]> git.sesse.net Git - nageru/blob - mixer.cpp
Make audio input source selectable.
[nageru] / mixer.cpp
1 #undef Success
2
3 #include "mixer.h"
4
5 #include <assert.h>
6 #include <epoxy/egl.h>
7 #include <init.h>
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>
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 = read_file("vs-cbcr.130.vert");
171         string cbcr_frag_shader =
172                 "#version 130 \n"
173                 "in vec2 tc0; \n"
174                 "uniform sampler2D cbcr_tex; \n"
175                 "void main() { \n"
176                 "    gl_FragColor = texture2D(cbcr_tex, tc0); \n"
177                 "} \n";
178         vector<string> frag_shader_outputs;
179         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
180
181         r128.init(2, OUTPUT_FREQUENCY);
182         r128.integr_start();
183
184         locut.init(FILTER_HPF, 2);
185
186         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
187         // and there's a limit to how important the peak meter is.
188         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16, /*frel=*/1.0);
189
190         alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
191 }
192
193 Mixer::~Mixer()
194 {
195         resource_pool->release_glsl_program(cbcr_program_num);
196         BMUSBCapture::stop_bm_thread();
197
198         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
199                 {
200                         unique_lock<mutex> lock(bmusb_mutex);
201                         cards[card_index].should_quit = true;  // Unblock thread.
202                         cards[card_index].new_data_ready_changed.notify_all();
203                 }
204                 cards[card_index].usb->stop_dequeue_thread();
205         }
206
207         h264_encoder.reset(nullptr);
208 }
209
210 namespace {
211
212 int unwrap_timecode(uint16_t current_wrapped, int last)
213 {
214         uint16_t last_wrapped = last & 0xffff;
215         if (current_wrapped > last_wrapped) {
216                 return (last & ~0xffff) | current_wrapped;
217         } else {
218                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
219         }
220 }
221
222 float find_peak(const float *samples, size_t num_samples)
223 {
224         float m = fabs(samples[0]);
225         for (size_t i = 1; i < num_samples; ++i) {
226                 m = max(m, fabs(samples[i]));
227         }
228         return m;
229 }
230
231 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
232 {
233         size_t num_samples = in.size() / 2;
234         out_l->resize(num_samples);
235         out_r->resize(num_samples);
236
237         const float *inptr = in.data();
238         float *lptr = &(*out_l)[0];
239         float *rptr = &(*out_r)[0];
240         for (size_t i = 0; i < num_samples; ++i) {
241                 *lptr++ = *inptr++;
242                 *rptr++ = *inptr++;
243         }
244 }
245
246 }  // namespace
247
248 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
249                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
250                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
251 {
252         CaptureCard *card = &cards[card_index];
253
254         unsigned width, height, second_field_start, frame_rate_nom, frame_rate_den, extra_lines_top, extra_lines_bottom;
255         bool interlaced;
256
257         decode_video_format(video_format, &width, &height, &second_field_start, &extra_lines_top, &extra_lines_bottom,
258                             &frame_rate_nom, &frame_rate_den, &interlaced);  // Ignore return value for now.
259         int64_t frame_length = int64_t(TIMEBASE * frame_rate_den) / frame_rate_nom;
260
261         size_t num_samples = (audio_frame.len >= audio_offset) ? (audio_frame.len - audio_offset) / 8 / 3 : 0;
262         if (num_samples > OUTPUT_FREQUENCY / 10) {
263                 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",
264                         card_index, int(audio_frame.len), int(audio_offset),
265                         timecode, int(video_frame.len), int(video_offset), video_format);
266                 if (video_frame.owner) {
267                         video_frame.owner->release_frame(video_frame);
268                 }
269                 if (audio_frame.owner) {
270                         audio_frame.owner->release_frame(audio_frame);
271                 }
272                 return;
273         }
274
275         int64_t local_pts = card->next_local_pts;
276         int dropped_frames = 0;
277         if (card->last_timecode != -1) {
278                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
279         }
280
281         // Convert the audio to stereo fp32 and add it.
282         vector<float> audio;
283         audio.resize(num_samples * 2);
284         convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
285
286         // Add the audio.
