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Release Nageru 1.7.2.
[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 <algorithm>
18 #include <chrono>
19 #include <condition_variable>
20 #include <cstddef>
21 #include <cstdint>
22 #include <memory>
23 #include <mutex>
24 #include <ratio>
25 #include <string>
26 #include <thread>
27 #include <utility>
28 #include <vector>
29
30 #include "DeckLinkAPI.h"
31 #include "LinuxCOM.h"
32 #include "alsa_output.h"
33 #include "basic_stats.h"
34 #include "bmusb/bmusb.h"
35 #include "bmusb/fake_capture.h"
36 #ifdef HAVE_CEF
37 #include "cef_capture.h"
38 #endif
39 #include "chroma_subsampler.h"
40 #include "context.h"
41 #include "decklink_capture.h"
42 #include "decklink_output.h"
43 #include "defs.h"
44 #include "disk_space_estimator.h"
45 #include "ffmpeg_capture.h"
46 #include "flags.h"
47 #include "input_mapping.h"
48 #include "metrics.h"
49 #include "pbo_frame_allocator.h"
50 #include "ref_counted_gl_sync.h"
51 #include "resampling_queue.h"
52 #include "timebase.h"
53 #include "timecode_renderer.h"
54 #include "v210_converter.h"
55 #include "video_encoder.h"
56
57 #undef Status
58 #include <google/protobuf/util/json_util.h>
59 #include "json.pb.h"
60
61 class IDeckLink;
62 class QOpenGLContext;
63
64 using namespace movit;
65 using namespace std;
66 using namespace std::chrono;
67 using namespace std::placeholders;
68 using namespace bmusb;
69
70 Mixer *global_mixer = nullptr;
71
72 namespace {
73
74 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
75 {
76         if (interlaced) {
77                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
78                         input_state->buffered_frames[card_index][frame_num] =
79                                 input_state->buffered_frames[card_index][frame_num - 1];
80                 }
81                 input_state->buffered_frames[card_index][0] = { frame, field_num };
82         } else {
83                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
84                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
85                 }
86         }
87 }
88
89 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned cbcr_width, unsigned cbcr_height, unsigned v210_width)
90 {
91         bool first;
92         switch (userdata->pixel_format) {
93         case PixelFormat_10BitYCbCr:
94                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
95                 break;
96         case PixelFormat_8BitYCbCr:
97                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
98                 break;
99         case PixelFormat_8BitBGRA:
100                 first = userdata->tex_rgba[field] == 0;
101                 break;
102         case PixelFormat_8BitYCbCrPlanar:
103                 first = userdata->tex_y[field] == 0 || userdata->tex_cb[field] == 0 || userdata->tex_cr[field] == 0;
104                 break;
105         default:
106                 assert(false);
107         }
108
109         if (first ||
110             width != userdata->last_width[field] ||
111             height != userdata->last_height[field] ||
112             cbcr_width != userdata->last_cbcr_width[field] ||
113             cbcr_height != userdata->last_cbcr_height[field]) {
114                 // We changed resolution since last use of this texture, so we need to create
115                 // a new object. Note that this each card has its own PBOFrameAllocator,
116                 // we don't need to worry about these flip-flopping between resolutions.
117                 switch (userdata->pixel_format) {
118                 case PixelFormat_10BitYCbCr:
119                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
120                         check_error();
121                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
122                         check_error();
123                         break;
124                 case PixelFormat_8BitYCbCr: {
125                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
126                         check_error();
127                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
128                         check_error();
129                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
130                         check_error();
131                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
132                         check_error();
133                         break;
134                 }
135                 case PixelFormat_8BitYCbCrPlanar: {
136                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
137                         check_error();
138                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
139                         check_error();
140                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cb[field]);
141                         check_error();
142                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
143                         check_error();
144                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cr[field]);
145                         check_error();
146                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
147                         check_error();
148                         break;
149                 }
150                 case PixelFormat_8BitBGRA:
151                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
152                         check_error();
153                         if (global_flags.can_disable_srgb_decoder) {  // See the comments in tweaked_inputs.h.
154                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
155                         } else {
156                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
157                         }
158                         check_error();
159                         break;
160                 default:
161                         assert(false);
162                 }
163                 userdata->last_width[field] = width;
164                 userdata->last_height[field] = height;
165                 userdata->last_cbcr_width[field] = cbcr_width;
166                 userdata->last_cbcr_height[field] = cbcr_height;
167         }
168         if (global_flags.ten_bit_input &&
169             (first || v210_width != userdata->last_v210_width[field])) {
170                 // Same as above; we need to recreate the texture.
171                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
172                 check_error();
173                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
174                 check_error();
175                 userdata->last_v210_width[field] = v210_width;
176         }
177 }
178
179 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
180 {
181         if (interlaced_stride) {
182                 stride *= 2;
183         }
184         if (global_flags.flush_pbos) {
185                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
186                 check_error();
187         }
188
189         glBindTexture(GL_TEXTURE_2D, tex);
190         check_error();
191         if (interlaced_stride) {
192                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
193                 check_error();
194         } else {
195                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
196                 check_error();
197         }
198
199         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
200         check_error();
201         glBindTexture(GL_TEXTURE_2D, 0);
202         check_error();
203         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
204         check_error();
205 }
206
207 }  // namespace
208
209 void JitterHistory::register_metrics(const vector<pair<string, string>> &labels)
210 {
211         global_metrics.add("input_underestimated_jitter_frames", labels, &metric_input_underestimated_jitter_frames);
212         global_metrics.add("input_estimated_max_jitter_seconds", labels, &metric_input_estimated_max_jitter_seconds, Metrics::TYPE_GAUGE);
213 }
214
215 void JitterHistory::unregister_metrics(const vector<pair<string, string>> &labels)
216 {
217         global_metrics.remove("input_underestimated_jitter_frames", labels);
218         global_metrics.remove("input_estimated_max_jitter_seconds", labels);
219 }
220
221 void JitterHistory::frame_arrived(steady_clock::time_point now, int64_t frame_duration, size_t dropped_frames)
222 {
223         if (expected_timestamp > steady_clock::time_point::min()) {
224                 expected_timestamp += dropped_frames * nanoseconds(frame_duration * 1000000000 / TIMEBASE);
225                 double jitter_seconds = fabs(duration<double>(expected_timestamp - now).count());
226                 history.push_back(orders.insert(jitter_seconds));
227                 if (jitter_seconds > estimate_max_jitter()) {
228                         ++metric_input_underestimated_jitter_frames;
229                 }
230
231                 metric_input_estimated_max_jitter_seconds = estimate_max_jitter();
232
233                 if (history.size() > history_length) {
234                         orders.erase(history.front());
235                         history.pop_front();
236                 }
237                 assert(history.size() <= history_length);
238         }
239         expected_timestamp = now + nanoseconds(frame_duration * 1000000000 / TIMEBASE);
240 }
241
242 double JitterHistory::estimate_max_jitter() const
243 {
244         if (orders.empty()) {
245                 return 0.0;
246         }
247         size_t elem_idx = lrint((orders.size() - 1) * percentile);
248         if (percentile <= 0.5) {
249                 return *next(orders.begin(), elem_idx) * multiplier;
250         } else {
251                 return *prev(orders.end(), orders.size() - elem_idx) * multiplier;
252         }
253 }
254
255 void QueueLengthPolicy::register_metrics(const vector<pair<string, string>> &labels)
256 {
257         global_metrics.add("input_queue_safe_length_frames", labels, &metric_input_queue_safe_length_frames, Metrics::TYPE_GAUGE);
258 }
259
260 void QueueLengthPolicy::unregister_metrics(const vector<pair<string, string>> &labels)
261 {
262         global_metrics.remove("input_queue_safe_length_frames", labels);
263 }
264
265 void QueueLengthPolicy::update_policy(steady_clock::time_point now,
266                                       steady_clock::time_point expected_next_frame,
267                                       int64_t input_frame_duration,
268                                       int64_t master_frame_duration,
269                                       double max_input_card_jitter_seconds,
270                                       double max_master_card_jitter_seconds)
271 {
272         double input_frame_duration_seconds = input_frame_duration / double(TIMEBASE);
273         double master_frame_duration_seconds = master_frame_duration / double(TIMEBASE);
274
275         // Figure out when we can expect the next frame for this card, assuming
276         // worst-case jitter (ie., the frame is maximally late).
