]> git.sesse.net Git - nageru/blob - mixer.cpp
Display a copy of the Y'CbCr images instead of an RGB565 copy.
[nageru] / mixer.cpp
1 #undef Success
2
3 #include "mixer.h"
4
5 #include <assert.h>
6 #include <epoxy/egl.h>
7 #include <movit/effect_chain.h>
8 #include <movit/effect_util.h>
9 #include <movit/flat_input.h>
10 #include <movit/image_format.h>
11 #include <movit/init.h>
12 #include <movit/resource_pool.h>
13 #include <pthread.h>
14 #include <stdint.h>
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <sys/resource.h>
18 #include <algorithm>
19 #include <chrono>
20 #include <condition_variable>
21 #include <cstddef>
22 #include <cstdint>
23 #include <memory>
24 #include <mutex>
25 #include <ratio>
26 #include <string>
27 #include <thread>
28 #include <utility>
29 #include <vector>
30
31 #include "DeckLinkAPI.h"
32 #include "LinuxCOM.h"
33 #include "alsa_output.h"
34 #include "bmusb/bmusb.h"
35 #include "bmusb/fake_capture.h"
36 #include "chroma_subsampler.h"
37 #include "context.h"
38 #include "decklink_capture.h"
39 #include "decklink_output.h"
40 #include "defs.h"
41 #include "disk_space_estimator.h"
42 #include "flags.h"
43 #include "input_mapping.h"
44 #include "pbo_frame_allocator.h"
45 #include "ref_counted_gl_sync.h"
46 #include "resampling_queue.h"
47 #include "timebase.h"
48 #include "timecode_renderer.h"
49 #include "v210_converter.h"
50 #include "video_encoder.h"
51
52 class IDeckLink;
53 class QOpenGLContext;
54
55 using namespace movit;
56 using namespace std;
57 using namespace std::chrono;
58 using namespace std::placeholders;
59 using namespace bmusb;
60
61 Mixer *global_mixer = nullptr;
62 bool uses_mlock = false;
63
64 namespace {
65
66 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
67 {
68         if (interlaced) {
69                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
70                         input_state->buffered_frames[card_index][frame_num] =
71                                 input_state->buffered_frames[card_index][frame_num - 1];
72                 }
73                 input_state->buffered_frames[card_index][0] = { frame, field_num };
74         } else {
75                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
76                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
77                 }
78         }
79 }
80
81 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned v210_width)
82 {
83         bool first;
84         if (global_flags.ten_bit_input) {
85                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
86         } else {
87                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
88         }
89
90         if (first ||
91             width != userdata->last_width[field] ||
92             height != userdata->last_height[field]) {
93                 // We changed resolution since last use of this texture, so we need to create
94                 // a new object. Note that this each card has its own PBOFrameAllocator,
95                 // we don't need to worry about these flip-flopping between resolutions.
96                 if (global_flags.ten_bit_input) {
97                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
98                         check_error();
99                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
100                         check_error();
101                 } else {
102                         size_t cbcr_width = width / 2;
103
104                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
105                         check_error();
106                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
107                         check_error();
108                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
109                         check_error();
110                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
111                         check_error();
112                 }
113                 userdata->last_width[field] = width;
114                 userdata->last_height[field] = height;
115         }
116         if (global_flags.ten_bit_input &&
117             (first || v210_width != userdata->last_v210_width[field])) {
118                 // Same as above; we need to recreate the texture.
119                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
120                 check_error();
121                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
122                 check_error();
123                 userdata->last_v210_width[field] = v210_width;
124         }
125 }
126
127 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
128 {
129         if (interlaced_stride) {
130                 stride *= 2;
131         }
132         if (global_flags.flush_pbos) {
133                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
134                 check_error();
135         }
136
137         glBindTexture(GL_TEXTURE_2D, tex);
138         check_error();
139         if (interlaced_stride) {
140                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
141                 check_error();
142         } else {
143                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
144                 check_error();
145         }
146
147         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
148         check_error();
149         glBindTexture(GL_TEXTURE_2D, 0);
150         check_error();
151         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
152         check_error();
153 }
154
155 }  // namespace
156
157 void QueueLengthPolicy::update_policy(unsigned queue_length)
158 {
159         if (queue_length == 0) {  // Starvation.
160                 if (been_at_safe_point_since_last_starvation && safe_queue_length < unsigned(global_flags.max_input_queue_frames)) {
161                         ++safe_queue_length;
162                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frame(s)\n",
163                                 card_index, safe_queue_length);
164                 }
165                 frames_with_at_least_one = 0;
166                 been_at_safe_point_since_last_starvation = false;
167                 return;
168         }
169         if (queue_length >= safe_queue_length) {
170                 been_at_safe_point_since_last_starvation = true;
171         }
172         if (++frames_with_at_least_one >= 1000 && safe_queue_length > 1) {
173                 --safe_queue_length;
174                 fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frame(s)\n",
175                         card_index, safe_queue_length);
176                 frames_with_at_least_one = 0;
177         }
178 }
179
180 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
181         : httpd(),
182           num_cards(num_cards),
183           mixer_surface(create_surface(format)),
184           h264_encoder_surface(create_surface(format)),
185           decklink_output_surface(create_surface(format)),
186           audio_mixer(num_cards)
187 {
188         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
189         check_error();
190
191         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
192         // will be halved when sampling them, and we need to compensate here.