287         {
288                 unique_lock<mutex> lock(card->audio_mutex);
289
290                 // Number of samples per frame if we need to insert silence.
291                 // (Could be nonintegral, but resampling will save us then.)
292                 int silence_samples = OUTPUT_FREQUENCY * frame_rate_den / frame_rate_nom;
293
294                 if (dropped_frames > MAX_FPS * 2) {
295                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
296                                 card_index, card->last_timecode, timecode);
297                         card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
298                         dropped_frames = 0;
299                 } else if (dropped_frames > 0) {
300                         // Insert silence as needed.
301                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
302                                 card_index, dropped_frames, timecode);
303                         vector<float> silence(silence_samples * 2, 0.0f);
304                         for (int i = 0; i < dropped_frames; ++i) {
305                                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), silence.data(), silence_samples);
306                                 // Note that if the format changed in the meantime, we have
307                                 // no way of detecting that; we just have to assume the frame length
308                                 // is always the same.
309                                 local_pts += frame_length;
310                         }
311                 }
312                 if (num_samples == 0) {
313                         audio.resize(silence_samples * 2);
314                         num_samples = silence_samples;
315                 }
316                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), audio.data(), num_samples);
317                 card->next_local_pts = local_pts + frame_length;
318         }
319
320         card->last_timecode = timecode;
321
322         // Done with the audio, so release it.
323         if (audio_frame.owner) {
324                 audio_frame.owner->release_frame(audio_frame);
325         }
326
327         {
328                 // Wait until the previous frame was consumed.
329                 unique_lock<mutex> lock(bmusb_mutex);
330                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
331                 if (card->should_quit) return;
332         }
333
334         size_t expected_length = width * (height + extra_lines_top + extra_lines_bottom) * 2;
335         if (video_frame.len - video_offset == 0 ||
336             video_frame.len - video_offset != expected_length) {
337                 if (video_frame.len != 0) {
338                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
339                                 card_index, video_frame.len - video_offset, expected_length);
340                 }
341                 if (video_frame.owner) {
342                         video_frame.owner->release_frame(video_frame);
343                 }
344
345                 // Still send on the information that we _had_ a frame, even though it's corrupted,
346                 // so that pts can go up accordingly.
347                 {
348                         unique_lock<mutex> lock(bmusb_mutex);
349                         card->new_data_ready = true;
350                         card->new_frame = RefCountedFrame(FrameAllocator::Frame());
351                         card->new_frame_length = frame_length;
352                         card->new_frame_interlaced = false;
353                         card->new_data_ready_fence = nullptr;
354                         card->dropped_frames = dropped_frames;
355                         card->new_data_ready_changed.notify_all();
356                 }
357                 return;
358         }
359
360         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
361
362         unsigned num_fields = interlaced ? 2 : 1;
363         timespec frame_upload_start;
364         if (interlaced) {
365                 // Send the two fields along as separate frames; the other side will need to add
366                 // a deinterlacer to actually get this right.
367                 assert(height % 2 == 0);
368                 height /= 2;
369                 assert(frame_length % 2 == 0);
370                 frame_length /= 2;
371                 num_fields = 2;
372                 clock_gettime(CLOCK_MONOTONIC, &frame_upload_start);
373         }
374         userdata->last_interlaced = interlaced;
375         userdata->last_frame_rate_nom = frame_rate_nom;
376         userdata->last_frame_rate_den = frame_rate_den;
377         RefCountedFrame new_frame(video_frame);
378
379         // Upload the textures.
380         size_t cbcr_width = width / 2;
381         size_t cbcr_offset = video_offset / 2;
382         size_t y_offset = video_frame.size / 2 + video_offset / 2;
383
384         for (unsigned field = 0; field < num_fields; ++field) {
385                 unsigned field_start_line = (field == 1) ? second_field_start : extra_lines_top + field * (height + 22);
386
387                 if (userdata->tex_y[field] == 0 ||
388                     userdata->tex_cbcr[field] == 0 ||
389                     width != userdata->last_width[field] ||
390                     height != userdata->last_height[field]) {
391                         // We changed resolution since last use of this texture, so we need to create
392                         // a new object. Note that this each card has its own PBOFrameAllocator,
393                         // we don't need to worry about these flip-flopping between resolutions.
