]> git.sesse.net Git - nageru/blobdiff - mixer.cpp
Rename Resampler to ResamplingQueue, to avoid conflicts with zita-resampler.
[nageru] / mixer.cpp
index 9efb8ef1d611995b17e248e5c54a6cb8a169e7e4..6bf81192fdfd99421398dedc189e23be75344a5d 100644 (file)
--- a/mixer.cpp
+++ b/mixer.cpp
@@ -33,6 +33,7 @@
 
 #include "bmusb/bmusb.h"
 #include "context.h"
+#include "defs.h"
 #include "h264encode.h"
 #include "pbo_frame_allocator.h"
 #include "ref_counted_gl_sync.h"
@@ -68,7 +69,10 @@ Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
        : httpd("test.ts", WIDTH, HEIGHT),
          num_cards(num_cards),
          mixer_surface(create_surface(format)),
-         h264_encoder_surface(create_surface(format))
+         h264_encoder_surface(create_surface(format)),
+         level_compressor(OUTPUT_FREQUENCY),
+         limiter(OUTPUT_FREQUENCY),
+         compressor(OUTPUT_FREQUENCY)
 {
        httpd.start(9095);
 
@@ -111,7 +115,7 @@ Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
                card->usb->set_dequeue_thread_callbacks(
                        [card]{
                                eglBindAPI(EGL_OPENGL_API);
-                               card->context = create_context();
+                               card->context = create_context(card->surface);
                                if (!make_current(card->context, card->surface)) {
                                        printf("failed to create bmusb context\n");
                                        exit(1);
@@ -120,7 +124,7 @@ Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
                        [this]{
                                resource_pool->clean_context();
                        });
-               card->resampler.reset(new Resampler(48000.0, 48000.0, 2));
+               card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
                card->usb->configure_card();
        }
 
@@ -145,8 +149,10 @@ Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
                "} \n";
        cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader);
 
-       r128.init(2, 48000);
+       r128.init(2, OUTPUT_FREQUENCY);
        r128.integr_start();
+
+       locut.init(FILTER_HPF, 2);
 }
 
 Mixer::~Mixer()
@@ -240,21 +246,21 @@ void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
                unique_lock<mutex> lock(card->audio_mutex);
 
                int unwrapped_timecode = timecode;
-               if (dropped_frames > 60 * 2) {
+               if (dropped_frames > FPS * 2) {
                        fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around), resetting resampler\n",
                                card_index);
-                       card->resampler.reset(new Resampler(48000.0, 48000.0, 2));
+                       card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
                } else if (dropped_frames > 0) {
                        // Insert silence as needed.
                        fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
                                card_index, dropped_frames, timecode);
                        vector<float> silence;
-                       silence.resize((48000 / 60) * 2);
+                       silence.resize((OUTPUT_FREQUENCY / FPS) * 2);
                        for (int i = 0; i < dropped_frames; ++i) {
-                               card->resampler->add_input_samples((unwrapped_timecode - dropped_frames + i) / 60.0, silence.data(), (48000 / 60));
+                               card->resampling_queue->add_input_samples((unwrapped_timecode - dropped_frames + i) / double(FPS), silence.data(), (OUTPUT_FREQUENCY / FPS));
                        }
                }
-               card->resampler->add_input_samples(unwrapped_timecode / 60.0, audio.data(), num_samples);
+               card->resampling_queue->add_input_samples(unwrapped_timecode / double(FPS), audio.data(), num_samples);
        }
 
        // Done with the audio, so release it.
@@ -329,7 +335,7 @@ void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 void Mixer::thread_func()
 {
        eglBindAPI(EGL_OPENGL_API);
-       QOpenGLContext *context = create_context();
+       QOpenGLContext *context = create_context(mixer_surface);
        if (!make_current(context, mixer_surface)) {
                printf("oops\n");
                exit(1);
@@ -357,7 +363,6 @@ void Mixer::thread_func()
                                card_copy[card_index].new_data_ready = card->new_data_ready;
                                card_copy[card_index].new_frame = card->new_frame;
                                card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
-                               card_copy[card_index].new_frame_audio = move(card->new_frame_audio);
                                card_copy[card_index].dropped_frames = card->dropped_frames;
                                card->new_data_ready = false;
                                card->new_data_ready_changed.notify_all();
@@ -365,30 +370,12 @@ void Mixer::thread_func()
                }
 
                // Resample the audio as needed, including from previously dropped frames.
-               vector<float> samples_out;
-               // TODO: Allow using audio from the other card(s) as well.
                for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
-                       for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
-                               samples_out.resize((48000 / 60) * 2);
-                               {
-                                       unique_lock<mutex> lock(cards[card_index].audio_mutex);
-                                       if (!cards[card_index].resampler->get_output_samples(pts(), &samples_out[0], 48000 / 60)) {
-                                               printf("Card %d reported previous underrun.\n", card_index);
-                                       }
-                               }
-                               if (card_index == 0) {
-                                       vector<float> left, right;
-                                       peak = std::max(peak, find_peak(samples_out));
-                                       deinterleave_samples(samples_out, &left, &right);
-                                       float *ptrs[] = { left.data(), right.data() };
-                                       r128.process(left.size(), ptrs);
-                                       h264_encoder->add_audio(pts_int, move(samples_out));
-                               }
-                       }
+                       process_audio_one_frame();
                        if (frame_num != card_copy[0].dropped_frames) {
                                // For dropped frames, increase the pts.
                                ++dropped_frames;
-                               pts_int += TIMEBASE / 60;
+                               pts_int += TIMEBASE / FPS;
                        }
                }
 
