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>
21 #include <condition_variable>
30 #include "bmusb/bmusb.h"
33 #include "h264encode.h"
34 #include "pbo_frame_allocator.h"
35 #include "ref_counted_gl_sync.h"
40 using namespace movit;
42 using namespace std::placeholders;
44 Mixer *global_mixer = nullptr;
48 void convert_fixed24_to_fp32(float *dst, size_t out_channels, const uint8_t *src, size_t in_channels, size_t num_samples)
50 for (size_t i = 0; i < num_samples; ++i) {
51 for (size_t j = 0; j < out_channels; ++j) {
55 uint32_t s = s1 | (s1 << 8) | (s2 << 16) | (s3 << 24);
56 dst[i * out_channels + j] = int(s) * (1.0f / 4294967296.0f);
58 src += 3 * (in_channels - out_channels);
64 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
65 : httpd(LOCAL_DUMP_FILE_NAME, WIDTH, HEIGHT),
67 mixer_surface(create_surface(format)),
68 h264_encoder_surface(create_surface(format)),
69 level_compressor(OUTPUT_FREQUENCY),
70 limiter(OUTPUT_FREQUENCY),
71 compressor(OUTPUT_FREQUENCY)
75 CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
78 // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
79 // will be halved when sampling them, and we need to compensate here.
80 movit_texel_subpixel_precision /= 2.0;
82 resource_pool.reset(new ResourcePool);
83 theme.reset(new Theme("theme.lua", resource_pool.get(), num_cards));
84 for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
85 output_channel[i].parent = this;
88 ImageFormat inout_format;
89 inout_format.color_space = COLORSPACE_sRGB;
90 inout_format.gamma_curve = GAMMA_sRGB;
92 // Display chain; shows the live output produced by the main chain (its RGBA version).
93 display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
95 display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT); // FIXME: GL_UNSIGNED_BYTE is really wrong.
96 display_chain->add_input(display_input);
97 display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
98 display_chain->set_dither_bits(0); // Don't bother.
99 display_chain->finalize();
101 h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
103 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
104 printf("Configuring card %d...\n", card_index);
105 CaptureCard *card = &cards[card_index];
106 card->usb = new BMUSBCapture(card_index);
107 card->usb->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
108 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT)); // 8 MB.
109 card->usb->set_video_frame_allocator(card->frame_allocator.get());
110 card->surface = create_surface(format);
111 card->usb->set_dequeue_thread_callbacks(
113 eglBindAPI(EGL_OPENGL_API);
114 card->context = create_context(card->surface);
115 if (!make_current(card->context, card->surface)) {
116 printf("failed to create bmusb context\n");
121 resource_pool->clean_context();
123 card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
124 card->usb->configure_card();
127 BMUSBCapture::start_bm_thread();
129 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
130 cards[card_index].usb->start_bm_capture();
133 //chain->enable_phase_timing(true);
135 // Set up stuff for NV12 conversion.
138 string cbcr_vert_shader = read_file("vs-cbcr.130.vert");
139 string cbcr_frag_shader =
142 "uniform sampler2D cbcr_tex; \n"
144 " gl_FragColor = texture2D(cbcr_tex, tc0); \n"
146 cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader);
148 r128.init(2, OUTPUT_FREQUENCY);
151 locut.init(FILTER_HPF, 2);
153 // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
154 // and there's a limit to how important the peak meter is.
155 peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16);
157 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
162 resource_pool->release_glsl_program(cbcr_program_num);
163 BMUSBCapture::stop_bm_thread();
165 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
167 unique_lock<mutex> lock(bmusb_mutex);
168 cards[card_index].should_quit = true; // Unblock thread.
