]> git.sesse.net Git - nageru/blob - mixer.cpp
Ease debugging of new video modes a bit.
[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 }  // namespace
78
79 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
80         : httpd(LOCAL_DUMP_FILE_NAME, WIDTH, HEIGHT),
81           num_cards(num_cards),
82           mixer_surface(create_surface(format)),
83           h264_encoder_surface(create_surface(format)),
84           level_compressor(OUTPUT_FREQUENCY),
85           limiter(OUTPUT_FREQUENCY),
86           compressor(OUTPUT_FREQUENCY)
87 {
88         httpd.start(9095);
89
90         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
91         check_error();
92
93         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
94         // will be halved when sampling them, and we need to compensate here.
95         movit_texel_subpixel_precision /= 2.0;
96
97         resource_pool.reset(new ResourcePool);
98         theme.reset(new Theme("theme.lua", resource_pool.get(), num_cards));
99         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
100                 output_channel[i].parent = this;
101         }
102
103         ImageFormat inout_format;
104         inout_format.color_space = COLORSPACE_sRGB;
105         inout_format.gamma_curve = GAMMA_sRGB;
106
107         // Display chain; shows the live output produced by the main chain (its RGBA version).
108         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
109         check_error();
110         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
111         display_chain->add_input(display_input);
112         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
113         display_chain->set_dither_bits(0);  // Don't bother.
114         display_chain->finalize();
115
116         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
117
118         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
119                 printf("Configuring card %d...\n", card_index);
120                 CaptureCard *card = &cards[card_index];
121                 card->usb = new BMUSBCapture(card_index);
122                 card->usb->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
123                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
124                 card->usb->set_video_frame_allocator(card->frame_allocator.get());
125                 card->surface = create_surface(format);
126                 card->usb->set_dequeue_thread_callbacks(
127                         [card]{
128                                 eglBindAPI(EGL_OPENGL_API);
129                                 card->context = create_context(card->surface);
130                                 if (!make_current(card->context, card->surface)) {
131                                         printf("failed to create bmusb context\n");
132                                         exit(1);
133                                 }
134                         },
135                         [this]{
136                                 resource_pool->clean_context();
137                         });
138                 card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
139                 card->usb->configure_card();
140         }
141
142         BMUSBCapture::start_bm_thread();
143
144         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
145                 cards[card_index].usb->start_bm_capture();
146         }
147
148         // Set up stuff for NV12 conversion.
149
150         // Cb/Cr shader.
151         string cbcr_vert_shader = read_file("vs-cbcr.130.vert");
152         string cbcr_frag_shader =
153                 "#version 130 \n"
154                 "in vec2 tc0; \n"
155                 "uniform sampler2D cbcr_tex; \n"
156                 "void main() { \n"
157                 "    gl_FragColor = texture2D(cbcr_tex, tc0); \n"
158                 "} \n";
159         vector<string> frag_shader_outputs;
160         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
161
162         r128.init(2, OUTPUT_FREQUENCY);
163         r128.integr_start();
164
165         locut.init(FILTER_HPF, 2);
166
167         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
168         // and there's a limit to how important the peak meter is.
169         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16);
170
171         alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
172 }
173
174 Mixer::~Mixer()
175 {
176         resource_pool->release_glsl_program(cbcr_program_num);
177         BMUSBCapture::stop_bm_thread();
178
179         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
180                 {
181                         unique_lock<mutex> lock(bmusb_mutex);
182                         cards[card_index].should_quit = true;  // Unblock thread.
