
 699         while (!should_quit) {
 700                 AudioTask task;
 701
 702                 {
 703                         unique_lock<mutex> lock(audio_mutex);
 704                         audio_task_queue_changed.wait(lock, [this]{ return !audio_task_queue.empty(); });
 705                         task = audio_task_queue.front();
 706                         audio_task_queue.pop();
 707                 }
 708
 709                 process_audio_one_frame(task.pts_int, task.num_samples);
 710         }
 711 }
 712
 713 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples)
 714 {
 715         vector<float> samples_card;
 716         vector<float> samples_out;
 717
 718         // TODO: Allow mixing audio from several sources.
 719         unsigned selected_audio_card = theme->map_signal(audio_source_channel);
 720         assert(selected_audio_card < num_cards);
 721
 722         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 723                 samples_card.resize(num_samples * 2);
 724                 {
 725                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
 726                         if (!cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], num_samples)) {
 727                                 printf("Card %d reported previous underrun.\n", card_index);
 728                         }
 729                 }
 730                 if (card_index == selected_audio_card) {
 731                         samples_out = move(samples_card);
 732                 }
 733         }
 734
 735         // Cut away everything under 120 Hz (or whatever the cutoff is);
 736         // we don't need it for voice, and it will reduce headroom
 737         // and confuse the compressor. (In particular, any hums at 50 or 60 Hz
 738         // should be dampened.)
 739         if (locut_enabled) {
 740                 locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
 741         }
 742
 743         // Apply a level compressor to get the general level right.
 744         // Basically, if it's over about -40 dBFS, we squeeze it down to that level
 745         // (or more precisely, near it, since we don't use infinite ratio),
 746         // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
 747         // entirely arbitrary, but from practical tests with speech, it seems to
 748         // put ut around -23 LUFS, so it's a reasonable starting point for later use.
 749         {
 750                 unique_lock<mutex> lock(compressor_mutex);
 751                 if (level_compressor_enabled) {
 752                         float threshold = 0.01f;   // -40 dBFS.
 753                         float ratio = 20.0f;
 754                         float attack_time = 0.5f;
 755                         float release_time = 20.0f;
 756                         float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f);  // +26 dB.
 757                         level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 758                         gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
 759                 } else {
 760                         // Just apply the gain we already had.
 761                         float g = pow(10.0f, gain_staging_db / 20.0f);
 762                         for (size_t i = 0; i < samples_out.size(); ++i) {
 763                                 samples_out[i] *= g;
 764                         }
 765                 }
 766         }
 767
 768 #if 0
 769         printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
 770                 level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
 771                 level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
 772                 20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
 773 #endif
 774
 775 //      float limiter_att, compressor_att;
 776
 777         // The real compressor.
 778         if (compressor_enabled) {
 779                 float threshold = pow(10.0f, compressor_threshold_dbfs / 20.0f);
 780                 float ratio = 20.0f;
 781                 float attack_time = 0.005f;
 782                 float release_time = 0.040f;
 783                 float makeup_gain = 2.0f;  // +6 dB.
 784                 compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 785 //              compressor_att = compressor.get_attenuation();
 786         }
 787
 788         // Finally a limiter at -4 dB (so, -10 dBFS) to take out the worst peaks only.
 789         // Note that since ratio is not infinite, we could go slightly higher than this.
 790         if (limiter_enabled) {
 791                 float threshold = pow(10.0f, limiter_threshold_dbfs / 20.0f);
 792                 float ratio = 30.0f;
 793                 float attack_time = 0.0f;  // Instant.
 794                 float release_time = 0.020f;
 795                 float makeup_gain = 1.0f;  // 0 dB.
 796                 limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
 797 //              limiter_att = limiter.get_attenuation();
 798         }
 799
 800 //      printf("limiter=%+5.1f  compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
 801
 802         // Upsample 4x to find interpolated peak.
 803         peak_resampler.inp_data = samples_out.data();
 804         peak_resampler.inp_count = samples_out.size() / 2;
 805
 806         vector<float> interpolated_samples_out;
 807         interpolated_samples_out.resize(samples_out.size());
 808         while (peak_resampler.inp_count > 0) {  // About four iterations.
 809                 peak_resampler.out_data = &interpolated_samples_out[0];
 810                 peak_resampler.out_count = interpolated_samples_out.size() / 2;
 811                 peak_resampler.process();
 812                 size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
 813                 peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
 814                 peak_resampler.out_data = nullptr;
 815         }
 816
 817         // At this point, we are most likely close to +0 LU, but all of our
 818         // measurements have been on raw sample values, not R128 values.
 819         // So we have a final makeup gain to get us to +0 LU; the gain
 820         // adjustments required should be relatively small, and also, the
 821         // offset shouldn't change much (only if the type of audio changes
 822         // significantly). Thus, we shoot for updating this value basically
 823         // “whenever we process buffers”, since the R128 calculation isn't exactly
 824         // something we get out per-sample.
 825         //
 826         // Note that there's a feedback loop here, so we choose a very slow filter
 827         // (half-time of 100 seconds).
 828         double target_loudness_factor, alpha;
 829         {
 830                 unique_lock<mutex> lock(compressor_mutex);
 831                 double loudness_lu = r128.loudness_M() - ref_level_lufs;
 832                 double current_makeup_lu = 20.0f * log10(final_makeup_gain);
 833                 target_loudness_factor = pow(10.0f, -loudness_lu / 20.0f);
 834
 835                 // If we're outside +/- 5 LU uncorrected, we don't count it as
 836                 // a normal signal (probably silence) and don't change the
 837                 // correction factor; just apply what we already have.