169 cards[card_index].new_data_ready_changed.notify_all();
171 cards[card_index].usb->stop_dequeue_thread();
174 h264_encoder.reset(nullptr);
179 int unwrap_timecode(uint16_t current_wrapped, int last)
181 uint16_t last_wrapped = last & 0xffff;
182 if (current_wrapped > last_wrapped) {
183 return (last & ~0xffff) | current_wrapped;
185 return 0x10000 + ((last & ~0xffff) | current_wrapped);
189 float find_peak(const float *samples, size_t num_samples)
191 float m = fabs(samples[0]);
192 for (size_t i = 1; i < num_samples; ++i) {
193 m = std::max(m, fabs(samples[i]));
198 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
200 size_t num_samples = in.size() / 2;
201 out_l->resize(num_samples);
202 out_r->resize(num_samples);
204 const float *inptr = in.data();
205 float *lptr = &(*out_l)[0];
206 float *rptr = &(*out_r)[0];
207 for (size_t i = 0; i < num_samples; ++i) {
215 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
216 FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
217 FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
219 CaptureCard *card = &cards[card_index];
221 unsigned width, height, second_field_start, frame_rate_nom, frame_rate_den, extra_lines_top, extra_lines_bottom;
224 decode_video_format(video_format, &width, &height, &second_field_start, &extra_lines_top, &extra_lines_bottom,
225 &frame_rate_nom, &frame_rate_den, &interlaced); // Ignore return value for now.
226 int64_t frame_length = TIMEBASE * frame_rate_den / frame_rate_nom;
228 size_t num_samples = (audio_frame.len >= audio_offset) ? (audio_frame.len - audio_offset) / 8 / 3 : 0;
229 if (num_samples > OUTPUT_FREQUENCY / 10) {
230 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",
231 card_index, int(audio_frame.len), int(audio_offset),
232 timecode, int(video_frame.len), int(video_offset), video_format);
233 if (video_frame.owner) {
234 video_frame.owner->release_frame(video_frame);
236 if (audio_frame.owner) {
237 audio_frame.owner->release_frame(audio_frame);
242 int64_t local_pts = card->next_local_pts;
243 int dropped_frames = 0;
244 if (card->last_timecode != -1) {
245 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
248 // Convert the audio to stereo fp32 and add it.
250 audio.resize(num_samples * 2);
251 convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
255 unique_lock<mutex> lock(card->audio_mutex);
257 // Number of samples per frame if we need to insert silence.
258 // (Could be nonintegral, but resampling will save us then.)
259 int silence_samples = OUTPUT_FREQUENCY * frame_rate_den / frame_rate_nom;
261 if (dropped_frames > MAX_FPS * 2) {
262 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
263 card_index, card->last_timecode, timecode);
264 card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
266 } else if (dropped_frames > 0) {
267 // Insert silence as needed.
268 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
269 card_index, dropped_frames, timecode);
270 vector<float> silence;
271 silence.resize(silence_samples * 2);
272 for (int i = 0; i < dropped_frames; ++i) {
273 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), silence.data(), silence_samples);
274 // Note that if the format changed in the meantime, we have
275 // no way of detecting that; we just have to assume the frame length
276 // is always the same.
277 local_pts += frame_length;
280 if (num_samples == 0) {
281 audio.resize(silence_samples * 2);
282 num_samples = silence_samples;
284 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), audio.data(), num_samples);
285 card->next_local_pts = local_pts + frame_length;
288 card->last_timecode = timecode;
290 // Done with the audio, so release it.
291 if (audio_frame.owner) {
292 audio_frame.owner->release_frame(audio_frame);
296 // Wait until the previous frame was consumed.
297 unique_lock<mutex> lock(bmusb_mutex);
298 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
299 if (card->should_quit) return;
302 if (video_frame.len - video_offset == 0 ||
303 video_frame.len - video_offset != size_t(width * (height + extra_lines_top + extra_lines_bottom) * 2)) {
304 if (video_frame.len != 0) {
305 printf("Card %d: Dropping video frame with wrong length (%ld)\n",
306 card_index, video_frame.len - video_offset);
308 if (video_frame.owner) {
309 video_frame.owner->release_frame(video_frame);
312 // Still send on the information that we _had_ a frame, even though it's corrupted,
313 // so that pts can go up accordingly.