183                         cards[card_index].new_data_ready_changed.notify_all();
184                 }
185                 cards[card_index].usb->stop_dequeue_thread();
186         }
187
188         h264_encoder.reset(nullptr);
189 }
190
191 namespace {
192
193 int unwrap_timecode(uint16_t current_wrapped, int last)
194 {
195         uint16_t last_wrapped = last & 0xffff;
196         if (current_wrapped > last_wrapped) {
197                 return (last & ~0xffff) | current_wrapped;
198         } else {
199                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
200         }
201 }
202
203 float find_peak(const float *samples, size_t num_samples)
204 {
205         float m = fabs(samples[0]);
206         for (size_t i = 1; i < num_samples; ++i) {
207                 m = std::max(m, fabs(samples[i]));
208         }
209         return m;
210 }
211
212 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
213 {
214         size_t num_samples = in.size() / 2;
215         out_l->resize(num_samples);
216         out_r->resize(num_samples);
217
218         const float *inptr = in.data();
219         float *lptr = &(*out_l)[0];
220         float *rptr = &(*out_r)[0];
221         for (size_t i = 0; i < num_samples; ++i) {
222                 *lptr++ = *inptr++;
223                 *rptr++ = *inptr++;
224         }
225 }
226
227 }  // namespace
228
229 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
230                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
231                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
232 {
233         CaptureCard *card = &cards[card_index];
234
235         unsigned width, height, second_field_start, frame_rate_nom, frame_rate_den, extra_lines_top, extra_lines_bottom;
236         bool interlaced;
237
238         decode_video_format(video_format, &width, &height, &second_field_start, &extra_lines_top, &extra_lines_bottom,
239                             &frame_rate_nom, &frame_rate_den, &interlaced);  // Ignore return value for now.
240         int64_t frame_length = TIMEBASE * frame_rate_den / frame_rate_nom;
241
242         size_t num_samples = (audio_frame.len >= audio_offset) ? (audio_frame.len - audio_offset) / 8 / 3 : 0;
243         if (num_samples > OUTPUT_FREQUENCY / 10) {
244                 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",
245                         card_index, int(audio_frame.len), int(audio_offset),
246                         timecode, int(video_frame.len), int(video_offset), video_format);
247                 if (video_frame.owner) {
248                         video_frame.owner->release_frame(video_frame);
249                 }
250                 if (audio_frame.owner) {
251                         audio_frame.owner->release_frame(audio_frame);
252                 }
253                 return;
254         }
255
256         int64_t local_pts = card->next_local_pts;
257         int dropped_frames = 0;
258         if (card->last_timecode != -1) {
259                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
260         }
261
262         // Convert the audio to stereo fp32 and add it.
263         vector<float> audio;
264         audio.resize(num_samples * 2);
265         convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
266
267         // Add the audio.
268         {
269                 unique_lock<mutex> lock(card->audio_mutex);
270
271                 // Number of samples per frame if we need to insert silence.
272                 // (Could be nonintegral, but resampling will save us then.)
273                 int silence_samples = OUTPUT_FREQUENCY * frame_rate_den / frame_rate_nom;
274
275                 if (dropped_frames > MAX_FPS * 2) {
276                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
277                                 card_index, card->last_timecode, timecode);
278                         card->resampling_queue.reset(new ResamplingQueue(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY, 2));
279                         dropped_frames = 0;
280                 } else if (dropped_frames > 0) {
281                         // Insert silence as needed.
282                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
283                                 card_index, dropped_frames, timecode);
284                         vector<float> silence(silence_samples * 2, 0.0f);
285                         for (int i = 0; i < dropped_frames; ++i) {
286                                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), silence.data(), silence_samples);
287                                 // Note that if the format changed in the meantime, we have
288                                 // no way of detecting that; we just have to assume the frame length
289                                 // is always the same.
290                                 local_pts += frame_length;
291                         }
292                 }
293                 if (num_samples == 0) {
294                         audio.resize(silence_samples * 2);
295                         num_samples = silence_samples;
296                 }
297                 card->resampling_queue->add_input_samples(local_pts / double(TIMEBASE), audio.data(), num_samples);
298                 card->next_local_pts = local_pts + frame_length;
299         }
300
301         card->last_timecode = timecode;
302
303         // Done with the audio, so release it.
304         if (audio_frame.owner) {
305                 audio_frame.owner->release_frame(audio_frame);
306         }
307
308         {
309                 // Wait until the previous frame was consumed.
310                 unique_lock<mutex> lock(bmusb_mutex);
311                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
312                 if (card->should_quit) return;
313         }
314
315         size_t expected_length = width * (height + extra_lines_top + extra_lines_bottom) * 2;
316         if (video_frame.len - video_offset == 0 ||
317             video_frame.len - video_offset != expected_length) {
318                 if (video_frame.len != 0) {
319                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
320                                 card_index, video_frame.len - video_offset, expected_length);
321                 }
322                 if (video_frame.owner) {
323                         video_frame.owner->release_frame(video_frame);
324                 }
325
326                 // Still send on the information that we _had_ a frame, even though it's corrupted,
327                 // so that pts can go up accordingly.
