Move audio processing into a thread, since it seems we want as little as possible...

[nageru] / mixer.cpp

diff --git a/mixer.cpp b/mixer.cpp
index f044ecd2f743c24855eefb474cfb2a158341fb01..239575f6dc82a1c969597474d425b75f47a8b638 100644 (file)
--- a/mixer.cpp
+++ b/mixer.cpp
@@ -379,7 +379,12 @@ void Mixer::thread_func()
 
                // Resample the audio as needed, including from previously dropped frames.
                for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
-                       process_audio_one_frame();
+                       {
+                               // Signal to the audio thread to process this frame.
+                               unique_lock<mutex> lock(audio_mutex);
+                               audio_pts_queue.push(pts_int);
+                               audio_pts_queue_changed.notify_one();
+                       }
                        if (frame_num != card_copy[0].dropped_frames) {
                                // For dropped frames, increase the pts.
                                ++dropped_frames;
@@ -533,7 +538,23 @@ void Mixer::thread_func()
        resource_pool->clean_context();
 }
 
-void Mixer::process_audio_one_frame()
+void Mixer::audio_thread_func()
+{
+       while (!should_quit) {
+               int64_t frame_pts_int;
+
+               {
+                       unique_lock<mutex> lock(audio_mutex);
+                       audio_pts_queue_changed.wait(lock, [this]{ return !audio_pts_queue.empty(); });
+                       frame_pts_int = audio_pts_queue.front();
+                       audio_pts_queue.pop();
+               }
+
+               process_audio_one_frame(frame_pts_int);
+       }
+}
+
+void Mixer::process_audio_one_frame(int64_t frame_pts_int)
 {
        vector<float> samples_card;
        vector<float> samples_out;
@@ -541,7 +562,7 @@ void Mixer::process_audio_one_frame()
                samples_card.resize((OUTPUT_FREQUENCY / FPS) * 2);
                {
                        unique_lock<mutex> lock(cards[card_index].audio_mutex);
-                       if (!cards[card_index].resampling_queue->get_output_samples(pts(), &samples_card[0], OUTPUT_FREQUENCY / FPS)) {
+                       if (!cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], OUTPUT_FREQUENCY / FPS)) {
                                printf("Card %d reported previous underrun.\n", card_index);
                        }
                }
@@ -633,7 +654,7 @@ void Mixer::process_audio_one_frame()
        }
 
        // And finally add them to the output.
-       h264_encoder->add_audio(pts_int, move(samples_out));
+       h264_encoder->add_audio(frame_pts_int, move(samples_out));
 }
 
 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
@@ -703,12 +724,14 @@ void Mixer::release_display_frame(DisplayFrame *frame)
 void Mixer::start()
 {
        mixer_thread = thread(&Mixer::thread_func, this);
+       audio_thread = thread(&Mixer::audio_thread_func, this);
 }
 
 void Mixer::quit()
 {
        should_quit = true;
        mixer_thread.join();
+       audio_thread.join();
 }
 
 void Mixer::transition_clicked(int transition_num)