315 unique_lock<mutex> lock(bmusb_mutex);
316 card->new_data_ready = true;
317 card->new_frame = RefCountedFrame(FrameAllocator::Frame());
318 card->new_frame_length = frame_length;
319 card->new_frame_interlaced = false;
320 card->new_data_ready_fence = nullptr;
321 card->dropped_frames = dropped_frames;
322 card->new_data_ready_changed.notify_all();
327 PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
329 unsigned num_fields = interlaced ? 2 : 1;
330 timespec frame_upload_start;
332 // NOTE: This isn't deinterlacing. This is just sending the two fields along
333 // as separate frames without considering anything like the half-field offset.
334 // We'll need to add a proper deinterlacer on the receiving side to get this right.
335 assert(height % 2 == 0);
337 assert(frame_length % 2 == 0);
340 clock_gettime(CLOCK_MONOTONIC, &frame_upload_start);
342 RefCountedFrame new_frame(video_frame);
344 // Upload the textures.
345 size_t cbcr_width = width / 2;
346 size_t cbcr_offset = video_offset / 2;
347 size_t y_offset = video_frame.size / 2 + video_offset / 2;
349 for (unsigned field = 0; field < num_fields; ++field) {
350 unsigned field_start_line = (field == 1) ? second_field_start : extra_lines_top + field * (height + 22);
352 if (userdata->tex_y[field] == 0 ||
353 userdata->tex_cbcr[field] == 0 ||
354 width != userdata->last_width[field] ||
355 height != userdata->last_height[field]) {
356 // We changed resolution since last use of this texture, so we need to create
357 // a new object. Note that this each card has its own PBOFrameAllocator,
358 // we don't need to worry about these flip-flopping between resolutions.
359 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
361 glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
363 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
365 glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
367 userdata->last_width[field] = width;
368 userdata->last_height[field] = height;
371 GLuint pbo = userdata->pbo;
373 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
375 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, video_frame.size);
377 //glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
380 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
382 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)));
384 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
386 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(y_offset + width * field_start_line));
388 glBindTexture(GL_TEXTURE_2D, 0);
390 GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
392 assert(fence != nullptr);
395 // Don't upload the second field as fast as we can; wait until
396 // the field time has approximately passed. (Otherwise, we could
397 // get timing jitter against the other sources, and possibly also
398 // against the video display, although the latter is not as critical.)
399 // This requires our system clock to be reasonably close to the
400 // video clock, but that's not an unreasonable assumption.
401 timespec second_field_start;
402 second_field_start.tv_nsec = frame_upload_start.tv_nsec +
403 frame_length * 1000000000 / TIMEBASE;
404 second_field_start.tv_sec = frame_upload_start.tv_sec +
405 second_field_start.tv_nsec / 1000000000;
406 second_field_start.tv_nsec %= 1000000000;
408 while (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
409 &second_field_start, nullptr) == -1 &&
414 unique_lock<mutex> lock(bmusb_mutex);
415 card->new_data_ready = true;
416 card->new_frame = new_frame;
417 card->new_frame_length = frame_length;
418 card->new_frame_field = field;
419 card->new_frame_interlaced = interlaced;
420 card->new_data_ready_fence = fence;
421 card->dropped_frames = dropped_frames;
422 card->new_data_ready_changed.notify_all();
424 if (field != num_fields - 1) {
425 // Wait until the previous frame was consumed.
426 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
427 if (card->should_quit) return;
433 void Mixer::thread_func()
435 eglBindAPI(EGL_OPENGL_API);
436 QOpenGLContext *context = create_context(mixer_surface);
437 if (!make_current(context, mixer_surface)) {
442 struct timespec start, now;
443 clock_gettime(CLOCK_MONOTONIC, &start);
446 int stats_dropped_frames = 0;
448 while (!should_quit) {
449 CaptureCard card_copy[MAX_CARDS];
450 int num_samples[MAX_CARDS];
453 unique_lock<mutex> lock(bmusb_mutex);
455 // The first card is the master timer, so wait for it to have a new frame.
456 // TODO: Make configurable, and with a timeout.