277         double seconds_until_next_frame = max(duration<double>(expected_next_frame - now).count() + max_input_card_jitter_seconds, 0.0);
278
279         // How many times are the master card expected to tick in that time?
280         // We assume the master clock has worst-case jitter but not any rate
281         // discrepancy, ie., it ticks as early as possible every time, but not
282         // cumulatively.
283         double frames_needed = (seconds_until_next_frame + max_master_card_jitter_seconds) / master_frame_duration_seconds;
284
285         // As a special case, if the master card ticks faster than the input card,
286         // we expect the queue to drain by itself even without dropping. But if
287         // the difference is small (e.g. 60 Hz master and 59.94 input), it would
288         // go slowly enough that the effect wouldn't really be appreciable.
289         // We account for this by looking at the situation five frames ahead,
290         // assuming everything else is the same.
291         double frames_allowed;
292         if (master_frame_duration < input_frame_duration) {
293                 frames_allowed = frames_needed + 5 * (input_frame_duration_seconds - master_frame_duration_seconds) / master_frame_duration_seconds;
294         } else {
295                 frames_allowed = frames_needed;
296         }
297
298         safe_queue_length = max<int>(floor(frames_allowed), 0);
299         metric_input_queue_safe_length_frames = safe_queue_length;
300 }
301
302 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
303         : httpd(),
304           num_cards(num_cards),
305           mixer_surface(create_surface(format)),
306           h264_encoder_surface(create_surface(format)),
307           decklink_output_surface(create_surface(format))
308 {
309         memcpy(ycbcr_interpretation, global_flags.ycbcr_interpretation, sizeof(ycbcr_interpretation));
310         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
311         check_error();
312
313         // This nearly always should be true.
314         global_flags.can_disable_srgb_decoder =
315                 epoxy_has_gl_extension("GL_EXT_texture_sRGB_decode") &&
316                 epoxy_has_gl_extension("GL_ARB_sampler_objects");
317
318         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
319         // will be halved when sampling them, and we need to compensate here.
320         movit_texel_subpixel_precision /= 2.0;
321
322         resource_pool.reset(new ResourcePool);
323         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
324                 output_channel[i].parent = this;
325                 output_channel[i].channel = i;
326         }
327
328         ImageFormat inout_format;
329         inout_format.color_space = COLORSPACE_sRGB;
330         inout_format.gamma_curve = GAMMA_sRGB;
331
332         // Matches the 4:2:0 format created by the main chain.
333         YCbCrFormat ycbcr_format;
334         ycbcr_format.chroma_subsampling_x = 2;
335         ycbcr_format.chroma_subsampling_y = 2;
336         if (global_flags.ycbcr_rec709_coefficients) {
337                 ycbcr_format.luma_coefficients = YCBCR_REC_709;
338         } else {
339                 ycbcr_format.luma_coefficients = YCBCR_REC_601;
340         }
341         ycbcr_format.full_range = false;
342         ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
343         ycbcr_format.cb_x_position = 0.0f;
344         ycbcr_format.cr_x_position = 0.0f;
345         ycbcr_format.cb_y_position = 0.5f;
346         ycbcr_format.cr_y_position = 0.5f;
347
348         // Display chain; shows the live output produced by the main chain (or rather, a copy of it).
349         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
350         check_error();
351         GLenum type = global_flags.x264_bit_depth > 8 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_BYTE;
352         display_input = new YCbCrInput(inout_format, ycbcr_format, global_flags.width, global_flags.height, YCBCR_INPUT_SPLIT_Y_AND_CBCR, type);
353         display_chain->add_input(display_input);
354         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
355         display_chain->set_dither_bits(0);  // Don't bother.
356         display_chain->finalize();
357
358         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));
359
360         // Must be instantiated after VideoEncoder has initialized global_flags.use_zerocopy.
361         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
362
363         // Must be instantiated after the theme, as the theme decides the number of FFmpeg inputs.
364         std::vector<FFmpegCapture *> video_inputs = theme->get_video_inputs();
365         audio_mixer.reset(new AudioMixer(num_cards, video_inputs.size()));
366
367         httpd.add_endpoint("/channels", bind(&Mixer::get_channels_json, this), HTTPD::ALLOW_ALL_ORIGINS);
368         for (int channel_idx = 2; channel_idx < theme->get_num_channels(); ++channel_idx) {
369                 char url[256];
370                 snprintf(url, sizeof(url), "/channels/%d/color", channel_idx);
371                 httpd.add_endpoint(url, bind(&Mixer::get_channel_color_http, this, unsigned(channel_idx)), HTTPD::ALLOW_ALL_ORIGINS);
372         }
373
374         // Start listening for clients only once VideoEncoder has written its header, if any.
375         httpd.start(global_flags.http_port);
376
377         // First try initializing the then PCI devices, then USB, then
378         // fill up with fake cards until we have the desired number of cards.
379         unsigned num_pci_devices = 0;
380         unsigned card_index = 0;
381
382         {
383                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
384                 if (decklink_iterator != nullptr) {
385                         for ( ; card_index < num_cards; ++card_index) {
386                                 IDeckLink *decklink;
387                                 if (decklink_iterator->Next(&decklink) != S_OK) {
388                                         break;
389                                 }
390
391                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
392                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
393                                 if (!output->set_device(decklink)) {
394                                         delete output;
395                                         output = nullptr;
396                                 }
397                                 configure_card(card_index, capture, CardType::LIVE_CARD, output);
398                                 ++num_pci_devices;
399                         }
400                         decklink_iterator->Release();
401                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
402                 } else {
403                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
404                 }
405         }
406
407         unsigned num_usb_devices = BMUSBCapture::num_cards();
408         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
409                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
410                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
411                 configure_card(card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
412         }
413         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
414
415         unsigned num_fake_cards = 0;
416         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
417                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
418                 configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
419         }
420
421         if (num_fake_cards > 0) {
422                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
423         }
424
425         // Initialize all video inputs the theme asked for. Note that these are
426         // all put _after_ the regular cards, which stop at <num_cards> - 1.
427         for (unsigned video_card_index = 0; video_card_index < video_inputs.size(); ++card_index, ++video_card_index) {
428                 if (card_index >= MAX_VIDEO_CARDS) {
429                         fprintf(stderr, "ERROR: Not enough card slots available for the videos the theme requested.\n");
430                         exit(1);
431                 }
432                 configure_card(card_index, video_inputs[video_card_index], CardType::FFMPEG_INPUT, /*output=*/nullptr);
433                 video_inputs[video_card_index]->set_card_index(card_index);
434         }
435         num_video_inputs = video_inputs.size();
436
437 #ifdef HAVE_CEF
438         // Same, for HTML inputs.
439         std::vector<CEFCapture *> html_inputs = theme->get_html_inputs();
440         for (unsigned html_card_index = 0; html_card_index < html_inputs.size(); ++card_index, ++html_card_index) {
441                 if (card_index >= MAX_VIDEO_CARDS) {
442                         fprintf(stderr, "ERROR: Not enough card slots available for the HTML inputs the theme requested.\n");
443                         exit(1);
444                 }
445                 configure_card(card_index, html_inputs[html_card_index], CardType::CEF_INPUT, /*output=*/nullptr);
446                 html_inputs[html_card_index]->set_card_index(card_index);
447         }
448         num_html_inputs = html_inputs.size();
449 #endif
450
451         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
452         BMUSBCapture::start_bm_thread();
453
454         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
455                 cards[card_index].queue_length_policy.reset(card_index);
456         }
457
458         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
459
460         if (global_flags.ten_bit_input) {
461                 if (!v210Converter::has_hardware_support()) {
462                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
463                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
464                         exit(1);
465                 }
466                 v210_converter.reset(new v210Converter());
467
468                 // These are all the widths listed in the Blackmagic SDK documentation
469                 // (section 2.7.3, “Display Modes”).