@@ -399,7 +386,8 @@ void Mixer::thread_func()
                        double loudness_range_high = r128.range_max();
 
                        audio_level_callback(loudness_s, 20.0 * log10(peak),
-                                            loudness_i, loudness_range_low, loudness_range_high);
+                                            loudness_i, loudness_range_low, loudness_range_high,
+                                            last_gain_staging_db);
                }
 
                for (unsigned card_index = 1; card_index < num_cards; ++card_index) {
@@ -416,7 +404,7 @@ void Mixer::thread_func()
                // just increase the pts (skipping over this frame) and don't try to compute anything new.
                if (card_copy[0].new_frame->len == 0) {
                        ++dropped_frames;
-                       pts_int += TIMEBASE / 60;
+                       pts_int += TIMEBASE / FPS;
                        continue;
                }
 
@@ -478,10 +466,10 @@ void Mixer::thread_func()
                for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
                        input_frames.push_back(bmusb_current_rendering_frame[card_index]);
                }
-               const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampler.h. TODO: Make less hard-coded.
+               const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
                h264_encoder->end_frame(fence, pts_int + av_delay, input_frames);
                ++frame;
-               pts_int += TIMEBASE / 60;
+               pts_int += TIMEBASE / FPS;
 
                // The live frame just shows the RGBA texture we just rendered.
                // It owns rgba_tex now.
@@ -537,6 +525,92 @@ void Mixer::thread_func()
        resource_pool->clean_context();
 }
 
+void Mixer::process_audio_one_frame()
+{
+       vector<float> samples_card;
+       vector<float> samples_out;
+       for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
+               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)) {
+                               printf("Card %d reported previous underrun.\n", card_index);
+                       }
+               }
+               // TODO: Allow using audio from the other card(s) as well.
+               if (card_index == 0) {
+                       samples_out = move(samples_card);
+               }
+       }
+
+       // Cut away everything under 150 Hz; we don't need it for voice,
+       // and it will reduce headroom and confuse the compressor.
+       // (In particular, any hums at 50 or 60 Hz should be dampened.)
+       locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
+
+       // Apply a level compressor to get the general level right.
+       // Basically, if it's over about -40 dBFS, we squeeze it down to that level
+       // (or more precisely, near it, since we don't use infinite ratio),
+       // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
+       // entirely arbitrary, but from practical tests with speech, it seems to
+       // put ut around -23 LUFS, so it's a reasonable starting point for later use.
+       float ref_level_dbfs = -14.0f;
+       {
+               float threshold = 0.01f;   // -40 dBFS.
+               float ratio = 20.0f;
+               float attack_time = 0.5f;
+               float release_time = 20.0f;
+               float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f);  // +26 dB.
+               level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
+               last_gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
+       }
+
+#if 0
+       printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
+               level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
+               level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
+               20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
+#endif
+
+//     float limiter_att, compressor_att;
+
+       // Then a limiter at +0 dB (so, -14 dBFS) to take out the worst peaks only.
+       // Note that since ratio is not infinite, we could go slightly higher than this.
+       // Probably more tuning is warranted here.
+       {
+               float threshold = pow(10.0f, (ref_level_dbfs + 0.0f) / 20.0f);  // +0 dB.
+               float ratio = 30.0f;
+               float attack_time = 0.0f;  // Instant.
+               float release_time = 0.005f;
+               float makeup_gain = 1.0f;  // 0 dB.
+               limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
+//             limiter_att = limiter.get_attenuation();
+       }
+
+       // Finally, the real compressor.
+       {
+               float threshold = pow(10.0f, (ref_level_dbfs - 12.0f) / 20.0f);  // -12 dB.
+               float ratio = 20.0f;
+               float attack_time = 0.005f;
+               float release_time = 0.040f;
+               float makeup_gain = 2.0f;  // +6 dB.
+               compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
+//             compressor_att = compressor.get_attenuation();
+       }
+
+//     printf("limiter=%+5.1f  compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
+
+       // Find peak and R128 levels.
+       peak = max<float>(peak, find_peak(samples_out));
+       vector<float> left, right;
+       deinterleave_samples(samples_out, &left, &right);
+       float *ptrs[] = { left.data(), right.data() };
+       r128.process(left.size(), ptrs);
+
+       // Actually add the samples to the output.
+       h264_encoder->add_audio(pts_int, move(samples_out));
+}
+
 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 {
        GLuint vao;
@@ -622,6 +696,13 @@ void Mixer::channel_clicked(int preview_num)
        theme->channel_clicked(preview_num);
 }
 
+void Mixer::reset_meters()
+{
+       peak = 0.0f;
+       r128.reset();
+       r128.integr_start();
+}
+
 Mixer::OutputChannel::~OutputChannel()
 {
        if (has_current_frame) {