193         movit_texel_subpixel_precision /= 2.0;
194
195         resource_pool.reset(new ResourcePool);
196         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
197         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
198                 output_channel[i].parent = this;
199                 output_channel[i].channel = i;
200         }
201
202         ImageFormat inout_format;
203         inout_format.color_space = COLORSPACE_sRGB;
204         inout_format.gamma_curve = GAMMA_sRGB;
205
206         // Matches the 4:2:0 format created by the main chain.
207         YCbCrFormat ycbcr_format;
208         ycbcr_format.chroma_subsampling_x = 2;
209         ycbcr_format.chroma_subsampling_y = 2;
210         if (global_flags.ycbcr_rec709_coefficients) {
211                 ycbcr_format.luma_coefficients = YCBCR_REC_709;
212         } else {
213                 ycbcr_format.luma_coefficients = YCBCR_REC_601;
214         }
215         ycbcr_format.full_range = false;
216         ycbcr_format.num_levels = 256;
217         ycbcr_format.cb_x_position = 0.0f;
218         ycbcr_format.cr_x_position = 0.0f;
219         ycbcr_format.cb_y_position = 0.5f;
220         ycbcr_format.cr_y_position = 0.5f;
221
222         // Display chain; shows the live output produced by the main chain (or rather, a copy of it).
223         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
224         check_error();
225         display_input = new YCbCrInput(inout_format, ycbcr_format, global_flags.width, global_flags.height, YCBCR_INPUT_SPLIT_Y_AND_CBCR);
226         display_chain->add_input(display_input);
227         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
228         display_chain->set_dither_bits(0);  // Don't bother.
229         display_chain->finalize();
230
231         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, global_flags.width, global_flags.height, &httpd, global_disk_space_estimator));
232
233         // Start listening for clients only once VideoEncoder has written its header, if any.
234         httpd.start(9095);
235
236         // First try initializing the then PCI devices, then USB, then
237         // fill up with fake cards until we have the desired number of cards.
238         unsigned num_pci_devices = 0;
239         unsigned card_index = 0;
240
241         {
242                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
243                 if (decklink_iterator != nullptr) {
244                         for ( ; card_index < num_cards; ++card_index) {
245                                 IDeckLink *decklink;
246                                 if (decklink_iterator->Next(&decklink) != S_OK) {
247                                         break;
248                                 }
249
250                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
251                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
252                                 output->set_device(decklink);
253                                 configure_card(card_index, capture, /*is_fake_capture=*/false, output);
254                                 ++num_pci_devices;
255                         }
256                         decklink_iterator->Release();
257                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
258                 } else {
259                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
260                 }
261         }
262
263         unsigned num_usb_devices = BMUSBCapture::num_cards();
264         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
265                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
266                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
267                 configure_card(card_index, capture, /*is_fake_capture=*/false, /*output=*/nullptr);
268         }
269         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
270
271         unsigned num_fake_cards = 0;
272         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
273                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
274                 configure_card(card_index, capture, /*is_fake_capture=*/true, /*output=*/nullptr);
275         }
276
277         if (num_fake_cards > 0) {
278                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
279         }
280
281         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
282         BMUSBCapture::start_bm_thread();
283
284         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
285                 cards[card_index].queue_length_policy.reset(card_index);
286         }
287
288         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
289
290         if (global_flags.ten_bit_input) {
291                 if (!v210Converter::has_hardware_support()) {
292                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
293                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
294                         exit(1);
295                 }
296                 v210_converter.reset(new v210Converter());
297
298                 // These are all the widths listed in the Blackmagic SDK documentation
299                 // (section 2.7.3, “Display Modes”).
300                 v210_converter->precompile_shader(720);
301                 v210_converter->precompile_shader(1280);
302                 v210_converter->precompile_shader(1920);
303                 v210_converter->precompile_shader(2048);
304                 v210_converter->precompile_shader(3840);
305                 v210_converter->precompile_shader(4096);
306         }
307
308         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
309         display_timecode_in_stream = global_flags.display_timecode_in_stream;
310         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
311
312         if (global_flags.enable_alsa_output) {
313                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
314         }
315         if (global_flags.output_card != -1) {
316                 desired_output_card_index = global_flags.output_card;
317                 set_output_card_internal(global_flags.output_card);
318         }
319 }
320
321 Mixer::~Mixer()
322 {
323         BMUSBCapture::stop_bm_thread();
324
325         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
326                 {
327                         unique_lock<mutex> lock(card_mutex);
328                         cards[card_index].should_quit = true;  // Unblock thread.
329                         cards[card_index].new_frames_changed.notify_all();
330                 }
331                 cards[card_index].capture->stop_dequeue_thread();
332                 if (cards[card_index].output) {
333                         cards[card_index].output->end_output();
334                         cards[card_index].output.reset();
335                 }
336         }
337
338         video_encoder.reset(nullptr);
339 }
340
341 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, bool is_fake_capture, DeckLinkOutput *output)
342 {
343         printf("Configuring card %d...\n", card_index);
344
345         CaptureCard *card = &cards[card_index];
346         if (card->capture != nullptr) {
347                 card->capture->stop_dequeue_thread();
348         }
349         card->capture.reset(capture);
350         card->is_fake_capture = is_fake_capture;
351         if (card->output.get() != output) {
352                 card->output.reset(output);
353         }
354         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
355         if (card->frame_allocator == nullptr) {
356                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, global_flags.width, global_flags.height));  // 8 MB.