470                 v210_converter->precompile_shader(720);
471                 v210_converter->precompile_shader(1280);
472                 v210_converter->precompile_shader(1920);
473                 v210_converter->precompile_shader(2048);
474                 v210_converter->precompile_shader(3840);
475                 v210_converter->precompile_shader(4096);
476         }
477         if (global_flags.ten_bit_output) {
478                 if (!v210Converter::has_hardware_support()) {
479                         fprintf(stderr, "ERROR: --ten-bit-output requires support for OpenGL compute shaders\n");
480                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
481                         exit(1);
482                 }
483         }
484
485         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
486         display_timecode_in_stream = global_flags.display_timecode_in_stream;
487         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
488
489         if (global_flags.enable_alsa_output) {
490                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
491         }
492         if (global_flags.output_card != -1) {
493                 desired_output_card_index = global_flags.output_card;
494                 set_output_card_internal(global_flags.output_card);
495         }
496
497         output_jitter_history.register_metrics({{ "card", "output" }});
498 }
499
500 Mixer::~Mixer()
501 {
502         httpd.stop();
503         BMUSBCapture::stop_bm_thread();
504
505         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
506                 {
507                         unique_lock<mutex> lock(card_mutex);
508                         cards[card_index].should_quit = true;  // Unblock thread.
509                         cards[card_index].new_frames_changed.notify_all();
510                 }
511                 cards[card_index].capture->stop_dequeue_thread();
512                 if (cards[card_index].output) {
513                         cards[card_index].output->end_output();
514                         cards[card_index].output.reset();
515                 }
516         }
517
518         video_encoder.reset(nullptr);
519 }
520
521 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, CardType card_type, DeckLinkOutput *output)
522 {
523         printf("Configuring card %d...\n", card_index);
524
525         CaptureCard *card = &cards[card_index];
526         if (card->capture != nullptr) {
527                 card->capture->stop_dequeue_thread();
528         }
529         card->capture.reset(capture);
530         card->is_fake_capture = (card_type == CardType::FAKE_CAPTURE);
531         card->is_cef_capture = (card_type == CardType::CEF_INPUT);
532         card->may_have_dropped_last_frame = false;
533         card->type = card_type;
534         if (card->output.get() != output) {
535                 card->output.reset(output);
536         }
537
538         PixelFormat pixel_format;
539         if (card_type == CardType::FFMPEG_INPUT) {
540                 pixel_format = capture->get_current_pixel_format();
541         } else if (card_type == CardType::CEF_INPUT) {
542                 pixel_format = PixelFormat_8BitBGRA;
543         } else if (global_flags.ten_bit_input) {
544                 pixel_format = PixelFormat_10BitYCbCr;
545         } else {
546                 pixel_format = PixelFormat_8BitYCbCr;
547         }
548
549         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
550         if (card->frame_allocator == nullptr) {
551                 card->frame_allocator.reset(new PBOFrameAllocator(pixel_format, 8 << 20, global_flags.width, global_flags.height));  // 8 MB.
552         }
553         card->capture->set_video_frame_allocator(card->frame_allocator.get());
554         if (card->surface == nullptr) {
555                 card->surface = create_surface_with_same_format(mixer_surface);
556         }
557         while (!card->new_frames.empty()) card->new_frames.pop_front();
558         card->last_timecode = -1;
559         card->capture->set_pixel_format(pixel_format);
560         card->capture->configure_card();
561
562         // NOTE: start_bm_capture() happens in thread_func().
563
564         DeviceSpec device;
565         if (card_type == CardType::FFMPEG_INPUT) {
566                 device = DeviceSpec{InputSourceType::FFMPEG_VIDEO_INPUT, card_index - num_cards};
567         } else {
568                 device = DeviceSpec{InputSourceType::CAPTURE_CARD, card_index};
569         }
570         audio_mixer->reset_resampler(device);
571         audio_mixer->set_display_name(device, card->capture->get_description());
572         audio_mixer->trigger_state_changed_callback();
573
574         // Unregister old metrics, if any.
575         if (!card->labels.empty()) {
576                 const vector<pair<string, string>> &labels = card->labels;
577                 card->jitter_history.unregister_metrics(labels);
578                 card->queue_length_policy.unregister_metrics(labels);
579                 global_metrics.remove("input_received_frames", labels);
580                 global_metrics.remove("input_dropped_frames_jitter", labels);
581                 global_metrics.remove("input_dropped_frames_error", labels);
582                 global_metrics.remove("input_dropped_frames_resets", labels);
583                 global_metrics.remove("input_queue_length_frames", labels);
584                 global_metrics.remove("input_queue_duped_frames", labels);
585
586                 global_metrics.remove("input_has_signal_bool", labels);
587                 global_metrics.remove("input_is_connected_bool", labels);
588                 global_metrics.remove("input_interlaced_bool", labels);
589                 global_metrics.remove("input_width_pixels", labels);
590                 global_metrics.remove("input_height_pixels", labels);
591                 global_metrics.remove("input_frame_rate_nom", labels);
592                 global_metrics.remove("input_frame_rate_den", labels);
593                 global_metrics.remove("input_sample_rate_hz", labels);
594         }
595
596         // Register metrics.
597         vector<pair<string, string>> labels;
598         char card_name[64];
599         snprintf(card_name, sizeof(card_name), "%d", card_index);
600         labels.emplace_back("card", card_name);
601
602         switch (card_type) {
603         case CardType::LIVE_CARD:
604                 labels.emplace_back("cardtype", "live");
605                 break;
606         case CardType::FAKE_CAPTURE:
607                 labels.emplace_back("cardtype", "fake");
608                 break;
609         case CardType::FFMPEG_INPUT:
610                 labels.emplace_back("cardtype", "ffmpeg");
611                 break;
612         case CardType::CEF_INPUT:
613                 labels.emplace_back("cardtype", "cef");
614                 break;
615         default:
616                 assert(false);
617         }
618         card->jitter_history.register_metrics(labels);
619         card->queue_length_policy.register_metrics(labels);
620         global_metrics.add("input_received_frames", labels, &card->metric_input_received_frames);
621         global_metrics.add("input_dropped_frames_jitter", labels, &card->metric_input_dropped_frames_jitter);
622         global_metrics.add("input_dropped_frames_error", labels, &card->metric_input_dropped_frames_error);
623         global_metrics.add("input_dropped_frames_resets", labels, &card->metric_input_resets);
624         global_metrics.add("input_queue_length_frames", labels, &card->metric_input_queue_length_frames, Metrics::TYPE_GAUGE);
625         global_metrics.add("input_queue_duped_frames", labels, &card->metric_input_duped_frames);
626
627         global_metrics.add("input_has_signal_bool", labels, &card->metric_input_has_signal_bool, Metrics::TYPE_GAUGE);
628         global_metrics.add("input_is_connected_bool", labels, &card->metric_input_is_connected_bool, Metrics::TYPE_GAUGE);
629         global_metrics.add("input_interlaced_bool", labels, &card->metric_input_interlaced_bool, Metrics::TYPE_GAUGE);
630         global_metrics.add("input_width_pixels", labels, &card->metric_input_width_pixels, Metrics::TYPE_GAUGE);
631         global_metrics.add("input_height_pixels", labels, &card->metric_input_height_pixels, Metrics::TYPE_GAUGE);
632         global_metrics.add("input_frame_rate_nom", labels, &card->metric_input_frame_rate_nom, Metrics::TYPE_GAUGE);
633         global_metrics.add("input_frame_rate_den", labels, &card->metric_input_frame_rate_den, Metrics::TYPE_GAUGE);
634         global_metrics.add("input_sample_rate_hz", labels, &card->metric_input_sample_rate_hz, Metrics::TYPE_GAUGE);
635         card->labels = labels;
636 }
637
638 void Mixer::set_output_card_internal(int card_index)
639 {
640         // We don't really need to take card_mutex, since we're in the mixer
641         // thread and don't mess with any queues (which is the only thing that happens
642         // from other threads), but it's probably the safest in the long run.