394                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
395                         check_error();
396                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
397                         check_error();
398                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
399                         check_error();
400                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
401                         check_error();
402                         userdata->last_width[field] = width;
403                         userdata->last_height[field] = height;
404                 }
405
406                 GLuint pbo = userdata->pbo;
407                 check_error();
408                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
409                 check_error();
410                 glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
411                 check_error();
412
413                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
414                 check_error();
415                 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)));
416                 check_error();
417                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
418                 check_error();
419                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(y_offset + width * field_start_line));
420                 check_error();
421                 glBindTexture(GL_TEXTURE_2D, 0);
422                 check_error();
423                 GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
424                 check_error();
425                 assert(fence != nullptr);
426
427                 if (field == 1) {
428                         // Don't upload the second field as fast as we can; wait until
429                         // the field time has approximately passed. (Otherwise, we could
430                         // get timing jitter against the other sources, and possibly also
431                         // against the video display, although the latter is not as critical.)
432                         // This requires our system clock to be reasonably close to the
433                         // video clock, but that's not an unreasonable assumption.
434                         timespec second_field_start;
435                         second_field_start.tv_nsec = frame_upload_start.tv_nsec +
436                                 frame_length * 1000000000 / TIMEBASE;
437                         second_field_start.tv_sec = frame_upload_start.tv_sec +
438                                 second_field_start.tv_nsec / 1000000000;
439                         second_field_start.tv_nsec %= 1000000000;
440
441                         while (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
442                                                &second_field_start, nullptr) == -1 &&
443                                errno == EINTR) ;
444                 }
445
446                 {
447                         unique_lock<mutex> lock(bmusb_mutex);
448                         card->new_data_ready = true;
449                         card->new_frame = new_frame;
450                         card->new_frame_length = frame_length;
451                         card->new_frame_field = field;
452                         card->new_frame_interlaced = interlaced;
453                         card->new_data_ready_fence = fence;
454                         card->dropped_frames = dropped_frames;
455                         card->new_data_ready_changed.notify_all();
456
457                         if (field != num_fields - 1) {
458                                 // Wait until the previous frame was consumed.
459                                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
460                                 if (card->should_quit) return;
461                         }
462                 }
463         }
464 }
465
466 void Mixer::thread_func()
467 {
468         eglBindAPI(EGL_OPENGL_API);
469         QOpenGLContext *context = create_context(mixer_surface);
470         if (!make_current(context, mixer_surface)) {
471                 printf("oops\n");
472                 exit(1);
473         }
474
475         struct timespec start, now;
476         clock_gettime(CLOCK_MONOTONIC, &start);
477
478         int frame = 0;
479         int stats_dropped_frames = 0;
480
481         while (!should_quit) {
482                 CaptureCard card_copy[MAX_CARDS];
483                 int num_samples[MAX_CARDS];
484
485                 {
486                         unique_lock<mutex> lock(bmusb_mutex);
487
488                         // The first card is the master timer, so wait for it to have a new frame.
489                         // TODO: Make configurable, and with a timeout.
490                         cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
491
492                         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
493                                 CaptureCard *card = &cards[card_index];
494                                 card_copy[card_index].usb = card->usb;
495                                 card_copy[card_index].new_data_ready = card->new_data_ready;
496                                 card_copy[card_index].new_frame = card->new_frame;
497                                 card_copy[card_index].new_frame_length = card->new_frame_length;
498                                 card_copy[card_index].new_frame_field = card->new_frame_field;
499                                 card_copy[card_index].new_frame_interlaced = card->new_frame_interlaced;
500                                 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
501                                 card_copy[card_index].dropped_frames = card->dropped_frames;
502                                 card->new_data_ready = false;
503                                 card->new_data_ready_changed.notify_all();
504
505                                 int num_samples_times_timebase = OUTPUT_FREQUENCY * card->new_frame_length + card->fractional_samples;
506                                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
507                                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
508                                 assert(num_samples[card_index] >= 0);
509                         }
510                 }
511
512                 // Resample the audio as needed, including from previously dropped frames.