357         }
358         card->capture->set_video_frame_allocator(card->frame_allocator.get());
359         if (card->surface == nullptr) {
360                 card->surface = create_surface_with_same_format(mixer_surface);
361         }
362         while (!card->new_frames.empty()) card->new_frames.pop_front();
363         card->last_timecode = -1;
364         card->capture->set_pixel_format(global_flags.ten_bit_input ? PixelFormat_10BitYCbCr : PixelFormat_8BitYCbCr);
365         card->capture->configure_card();
366
367         // NOTE: start_bm_capture() happens in thread_func().
368
369         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
370         audio_mixer.reset_resampler(device);
371         audio_mixer.set_display_name(device, card->capture->get_description());
372         audio_mixer.trigger_state_changed_callback();
373 }
374
375 void Mixer::set_output_card_internal(int card_index)
376 {
377         // We don't really need to take card_mutex, since we're in the mixer
378         // thread and don't mess with any queues (which is the only thing that happens
379         // from other threads), but it's probably the safest in the long run.
380         unique_lock<mutex> lock(card_mutex);
381         if (output_card_index != -1) {
382                 // Switch the old card from output to input.
383                 CaptureCard *old_card = &cards[output_card_index];
384                 old_card->output->end_output();
385
386                 // Stop the fake card that we put into place.
387                 // This needs to _not_ happen under the mutex, to avoid deadlock
388                 // (delivering the last frame needs to take the mutex).
389                 bmusb::CaptureInterface *fake_capture = old_card->capture.get();
390                 lock.unlock();
391                 fake_capture->stop_dequeue_thread();
392                 lock.lock();
393                 old_card->capture = move(old_card->parked_capture);
394                 old_card->is_fake_capture = false;
395                 old_card->capture->start_bm_capture();
396         }
397         if (card_index != -1) {
398                 CaptureCard *card = &cards[card_index];
399                 bmusb::CaptureInterface *capture = card->capture.get();
400                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
401                 // several seconds to complete (blocking on DisableVideoInput);
402                 // see if we can maybe do it asynchronously.
403                 lock.unlock();
404                 capture->stop_dequeue_thread();
405                 lock.lock();
406                 card->parked_capture = move(card->capture);
407                 bmusb::CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
408                 configure_card(card_index, fake_capture, /*is_fake_capture=*/true, card->output.release());
409                 card->queue_length_policy.reset(card_index);
410                 card->capture->start_bm_capture();
411                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
412                 card->output->start_output(desired_output_video_mode, pts_int);
413         }
414         output_card_index = card_index;
415 }
416
417 namespace {
418
419 int unwrap_timecode(uint16_t current_wrapped, int last)
420 {
421         uint16_t last_wrapped = last & 0xffff;
422         if (current_wrapped > last_wrapped) {
423                 return (last & ~0xffff) | current_wrapped;
424         } else {
425                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
426         }
427 }
428
429 }  // namespace
430
431 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
432                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
433                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
434 {
435         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
436         CaptureCard *card = &cards[card_index];
437
438         if (is_mode_scanning[card_index]) {
439                 if (video_format.has_signal) {
440                         // Found a stable signal, so stop scanning.
441                         is_mode_scanning[card_index] = false;
442                 } else {
443                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
444                         steady_clock::time_point now = steady_clock::now();
445                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
446                         if (sec_since_last_switch > switch_time_s) {
447                                 // It isn't this mode; try the next one.
448                                 mode_scanlist_index[card_index]++;
449                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
450                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
451                                 last_mode_scan_change[card_index] = now;
452                         }
453                 }
454         }
455
456         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
457         assert(frame_length > 0);
458
459         size_t num_samples = (audio_frame.len > audio_offset) ? (audio_frame.len - audio_offset) / audio_format.num_channels / (audio_format.bits_per_sample / 8) : 0;
460         if (num_samples > OUTPUT_FREQUENCY / 10) {
461                 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",
462                         card_index, int(audio_frame.len), int(audio_offset),
463                         timecode, int(video_frame.len), int(video_offset), video_format.id);
464                 if (video_frame.owner) {
465                         video_frame.owner->release_frame(video_frame);
466                 }
467                 if (audio_frame.owner) {
468                         audio_frame.owner->release_frame(audio_frame);
469                 }
470                 return;
471         }
472
473         int dropped_frames = 0;
474         if (card->last_timecode != -1) {
475                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
476         }
477
478         // Number of samples per frame if we need to insert silence.
479         // (Could be nonintegral, but resampling will save us then.)
480         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
481
482         if (dropped_frames > MAX_FPS * 2) {
483                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
484                         card_index, card->last_timecode, timecode);
485                 audio_mixer.reset_resampler(device);
486                 dropped_frames = 0;
487         } else if (dropped_frames > 0) {
488                 // Insert silence as needed.
489                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
490                         card_index, dropped_frames, timecode);
491
492                 bool success;
493                 do {
494                         success = audio_mixer.add_silence(device, silence_samples, dropped_frames, frame_length);
495                 } while (!success);
496         }
497
498         audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
499
500         // Done with the audio, so release it.
501         if (audio_frame.owner) {
502                 audio_frame.owner->release_frame(audio_frame);
503         }
504
505         card->last_timecode = timecode;
506
507         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
508         if (video_frame.len - video_offset == 0 ||
509             video_frame.len - video_offset != expected_length) {
510                 if (video_frame.len != 0) {
511                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
512                                 card_index, video_frame.len - video_offset, expected_length);
513                 }
514                 if (video_frame.owner) {
515                         video_frame.owner->release_frame(video_frame);
516                 }
517
518                 // Still send on the information that we _had_ a frame, even though it's corrupted,
519                 // so that pts can go up accordingly.