328                 {
329                         unique_lock<mutex> lock(bmusb_mutex);
330                         card->new_data_ready = true;
331                         card->new_frame = RefCountedFrame(FrameAllocator::Frame());
332                         card->new_frame_length = frame_length;
333                         card->new_frame_interlaced = false;
334                         card->new_data_ready_fence = nullptr;
335                         card->dropped_frames = dropped_frames;
336                         card->new_data_ready_changed.notify_all();
337                 }
338                 return;
339         }
340
341         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
342
343         unsigned num_fields = interlaced ? 2 : 1;
344         timespec frame_upload_start;
345         if (interlaced) {
346                 // Send the two fields along as separate frames; the other side will need to add
347                 // a deinterlacer to actually get this right.
348                 assert(height % 2 == 0);
349                 height /= 2;
350                 assert(frame_length % 2 == 0);
351                 frame_length /= 2;
352                 num_fields = 2;
353                 clock_gettime(CLOCK_MONOTONIC, &frame_upload_start);
354         }
355         userdata->last_interlaced = interlaced;
356         RefCountedFrame new_frame(video_frame);
357
358         // Upload the textures.
359         size_t cbcr_width = width / 2;
360         size_t cbcr_offset = video_offset / 2;
361         size_t y_offset = video_frame.size / 2 + video_offset / 2;
362
363         for (unsigned field = 0; field < num_fields; ++field) {
364                 unsigned field_start_line = (field == 1) ? second_field_start : extra_lines_top + field * (height + 22);
365
366                 if (userdata->tex_y[field] == 0 ||
367                     userdata->tex_cbcr[field] == 0 ||
368                     width != userdata->last_width[field] ||
369                     height != userdata->last_height[field]) {
370                         // We changed resolution since last use of this texture, so we need to create
371                         // a new object. Note that this each card has its own PBOFrameAllocator,
372                         // we don't need to worry about these flip-flopping between resolutions.
373                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
374                         check_error();
375                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
376                         check_error();
377                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
378                         check_error();
379                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
380                         check_error();
381                         userdata->last_width[field] = width;
382                         userdata->last_height[field] = height;
383                 }
384
385                 GLuint pbo = userdata->pbo;
386                 check_error();
387                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
388                 check_error();
389                 glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
390                 check_error();
391
392                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
393                 check_error();
394                 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)));
395                 check_error();
396                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
397                 check_error();
398                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(y_offset + width * field_start_line));
399                 check_error();
400                 glBindTexture(GL_TEXTURE_2D, 0);
401                 check_error();
402                 GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
403                 check_error();
404                 assert(fence != nullptr);
405
406                 if (field == 1) {
407                         // Don't upload the second field as fast as we can; wait until
408                         // the field time has approximately passed. (Otherwise, we could
409                         // get timing jitter against the other sources, and possibly also
410                         // against the video display, although the latter is not as critical.)
411                         // This requires our system clock to be reasonably close to the
412                         // video clock, but that's not an unreasonable assumption.
413                         timespec second_field_start;
414                         second_field_start.tv_nsec = frame_upload_start.tv_nsec +
415                                 frame_length * 1000000000 / TIMEBASE;
416                         second_field_start.tv_sec = frame_upload_start.tv_sec +
417                                 second_field_start.tv_nsec / 1000000000;
418                         second_field_start.tv_nsec %= 1000000000;
419
420                         while (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
421                                                &second_field_start, nullptr) == -1 &&
422                                errno == EINTR) ;
423                 }
424
425                 {
426                         unique_lock<mutex> lock(bmusb_mutex);
427                         card->new_data_ready = true;
428                         card->new_frame = new_frame;
429                         card->new_frame_length = frame_length;
430                         card->new_frame_field = field;
431                         card->new_frame_interlaced = interlaced;
432                         card->new_data_ready_fence = fence;
433                         card->dropped_frames = dropped_frames;
434                         card->new_data_ready_changed.notify_all();
435
436                         if (field != num_fields - 1) {
437                                 // Wait until the previous frame was consumed.
