+ // Check for cards that have been disconnected since last frame.
+ for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
+ CaptureCard *card = &cards[card_index];
+ if (card->capture->get_disconnected()) {
+ fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
+ FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
+ configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
+ card->queue_length_policy.reset(card_index);
+ card->capture->start_bm_capture();
+ }
+ }
+
+ // Check for cards that have been connected since last frame.
+ vector<libusb_device *> hotplugged_cards_copy;
+ {
+ lock_guard<mutex> lock(hotplug_mutex);
+ swap(hotplugged_cards, hotplugged_cards_copy);
+ }
+ for (libusb_device *new_dev : hotplugged_cards_copy) {
+ // Look for a fake capture card where we can stick this in.
+ int free_card_index = -1;
+ for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
+ if (cards[card_index].is_fake_capture) {
+ free_card_index = card_index;
+ break;
+ }
+ }
+
+ if (free_card_index == -1) {
+ fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
+ libusb_unref_device(new_dev);
+ } else {
+ // BMUSBCapture takes ownership.
+ fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
+ CaptureCard *card = &cards[free_card_index];
+ BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
+ configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
+ card->queue_length_policy.reset(free_card_index);
+ capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
+ capture->start_bm_capture();
+ }
+ }
+}
+
+
+void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame, bool is_preroll, steady_clock::time_point frame_timestamp)
+{
+ // Resample the audio as needed, including from previously dropped frames.
+ assert(num_cards > 0);
+ for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
+ const bool dropped_frame = (frame_num != dropped_frames);
+ {
+ // Signal to the audio thread to process this frame.
+ // Note that if the frame is a dropped frame, we signal that
+ // we don't want to use this frame as base for adjusting
+ // the resampler rate. The reason for this is that the timing
+ // of these frames is often way too late; they typically don't
+ // “arrive” before we synthesize them. Thus, we could end up
+ // in a situation where we have inserted e.g. five audio frames
+ // into the queue before we then start pulling five of them
+ // back out. This makes ResamplingQueue overestimate the delay,
+ // causing undue resampler changes. (We _do_ use the last,
+ // non-dropped frame; perhaps we should just discard that as well,
+ // since dropped frames are expected to be rare, and it might be
+ // better to just wait until we have a slightly more normal situation).
+ unique_lock<mutex> lock(audio_mutex);
+ bool adjust_rate = !dropped_frame && !is_preroll;
+ audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
+ audio_task_queue_changed.notify_one();
+ }
+ if (dropped_frame) {
+ // For dropped frames, increase the pts. Note that if the format changed
+ // in the meantime, we have no way of detecting that; we just have to
+ // assume the frame length is always the same.
+ pts_int += length_per_frame;
+ }
+ }
+}
+
+void Mixer::render_one_frame(int64_t duration)
+{
+ // Determine the time code for this frame before we start rendering.
+ string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
+ if (display_timecode_on_stdout) {
+ printf("Timecode: '%s'\n", timecode_text.c_str());
+ }
+
+ // Get the main chain from the theme, and set its state immediately.
+ Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
+ EffectChain *chain = theme_main_chain.chain;
+ theme_main_chain.setup_chain();
+ //theme_main_chain.chain->enable_phase_timing(true);
+
+ // The theme can't (or at least shouldn't!) call connect_signal() on
+ // each FFmpeg input, so we'll do it here.
+ for (const pair<LiveInputWrapper *, FFmpegCapture *> &conn : theme->get_signal_connections()) {
+ conn.first->connect_signal_raw(conn.second->get_card_index());
+ }
+
+ // If HDMI/SDI output is active and the user has requested auto mode,
+ // its mode overrides the existing Y'CbCr setting for the chain.
+ YCbCrLumaCoefficients ycbcr_output_coefficients;
+ if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
+ ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
+ } else {
+ ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
+ }
+
+ // TODO: Reduce the duplication against theme.cpp.
+ YCbCrFormat output_ycbcr_format;
+ output_ycbcr_format.chroma_subsampling_x = 1;
+ output_ycbcr_format.chroma_subsampling_y = 1;
+ output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
+ output_ycbcr_format.full_range = false;
+ output_ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
+ chain->change_ycbcr_output_format(output_ycbcr_format);
+
+ // Render main chain. If we're using zerocopy Quick Sync encoding
+ // (the default case), we take an extra copy of the created outputs,
+ // so that we can display it back to the screen later (it's less memory
+ // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
+ // Ideally, we'd like to avoid taking copies and just use the main textures
+ // for display as well, but they're just views into VA-API memory and must be
+ // unmapped during encoding, so we can't use them for display, unfortunately.