520                 {
521                         unique_lock<mutex> lock(card_mutex);
522                         CaptureCard::NewFrame new_frame;
523                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
524                         new_frame.length = frame_length;
525                         new_frame.interlaced = false;
526                         new_frame.dropped_frames = dropped_frames;
527                         new_frame.received_timestamp = video_frame.received_timestamp;
528                         card->new_frames.push_back(move(new_frame));
529                         card->new_frames_changed.notify_all();
530                 }
531                 return;
532         }
533
534         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
535
536         unsigned num_fields = video_format.interlaced ? 2 : 1;
537         steady_clock::time_point frame_upload_start;
538         bool interlaced_stride = false;
539         if (video_format.interlaced) {
540                 // Send the two fields along as separate frames; the other side will need to add
541                 // a deinterlacer to actually get this right.
542                 assert(video_format.height % 2 == 0);
543                 video_format.height /= 2;
544                 assert(frame_length % 2 == 0);
545                 frame_length /= 2;
546                 num_fields = 2;
547                 if (video_format.second_field_start == 1) {
548                         interlaced_stride = true;
549                 }
550                 frame_upload_start = steady_clock::now();
551         }
552         userdata->last_interlaced = video_format.interlaced;
553         userdata->last_has_signal = video_format.has_signal;
554         userdata->last_is_connected = video_format.is_connected;
555         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
556         userdata->last_frame_rate_den = video_format.frame_rate_den;
557         RefCountedFrame frame(video_frame);
558
559         // Upload the textures.
560         const size_t cbcr_width = video_format.width / 2;
561         const size_t cbcr_offset = video_offset / 2;
562         const size_t y_offset = video_frame.size / 2 + video_offset / 2;
563
564         for (unsigned field = 0; field < num_fields; ++field) {
565                 // Put the actual texture upload in a lambda that is executed in the main thread.
566                 // It is entirely possible to do this in the same thread (and it might even be
567                 // faster, depending on the GPU and driver), but it appears to be trickling
568                 // driver bugs very easily.
569                 //
570                 // Note that this means we must hold on to the actual frame data in <userdata>
571                 // until the upload command is run, but we hold on to <frame> much longer than that
572                 // (in fact, all the way until we no longer use the texture in rendering).
573                 auto upload_func = [this, field, video_format, y_offset, video_offset, cbcr_offset, cbcr_width, interlaced_stride, userdata]() {
574                         unsigned field_start_line;
575                         if (field == 1) {
576                                 field_start_line = video_format.second_field_start;
577                         } else {
578                                 field_start_line = video_format.extra_lines_top;
579                         }
580
581                         // For 8-bit input, v210_width will be nonsensical but not used.
582                         size_t v210_width = video_format.stride / sizeof(uint32_t);
583                         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, v210_width);
584
585                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
586                         check_error();
587
588                         if (global_flags.ten_bit_input) {
589                                 size_t field_start = video_offset + video_format.stride * field_start_line;
590                                 upload_texture(userdata->tex_v210[field], v210_width, video_format.height, video_format.stride, interlaced_stride, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, field_start);
591                                 v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
592                         } else {
593                                 size_t field_y_start = y_offset + video_format.width * field_start_line;
594                                 size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
595
596                                 // Make up our own strides, since we are interleaving.
597                                 upload_texture(userdata->tex_y[field], video_format.width, video_format.height, video_format.width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_y_start);
598                                 upload_texture(userdata->tex_cbcr[field], cbcr_width, video_format.height, cbcr_width * sizeof(uint16_t), interlaced_stride, GL_RG, GL_UNSIGNED_BYTE, field_cbcr_start);
599                         }
600
601                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
602                         check_error();
603                 };
604
605                 if (field == 1) {
606                         // Don't upload the second field as fast as we can; wait until
607                         // the field time has approximately passed. (Otherwise, we could
608                         // get timing jitter against the other sources, and possibly also
609                         // against the video display, although the latter is not as critical.)
610                         // This requires our system clock to be reasonably close to the
611                         // video clock, but that's not an unreasonable assumption.
612                         steady_clock::time_point second_field_start = frame_upload_start +
613                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
614                         this_thread::sleep_until(second_field_start);
615                 }
616
617                 {
618                         unique_lock<mutex> lock(card_mutex);
619                         CaptureCard::NewFrame new_frame;
620                         new_frame.frame = frame;
621                         new_frame.length = frame_length;
622                         new_frame.field = field;
623                         new_frame.interlaced = video_format.interlaced;
624                         new_frame.upload_func = upload_func;
625                         new_frame.dropped_frames = dropped_frames;
626                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
627                         card->new_frames.push_back(move(new_frame));
628                         card->new_frames_changed.notify_all();
629                 }
630         }
631 }
632
633 void Mixer::bm_hotplug_add(libusb_device *dev)
634 {
635         lock_guard<mutex> lock(hotplug_mutex);
636         hotplugged_cards.push_back(dev);
637 }
638
639 void Mixer::bm_hotplug_remove(unsigned card_index)
640 {
641         cards[card_index].new_frames_changed.notify_all();
642 }
643
644 void Mixer::thread_func()
645 {
646         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
647
648         eglBindAPI(EGL_OPENGL_API);
649         QOpenGLContext *context = create_context(mixer_surface);
650         if (!make_current(context, mixer_surface)) {
651                 printf("oops\n");
652                 exit(1);
653         }
654
655         // Start the actual capture. (We don't want to do it before we're actually ready
656         // to process output frames.)