513                 assert(num_cards > 0);
514                 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
515                         {
516                                 // Signal to the audio thread to process this frame.
517                                 unique_lock<mutex> lock(audio_mutex);
518                                 audio_task_queue.push(AudioTask{pts_int, num_samples[0]});
519                                 audio_task_queue_changed.notify_one();
520                         }
521                         if (frame_num != card_copy[0].dropped_frames) {
522                                 // For dropped frames, increase the pts. Note that if the format changed
523                                 // in the meantime, we have no way of detecting that; we just have to
524                                 // assume the frame length is always the same.
525                                 ++stats_dropped_frames;
526                                 pts_int += card_copy[0].new_frame_length;
527                         }
528                 }
529
530                 if (audio_level_callback != nullptr) {
531                         unique_lock<mutex> lock(compressor_mutex);
532                         double loudness_s = r128.loudness_S();
533                         double loudness_i = r128.integrated();
534                         double loudness_range_low = r128.range_min();
535                         double loudness_range_high = r128.range_max();
536
537                         audio_level_callback(loudness_s, 20.0 * log10(peak),
538                                              loudness_i, loudness_range_low, loudness_range_high,
539                                              gain_staging_db, 20.0 * log10(final_makeup_gain),
540                                              correlation.get_correlation());
541                 }
542
543                 for (unsigned card_index = 1; card_index < num_cards; ++card_index) {
544                         if (card_copy[card_index].new_data_ready && card_copy[card_index].new_frame->len == 0) {
545                                 ++card_copy[card_index].dropped_frames;
546                         }
547                         if (card_copy[card_index].dropped_frames > 0) {
548                                 printf("Card %u dropped %d frames before this\n",
549                                         card_index, int(card_copy[card_index].dropped_frames));
550                         }
551                 }
552
553                 // If the first card is reporting a corrupted or otherwise dropped frame,
554                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
555                 if (card_copy[0].new_frame->len == 0) {
556                         ++stats_dropped_frames;
557                         pts_int += card_copy[0].new_frame_length;
558                         continue;
559                 }
560
561                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
562                         CaptureCard *card = &card_copy[card_index];
563                         if (!card->new_data_ready || card->new_frame->len == 0)
564                                 continue;
565
566                         assert(card->new_frame != nullptr);
567                         insert_new_frame(card->new_frame, card->new_frame_field, card->new_frame_interlaced, card_index, &input_state);
568                         check_error();
569
570                         // The new texture might still be uploaded,
571                         // tell the GPU to wait until it's there.
572                         if (card->new_data_ready_fence) {
573                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
574                                 check_error();
575                                 glDeleteSync(card->new_data_ready_fence);
576                                 check_error();
577                         }
578                 }
579
580                 // Get the main chain from the theme, and set its state immediately.
581                 Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
582                 EffectChain *chain = theme_main_chain.chain;
583                 theme_main_chain.setup_chain();
584                 //theme_main_chain.chain->enable_phase_timing(true);
585
586                 GLuint y_tex, cbcr_tex;
587                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
588                 assert(got_frame);
589
590                 // Render main chain.
591                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
592                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
593                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
594                 check_error();
595                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
596                 resource_pool->release_fbo(fbo);
597
598                 subsample_chroma(cbcr_full_tex, cbcr_tex);
599                 resource_pool->release_2d_texture(cbcr_full_tex);
600
601                 // Set the right state for rgba_tex.
602                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
603                 glBindTexture(GL_TEXTURE_2D, rgba_tex);
604                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
605                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
606                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
607
608                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
609                 check_error();
610
611                 const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
612                 h264_encoder->end_frame(fence, pts_int + av_delay, theme_main_chain.input_frames);
613                 ++frame;
614                 pts_int += card_copy[0].new_frame_length;
615
616                 // The live frame just shows the RGBA texture we just rendered.
617                 // It owns rgba_tex now.
618                 DisplayFrame live_frame;
619                 live_frame.chain = display_chain.get();
620                 live_frame.setup_chain = [this, rgba_tex]{
621                         display_input->set_texture_num(rgba_tex);
622                 };
623                 live_frame.ready_fence = fence;
624                 live_frame.input_frames = {};
625                 live_frame.temp_textures = { rgba_tex };
626                 output_channel[OUTPUT_LIVE].output_frame(live_frame);
627
628                 // Set up preview and any additional channels.