457 cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
459 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
460 CaptureCard *card = &cards[card_index];
461 card_copy[card_index].usb = card->usb;
462 card_copy[card_index].new_data_ready = card->new_data_ready;
463 card_copy[card_index].new_frame = card->new_frame;
464 card_copy[card_index].new_frame_length = card->new_frame_length;
465 card_copy[card_index].new_frame_field = card->new_frame_field;
466 card_copy[card_index].new_frame_interlaced = card->new_frame_interlaced;
467 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
468 card_copy[card_index].dropped_frames = card->dropped_frames;
469 card->new_data_ready = false;
470 card->new_data_ready_changed.notify_all();
472 int num_samples_times_timebase = OUTPUT_FREQUENCY * card->new_frame_length + card->fractional_samples;
473 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
474 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
475 assert(num_samples[card_index] >= 0);
479 // Resample the audio as needed, including from previously dropped frames.
480 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
482 // Signal to the audio thread to process this frame.
483 unique_lock<mutex> lock(audio_mutex);
484 audio_task_queue.push(AudioTask{pts_int, num_samples[0]});
485 audio_task_queue_changed.notify_one();
487 if (frame_num != card_copy[0].dropped_frames) {
488 // For dropped frames, increase the pts. Note that if the format changed
489 // in the meantime, we have no way of detecting that; we just have to
490 // assume the frame length is always the same.
491 ++stats_dropped_frames;
492 pts_int += card_copy[0].new_frame_length;
496 if (audio_level_callback != nullptr) {
497 double loudness_s = r128.loudness_S();
498 double loudness_i = r128.integrated();
499 double loudness_range_low = r128.range_min();
500 double loudness_range_high = r128.range_max();
502 audio_level_callback(loudness_s, 20.0 * log10(peak),
503 loudness_i, loudness_range_low, loudness_range_high,
504 last_gain_staging_db);
507 for (unsigned card_index = 1; card_index < num_cards; ++card_index) {
508 if (card_copy[card_index].new_data_ready && card_copy[card_index].new_frame->len == 0) {
509 ++card_copy[card_index].dropped_frames;
511 if (card_copy[card_index].dropped_frames > 0) {
512 printf("Card %u dropped %d frames before this\n",
513 card_index, int(card_copy[card_index].dropped_frames));
517 // If the first card is reporting a corrupted or otherwise dropped frame,
518 // just increase the pts (skipping over this frame) and don't try to compute anything new.
519 if (card_copy[0].new_frame->len == 0) {
520 ++stats_dropped_frames;
521 pts_int += card_copy[0].new_frame_length;
525 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
526 CaptureCard *card = &card_copy[card_index];
527 if (!card->new_data_ready || card->new_frame->len == 0)
530 assert(card->new_frame != nullptr);
531 if (card->new_frame_interlaced) {
532 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) { // :-)
533 buffered_frames[card_index][frame_num] = buffered_frames[card_index][frame_num - 1];
535 buffered_frames[card_index][0] = { card->new_frame, card->new_frame_field };
537 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
538 buffered_frames[card_index][frame_num] = { card->new_frame, card->new_frame_field };
543 // The new texture might still be uploaded,
544 // tell the GPU to wait until it's there.
545 if (card->new_data_ready_fence) {
546 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
548 glDeleteSync(card->new_data_ready_fence);
553 // Get the main chain from the theme, and set its state immediately.
554 Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT);
555 EffectChain *chain = theme_main_chain.chain;
556 theme_main_chain.setup_chain();
558 GLuint y_tex, cbcr_tex;
559 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
562 // Render main chain.
563 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
564 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT); // Saves texture bandwidth, although dithering gets messed up.
565 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
567 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
568 resource_pool->release_fbo(fbo);
570 subsample_chroma(cbcr_full_tex, cbcr_tex);
571 resource_pool->release_2d_texture(cbcr_full_tex);
573 // Set the right state for rgba_tex.
574 glBindFramebuffer(GL_FRAMEBUFFER, 0);
575 glBindTexture(GL_TEXTURE_2D, rgba_tex);
576 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
577 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
578 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
580 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
583 const int64_t av_delay = TIMEBASE / 10; // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
584 h264_encoder->end_frame(fence, pts_int + av_delay, theme_main_chain.input_frames);
586 pts_int += card_copy[0].new_frame_length;
588 // The live frame just shows the RGBA texture we just rendered.