+ GLuint y_tex, cbcr_full_tex, cbcr_tex;
+ GLuint y_copy_tex, cbcr_copy_tex = 0;
+ GLuint y_display_tex, cbcr_display_tex;
+ GLenum y_type = (global_flags.x264_bit_depth > 8) ? GL_R16 : GL_R8;
+ GLenum cbcr_type = (global_flags.x264_bit_depth > 8) ? GL_RG16 : GL_RG8;
+ const bool is_zerocopy = video_encoder->is_zerocopy();
+ if (is_zerocopy) {
+ cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
+ y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
+ cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
+
+ y_display_tex = y_copy_tex;
+ cbcr_display_tex = cbcr_copy_tex;
+
+ // y_tex and cbcr_tex will be given by VideoEncoder.
+ } else {
+ cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
+ y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
+ cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
+
+ y_display_tex = y_tex;
+ cbcr_display_tex = cbcr_tex;
+ }
+
+ const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE); // Corresponds to the delay in ResamplingQueue.
+ bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
+ assert(got_frame);
+
+ GLuint fbo;
+ if (is_zerocopy) {
+ fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
+ } else {
+ fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
+ }
+ check_error();
+ chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
+
+ if (display_timecode_in_stream) {
+ // Render the timecode on top.
+ timecode_renderer->render_timecode(fbo, timecode_text);
+ }
+
+ resource_pool->release_fbo(fbo);
+
+ if (is_zerocopy) {
+ chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
+ } else {
+ chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
+ }
+ if (output_card_index != -1) {
+ cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
+ }
+ resource_pool->release_2d_texture(cbcr_full_tex);
+
+ // Set the right state for the Y' and CbCr textures we use for display.
+ glBindFramebuffer(GL_FRAMEBUFFER, 0);
+ glBindTexture(GL_TEXTURE_2D, y_display_tex);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+ glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+ RefCountedGLsync fence = video_encoder->end_frame();
+
+ // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
+ // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
+ DisplayFrame live_frame;
+ live_frame.chain = display_chain.get();
+ live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
+ display_input->set_texture_num(0, y_display_tex);
+ display_input->set_texture_num(1, cbcr_display_tex);
+ };
+ live_frame.ready_fence = fence;
+ live_frame.input_frames = {};
+ live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
+ output_channel[OUTPUT_LIVE].output_frame(live_frame);
+
+ // Set up preview and any additional channels.
+ for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
+ DisplayFrame display_frame;
+ Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state); // FIXME: dimensions
+ display_frame.chain = chain.chain;
+ display_frame.setup_chain = chain.setup_chain;
+ display_frame.ready_fence = fence;
+ display_frame.input_frames = chain.input_frames;
+ display_frame.temp_textures = {};
+ output_channel[i].output_frame(display_frame);
+ }
+}
+
+void Mixer::audio_thread_func()
+{
+ pthread_setname_np(pthread_self(), "Mixer_Audio");
+
+ while (!should_quit) {
+ AudioTask task;
+
+ {
+ unique_lock<mutex> lock(audio_mutex);
+ audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
+ if (should_quit) {
+ return;
+ }
+ task = audio_task_queue.front();
+ audio_task_queue.pop();
+ }
+
+ ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
+ task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
+ vector<float> samples_out = audio_mixer.get_output(
+ task.frame_timestamp,
+ task.num_samples,
+ rate_adjustment_policy);
+
+ // Send the samples to the sound card, then add them to the output.
+ if (alsa) {
+ alsa->write(samples_out);
+ }
+ if (output_card_index != -1) {
+ const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE); // Corresponds to the delay in ResamplingQueue.
+ cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
+ }
+ video_encoder->add_audio(task.pts_int, move(samples_out));
+ }
+}
+
+void Mixer::release_display_frame(DisplayFrame *frame)
+{
+ for (GLuint texnum : frame->temp_textures) {
+ resource_pool->release_2d_texture(texnum);
+ }
+ frame->temp_textures.clear();
+ frame->ready_fence.reset();
+ frame->input_frames.clear();
+}
+
+void Mixer::start()
+{
+ mixer_thread = thread(&Mixer::thread_func, this);
+ audio_thread = thread(&Mixer::audio_thread_func, this);
+}
+
+void Mixer::quit()
+{
+ should_quit = true;
+ audio_task_queue_changed.notify_one();