629                 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
630                         DisplayFrame display_frame;
631                         Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
632                         display_frame.chain = chain.chain;
633                         display_frame.setup_chain = chain.setup_chain;
634                         display_frame.ready_fence = fence;
635                         display_frame.input_frames = chain.input_frames;
636                         display_frame.temp_textures = {};
637                         output_channel[i].output_frame(display_frame);
638                 }
639
640                 clock_gettime(CLOCK_MONOTONIC, &now);
641                 double elapsed = now.tv_sec - start.tv_sec +
642                         1e-9 * (now.tv_nsec - start.tv_nsec);
643                 if (frame % 100 == 0) {
644                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
645                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
646                                 1e3 * elapsed / frame);
647                 //      chain->print_phase_timing();
648                 }
649
650                 if (should_cut.exchange(false)) {  // Test and clear.
651                         string filename = generate_local_dump_filename(frame);
652                         printf("Starting new recording: %s\n", filename.c_str());
653                         h264_encoder->shutdown();
654                         httpd.close_output_file();
655                         httpd.open_output_file(filename.c_str());
656                         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
657                 }
658
659 #if 0
660                 // Reset every 100 frames, so that local variations in frame times
661                 // (especially for the first few frames, when the shaders are
662                 // compiled etc.) don't make it hard to measure for the entire
663                 // remaining duration of the program.
664                 if (frame == 10000) {
665                         frame = 0;
666                         start = now;
667                 }
668 #endif
669                 check_error();
670         }
671
672         resource_pool->clean_context();
673 }
674
675 void Mixer::audio_thread_func()
676 {
677         while (!should_quit) {
678                 AudioTask task;
679
680                 {
681                         unique_lock<mutex> lock(audio_mutex);
682                         audio_task_queue_changed.wait(lock, [this]{ return !audio_task_queue.empty(); });
683                         task = audio_task_queue.front();
684                         audio_task_queue.pop();
685                 }
686
687                 process_audio_one_frame(task.pts_int, task.num_samples);
688         }
689 }
690
691 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples)
692 {
693         vector<float> samples_card;
694         vector<float> samples_out;
695
696         // TODO: Allow mixing audio from several sources.
697         unsigned selected_audio_card = theme->map_signal(audio_source_channel);
698         assert(selected_audio_card < num_cards);
699
700         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
701                 samples_card.resize(num_samples * 2);
702                 {
703                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
704                         if (!cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], num_samples)) {
705                                 printf("Card %d reported previous underrun.\n", card_index);
706                         }
707                 }
708                 if (card_index == selected_audio_card) {
709                         samples_out = move(samples_card);
710                 }
711         }
712
713         // Cut away everything under 120 Hz (or whatever the cutoff is);
714         // we don't need it for voice, and it will reduce headroom
715         // and confuse the compressor. (In particular, any hums at 50 or 60 Hz
716         // should be dampened.)
717         if (locut_enabled) {
718                 locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
719         }
720
721         // Apply a level compressor to get the general level right.
722         // Basically, if it's over about -40 dBFS, we squeeze it down to that level
723         // (or more precisely, near it, since we don't use infinite ratio),
724         // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
725         // entirely arbitrary, but from practical tests with speech, it seems to
726         // put ut around -23 LUFS, so it's a reasonable starting point for later use.
727         {
728                 unique_lock<mutex> lock(compressor_mutex);
729                 if (level_compressor_enabled) {
730                         float threshold = 0.01f;   // -40 dBFS.
731                         float ratio = 20.0f;
732                         float attack_time = 0.5f;
733                         float release_time = 20.0f;
734                         float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f);  // +26 dB.
735                         level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
736                         gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
737                 } else {
738                         // Just apply the gain we already had.
739                         float g = pow(10.0f, gain_staging_db / 20.0f);
740                         for (size_t i = 0; i < samples_out.size(); ++i) {
741                                 samples_out[i] *= g;
742                         }
743                 }
744         }
745
746 #if 0
747         printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
748                 level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
749                 level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
750                 20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
751 #endif
752
753 //      float limiter_att, compressor_att;
754
755         // The real compressor.