589 // It owns rgba_tex now.
590 DisplayFrame live_frame;
591 live_frame.chain = display_chain.get();
592 live_frame.setup_chain = [this, rgba_tex]{
593 display_input->set_texture_num(rgba_tex);
595 live_frame.ready_fence = fence;
596 live_frame.input_frames = {};
597 live_frame.temp_textures = { rgba_tex };
598 output_channel[OUTPUT_LIVE].output_frame(live_frame);
600 // Set up preview and any additional channels.
601 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
602 DisplayFrame display_frame;
603 Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT); // FIXME: dimensions
604 display_frame.chain = chain.chain;
605 display_frame.setup_chain = chain.setup_chain;
606 display_frame.ready_fence = fence;
607 display_frame.input_frames = chain.input_frames;
608 display_frame.temp_textures = {};
609 output_channel[i].output_frame(display_frame);
612 clock_gettime(CLOCK_MONOTONIC, &now);
613 double elapsed = now.tv_sec - start.tv_sec +
614 1e-9 * (now.tv_nsec - start.tv_nsec);
615 if (frame % 100 == 0) {
616 printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
617 frame, stats_dropped_frames, elapsed, frame / elapsed,
618 1e3 * elapsed / frame);
619 // chain->print_phase_timing();
623 // Reset every 100 frames, so that local variations in frame times
624 // (especially for the first few frames, when the shaders are
625 // compiled etc.) don't make it hard to measure for the entire
626 // remaining duration of the program.
627 if (frame == 10000) {
635 resource_pool->clean_context();
638 void Mixer::audio_thread_func()
640 while (!should_quit) {
644 unique_lock<mutex> lock(audio_mutex);
645 audio_task_queue_changed.wait(lock, [this]{ return !audio_task_queue.empty(); });
646 task = audio_task_queue.front();
647 audio_task_queue.pop();
650 process_audio_one_frame(task.pts_int, task.num_samples);
654 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples)
656 vector<float> samples_card;
657 vector<float> samples_out;
658 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
659 samples_card.resize(num_samples * 2);
661 unique_lock<mutex> lock(cards[card_index].audio_mutex);
662 if (!cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], num_samples)) {
663 printf("Card %d reported previous underrun.\n", card_index);
666 // TODO: Allow using audio from the other card(s) as well.
667 if (card_index == 0) {
668 samples_out = move(samples_card);
672 // Cut away everything under 120 Hz (or whatever the cutoff is);
673 // we don't need it for voice, and it will reduce headroom
674 // and confuse the compressor. (In particular, any hums at 50 or 60 Hz
675 // should be dampened.)
676 locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
678 // Apply a level compressor to get the general level right.
679 // Basically, if it's over about -40 dBFS, we squeeze it down to that level
680 // (or more precisely, near it, since we don't use infinite ratio),
681 // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
682 // entirely arbitrary, but from practical tests with speech, it seems to
683 // put ut around -23 LUFS, so it's a reasonable starting point for later use.
684 float ref_level_dbfs = -14.0f;
686 float threshold = 0.01f; // -40 dBFS.
688 float attack_time = 0.5f;
689 float release_time = 20.0f;
690 float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f); // +26 dB.
691 level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
692 last_gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
696 printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
697 level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
698 level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
699 20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
702 // float limiter_att, compressor_att;
704 // The real compressor.
705 if (compressor_enabled) {
706 float threshold = pow(10.0f, compressor_threshold_dbfs / 20.0f);
708 float attack_time = 0.005f;
709 float release_time = 0.040f;
710 float makeup_gain = 2.0f; // +6 dB.
711 compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
712 // compressor_att = compressor.get_attenuation();
715 // Finally a limiter at -4 dB (so, -10 dBFS) to take out the worst peaks only.
716 // Note that since ratio is not infinite, we could go slightly higher than this.