657         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
658                 if (int(card_index) != output_card_index) {
659                         cards[card_index].capture->start_bm_capture();
660                 }
661         }
662
663         steady_clock::time_point start, now;
664         start = steady_clock::now();
665
666         int stats_dropped_frames = 0;
667
668         while (!should_quit) {
669                 if (desired_output_card_index != output_card_index) {
670                         set_output_card_internal(desired_output_card_index);
671                 }
672                 if (output_card_index != -1 &&
673                     desired_output_video_mode != output_video_mode) {
674                         DeckLinkOutput *output = cards[output_card_index].output.get();
675                         output->end_output();
676                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
677                         output->start_output(desired_output_video_mode, pts_int);
678                 }
679
680                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
681                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
682
683                 bool master_card_is_output;
684                 unsigned master_card_index;
685                 if (output_card_index != -1) {
686                         master_card_is_output = true;
687                         master_card_index = output_card_index;
688                 } else {
689                         master_card_is_output = false;
690                         master_card_index = theme->map_signal(master_clock_channel);
691                         assert(master_card_index < num_cards);
692                 }
693
694                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
695                 schedule_audio_resampling_tasks(output_frame_info.dropped_frames, output_frame_info.num_samples, output_frame_info.frame_duration, output_frame_info.is_preroll, output_frame_info.frame_timestamp);
696                 stats_dropped_frames += output_frame_info.dropped_frames;
697
698                 handle_hotplugged_cards();
699
700                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
701                         if (card_index == master_card_index || !has_new_frame[card_index]) {
702                                 continue;
703                         }
704                         if (new_frames[card_index].frame->len == 0) {
705                                 ++new_frames[card_index].dropped_frames;
706                         }
707                         if (new_frames[card_index].dropped_frames > 0) {
708                                 printf("Card %u dropped %d frames before this\n",
709                                         card_index, int(new_frames[card_index].dropped_frames));
710                         }
711                 }
712
713                 // If the first card is reporting a corrupted or otherwise dropped frame,
714                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
715                 if (!master_card_is_output && new_frames[master_card_index].frame->len == 0) {
716                         ++stats_dropped_frames;
717                         pts_int += new_frames[master_card_index].length;
718                         continue;
719                 }
720
721                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
722                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
723                                 continue;
724
725                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
726                         assert(new_frame->frame != nullptr);
727                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
728                         check_error();
729
730                         // The new texture might need uploading before use.
731                         if (new_frame->upload_func) {
732                                 new_frame->upload_func();
733                                 new_frame->upload_func = nullptr;
734                         }
735                 }
736
737                 int64_t frame_duration = output_frame_info.frame_duration;
738                 render_one_frame(frame_duration);
739                 ++frame_num;
740                 pts_int += frame_duration;
741
742                 now = steady_clock::now();
743                 double elapsed = duration<double>(now - start).count();
744                 if (frame_num % 100 == 0) {
745                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
746                                 frame_num, stats_dropped_frames, elapsed, frame_num / elapsed,
747                                 1e3 * elapsed / frame_num);
748                 //      chain->print_phase_timing();
749
750                         // Check our memory usage, to see if we are close to our mlockall()
751                         // limit (if at all set).
752                         rusage used;
753                         if (getrusage(RUSAGE_SELF, &used) == -1) {
754                                 perror("getrusage(RUSAGE_SELF)");
755                                 assert(false);
756                         }
757
758                         if (uses_mlock) {
759                                 rlimit limit;
760                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
761                                         perror("getrlimit(RLIMIT_MEMLOCK)");
762                                         assert(false);
763                                 }
764
765                                 if (limit.rlim_cur == 0) {
766                                         printf(", using %ld MB memory (locked)",
767                                                 long(used.ru_maxrss / 1024));
768                                 } else {
769                                         printf(", using %ld / %ld MB lockable memory (%.1f%%)",
770                                                 long(used.ru_maxrss / 1024),
771                                                 long(limit.rlim_cur / 1048576),
772                                                 float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
773                                 }
774                         } else {
775                                 printf(", using %ld MB memory (not locked)",
776                                         long(used.ru_maxrss / 1024));
777                         }
778
779                         printf("\n");
780                 }
781
782
783                 if (should_cut.exchange(false)) {  // Test and clear.
784                         video_encoder->do_cut(frame_num);
785                 }
786
787 #if 0
788                 // Reset every 100 frames, so that local variations in frame times
789                 // (especially for the first few frames, when the shaders are
790                 // compiled etc.) don't make it hard to measure for the entire
791                 // remaining duration of the program.
792                 if (frame == 10000) {
793                         frame = 0;
794                         start = now;
795                 }
796 #endif
797                 check_error();
798         }
799
800         resource_pool->clean_context();
801 }
802
803 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
804 {
805         if (output_card_index != -1) {
806                 // The output card (ie., cards[output_card_index].output) is the master clock,
807                 // so no input card (ie., cards[card_index].capture) is.
808                 return false;
809         }
810         return (card_index == master_card_index);
811 }
812
813 void Mixer::trim_queue(CaptureCard *card, unsigned card_index)
814 {
815         // Count the number of frames in the queue, including any frames
816         // we dropped. It's hard to know exactly how we should deal with
817         // dropped (corrupted) input frames; they don't help our goal of
818         // avoiding starvation, but they still add to the problem of latency.
819         // Since dropped frames is going to mean a bump in the signal anyway,
820         // we err on the side of having more stable latency instead.
821         unsigned queue_length = 0;
822         for (const CaptureCard::NewFrame &frame : card->new_frames) {
823                 queue_length += frame.dropped_frames + 1;
824         }
825         card->queue_length_policy.update_policy(queue_length);
826
827         // If needed, drop frames until the queue is below the safe limit.