643         unique_lock<mutex> lock(card_mutex);
644         if (output_card_index != -1) {
645                 // Switch the old card from output to input.
646                 CaptureCard *old_card = &cards[output_card_index];
647                 old_card->output->end_output();
648
649                 // Stop the fake card that we put into place.
650                 // This needs to _not_ happen under the mutex, to avoid deadlock
651                 // (delivering the last frame needs to take the mutex).
652                 CaptureInterface *fake_capture = old_card->capture.get();
653                 lock.unlock();
654                 fake_capture->stop_dequeue_thread();
655                 lock.lock();
656                 old_card->capture = move(old_card->parked_capture);  // TODO: reset the metrics
657                 old_card->is_fake_capture = false;
658                 old_card->capture->start_bm_capture();
659         }
660         if (card_index != -1) {
661                 CaptureCard *card = &cards[card_index];
662                 CaptureInterface *capture = card->capture.get();
663                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
664                 // several seconds to complete (blocking on DisableVideoInput);
665                 // see if we can maybe do it asynchronously.
666                 lock.unlock();
667                 capture->stop_dequeue_thread();
668                 lock.lock();
669                 card->parked_capture = move(card->capture);
670                 CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
671                 configure_card(card_index, fake_capture, CardType::FAKE_CAPTURE, card->output.release());
672                 card->queue_length_policy.reset(card_index);
673                 card->capture->start_bm_capture();
674                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
675                 card->output->start_output(desired_output_video_mode, pts_int);
676         }
677         output_card_index = card_index;
678         output_jitter_history.clear();
679 }
680
681 namespace {
682
683 int unwrap_timecode(uint16_t current_wrapped, int last)
684 {
685         uint16_t last_wrapped = last & 0xffff;
686         if (current_wrapped > last_wrapped) {
687                 return (last & ~0xffff) | current_wrapped;
688         } else {
689                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
690         }
691 }
692
693 }  // namespace
694
695 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
696                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
697                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
698 {
699         DeviceSpec device;
700         if (card_index >= num_cards) {
701                 device = DeviceSpec{InputSourceType::FFMPEG_VIDEO_INPUT, card_index - num_cards};
702         } else {
703                 device = DeviceSpec{InputSourceType::CAPTURE_CARD, card_index};
704         }
705         CaptureCard *card = &cards[card_index];
706
707         ++card->metric_input_received_frames;
708         card->metric_input_has_signal_bool = video_format.has_signal;
709         card->metric_input_is_connected_bool = video_format.is_connected;
710         card->metric_input_interlaced_bool = video_format.interlaced;
711         card->metric_input_width_pixels = video_format.width;
712         card->metric_input_height_pixels = video_format.height;
713         card->metric_input_frame_rate_nom = video_format.frame_rate_nom;
714         card->metric_input_frame_rate_den = video_format.frame_rate_den;
715         card->metric_input_sample_rate_hz = audio_format.sample_rate;
716
717         if (is_mode_scanning[card_index]) {
718                 if (video_format.has_signal) {
719                         // Found a stable signal, so stop scanning.
720                         is_mode_scanning[card_index] = false;
721                 } else {
722                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
723                         steady_clock::time_point now = steady_clock::now();
724                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
725                         if (sec_since_last_switch > switch_time_s) {
726                                 // It isn't this mode; try the next one.
727                                 mode_scanlist_index[card_index]++;
728                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
729                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
730                                 last_mode_scan_change[card_index] = now;
731                         }
732                 }
733         }
734
735         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
736         assert(frame_length > 0);
737
738         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;
739         if (num_samples > OUTPUT_FREQUENCY / 10 && card->type != CardType::FFMPEG_INPUT) {
740                 printf("%s: Dropping frame with implausible audio length (len=%d, offset=%d) [timecode=0x%04x video_len=%d video_offset=%d video_format=%x)\n",
741                         spec_to_string(device).c_str(), int(audio_frame.len), int(audio_offset),
742                         timecode, int(video_frame.len), int(video_offset), video_format.id);
743                 if (video_frame.owner) {
744                         video_frame.owner->release_frame(video_frame);
745                 }
746                 if (audio_frame.owner) {
747                         audio_frame.owner->release_frame(audio_frame);
748                 }
749                 return;
750         }
751
752         int dropped_frames = 0;
753         if (card->last_timecode != -1) {
754                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
755         }
756
757         // Number of samples per frame if we need to insert silence.
758         // (Could be nonintegral, but resampling will save us then.)
759         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
760
761         if (dropped_frames > MAX_FPS * 2) {
762                 fprintf(stderr, "%s lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
763                         spec_to_string(device).c_str(), card->last_timecode, timecode);
764                 audio_mixer->reset_resampler(device);
765                 dropped_frames = 0;
766                 ++card->metric_input_resets;
767         } else if (dropped_frames > 0) {
768                 // Insert silence as needed.
769                 fprintf(stderr, "%s dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
770                         spec_to_string(device).c_str(), dropped_frames, timecode);
771                 card->metric_input_dropped_frames_error += dropped_frames;
772
773                 bool success;
774                 do {
775                         success = audio_mixer->add_silence(device, silence_samples, dropped_frames, frame_length);
776                 } while (!success);
777         }
778
779         if (num_samples > 0) {
780                 audio_mixer->add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
781         }
782
783         // Done with the audio, so release it.
784         if (audio_frame.owner) {
785                 audio_frame.owner->release_frame(audio_frame);
786         }
787
788         card->last_timecode = timecode;
789
790         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
791
792         size_t cbcr_width, cbcr_height, cbcr_offset, y_offset;
793         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
794         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
795                 // The calculation above is wrong for planar Y'CbCr, so just override it.
796                 assert(card->type == CardType::FFMPEG_INPUT);
797                 assert(video_offset == 0);
798                 expected_length = video_frame.len;
799
800                 userdata->ycbcr_format = (static_cast<FFmpegCapture *>(card->capture.get()))->get_current_frame_ycbcr_format();
801                 cbcr_width = video_format.width / userdata->ycbcr_format.chroma_subsampling_x;
802                 cbcr_height = video_format.height / userdata->ycbcr_format.chroma_subsampling_y;
803                 cbcr_offset = video_format.width * video_format.height;
804                 y_offset = 0;
805         } else {
806                 // All the other Y'CbCr formats are 4:2:2.
807                 cbcr_width = video_format.width / 2;
808                 cbcr_height = video_format.height;
809                 cbcr_offset = video_offset / 2;
810                 y_offset = video_frame.size / 2 + video_offset / 2;
811         }
812         if (video_frame.len - video_offset == 0 ||
813             video_frame.len - video_offset != expected_length) {
814                 if (video_frame.len != 0) {
815                         printf("%s: Dropping video frame with wrong length (%ld; expected %ld)\n",
816                                 spec_to_string(device).c_str(), video_frame.len - video_offset, expected_length);
817                 }
818                 if (video_frame.owner) {
819                         video_frame.owner->release_frame(video_frame);
820                 }
821
822                 // Still send on the information that we _had_ a frame, even though it's corrupted,
823                 // so that pts can go up accordingly.
824                 {
825                         unique_lock<mutex> lock(card_mutex);
826                         CaptureCard::NewFrame new_frame;
827                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
828                         new_frame.length = frame_length;
829                         new_frame.interlaced = false;
830                         new_frame.dropped_frames = dropped_frames;
831                         new_frame.received_timestamp = video_frame.received_timestamp;
832                         card->new_frames.push_back(move(new_frame));
833                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
834                 }
835                 card->new_frames_changed.notify_all();
836                 return;
837         }
838
839         unsigned num_fields = video_format.interlaced ? 2 : 1;
840         steady_clock::time_point frame_upload_start;
841         bool interlaced_stride = false;
842         if (video_format.interlaced) {
843                 // Send the two fields along as separate frames; the other side will need to add
844                 // a deinterlacer to actually get this right.