438                                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
439                                 if (card->should_quit) return;
440                         }
441                 }
442         }
443 }
444
445 void Mixer::thread_func()
446 {
447         eglBindAPI(EGL_OPENGL_API);
448         QOpenGLContext *context = create_context(mixer_surface);
449         if (!make_current(context, mixer_surface)) {
450                 printf("oops\n");
451                 exit(1);
452         }
453
454         struct timespec start, now;
455         clock_gettime(CLOCK_MONOTONIC, &start);
456
457         int frame = 0;
458         int stats_dropped_frames = 0;
459
460         while (!should_quit) {
461                 CaptureCard card_copy[MAX_CARDS];
462                 int num_samples[MAX_CARDS];
463
464                 {
465                         unique_lock<mutex> lock(bmusb_mutex);
466
467                         // The first card is the master timer, so wait for it to have a new frame.
468                         // TODO: Make configurable, and with a timeout.
469                         cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
470
471                         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
472                                 CaptureCard *card = &cards[card_index];
473                                 card_copy[card_index].usb = card->usb;
474                                 card_copy[card_index].new_data_ready = card->new_data_ready;
475                                 card_copy[card_index].new_frame = card->new_frame;
476                                 card_copy[card_index].new_frame_length = card->new_frame_length;
477                                 card_copy[card_index].new_frame_field = card->new_frame_field;
478                                 card_copy[card_index].new_frame_interlaced = card->new_frame_interlaced;
479                                 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
480                                 card_copy[card_index].dropped_frames = card->dropped_frames;
481                                 card->new_data_ready = false;
482                                 card->new_data_ready_changed.notify_all();
483
484                                 int num_samples_times_timebase = OUTPUT_FREQUENCY * card->new_frame_length + card->fractional_samples;
485                                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
486                                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
487                                 assert(num_samples[card_index] >= 0);
488                         }
489                 }
490
491                 // Resample the audio as needed, including from previously dropped frames.
492                 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
493                         {
494                                 // Signal to the audio thread to process this frame.
495                                 unique_lock<mutex> lock(audio_mutex);
496                                 audio_task_queue.push(AudioTask{pts_int, num_samples[0]});
497                                 audio_task_queue_changed.notify_one();
498                         }
499                         if (frame_num != card_copy[0].dropped_frames) {
500                                 // For dropped frames, increase the pts. Note that if the format changed
501                                 // in the meantime, we have no way of detecting that; we just have to
502                                 // assume the frame length is always the same.
503                                 ++stats_dropped_frames;
504                                 pts_int += card_copy[0].new_frame_length;
505                         }
506                 }
507
508                 if (audio_level_callback != nullptr) {
509                         unique_lock<mutex> lock(r128_mutex);
510                         double loudness_s = r128.loudness_S();
511                         double loudness_i = r128.integrated();
512                         double loudness_range_low = r128.range_min();
513                         double loudness_range_high = r128.range_max();
514
515                         audio_level_callback(loudness_s, 20.0 * log10(peak),
516                                              loudness_i, loudness_range_low, loudness_range_high,
517                                              last_gain_staging_db);
518                 }
519
520                 for (unsigned card_index = 1; card_index < num_cards; ++card_index) {
521                         if (card_copy[card_index].new_data_ready && card_copy[card_index].new_frame->len == 0) {
522                                 ++card_copy[card_index].dropped_frames;
523                         }
524                         if (card_copy[card_index].dropped_frames > 0) {
525                                 printf("Card %u dropped %d frames before this\n",
526                                         card_index, int(card_copy[card_index].dropped_frames));
527                         }
528                 }
529
530                 // If the first card is reporting a corrupted or otherwise dropped frame,
531                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
532                 if (card_copy[0].new_frame->len == 0) {
533                         ++stats_dropped_frames;
534                         pts_int += card_copy[0].new_frame_length;
535                         continue;
536                 }
537
538                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
539                         CaptureCard *card = &card_copy[card_index];
540                         if (!card->new_data_ready || card->new_frame->len == 0)
541                                 continue;
542
543                         assert(card->new_frame != nullptr);
544                         insert_new_frame(card->new_frame, card->new_frame_field, card->new_frame_interlaced, card_index, &input_state);
545                         check_error();
546
547                         // The new texture might still be uploaded,
548                         // tell the GPU to wait until it's there.