756         if (compressor_enabled) {
757                 float threshold = pow(10.0f, compressor_threshold_dbfs / 20.0f);
758                 float ratio = 20.0f;
759                 float attack_time = 0.005f;
760                 float release_time = 0.040f;
761                 float makeup_gain = 2.0f;  // +6 dB.
762                 compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
763 //              compressor_att = compressor.get_attenuation();
764         }
765
766         // Finally a limiter at -4 dB (so, -10 dBFS) to take out the worst peaks only.
767         // Note that since ratio is not infinite, we could go slightly higher than this.
768         if (limiter_enabled) {
769                 float threshold = pow(10.0f, limiter_threshold_dbfs / 20.0f);
770                 float ratio = 30.0f;
771                 float attack_time = 0.0f;  // Instant.
772                 float release_time = 0.020f;
773                 float makeup_gain = 1.0f;  // 0 dB.
774                 limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
775 //              limiter_att = limiter.get_attenuation();
776         }
777
778 //      printf("limiter=%+5.1f  compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
779
780         // Upsample 4x to find interpolated peak.
781         peak_resampler.inp_data = samples_out.data();
782         peak_resampler.inp_count = samples_out.size() / 2;
783
784         vector<float> interpolated_samples_out;
785         interpolated_samples_out.resize(samples_out.size());
786         while (peak_resampler.inp_count > 0) {  // About four iterations.
787                 peak_resampler.out_data = &interpolated_samples_out[0];
788                 peak_resampler.out_count = interpolated_samples_out.size() / 2;
789                 peak_resampler.process();
790                 size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
791                 peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
792                 peak_resampler.out_data = nullptr;
793         }
794
795         // At this point, we are most likely close to +0 LU, but all of our
796         // measurements have been on raw sample values, not R128 values.
797         // So we have a final makeup gain to get us to +0 LU; the gain
798         // adjustments required should be relatively small, and also, the
799         // offset shouldn't change much (only if the type of audio changes
800         // significantly). Thus, we shoot for updating this value basically
801         // “whenever we process buffers”, since the R128 calculation isn't exactly
802         // something we get out per-sample.
803         //
804         // Note that there's a feedback loop here, so we choose a very slow filter
805         // (half-time of 100 seconds).
806         double target_loudness_factor, alpha;
807         {
808                 unique_lock<mutex> lock(compressor_mutex);
809                 double loudness_lu = r128.loudness_M() - ref_level_lufs;
810                 double current_makeup_lu = 20.0f * log10(final_makeup_gain);
811                 target_loudness_factor = pow(10.0f, -loudness_lu / 20.0f);
812
813                 // If we're outside +/- 5 LU uncorrected, we don't count it as
814                 // a normal signal (probably silence) and don't change the
815                 // correction factor; just apply what we already have.
816                 if (fabs(loudness_lu - current_makeup_lu) >= 5.0 || !final_makeup_gain_auto) {
817                         alpha = 0.0;
818                 } else {
819                         // Formula adapted from
820                         // https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter.
821                         const double half_time_s = 100.0;
822                         const double fc_mul_2pi_delta_t = 1.0 / (half_time_s * OUTPUT_FREQUENCY);
823                         alpha = fc_mul_2pi_delta_t / (fc_mul_2pi_delta_t + 1.0);
824                 }
825
826                 double m = final_makeup_gain;
827                 for (size_t i = 0; i < samples_out.size(); i += 2) {
828                         samples_out[i + 0] *= m;
829                         samples_out[i + 1] *= m;
830                         m += (target_loudness_factor - m) * alpha;
831                 }
832                 final_makeup_gain = m;
833         }
834
835         // Find R128 levels and L/R correlation.
836         vector<float> left, right;
837         deinterleave_samples(samples_out, &left, &right);
838         float *ptrs[] = { left.data(), right.data() };
839         {
840                 unique_lock<mutex> lock(compressor_mutex);
841                 r128.process(left.size(), ptrs);
842                 correlation.process_samples(samples_out);
843         }
844
845         // Send the samples to the sound card.