 838                 if (fabs(loudness_lu - current_makeup_lu) >= 5.0 || !final_makeup_gain_auto) {
 839                         alpha = 0.0;
 840                 } else {
 841                         // Formula adapted from
 842                         // https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter.
 843                         const double half_time_s = 100.0;
 844                         const double fc_mul_2pi_delta_t = 1.0 / (half_time_s * OUTPUT_FREQUENCY);
 845                         alpha = fc_mul_2pi_delta_t / (fc_mul_2pi_delta_t + 1.0);
 846                 }
 847
 848                 double m = final_makeup_gain;
 849                 for (size_t i = 0; i < samples_out.size(); i += 2) {
 850                         samples_out[i + 0] *= m;
 851                         samples_out[i + 1] *= m;
 852                         m += (target_loudness_factor - m) * alpha;
 853                 }
 854                 final_makeup_gain = m;
 855         }
 856
 857         // Find R128 levels and L/R correlation.
 858         vector<float> left, right;
 859         deinterleave_samples(samples_out, &left, &right);
 860         float *ptrs[] = { left.data(), right.data() };
 861         {
 862                 unique_lock<mutex> lock(compressor_mutex);
 863                 r128.process(left.size(), ptrs);
 864                 correlation.process_samples(samples_out);
 865         }
 866
 867         // Send the samples to the sound card.
 868         if (alsa) {
 869                 alsa->write(samples_out);
 870         }
 871
 872         // And finally add them to the output.
 873         h264_encoder->add_audio(frame_pts_int, move(samples_out));
 874 }
 875
 876 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 877 {
 878         GLuint vao;
 879         glGenVertexArrays(1, &vao);
 880         check_error();
 881
 882         float vertices[] = {
 883                 0.0f, 2.0f,
 884                 0.0f, 0.0f,
 885                 2.0f, 0.0f
 886         };
 887
 888         glBindVertexArray(vao);
 889         check_error();
 890
 891         // Extract Cb/Cr.
 892         GLuint fbo = resource_pool->create_fbo(dst_tex);
 893         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 894         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 895         check_error();
 896
 897         glUseProgram(cbcr_program_num);
 898         check_error();
 899
 900         glActiveTexture(GL_TEXTURE0);
 901         check_error();
 902         glBindTexture(GL_TEXTURE_2D, src_tex);
 903         check_error();
 904         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 905         check_error();
 906         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 907         check_error();
 908         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 909         check_error();
 910
 911         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 912         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 913
 914         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
 915         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
 916
 917         glDrawArrays(GL_TRIANGLES, 0, 3);
 918         check_error();
 919
 920         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
 921         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
 922
 923         glUseProgram(0);
 924         check_error();
 925
 926         resource_pool->release_fbo(fbo);
 927         glDeleteVertexArrays(1, &vao);
 928 }
 929
 930 void Mixer::release_display_frame(DisplayFrame *frame)
 931 {
 932         for (GLuint texnum : frame->temp_textures) {
 933                 resource_pool->release_2d_texture(texnum);
 934         }
 935         frame->temp_textures.clear();
 936         frame->ready_fence.reset();
 937         frame->input_frames.clear();
 938 }
 939
 940 void Mixer::start()
 941 {
 942         mixer_thread = thread(&Mixer::thread_func, this);
 943         audio_thread = thread(&Mixer::audio_thread_func, this);
 944 }
 945
 946 void Mixer::quit()
 947 {
 948         should_quit = true;
 949         mixer_thread.join();
 950         audio_thread.join();
 951 }
 952
 953 void Mixer::transition_clicked(int transition_num)
 954 {
 955         theme->transition_clicked(transition_num, pts());
 956 }
 957
 958 void Mixer::channel_clicked(int preview_num)
 959 {
 960         theme->channel_clicked(preview_num);
 961 }
 962
 963 void Mixer::reset_meters()
 964 {
 965         peak_resampler.reset();
 966         peak = 0.0f;
 967         r128.reset();
 968         r128.integr_start();
 969         correlation.reset();
 970 }
 971
 972 Mixer::OutputChannel::~OutputChannel()
 973 {
 974         if (has_current_frame) {
 975                 parent->release_display_frame(&current_frame);
 976         }
 977         if (has_ready_frame) {
 978                 parent->release_display_frame(&ready_frame);
 979         }
 980 }
 981
 982 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
 983 {
 984         // Store this frame for display. Remove the ready frame if any
 985         // (it was seemingly never used).
 986         {
 987                 unique_lock<mutex> lock(frame_mutex);
 988                 if (has_ready_frame) {
 989                         parent->release_display_frame(&ready_frame);
 990                 }
 991                 ready_frame = frame;
 992                 has_ready_frame = true;
 993         }
 994
 995         if (has_new_frame_ready_callback) {
 996                 new_frame_ready_callback();
 997         }
 998 }
 999
1000 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1001 {
1002         unique_lock<mutex> lock(frame_mutex);
1003         if (!has_current_frame && !has_ready_frame) {
1004                 return false;
1005         }
1006
1007         if (has_current_frame && has_ready_frame) {
1008                 // We have a new ready frame. Toss the current one.
1009                 parent->release_display_frame(&current_frame);
1010                 has_current_frame = false;
1011         }
1012         if (has_ready_frame) {
1013                 assert(!has_current_frame);
1014                 current_frame = ready_frame;
1015                 ready_frame.ready_fence.reset();  // Drop the refcount.
1016                 ready_frame.input_frames.clear();  // Drop the refcounts.
1017                 has_current_frame = true;
1018                 has_ready_frame = false;
1019         }
1020
1021         *frame = current_frame;
1022         return true;
1023 }
1024
1025 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1026 {
1027         new_frame_ready_callback = callback;
1028         has_new_frame_ready_callback = true;
1029 }