845                 assert(video_format.height % 2 == 0);
846                 video_format.height /= 2;
847                 cbcr_height /= 2;
848                 assert(frame_length % 2 == 0);
849                 frame_length /= 2;
850                 num_fields = 2;
851                 if (video_format.second_field_start == 1) {
852                         interlaced_stride = true;
853                 }
854                 frame_upload_start = steady_clock::now();
855         }
856         userdata->last_interlaced = video_format.interlaced;
857         userdata->last_has_signal = video_format.has_signal;
858         userdata->last_is_connected = video_format.is_connected;
859         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
860         userdata->last_frame_rate_den = video_format.frame_rate_den;
861         RefCountedFrame frame(video_frame);
862
863         // Upload the textures.
864         for (unsigned field = 0; field < num_fields; ++field) {
865                 // Put the actual texture upload in a lambda that is executed in the main thread.
866                 // It is entirely possible to do this in the same thread (and it might even be
867                 // faster, depending on the GPU and driver), but it appears to be trickling
868                 // driver bugs very easily.
869                 //
870                 // Note that this means we must hold on to the actual frame data in <userdata>
871                 // until the upload command is run, but we hold on to <frame> much longer than that
872                 // (in fact, all the way until we no longer use the texture in rendering).
873                 auto upload_func = [this, field, video_format, y_offset, video_offset, cbcr_offset, cbcr_width, cbcr_height, interlaced_stride, userdata]() {
874                         unsigned field_start_line;
875                         if (field == 1) {
876                                 field_start_line = video_format.second_field_start;
877                         } else {
878                                 field_start_line = video_format.extra_lines_top;
879                         }
880
881                         // For anything not FRAME_FORMAT_YCBCR_10BIT, v210_width will be nonsensical but not used.
882                         size_t v210_width = video_format.stride / sizeof(uint32_t);
883                         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, cbcr_width, cbcr_height, v210_width);
884
885                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
886                         check_error();
887
888                         switch (userdata->pixel_format) {
889                         case PixelFormat_10BitYCbCr: {
890                                 size_t field_start = video_offset + video_format.stride * field_start_line;
891                                 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);
892                                 v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
893                                 break;
894                         }
895                         case PixelFormat_8BitYCbCr: {
896                                 size_t field_y_start = y_offset + video_format.width * field_start_line;
897                                 size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
898
899                                 // Make up our own strides, since we are interleaving.
900                                 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);
901                                 upload_texture(userdata->tex_cbcr[field], cbcr_width, cbcr_height, cbcr_width * sizeof(uint16_t), interlaced_stride, GL_RG, GL_UNSIGNED_BYTE, field_cbcr_start);
902                                 break;
903                         }
904                         case PixelFormat_8BitYCbCrPlanar: {
905                                 assert(field_start_line == 0);  // We don't really support interlaced here.
906                                 size_t field_y_start = y_offset;
907                                 size_t field_cb_start = cbcr_offset;
908                                 size_t field_cr_start = cbcr_offset + cbcr_width * cbcr_height;
909
910                                 // Make up our own strides, since we are interleaving.
911                                 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);
912                                 upload_texture(userdata->tex_cb[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cb_start);
913                                 upload_texture(userdata->tex_cr[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cr_start);
914                                 break;
915                         }
916                         case PixelFormat_8BitBGRA: {
917                                 size_t field_start = video_offset + video_format.stride * field_start_line;
918                                 upload_texture(userdata->tex_rgba[field], video_format.width, video_format.height, video_format.stride, interlaced_stride, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, field_start);
919                                 // These could be asked to deliver mipmaps at any time.
920                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
921                                 check_error();
922                                 glGenerateMipmap(GL_TEXTURE_2D);
923                                 check_error();
924                                 glBindTexture(GL_TEXTURE_2D, 0);
925                                 check_error();
926                                 break;
927                         }
928                         default:
929                                 assert(false);
930                         }
931
932                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
933                         check_error();
934                 };
935
936                 if (field == 1) {
937                         // Don't upload the second field as fast as we can; wait until
938                         // the field time has approximately passed. (Otherwise, we could
939                         // get timing jitter against the other sources, and possibly also
940                         // against the video display, although the latter is not as critical.)
941                         // This requires our system clock to be reasonably close to the
942                         // video clock, but that's not an unreasonable assumption.
943                         steady_clock::time_point second_field_start = frame_upload_start +
944                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
945                         this_thread::sleep_until(second_field_start);
946                 }
947
948                 {
949                         unique_lock<mutex> lock(card_mutex);
950                         CaptureCard::NewFrame new_frame;
951                         new_frame.frame = frame;
952                         new_frame.length = frame_length;
953                         new_frame.field = field;
954                         new_frame.interlaced = video_format.interlaced;
955                         new_frame.upload_func = upload_func;
956                         new_frame.dropped_frames = dropped_frames;
957                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
958                         card->new_frames.push_back(move(new_frame));
959                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
960                         card->may_have_dropped_last_frame = false;
961                 }
962                 card->new_frames_changed.notify_all();
963         }
964 }
965
966 void Mixer::bm_hotplug_add(libusb_device *dev)
967 {
968         lock_guard<mutex> lock(hotplug_mutex);
969         hotplugged_cards.push_back(dev);
970 }
971
972 void Mixer::bm_hotplug_remove(unsigned card_index)
973 {
974         cards[card_index].new_frames_changed.notify_all();
975 }
976
977 void Mixer::thread_func()
978 {
979         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
980
981         eglBindAPI(EGL_OPENGL_API);
982         QOpenGLContext *context = create_context(mixer_surface);
983         if (!make_current(context, mixer_surface)) {
984                 printf("oops\n");
985                 exit(1);
986         }
987
988         // Start the actual capture. (We don't want to do it before we're actually ready
989         // to process output frames.)
990         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
991                 if (int(card_index) != output_card_index) {
992                         cards[card_index].capture->start_bm_capture();
993                 }
994         }
995
996         BasicStats basic_stats(/*verbose=*/true, /*use_opengl=*/true);
997         int stats_dropped_frames = 0;
998
999         while (!should_quit) {
1000                 if (desired_output_card_index != output_card_index) {
1001                         set_output_card_internal(desired_output_card_index);
1002                 }
1003                 if (output_card_index != -1 &&
1004                     desired_output_video_mode != output_video_mode) {
1005                         DeckLinkOutput *output = cards[output_card_index].output.get();
1006                         output->end_output();
1007                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
1008                         output->start_output(desired_output_video_mode, pts_int);
1009                 }
1010
1011                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
1012                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
1013
1014                 bool master_card_is_output;
1015                 unsigned master_card_index;
1016                 if (output_card_index != -1) {
1017                         master_card_is_output = true;
1018                         master_card_index = output_card_index;
1019                 } else {
1020                         master_card_is_output = false;
1021                         master_card_index = theme->map_signal(master_clock_channel);
1022                         assert(master_card_index < num_cards + num_video_inputs);
1023                 }
1024
1025                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
1026                 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);
1027                 stats_dropped_frames += output_frame_info.dropped_frames;
1028
1029                 handle_hotplugged_cards();
1030
1031                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1032                         if (card_index == master_card_index || !has_new_frame[card_index]) {
1033                                 continue;
1034                         }
1035                         if (new_frames[card_index].frame->len == 0) {
1036                                 ++new_frames[card_index].dropped_frames;
1037                         }
1038                         if (new_frames[card_index].dropped_frames > 0) {
1039                                 printf("Card %u dropped %d frames before this\n",
1040                                         card_index, int(new_frames[card_index].dropped_frames));
1041                         }
1042                 }
1043
1044                 // If the first card is reporting a corrupted or otherwise dropped frame,
1045                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
1046                 if (!master_card_is_output && new_frames[master_card_index].frame->len == 0) {
1047                         ++stats_dropped_frames;
1048                         pts_int += new_frames[master_card_index].length;
1049                         continue;
1050                 }
1051
1052                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1053                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
1054                                 continue;
1055
1056                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
1057                         assert(new_frame->frame != nullptr);
1058                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
1059                         check_error();
1060
1061                         // The new texture might need uploading before use.