828         // We prefer to drop from the head, because all else being equal,
829         // we'd like more recent frames (less latency).
830         unsigned dropped_frames = 0;
831         while (queue_length > card->queue_length_policy.get_safe_queue_length()) {
832                 assert(!card->new_frames.empty());
833                 assert(queue_length > card->new_frames.front().dropped_frames);
834                 queue_length -= card->new_frames.front().dropped_frames;
835
836                 if (queue_length <= card->queue_length_policy.get_safe_queue_length()) {
837                         // No need to drop anything.
838                         break;
839                 }
840
841                 card->new_frames.pop_front();
842                 card->new_frames_changed.notify_all();
843                 --queue_length;
844                 ++dropped_frames;
845         }
846
847         if (dropped_frames > 0) {
848                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
849                         card_index, dropped_frames);
850         }
851 }
852
853
854 Mixer::OutputFrameInfo Mixer::get_one_frame_from_each_card(unsigned master_card_index, bool master_card_is_output, CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS], bool has_new_frame[MAX_VIDEO_CARDS])
855 {
856         OutputFrameInfo output_frame_info;
857 start:
858         unique_lock<mutex> lock(card_mutex, defer_lock);
859         if (master_card_is_output) {
860                 // Clocked to the output, so wait for it to be ready for the next frame.
861                 cards[master_card_index].output->wait_for_frame(pts_int, &output_frame_info.dropped_frames, &output_frame_info.frame_duration, &output_frame_info.is_preroll, &output_frame_info.frame_timestamp);
862                 lock.lock();
863         } else {
864                 // Wait for the master card to have a new frame.
865                 // TODO: Add a timeout.
866                 output_frame_info.is_preroll = false;
867                 lock.lock();
868                 cards[master_card_index].new_frames_changed.wait(lock, [this, master_card_index]{ return !cards[master_card_index].new_frames.empty() || cards[master_card_index].capture->get_disconnected(); });
869         }
870
871         if (master_card_is_output) {
872                 handle_hotplugged_cards();
873         } else if (cards[master_card_index].new_frames.empty()) {
874                 // We were woken up, but not due to a new frame. Deal with it
875                 // and then restart.
876                 assert(cards[master_card_index].capture->get_disconnected());
877                 handle_hotplugged_cards();
878                 goto start;
879         }
880
881         if (!master_card_is_output) {
882                 output_frame_info.frame_timestamp =
883                         cards[master_card_index].new_frames.front().received_timestamp;
884         }
885
886         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
887                 CaptureCard *card = &cards[card_index];
888                 if (input_card_is_master_clock(card_index, master_card_index)) {
889                         // We don't use the queue length policy for the master card,
890                         // but we will if it stops being the master. Thus, clear out
891                         // the policy in case we switch in the future.
892                         card->queue_length_policy.reset(card_index);
893                         assert(!card->new_frames.empty());
894                 } else {
895                         trim_queue(card, card_index);
896                 }
897                 if (!card->new_frames.empty()) {
898                         new_frames[card_index] = move(card->new_frames.front());
899                         has_new_frame[card_index] = true;
900                         card->new_frames.pop_front();
901                         card->new_frames_changed.notify_all();
902                 }
903         }
904
905         if (!master_card_is_output) {
906                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
907                 output_frame_info.frame_duration = new_frames[master_card_index].length;
908         }
909
910         // This might get off by a fractional sample when changing master card
911         // between ones with different frame rates, but that's fine.
912         int num_samples_times_timebase = OUTPUT_FREQUENCY * output_frame_info.frame_duration + fractional_samples;
913         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
914         fractional_samples = num_samples_times_timebase % TIMEBASE;
915         assert(output_frame_info.num_samples >= 0);
916
917         return output_frame_info;
918 }
919
920 void Mixer::handle_hotplugged_cards()
921 {
922         // Check for cards that have been disconnected since last frame.
923         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
924                 CaptureCard *card = &cards[card_index];
925                 if (card->capture->get_disconnected()) {
926                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
927                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
928                         configure_card(card_index, capture, /*is_fake_capture=*/true, /*output=*/nullptr);
929                         card->queue_length_policy.reset(card_index);
930                         card->capture->start_bm_capture();
931                 }
932         }
933
934         // Check for cards that have been connected since last frame.
935         vector<libusb_device *> hotplugged_cards_copy;
936         {
937                 lock_guard<mutex> lock(hotplug_mutex);
938                 swap(hotplugged_cards, hotplugged_cards_copy);
939         }
940         for (libusb_device *new_dev : hotplugged_cards_copy) {
941                 // Look for a fake capture card where we can stick this in.
942                 int free_card_index = -1;
943                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
944                         if (cards[card_index].is_fake_capture) {
945                                 free_card_index = card_index;
946                                 break;
947                         }
948                 }
949
950                 if (free_card_index == -1) {
951                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
952                         libusb_unref_device(new_dev);
953                 } else {
954                         // BMUSBCapture takes ownership.
955                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
956                         CaptureCard *card = &cards[free_card_index];
957                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
958                         configure_card(free_card_index, capture, /*is_fake_capture=*/false, /*output=*/nullptr);
959                         card->queue_length_policy.reset(free_card_index);
960                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
961                         capture->start_bm_capture();
962                 }
963         }
964 }
965
966
967 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame, bool is_preroll, steady_clock::time_point frame_timestamp)
968 {
969         // Resample the audio as needed, including from previously dropped frames.