549                         if (card->new_data_ready_fence) {
550                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
551                                 check_error();
552                                 glDeleteSync(card->new_data_ready_fence);
553                                 check_error();
554                         }
555                 }
556
557                 // Get the main chain from the theme, and set its state immediately.
558                 Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
559                 EffectChain *chain = theme_main_chain.chain;
560                 theme_main_chain.setup_chain();
561                 //theme_main_chain.chain->enable_phase_timing(true);
562
563                 GLuint y_tex, cbcr_tex;
564                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
565                 assert(got_frame);
566
567                 // Render main chain.
568                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
569                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
570                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
571                 check_error();
572                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
573                 resource_pool->release_fbo(fbo);
574
575                 subsample_chroma(cbcr_full_tex, cbcr_tex);
576                 resource_pool->release_2d_texture(cbcr_full_tex);
577
578                 // Set the right state for rgba_tex.
579                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
580                 glBindTexture(GL_TEXTURE_2D, rgba_tex);
581                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
582                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
583                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
584
585                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
586                 check_error();
587
588                 const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
589                 h264_encoder->end_frame(fence, pts_int + av_delay, theme_main_chain.input_frames);
590                 ++frame;
591                 pts_int += card_copy[0].new_frame_length;
592
593                 // The live frame just shows the RGBA texture we just rendered.
594                 // It owns rgba_tex now.
595                 DisplayFrame live_frame;
596                 live_frame.chain = display_chain.get();
597                 live_frame.setup_chain = [this, rgba_tex]{
598                         display_input->set_texture_num(rgba_tex);
599                 };
600                 live_frame.ready_fence = fence;
601                 live_frame.input_frames = {};
602                 live_frame.temp_textures = { rgba_tex };
603                 output_channel[OUTPUT_LIVE].output_frame(live_frame);
604
605                 // Set up preview and any additional channels.
606                 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
607                         DisplayFrame display_frame;
608                         Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
609                         display_frame.chain = chain.chain;
610                         display_frame.setup_chain = chain.setup_chain;
611                         display_frame.ready_fence = fence;
612                         display_frame.input_frames = chain.input_frames;
613                         display_frame.temp_textures = {};
614                         output_channel[i].output_frame(display_frame);
615                 }
616
617                 clock_gettime(CLOCK_MONOTONIC, &now);
618                 double elapsed = now.tv_sec - start.tv_sec +
619                         1e-9 * (now.tv_nsec - start.tv_nsec);
620                 if (frame % 100 == 0) {
621                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
622                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
623                                 1e3 * elapsed / frame);
624                 //      chain->print_phase_timing();
625                 }
626
627 #if 0
628                 // Reset every 100 frames, so that local variations in frame times
629                 // (especially for the first few frames, when the shaders are
630                 // compiled etc.) don't make it hard to measure for the entire
631                 // remaining duration of the program.
632                 if (frame == 10000) {
633                         frame = 0;
634                         start = now;
635                 }
636 #endif
637                 check_error();
638         }
639
640         resource_pool->clean_context();
641 }
642
643 void Mixer::audio_thread_func()
644 {
645         while (!should_quit) {
646                 AudioTask task;
647
648                 {
649                         unique_lock<mutex> lock(audio_mutex);
650                         audio_task_queue_changed.wait(lock, [this]{ return !audio_task_queue.empty(); });
651                         task = audio_task_queue.front();
652                         audio_task_queue.pop();
653                 }
654
655                 process_audio_one_frame(task.pts_int, task.num_samples);
656         }
657 }
658
659 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples)
660 {
661         vector<float> samples_card;
662         vector<float> samples_out;
663         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
664                 samples_card.resize(num_samples * 2);
665                 {
666                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
667                         if (!cards[card_index].resampling_queue->get_output_samples(double(frame_pts_int) / TIMEBASE, &samples_card[0], num_samples)) {
668                                 printf("Card %d reported previous underrun.\n", card_index);
669                         }
670                 }
671                 // TODO: Allow using audio from the other card(s) as well.