846         if (alsa) {
847                 alsa->write(samples_out);
848         }
849
850         // And finally add them to the output.
851         h264_encoder->add_audio(frame_pts_int, move(samples_out));
852 }
853
854 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
855 {
856         GLuint vao;
857         glGenVertexArrays(1, &vao);
858         check_error();
859
860         float vertices[] = {
861                 0.0f, 2.0f,
862                 0.0f, 0.0f,
863                 2.0f, 0.0f
864         };
865
866         glBindVertexArray(vao);
867         check_error();
868
869         // Extract Cb/Cr.
870         GLuint fbo = resource_pool->create_fbo(dst_tex);
871         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
872         glViewport(0, 0, WIDTH/2, HEIGHT/2);
873         check_error();
874
875         glUseProgram(cbcr_program_num);
876         check_error();
877
878         glActiveTexture(GL_TEXTURE0);
879         check_error();
880         glBindTexture(GL_TEXTURE_2D, src_tex);
881         check_error();
882         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
883         check_error();
884         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
885         check_error();
886         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
887         check_error();
888
889         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
890         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
891
892         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
893         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
894
895         glDrawArrays(GL_TRIANGLES, 0, 3);
896         check_error();
897
898         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
899         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
900
901         glUseProgram(0);
902         check_error();
903
904         resource_pool->release_fbo(fbo);
905         glDeleteVertexArrays(1, &vao);
906 }
907
908 void Mixer::release_display_frame(DisplayFrame *frame)
909 {
910         for (GLuint texnum : frame->temp_textures) {
911                 resource_pool->release_2d_texture(texnum);
912         }
913         frame->temp_textures.clear();
914         frame->ready_fence.reset();
915         frame->input_frames.clear();
916 }
917
918 void Mixer::start()
919 {
920         mixer_thread = thread(&Mixer::thread_func, this);
921         audio_thread = thread(&Mixer::audio_thread_func, this);
922 }
923
924 void Mixer::quit()
925 {
926         should_quit = true;
927         mixer_thread.join();
928         audio_thread.join();
929 }
930
931 void Mixer::transition_clicked(int transition_num)
932 {
933         theme->transition_clicked(transition_num, pts());
934 }
935
936 void Mixer::channel_clicked(int preview_num)
937 {
938         theme->channel_clicked(preview_num);
939 }
940
941 void Mixer::reset_meters()
942 {
943         peak_resampler.reset();
944         peak = 0.0f;
945         r128.reset();
946         r128.integr_start();
947         correlation.reset();
948 }
949
950 Mixer::OutputChannel::~OutputChannel()
951 {
952         if (has_current_frame) {
953                 parent->release_display_frame(&current_frame);
954         }
955         if (has_ready_frame) {
956                 parent->release_display_frame(&ready_frame);
957         }
958 }
959
960 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
961 {
962         // Store this frame for display. Remove the ready frame if any
963         // (it was seemingly never used).
964         {
965                 unique_lock<mutex> lock(frame_mutex);
966                 if (has_ready_frame) {
967                         parent->release_display_frame(&ready_frame);
968                 }
969                 ready_frame = frame;
970                 has_ready_frame = true;
971         }
972
973         if (has_new_frame_ready_callback) {
974                 new_frame_ready_callback();
975         }
976 }
977
978 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
979 {
980         unique_lock<mutex> lock(frame_mutex);
981         if (!has_current_frame && !has_ready_frame) {
982                 return false;
983         }
984
985         if (has_current_frame && has_ready_frame) {
986                 // We have a new ready frame. Toss the current one.
987                 parent->release_display_frame(&current_frame);
988                 has_current_frame = false;
989         }
990         if (has_ready_frame) {
991                 assert(!has_current_frame);
992                 current_frame = ready_frame;
993                 ready_frame.ready_fence.reset();  // Drop the refcount.
994                 ready_frame.input_frames.clear();  // Drop the refcounts.
995                 has_current_frame = true;
996                 has_ready_frame = false;
997         }
998
999         *frame = current_frame;
1000         return true;
1001 }
1002
1003 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1004 {
1005         new_frame_ready_callback = callback;
1006         has_new_frame_ready_callback = true;
1007 }