970         assert(num_cards > 0);
971         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
972                 const bool dropped_frame = (frame_num != dropped_frames);
973                 {
974                         // Signal to the audio thread to process this frame.
975                         // Note that if the frame is a dropped frame, we signal that
976                         // we don't want to use this frame as base for adjusting
977                         // the resampler rate. The reason for this is that the timing
978                         // of these frames is often way too late; they typically don't
979                         // “arrive” before we synthesize them. Thus, we could end up
980                         // in a situation where we have inserted e.g. five audio frames
981                         // into the queue before we then start pulling five of them
982                         // back out. This makes ResamplingQueue overestimate the delay,
983                         // causing undue resampler changes. (We _do_ use the last,
984                         // non-dropped frame; perhaps we should just discard that as well,
985                         // since dropped frames are expected to be rare, and it might be
986                         // better to just wait until we have a slightly more normal situation).
987                         unique_lock<mutex> lock(audio_mutex);
988                         bool adjust_rate = !dropped_frame && !is_preroll;
989                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
990                         audio_task_queue_changed.notify_one();
991                 }
992                 if (dropped_frame) {
993                         // For dropped frames, increase the pts. Note that if the format changed
994                         // in the meantime, we have no way of detecting that; we just have to
995                         // assume the frame length is always the same.
996                         pts_int += length_per_frame;
997                 }
998         }
999 }
1000
1001 void Mixer::render_one_frame(int64_t duration)
1002 {
1003         // Determine the time code for this frame before we start rendering.
1004         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1005         if (display_timecode_on_stdout) {
1006                 printf("Timecode: '%s'\n", timecode_text.c_str());
1007         }
1008
1009         // Get the main chain from the theme, and set its state immediately.
1010         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1011         EffectChain *chain = theme_main_chain.chain;
1012         theme_main_chain.setup_chain();
1013         //theme_main_chain.chain->enable_phase_timing(true);
1014
1015         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1016         GLuint y_tex, cbcr_tex;
1017         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1018         assert(got_frame);
1019
1020         // Render main chain. We take an extra copy of the created outputs,
1021         // so that we can display it back to the screen later (it's less memory
1022         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1023         // Ideally, we'd like to avoid taking copies and just use the main textures
1024         // for display as well, but if they're used for zero-copy Quick Sync encoding
1025         // (the default case), they're just views into VA-API memory and must be
1026         // unmapped during encoding, so we can't use them for display, unfortunately.
1027         GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, global_flags.width, global_flags.height);
1028         GLuint y_copy_tex = resource_pool->create_2d_texture(GL_R8, global_flags.width, global_flags.height);
1029         GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1030         check_error();
1031         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1032
1033         if (display_timecode_in_stream) {
1034                 // Render the timecode on top.
1035                 timecode_renderer->render_timecode(fbo, timecode_text);
1036         }
1037
1038         resource_pool->release_fbo(fbo);
1039
1040         GLuint cbcr_copy_tex = resource_pool->create_2d_texture(GL_RG8, global_flags.width / 2, global_flags.height / 2);
1041         chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1042         if (output_card_index != -1) {
1043                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, theme_main_chain.input_frames, pts_int, duration);
1044         }
1045         resource_pool->release_2d_texture(cbcr_full_tex);
1046
1047         // Set the right state for the Y' and CbCr copies.
1048         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1049         glBindTexture(GL_TEXTURE_2D, y_copy_tex);
1050         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1051         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1052         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1053
1054         glBindTexture(GL_TEXTURE_2D, cbcr_copy_tex);
1055         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1056         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1057         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1058
1059         RefCountedGLsync fence = video_encoder->end_frame();
1060
1061         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1062         // It owns y_copy_tex and cbcr_copy_tex now.
1063         DisplayFrame live_frame;
1064         live_frame.chain = display_chain.get();
1065         live_frame.setup_chain = [this, y_copy_tex, cbcr_copy_tex]{
1066                 display_input->set_texture_num(0, y_copy_tex);
1067                 display_input->set_texture_num(1, cbcr_copy_tex);
1068         };
1069         live_frame.ready_fence = fence;
1070         live_frame.input_frames = {};
1071         live_frame.temp_textures = { y_copy_tex, cbcr_copy_tex };
1072         output_channel[OUTPUT_LIVE].output_frame(live_frame);
1073
1074         // Set up preview and any additional channels.
1075         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1076                 DisplayFrame display_frame;
1077                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1078                 display_frame.chain = chain.chain;
1079                 display_frame.setup_chain = chain.setup_chain;
1080                 display_frame.ready_fence = fence;
1081                 display_frame.input_frames = chain.input_frames;
1082                 display_frame.temp_textures = {};
1083                 output_channel[i].output_frame(display_frame);
1084         }
1085 }
1086
1087 void Mixer::audio_thread_func()
1088 {
1089         pthread_setname_np(pthread_self(), "Mixer_Audio");
1090
1091         while (!should_quit) {
1092                 AudioTask task;
1093
1094                 {
1095                         unique_lock<mutex> lock(audio_mutex);
1096                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1097                         if (should_quit) {
1098                                 return;
1099                         }
1100                         task = audio_task_queue.front();
1101                         audio_task_queue.pop();
1102                 }
1103
1104                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1105                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1106                 vector<float> samples_out = audio_mixer.get_output(
1107                         task.frame_timestamp,
1108                         task.num_samples,
1109                         rate_adjustment_policy);
1110
1111                 // Send the samples to the sound card, then add them to the output.