1062                         if (new_frame->upload_func) {
1063                                 new_frame->upload_func();
1064                                 new_frame->upload_func = nullptr;
1065                         }
1066                 }
1067
1068                 int64_t frame_duration = output_frame_info.frame_duration;
1069                 render_one_frame(frame_duration);
1070                 {
1071                         lock_guard<mutex> lock(frame_num_mutex);
1072                         ++frame_num;
1073                 }
1074                 frame_num_updated.notify_all();
1075                 pts_int += frame_duration;
1076
1077                 basic_stats.update(frame_num, stats_dropped_frames);
1078                 // if (frame_num % 100 == 0) chain->print_phase_timing();
1079
1080                 if (should_cut.exchange(false)) {  // Test and clear.
1081                         video_encoder->do_cut(frame_num);
1082                 }
1083
1084 #if 0
1085                 // Reset every 100 frames, so that local variations in frame times
1086                 // (especially for the first few frames, when the shaders are
1087                 // compiled etc.) don't make it hard to measure for the entire
1088                 // remaining duration of the program.
1089                 if (frame == 10000) {
1090                         frame = 0;
1091                         start = now;
1092                 }
1093 #endif
1094                 check_error();
1095         }
1096
1097         resource_pool->clean_context();
1098 }
1099
1100 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
1101 {
1102         if (output_card_index != -1) {
1103                 // The output card (ie., cards[output_card_index].output) is the master clock,
1104                 // so no input card (ie., cards[card_index].capture) is.
1105                 return false;
1106         }
1107         return (card_index == master_card_index);
1108 }
1109
1110 void Mixer::trim_queue(CaptureCard *card, size_t safe_queue_length)
1111 {
1112         // Count the number of frames in the queue, including any frames
1113         // we dropped. It's hard to know exactly how we should deal with
1114         // dropped (corrupted) input frames; they don't help our goal of
1115         // avoiding starvation, but they still add to the problem of latency.
1116         // Since dropped frames is going to mean a bump in the signal anyway,
1117         // we err on the side of having more stable latency instead.
1118         unsigned queue_length = 0;
1119         for (const CaptureCard::NewFrame &frame : card->new_frames) {
1120                 queue_length += frame.dropped_frames + 1;
1121         }
1122
1123         // If needed, drop frames until the queue is below the safe limit.
1124         // We prefer to drop from the head, because all else being equal,
1125         // we'd like more recent frames (less latency).
1126         unsigned dropped_frames = 0;
1127         while (queue_length > safe_queue_length) {
1128                 assert(!card->new_frames.empty());
1129                 assert(queue_length > card->new_frames.front().dropped_frames);
1130                 queue_length -= card->new_frames.front().dropped_frames;
1131
1132                 if (queue_length <= safe_queue_length) {
1133                         // No need to drop anything.
1134                         break;
1135                 }
1136
1137                 card->new_frames.pop_front();
1138                 card->new_frames_changed.notify_all();
1139                 --queue_length;
1140                 ++dropped_frames;
1141
1142                 if (queue_length == 0 && card->is_cef_capture) {
1143                         card->may_have_dropped_last_frame = true;
1144                 }
1145         }
1146
1147         card->metric_input_dropped_frames_jitter += dropped_frames;
1148         card->metric_input_queue_length_frames = queue_length;
1149
1150 #if 0
1151         if (dropped_frames > 0) {
1152                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
1153                         card_index, dropped_frames);
1154         }
1155 #endif
1156 }
1157
1158 pair<string, string> Mixer::get_channels_json()
1159 {
1160         Channels ret;
1161         for (int channel_idx = 2; channel_idx < theme->get_num_channels(); ++channel_idx) {
1162                 Channel *channel = ret.add_channel();
1163                 channel->set_index(channel_idx);
1164                 channel->set_name(theme->get_channel_name(channel_idx));
1165                 channel->set_color(theme->get_channel_color(channel_idx));
1166         }
1167         string contents;
1168         google::protobuf::util::MessageToJsonString(ret, &contents);  // Ignore any errors.
1169         return make_pair(contents, "text/json");
1170 }
1171
1172 pair<string, string> Mixer::get_channel_color_http(unsigned channel_idx)
1173 {
1174         return make_pair(theme->get_channel_color(channel_idx), "text/plain");
1175 }
1176
1177 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])
1178 {
1179         OutputFrameInfo output_frame_info;
1180 start:
1181         unique_lock<mutex> lock(card_mutex, defer_lock);
1182         if (master_card_is_output) {
1183                 // Clocked to the output, so wait for it to be ready for the next frame.
1184                 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);
1185                 lock.lock();
1186         } else {
1187                 // Wait for the master card to have a new frame.
1188                 // TODO: Add a timeout.
1189                 output_frame_info.is_preroll = false;
1190                 lock.lock();
1191                 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(); });
1192         }
1193
1194         if (master_card_is_output) {
1195                 handle_hotplugged_cards();
1196         } else if (cards[master_card_index].new_frames.empty()) {
1197                 // We were woken up, but not due to a new frame. Deal with it
1198                 // and then restart.
1199                 assert(cards[master_card_index].capture->get_disconnected());
1200                 handle_hotplugged_cards();
1201                 lock.unlock();
1202                 goto start;
1203         }
1204
1205         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1206                 CaptureCard *card = &cards[card_index];
1207                 if (card->new_frames.empty()) {  // Starvation.
1208                         ++card->metric_input_duped_frames;
1209 #ifdef HAVE_CEF
1210                         if (card->is_cef_capture && card->may_have_dropped_last_frame) {
1211                                 // Unlike other sources, CEF is not guaranteed to send us a steady
1212                                 // stream of frames, so we'll have to ask it to repaint the frame
1213                                 // we dropped. (may_have_dropped_last_frame is set whenever we
1214                                 // trim the queue completely away, and cleared when we actually
1215                                 // get a new frame.)
1216                                 ((CEFCapture *)card->capture.get())->request_new_frame();
1217                         }
1218 #endif
1219                 } else {
1220                         new_frames[card_index] = move(card->new_frames.front());
1221                         has_new_frame[card_index] = true;
1222                         card->new_frames.pop_front();
1223                         card->new_frames_changed.notify_all();
1224                 }
1225         }
1226
1227         if (!master_card_is_output) {
1228                 output_frame_info.frame_timestamp = new_frames[master_card_index].received_timestamp;
1229                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
1230                 output_frame_info.frame_duration = new_frames[master_card_index].length;
1231         }
1232
1233         if (!output_frame_info.is_preroll) {
1234                 output_jitter_history.frame_arrived(output_frame_info.frame_timestamp, output_frame_info.frame_duration, output_frame_info.dropped_frames);
1235         }
1236
1237         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs + num_html_inputs; ++card_index) {
1238                 CaptureCard *card = &cards[card_index];
1239                 if (has_new_frame[card_index] &&
1240                     !input_card_is_master_clock(card_index, master_card_index) &&
1241                     !output_frame_info.is_preroll) {
1242                         card->queue_length_policy.update_policy(
1243                                 output_frame_info.frame_timestamp,
1244                                 card->jitter_history.get_expected_next_frame(),
1245                                 new_frames[master_card_index].length,
1246                                 output_frame_info.frame_duration,
1247                                 card->jitter_history.estimate_max_jitter(),
1248                                 output_jitter_history.estimate_max_jitter());
1249                         trim_queue(card, min<int>(global_flags.max_input_queue_frames,
1250                                                   card->queue_length_policy.get_safe_queue_length()));
1251                 }
1252         }
1253
1254         // This might get off by a fractional sample when changing master card
1255         // between ones with different frame rates, but that's fine.
1256         int num_samples_times_timebase = OUTPUT_FREQUENCY * output_frame_info.frame_duration + fractional_samples;
1257         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
1258         fractional_samples = num_samples_times_timebase % TIMEBASE;
1259         assert(output_frame_info.num_samples >= 0);
1260
1261         return output_frame_info;
1262 }
1263
1264 void Mixer::handle_hotplugged_cards()
1265 {
1266         // Check for cards that have been disconnected since last frame.