672                 if (card_index == 0) {
673                         samples_out = move(samples_card);
674                 }
675         }
676
677         // Cut away everything under 120 Hz (or whatever the cutoff is);
678         // we don't need it for voice, and it will reduce headroom
679         // and confuse the compressor. (In particular, any hums at 50 or 60 Hz
680         // should be dampened.)
681         locut.render(samples_out.data(), samples_out.size() / 2, locut_cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f);
682
683         // Apply a level compressor to get the general level right.
684         // Basically, if it's over about -40 dBFS, we squeeze it down to that level
685         // (or more precisely, near it, since we don't use infinite ratio),
686         // then apply a makeup gain to get it to -14 dBFS. -14 dBFS is, of course,
687         // entirely arbitrary, but from practical tests with speech, it seems to
688         // put ut around -23 LUFS, so it's a reasonable starting point for later use.
689         float ref_level_dbfs = -14.0f;
690         {
691                 float threshold = 0.01f;   // -40 dBFS.
692                 float ratio = 20.0f;
693                 float attack_time = 0.5f;
694                 float release_time = 20.0f;
695                 float makeup_gain = pow(10.0f, (ref_level_dbfs - (-40.0f)) / 20.0f);  // +26 dB.
696                 level_compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
697                 last_gain_staging_db = 20.0 * log10(level_compressor.get_attenuation() * makeup_gain);
698         }
699
700 #if 0
701         printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
702                 level_compressor.get_level(), 20.0 * log10(level_compressor.get_level()),
703                 level_compressor.get_attenuation(), 20.0 * log10(level_compressor.get_attenuation()),
704                 20.0 * log10(level_compressor.get_level() * level_compressor.get_attenuation() * makeup_gain));
705 #endif
706
707 //      float limiter_att, compressor_att;
708
709         // The real compressor.
710         if (compressor_enabled) {
711                 float threshold = pow(10.0f, compressor_threshold_dbfs / 20.0f);
712                 float ratio = 20.0f;
713                 float attack_time = 0.005f;
714                 float release_time = 0.040f;
715                 float makeup_gain = 2.0f;  // +6 dB.
716                 compressor.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
717 //              compressor_att = compressor.get_attenuation();
718         }
719
720         // Finally a limiter at -4 dB (so, -10 dBFS) to take out the worst peaks only.
721         // Note that since ratio is not infinite, we could go slightly higher than this.
722         if (limiter_enabled) {
723                 float threshold = pow(10.0f, limiter_threshold_dbfs / 20.0f);
724                 float ratio = 30.0f;
725                 float attack_time = 0.0f;  // Instant.
726                 float release_time = 0.020f;
727                 float makeup_gain = 1.0f;  // 0 dB.
728                 limiter.process(samples_out.data(), samples_out.size() / 2, threshold, ratio, attack_time, release_time, makeup_gain);
729 //              limiter_att = limiter.get_attenuation();
730         }
731
732 //      printf("limiter=%+5.1f  compressor=%+5.1f\n", 20.0*log10(limiter_att), 20.0*log10(compressor_att));
733
734         // Upsample 4x to find interpolated peak.
735         peak_resampler.inp_data = samples_out.data();
736         peak_resampler.inp_count = samples_out.size() / 2;
737
738         vector<float> interpolated_samples_out;
739         interpolated_samples_out.resize(samples_out.size());
740         while (peak_resampler.inp_count > 0) {  // About four iterations.
741                 peak_resampler.out_data = &interpolated_samples_out[0];
742                 peak_resampler.out_count = interpolated_samples_out.size() / 2;
743                 peak_resampler.process();
744                 size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
745                 peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
746         }
747
748         // Find R128 levels.
749         vector<float> left, right;
750         deinterleave_samples(samples_out, &left, &right);
751         float *ptrs[] = { left.data(), right.data() };
752         {
753                 unique_lock<mutex> lock(r128_mutex);
754                 r128.process(left.size(), ptrs);
755         }
756
757         // Send the samples to the sound card.