1112                 if (alsa) {
1113                         alsa->write(samples_out);
1114                 }
1115                 if (output_card_index != -1) {
1116                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1117                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1118                 }
1119                 video_encoder->add_audio(task.pts_int, move(samples_out));
1120         }
1121 }
1122
1123 void Mixer::release_display_frame(DisplayFrame *frame)
1124 {
1125         for (GLuint texnum : frame->temp_textures) {
1126                 resource_pool->release_2d_texture(texnum);
1127         }
1128         frame->temp_textures.clear();
1129         frame->ready_fence.reset();
1130         frame->input_frames.clear();
1131 }
1132
1133 void Mixer::start()
1134 {
1135         mixer_thread = thread(&Mixer::thread_func, this);
1136         audio_thread = thread(&Mixer::audio_thread_func, this);
1137 }
1138
1139 void Mixer::quit()
1140 {
1141         should_quit = true;
1142         audio_task_queue_changed.notify_one();
1143         mixer_thread.join();
1144         audio_thread.join();
1145 }
1146
1147 void Mixer::transition_clicked(int transition_num)
1148 {
1149         theme->transition_clicked(transition_num, pts());
1150 }
1151
1152 void Mixer::channel_clicked(int preview_num)
1153 {
1154         theme->channel_clicked(preview_num);
1155 }
1156
1157 void Mixer::start_mode_scanning(unsigned card_index)
1158 {
1159         assert(card_index < num_cards);
1160         if (is_mode_scanning[card_index]) {
1161                 return;
1162         }
1163         is_mode_scanning[card_index] = true;
1164         mode_scanlist[card_index].clear();
1165         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1166                 mode_scanlist[card_index].push_back(mode.first);
1167         }
1168         assert(!mode_scanlist[card_index].empty());
1169         mode_scanlist_index[card_index] = 0;
1170         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1171         last_mode_scan_change[card_index] = steady_clock::now();
1172 }
1173
1174 map<uint32_t, bmusb::VideoMode> Mixer::get_available_output_video_modes() const
1175 {
1176         assert(desired_output_card_index != -1);
1177         unique_lock<mutex> lock(card_mutex);
1178         return cards[desired_output_card_index].output->get_available_video_modes();
1179 }
1180
1181 Mixer::OutputChannel::~OutputChannel()
1182 {
1183         if (has_current_frame) {
1184                 parent->release_display_frame(&current_frame);
1185         }
1186         if (has_ready_frame) {
1187                 parent->release_display_frame(&ready_frame);
1188         }
1189 }
1190
1191 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1192 {
1193         // Store this frame for display. Remove the ready frame if any
1194         // (it was seemingly never used).
1195         {
1196                 unique_lock<mutex> lock(frame_mutex);
1197                 if (has_ready_frame) {
1198                         parent->release_display_frame(&ready_frame);
1199                 }
1200                 ready_frame = frame;
1201                 has_ready_frame = true;
1202         }
1203
1204         if (new_frame_ready_callback) {
1205                 new_frame_ready_callback();
1206         }
1207
1208         // Reduce the number of callbacks by filtering duplicates. The reason
1209         // why we bother doing this is that Qt seemingly can get into a state
1210         // where its builds up an essentially unbounded queue of signals,
1211         // consuming more and more memory, and there's no good way of collapsing
1212         // user-defined signals or limiting the length of the queue.
1213         if (transition_names_updated_callback) {
1214                 vector<string> transition_names = global_mixer->get_transition_names();
1215                 bool changed = false;
1216                 if (transition_names.size() != last_transition_names.size()) {
1217                         changed = true;
1218                 } else {
1219                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1220                                 if (transition_names[i] != last_transition_names[i]) {
1221                                         changed = true;
1222                                         break;
1223                                 }
1224                         }
1225                 }
1226                 if (changed) {
1227                         transition_names_updated_callback(transition_names);
1228                         last_transition_names = transition_names;
1229                 }
1230         }
1231         if (name_updated_callback) {
1232                 string name = global_mixer->get_channel_name(channel);
1233                 if (name != last_name) {
1234                         name_updated_callback(name);
1235                         last_name = name;
1236                 }
1237         }
1238         if (color_updated_callback) {
1239                 string color = global_mixer->get_channel_color(channel);
1240                 if (color != last_color) {
1241                         color_updated_callback(color);
1242                         last_color = color;
1243                 }
1244         }
1245 }
1246
1247 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1248 {
1249         unique_lock<mutex> lock(frame_mutex);
1250         if (!has_current_frame && !has_ready_frame) {
1251                 return false;
1252         }
1253
1254         if (has_current_frame && has_ready_frame) {
1255                 // We have a new ready frame. Toss the current one.
1256                 parent->release_display_frame(&current_frame);
1257                 has_current_frame = false;
1258         }
1259         if (has_ready_frame) {
1260                 assert(!has_current_frame);
1261                 current_frame = ready_frame;
1262                 ready_frame.ready_fence.reset();  // Drop the refcount.
1263                 ready_frame.input_frames.clear();  // Drop the refcounts.
1264                 has_current_frame = true;
1265                 has_ready_frame = false;
1266         }
1267
1268         *frame = current_frame;
1269         return true;
1270 }
1271
1272 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1273 {
1274         new_frame_ready_callback = callback;
1275 }
1276
1277 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1278 {
1279         transition_names_updated_callback = callback;
1280 }
1281
1282 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1283 {
1284         name_updated_callback = callback;
1285 }
1286
1287 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1288 {
1289         color_updated_callback = callback;
1290 }
1291
1292 mutex RefCountedGLsync::fence_lock;