1267         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1268                 CaptureCard *card = &cards[card_index];
1269                 if (card->capture->get_disconnected()) {
1270                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
1271                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1272                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
1273                         card->queue_length_policy.reset(card_index);
1274                         card->capture->start_bm_capture();
1275                 }
1276         }
1277
1278         // Check for cards that have been connected since last frame.
1279         vector<libusb_device *> hotplugged_cards_copy;
1280         {
1281                 lock_guard<mutex> lock(hotplug_mutex);
1282                 swap(hotplugged_cards, hotplugged_cards_copy);
1283         }
1284         for (libusb_device *new_dev : hotplugged_cards_copy) {
1285                 // Look for a fake capture card where we can stick this in.
1286                 int free_card_index = -1;
1287                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1288                         if (cards[card_index].is_fake_capture) {
1289                                 free_card_index = card_index;
1290                                 break;
1291                         }
1292                 }
1293
1294                 if (free_card_index == -1) {
1295                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
1296                         libusb_unref_device(new_dev);
1297                 } else {
1298                         // BMUSBCapture takes ownership.
1299                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
1300                         CaptureCard *card = &cards[free_card_index];
1301                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
1302                         configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
1303                         card->queue_length_policy.reset(free_card_index);
1304                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1305                         capture->start_bm_capture();
1306                 }
1307         }
1308 }
1309
1310
1311 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)
1312 {
1313         // Resample the audio as needed, including from previously dropped frames.
1314         assert(num_cards > 0);
1315         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
1316                 const bool dropped_frame = (frame_num != dropped_frames);
1317                 {
1318                         // Signal to the audio thread to process this frame.
1319                         // Note that if the frame is a dropped frame, we signal that
1320                         // we don't want to use this frame as base for adjusting
1321                         // the resampler rate. The reason for this is that the timing
1322                         // of these frames is often way too late; they typically don't
1323                         // “arrive” before we synthesize them. Thus, we could end up
1324                         // in a situation where we have inserted e.g. five audio frames
1325                         // into the queue before we then start pulling five of them
1326                         // back out. This makes ResamplingQueue overestimate the delay,
1327                         // causing undue resampler changes. (We _do_ use the last,
1328                         // non-dropped frame; perhaps we should just discard that as well,
1329                         // since dropped frames are expected to be rare, and it might be
1330                         // better to just wait until we have a slightly more normal situation).
1331                         unique_lock<mutex> lock(audio_mutex);
1332                         bool adjust_rate = !dropped_frame && !is_preroll;
1333                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
1334                         audio_task_queue_changed.notify_one();
1335                 }
1336                 if (dropped_frame) {
1337                         // For dropped frames, increase the pts. Note that if the format changed
1338                         // in the meantime, we have no way of detecting that; we just have to
1339                         // assume the frame length is always the same.
1340                         pts_int += length_per_frame;
1341                 }
1342         }
1343 }
1344
1345 void Mixer::render_one_frame(int64_t duration)
1346 {
1347         // Determine the time code for this frame before we start rendering.
1348         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1349         if (display_timecode_on_stdout) {
1350                 printf("Timecode: '%s'\n", timecode_text.c_str());
1351         }
1352
1353         // Update Y'CbCr settings for all cards.
1354         {
1355                 unique_lock<mutex> lock(card_mutex);
1356                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1357                         YCbCrInterpretation *interpretation = &ycbcr_interpretation[card_index];
1358                         input_state.ycbcr_coefficients_auto[card_index] = interpretation->ycbcr_coefficients_auto;
1359                         input_state.ycbcr_coefficients[card_index] = interpretation->ycbcr_coefficients;
1360                         input_state.full_range[card_index] = interpretation->full_range;
1361                 }
1362         }
1363
1364         // Get the main chain from the theme, and set its state immediately.
1365         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1366         EffectChain *chain = theme_main_chain.chain;
1367         theme_main_chain.setup_chain();
1368         //theme_main_chain.chain->enable_phase_timing(true);
1369
1370         // If HDMI/SDI output is active and the user has requested auto mode,
1371         // its mode overrides the existing Y'CbCr setting for the chain.
1372         YCbCrLumaCoefficients ycbcr_output_coefficients;
1373         if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
1374                 ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
1375         } else {
1376                 ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
1377         }
1378
1379         // TODO: Reduce the duplication against theme.cpp.
1380         YCbCrFormat output_ycbcr_format;
1381         output_ycbcr_format.chroma_subsampling_x = 1;
1382         output_ycbcr_format.chroma_subsampling_y = 1;
1383         output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
1384         output_ycbcr_format.full_range = false;
1385         output_ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
1386         chain->change_ycbcr_output_format(output_ycbcr_format);
1387
1388         // Render main chain. If we're using zerocopy Quick Sync encoding
1389         // (the default case), we take an extra copy of the created outputs,
1390         // so that we can display it back to the screen later (it's less memory
1391         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1392         // Ideally, we'd like to avoid taking copies and just use the main textures
1393         // for display as well, but they're just views into VA-API memory and must be
1394         // unmapped during encoding, so we can't use them for display, unfortunately.
1395         GLuint y_tex, cbcr_full_tex, cbcr_tex;
1396         GLuint y_copy_tex, cbcr_copy_tex = 0;
1397         GLuint y_display_tex, cbcr_display_tex;
1398         GLenum y_type = (global_flags.x264_bit_depth > 8) ? GL_R16 : GL_R8;
1399         GLenum cbcr_type = (global_flags.x264_bit_depth > 8) ? GL_RG16 : GL_RG8;
1400         const bool is_zerocopy = video_encoder->is_zerocopy();
1401         if (is_zerocopy) {
1402                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1403                 y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1404                 cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1405
1406                 y_display_tex = y_copy_tex;
1407                 cbcr_display_tex = cbcr_copy_tex;
1408
1409                 // y_tex and cbcr_tex will be given by VideoEncoder.
1410         } else {
1411                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1412                 y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1413                 cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1414
1415                 y_display_tex = y_tex;
1416                 cbcr_display_tex = cbcr_tex;
1417         }
1418
1419         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1420         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1421         assert(got_frame);
1422
1423         GLuint fbo;
1424         if (is_zerocopy) {
1425                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1426         } else {
1427                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
1428         }
1429         check_error();
1430         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1431
1432         if (display_timecode_in_stream) {
1433                 // Render the timecode on top.
1434                 timecode_renderer->render_timecode(fbo, timecode_text);
1435         }
1436
1437         resource_pool->release_fbo(fbo);
1438
1439         if (is_zerocopy) {
1440                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1441         } else {
1442                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1443         }
1444         if (output_card_index != -1) {
1445                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
1446         }
1447         resource_pool->release_2d_texture(cbcr_full_tex);
1448
1449         // Set the right state for the Y' and CbCr textures we use for display.
1450         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1451         glBindTexture(GL_TEXTURE_2D, y_display_tex);
1452         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1453         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1454         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1455
1456         glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
1457         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1458         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1459         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1460
1461         RefCountedGLsync fence = video_encoder->end_frame();
1462
1463         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1464         // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
1465         DisplayFrame live_frame;
1466         live_frame.chain = display_chain.get();
1467         live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
1468                 display_input->set_texture_num(0, y_display_tex);
1469                 display_input->set_texture_num(1, cbcr_display_tex);
1470         };
1471         live_frame.ready_fence = fence;
1472         live_frame.input_frames = {};
1473         live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
1474         output_channel[OUTPUT_LIVE].output_frame(move(live_frame));
1475
1476         // Set up preview and any additional channels.
1477         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1478                 DisplayFrame display_frame;
1479                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1480                 display_frame.chain = move(chain.chain);
1481                 display_frame.setup_chain = move(chain.setup_chain);
1482                 display_frame.ready_fence = fence;
1483                 display_frame.input_frames = move(chain.input_frames);
1484                 display_frame.temp_textures = {};
1485                 output_channel[i].output_frame(move(display_frame));
1486         }
1487 }
1488
1489 void Mixer::audio_thread_func()
1490 {
1491         pthread_setname_np(pthread_self(), "Mixer_Audio");
1492
1493         while (!should_quit) {
1494                 AudioTask task;
1495
1496                 {
1497                         unique_lock<mutex> lock(audio_mutex);
1498                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1499                         if (should_quit) {
1500                                 return;
1501                         }
1502                         task = audio_task_queue.front();
1503                         audio_task_queue.pop();
1504                 }
1505
1506                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1507                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1508                 vector<float> samples_out = audio_mixer->get_output(
1509                         task.frame_timestamp,
1510                         task.num_samples,
1511                         rate_adjustment_policy);
1512
1513                 // Send the samples to the sound card, then add them to the output.