717 if (limiter_enabled) {
718 float threshold = pow(10.0f, limiter_threshold_dbfs / 20.0f);
720 float attack_time = 0.0f; // Instant.
721 float release_time = 0.020f;
722 float makeup_gain = 1.0f; // 0 dB.
723 limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
724 // limiter_att = limiter.get_attenuation();
727 // printf("limiter=%+5.1f compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
729 // Upsample 4x to find interpolated peak.
730 peak_resampler.inp_data = samples_out.data();
731 peak_resampler.inp_count = samples_out.size() / 2;
733 vector<float> interpolated_samples_out;
734 interpolated_samples_out.resize(samples_out.size());
735 while (peak_resampler.inp_count > 0) { // About four iterations.
736 peak_resampler.out_data = &interpolated_samples_out[0];
737 peak_resampler.out_count = interpolated_samples_out.size() / 2;
738 peak_resampler.process();
739 size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
740 peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
744 vector<float> left, right;
745 deinterleave_samples(samples_out, &left, &right);
746 float *ptrs[] = { left.data(), right.data() };
747 r128.process(left.size(), ptrs);
749 // Send the samples to the sound card.
751 alsa->write(samples_out);
754 // And finally add them to the output.
755 h264_encoder->add_audio(frame_pts_int, move(samples_out));
758 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
761 glGenVertexArrays(1, &vao);
770 glBindVertexArray(vao);
774 GLuint fbo = resource_pool->create_fbo(dst_tex);
775 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
776 glViewport(0, 0, WIDTH/2, HEIGHT/2);
779 glUseProgram(cbcr_program_num);
782 glActiveTexture(GL_TEXTURE0);
784 glBindTexture(GL_TEXTURE_2D, src_tex);
786 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
788 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
790 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
793 float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
794 set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
796 GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
797 GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices); // Same as vertices.
799 glDrawArrays(GL_TRIANGLES, 0, 3);
802 cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
803 cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
808 resource_pool->release_fbo(fbo);
809 glDeleteVertexArrays(1, &vao);
812 void Mixer::release_display_frame(DisplayFrame *frame)
814 for (GLuint texnum : frame->temp_textures) {
815 resource_pool->release_2d_texture(texnum);
817 frame->temp_textures.clear();
818 frame->ready_fence.reset();
819 frame->input_frames.clear();
824 mixer_thread = thread(&Mixer::thread_func, this);
825 audio_thread = thread(&Mixer::audio_thread_func, this);
835 void Mixer::transition_clicked(int transition_num)
837 theme->transition_clicked(transition_num, pts());
840 void Mixer::channel_clicked(int preview_num)
842 theme->channel_clicked(preview_num);
845 void Mixer::reset_meters()
847 peak_resampler.reset();
853 Mixer::OutputChannel::~OutputChannel()
855 if (has_current_frame) {
856 parent->release_display_frame(¤t_frame);
858 if (has_ready_frame) {
859 parent->release_display_frame(&ready_frame);
863 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
865 // Store this frame for display. Remove the ready frame if any
866 // (it was seemingly never used).
868 unique_lock<mutex> lock(frame_mutex);
869 if (has_ready_frame) {
870 parent->release_display_frame(&ready_frame);
873 has_ready_frame = true;
876 if (has_new_frame_ready_callback) {
877 new_frame_ready_callback();
881 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
883 unique_lock<mutex> lock(frame_mutex);
884 if (!has_current_frame && !has_ready_frame) {
888 if (has_current_frame && has_ready_frame) {
889 // We have a new ready frame. Toss the current one.
890 parent->release_display_frame(¤t_frame);
891 has_current_frame = false;
893 if (has_ready_frame) {
894 assert(!has_current_frame);
895 current_frame = ready_frame;
896 ready_frame.ready_fence.reset(); // Drop the refcount.
897 ready_frame.input_frames.clear(); // Drop the refcounts.
898 has_current_frame = true;
899 has_ready_frame = false;
902 *frame = current_frame;
906 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
908 new_frame_ready_callback = callback;
909 has_new_frame_ready_callback = true;