758         if (alsa) {
759                 alsa->write(samples_out);
760         }
761
762         // And finally add them to the output.
763         h264_encoder->add_audio(frame_pts_int, move(samples_out));
764 }
765
766 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
767 {
768         GLuint vao;
769         glGenVertexArrays(1, &vao);
770         check_error();
771
772         float vertices[] = {
773                 0.0f, 2.0f,
774                 0.0f, 0.0f,
775                 2.0f, 0.0f
776         };
777
778         glBindVertexArray(vao);
779         check_error();
780
781         // Extract Cb/Cr.
782         GLuint fbo = resource_pool->create_fbo(dst_tex);
783         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
784         glViewport(0, 0, WIDTH/2, HEIGHT/2);
785         check_error();
786
787         glUseProgram(cbcr_program_num);
788         check_error();
789
790         glActiveTexture(GL_TEXTURE0);
791         check_error();
792         glBindTexture(GL_TEXTURE_2D, src_tex);
793         check_error();
794         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
795         check_error();
796         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
797         check_error();
798         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
799         check_error();
800
801         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
802         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
803
804         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
805         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
806
807         glDrawArrays(GL_TRIANGLES, 0, 3);
808         check_error();
809
810         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
811         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
812
813         glUseProgram(0);
814         check_error();
815
816         resource_pool->release_fbo(fbo);
817         glDeleteVertexArrays(1, &vao);
818 }
819
820 void Mixer::release_display_frame(DisplayFrame *frame)
821 {
822         for (GLuint texnum : frame->temp_textures) {
823                 resource_pool->release_2d_texture(texnum);
824         }
825         frame->temp_textures.clear();
826         frame->ready_fence.reset();
827         frame->input_frames.clear();
828 }
829
830 void Mixer::start()
831 {
832         mixer_thread = thread(&Mixer::thread_func, this);
833         audio_thread = thread(&Mixer::audio_thread_func, this);
834 }
835
836 void Mixer::quit()
837 {
838         should_quit = true;
839         mixer_thread.join();
840         audio_thread.join();
841 }
842
843 void Mixer::transition_clicked(int transition_num)
844 {
845         theme->transition_clicked(transition_num, pts());
846 }
847
848 void Mixer::channel_clicked(int preview_num)
849 {
850         theme->channel_clicked(preview_num);
851 }
852
853 void Mixer::reset_meters()
854 {
855         peak_resampler.reset();
856         peak = 0.0f;
857         r128.reset();
858         r128.integr_start();
859 }
860
861 Mixer::OutputChannel::~OutputChannel()
862 {
863         if (has_current_frame) {
864                 parent->release_display_frame(&current_frame);
865         }
866         if (has_ready_frame) {
867                 parent->release_display_frame(&ready_frame);
868         }
869 }
870
871 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
872 {
873         // Store this frame for display. Remove the ready frame if any
874         // (it was seemingly never used).
875         {
876                 unique_lock<mutex> lock(frame_mutex);
877                 if (has_ready_frame) {
878                         parent->release_display_frame(&ready_frame);
879                 }
880                 ready_frame = frame;
881                 has_ready_frame = true;
882         }
883
884         if (has_new_frame_ready_callback) {
885                 new_frame_ready_callback();
886         }
887 }
888
889 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
890 {
891         unique_lock<mutex> lock(frame_mutex);
892         if (!has_current_frame && !has_ready_frame) {
893                 return false;
894         }
895
896         if (has_current_frame && has_ready_frame) {
897                 // We have a new ready frame. Toss the current one.
898                 parent->release_display_frame(&current_frame);
899                 has_current_frame = false;
900         }
901         if (has_ready_frame) {
902                 assert(!has_current_frame);
903                 current_frame = ready_frame;
904                 ready_frame.ready_fence.reset();  // Drop the refcount.
905                 ready_frame.input_frames.clear();  // Drop the refcounts.
906                 has_current_frame = true;
907                 has_ready_frame = false;
908         }
909
910         *frame = current_frame;
911         return true;
912 }
913
914 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
915 {
916         new_frame_ready_callback = callback;
917         has_new_frame_ready_callback = true;
918 }