1514                 if (alsa) {
1515                         alsa->write(samples_out);
1516                 }
1517                 if (output_card_index != -1) {
1518                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1519                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1520                 }
1521                 video_encoder->add_audio(task.pts_int, move(samples_out));
1522         }
1523 }
1524
1525 void Mixer::release_display_frame(DisplayFrame *frame)
1526 {
1527         for (GLuint texnum : frame->temp_textures) {
1528                 resource_pool->release_2d_texture(texnum);
1529         }
1530         frame->temp_textures.clear();
1531         frame->ready_fence.reset();
1532         frame->input_frames.clear();
1533 }
1534
1535 void Mixer::start()
1536 {
1537         mixer_thread = thread(&Mixer::thread_func, this);
1538         audio_thread = thread(&Mixer::audio_thread_func, this);
1539 }
1540
1541 void Mixer::quit()
1542 {
1543         should_quit = true;
1544         audio_task_queue_changed.notify_one();
1545         mixer_thread.join();
1546         audio_thread.join();
1547 }
1548
1549 void Mixer::transition_clicked(int transition_num)
1550 {
1551         theme->transition_clicked(transition_num, pts());
1552 }
1553
1554 void Mixer::channel_clicked(int preview_num)
1555 {
1556         theme->channel_clicked(preview_num);
1557 }
1558
1559 YCbCrInterpretation Mixer::get_input_ycbcr_interpretation(unsigned card_index) const
1560 {
1561         unique_lock<mutex> lock(card_mutex);
1562         return ycbcr_interpretation[card_index];
1563 }
1564
1565 void Mixer::set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation)
1566 {
1567         unique_lock<mutex> lock(card_mutex);
1568         ycbcr_interpretation[card_index] = interpretation;
1569 }
1570
1571 void Mixer::start_mode_scanning(unsigned card_index)
1572 {
1573         assert(card_index < num_cards);
1574         if (is_mode_scanning[card_index]) {
1575                 return;
1576         }
1577         is_mode_scanning[card_index] = true;
1578         mode_scanlist[card_index].clear();
1579         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1580                 mode_scanlist[card_index].push_back(mode.first);
1581         }
1582         assert(!mode_scanlist[card_index].empty());
1583         mode_scanlist_index[card_index] = 0;
1584         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1585         last_mode_scan_change[card_index] = steady_clock::now();
1586 }
1587
1588 map<uint32_t, VideoMode> Mixer::get_available_output_video_modes() const
1589 {
1590         assert(desired_output_card_index != -1);
1591         unique_lock<mutex> lock(card_mutex);
1592         return cards[desired_output_card_index].output->get_available_video_modes();
1593 }
1594
1595 string Mixer::get_ffmpeg_filename(unsigned card_index) const
1596 {
1597         assert(card_index >= num_cards && card_index < num_cards + num_video_inputs);
1598         return ((FFmpegCapture *)(cards[card_index].capture.get()))->get_filename();
1599 }
1600
1601 void Mixer::set_ffmpeg_filename(unsigned card_index, const string &filename) {
1602         assert(card_index >= num_cards && card_index < num_cards + num_video_inputs);
1603         ((FFmpegCapture *)(cards[card_index].capture.get()))->change_filename(filename);
1604 }
1605
1606 void Mixer::wait_for_next_frame()
1607 {
1608         unique_lock<mutex> lock(frame_num_mutex);
1609         unsigned old_frame_num = frame_num;
1610         frame_num_updated.wait_for(lock, seconds(1),  // Timeout is just in case.
1611                 [old_frame_num, this]{ return this->frame_num > old_frame_num; });
1612 }
1613
1614 Mixer::OutputChannel::~OutputChannel()
1615 {
1616         if (has_current_frame) {
1617                 parent->release_display_frame(&current_frame);
1618         }
1619         if (has_ready_frame) {
1620                 parent->release_display_frame(&ready_frame);
1621         }
1622 }
1623
1624 void Mixer::OutputChannel::output_frame(DisplayFrame &&frame)
1625 {
1626         // Store this frame for display. Remove the ready frame if any
1627         // (it was seemingly never used).
1628         {
1629                 unique_lock<mutex> lock(frame_mutex);
1630                 if (has_ready_frame) {
1631                         parent->release_display_frame(&ready_frame);
1632                 }
1633                 ready_frame = move(frame);
1634                 has_ready_frame = true;
1635
1636                 // Call the callbacks under the mutex (they should be short),
1637                 // so that we don't race against a callback removal.
1638                 for (const auto &key_and_callback : new_frame_ready_callbacks) {
1639                         key_and_callback.second();
1640                 }
1641         }
1642
1643         // Reduce the number of callbacks by filtering duplicates. The reason
1644         // why we bother doing this is that Qt seemingly can get into a state
1645         // where its builds up an essentially unbounded queue of signals,
1646         // consuming more and more memory, and there's no good way of collapsing
1647         // user-defined signals or limiting the length of the queue.
1648         if (transition_names_updated_callback) {
1649                 vector<string> transition_names = global_mixer->get_transition_names();
1650                 bool changed = false;
1651                 if (transition_names.size() != last_transition_names.size()) {
1652                         changed = true;
1653                 } else {
1654                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1655                                 if (transition_names[i] != last_transition_names[i]) {
1656                                         changed = true;
1657                                         break;
1658                                 }
1659                         }
1660                 }
1661                 if (changed) {
1662                         transition_names_updated_callback(transition_names);
1663                         last_transition_names = transition_names;
1664                 }
1665         }
1666         if (name_updated_callback) {
1667                 string name = global_mixer->get_channel_name(channel);
1668                 if (name != last_name) {
1669                         name_updated_callback(name);
1670                         last_name = name;
1671                 }
1672         }
1673         if (color_updated_callback) {
1674                 string color = global_mixer->get_channel_color(channel);
1675                 if (color != last_color) {
1676                         color_updated_callback(color);
1677                         last_color = color;
1678                 }
1679         }
1680 }
1681
1682 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1683 {
1684         unique_lock<mutex> lock(frame_mutex);
1685         if (!has_current_frame && !has_ready_frame) {
1686                 return false;
1687         }
1688
1689         if (has_current_frame && has_ready_frame) {
1690                 // We have a new ready frame. Toss the current one.
1691                 parent->release_display_frame(&current_frame);
1692                 has_current_frame = false;
1693         }
1694         if (has_ready_frame) {
1695                 assert(!has_current_frame);
1696                 current_frame = move(ready_frame);
1697                 ready_frame.ready_fence.reset();  // Drop the refcount.
1698                 ready_frame.input_frames.clear();  // Drop the refcounts.
1699                 has_current_frame = true;
1700                 has_ready_frame = false;
1701         }
1702
1703         *frame = current_frame;
1704         return true;
1705 }
1706
1707 void Mixer::OutputChannel::add_frame_ready_callback(void *key, Mixer::new_frame_ready_callback_t callback)
1708 {
1709         unique_lock<mutex> lock(frame_mutex);
1710         new_frame_ready_callbacks[key] = callback;
1711 }
1712
1713 void Mixer::OutputChannel::remove_frame_ready_callback(void *key)
1714 {
1715         unique_lock<mutex> lock(frame_mutex);
1716         new_frame_ready_callbacks.erase(key);
1717 }
1718
1719 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1720 {
1721         transition_names_updated_callback = callback;
1722 }
1723
1724 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1725 {
1726         name_updated_callback = callback;
1727 }
1728
1729 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1730 {
1731         color_updated_callback = callback;
1732 }
1733
1734 mutex RefCountedGLsync::fence_lock;