]> git.sesse.net Git - nageru/blob - mixer.cpp
Fix a lock that was held too long in an edge case.
[nageru] / mixer.cpp
1 #undef Success
2
3 #include "mixer.h"
4
5 #include <assert.h>
6 #include <epoxy/egl.h>
7 #include <movit/effect_chain.h>
8 #include <movit/effect_util.h>
9 #include <movit/flat_input.h>
10 #include <movit/image_format.h>
11 #include <movit/init.h>
12 #include <movit/resource_pool.h>
13 #include <pthread.h>
14 #include <stdint.h>
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <sys/resource.h>
18 #include <algorithm>
19 #include <chrono>
20 #include <condition_variable>
21 #include <cstddef>
22 #include <cstdint>
23 #include <memory>
24 #include <mutex>
25 #include <ratio>
26 #include <string>
27 #include <thread>
28 #include <utility>
29 #include <vector>
30
31 #include "DeckLinkAPI.h"
32 #include "LinuxCOM.h"
33 #include "alsa_output.h"
34 #include "bmusb/bmusb.h"
35 #include "bmusb/fake_capture.h"
36 #include "chroma_subsampler.h"
37 #include "context.h"
38 #include "decklink_capture.h"
39 #include "decklink_output.h"
40 #include "defs.h"
41 #include "disk_space_estimator.h"
42 #include "ffmpeg_capture.h"
43 #include "flags.h"
44 #include "input_mapping.h"
45 #include "metrics.h"
46 #include "pbo_frame_allocator.h"
47 #include "ref_counted_gl_sync.h"
48 #include "resampling_queue.h"
49 #include "timebase.h"
50 #include "timecode_renderer.h"
51 #include "v210_converter.h"
52 #include "video_encoder.h"
53
54 class IDeckLink;
55 class QOpenGLContext;
56
57 using namespace movit;
58 using namespace std;
59 using namespace std::chrono;
60 using namespace std::placeholders;
61 using namespace bmusb;
62
63 Mixer *global_mixer = nullptr;
64 bool uses_mlock = false;
65
66 namespace {
67
68 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
69 {
70         if (interlaced) {
71                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
72                         input_state->buffered_frames[card_index][frame_num] =
73                                 input_state->buffered_frames[card_index][frame_num - 1];
74                 }
75                 input_state->buffered_frames[card_index][0] = { frame, field_num };
76         } else {
77                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
78                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
79                 }
80         }
81 }
82
83 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned cbcr_width, unsigned cbcr_height, unsigned v210_width)
84 {
85         bool first;
86         switch (userdata->pixel_format) {
87         case PixelFormat_10BitYCbCr:
88                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
89                 break;
90         case PixelFormat_8BitYCbCr:
91                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
92                 break;
93         case PixelFormat_8BitBGRA:
94                 first = userdata->tex_rgba[field] == 0;
95                 break;
96         case PixelFormat_8BitYCbCrPlanar:
97                 first = userdata->tex_y[field] == 0 || userdata->tex_cb[field] == 0 || userdata->tex_cr[field] == 0;
98                 break;
99         default:
100                 assert(false);
101         }
102
103         if (first ||
104             width != userdata->last_width[field] ||
105             height != userdata->last_height[field] ||
106             cbcr_width != userdata->last_cbcr_width[field] ||
107             cbcr_height != userdata->last_cbcr_height[field]) {
108                 // We changed resolution since last use of this texture, so we need to create
109                 // a new object. Note that this each card has its own PBOFrameAllocator,
110                 // we don't need to worry about these flip-flopping between resolutions.
111                 switch (userdata->pixel_format) {
112                 case PixelFormat_10BitYCbCr:
113                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
114                         check_error();
115                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
116                         check_error();
117                         break;
118                 case PixelFormat_8BitYCbCr: {
119                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
120                         check_error();
121                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
122                         check_error();
123                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
124                         check_error();
125                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
126                         check_error();
127                         break;
128                 }
129                 case PixelFormat_8BitYCbCrPlanar: {
130                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
131                         check_error();
132                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
133                         check_error();
134                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cb[field]);
135                         check_error();
136                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
137                         check_error();
138                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cr[field]);
139                         check_error();
140                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
141                         check_error();
142                         break;
143                 }
144                 case PixelFormat_8BitBGRA:
145                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
146                         check_error();
147                         if (global_flags.can_disable_srgb_decoder) {  // See the comments in tweaked_inputs.h.
148                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
149                         } else {
150                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
151                         }
152                         check_error();
153                         break;
154                 }
155                 userdata->last_width[field] = width;
156                 userdata->last_height[field] = height;
157                 userdata->last_cbcr_width[field] = cbcr_width;
158                 userdata->last_cbcr_height[field] = cbcr_height;
159         }
160         if (global_flags.ten_bit_input &&
161             (first || v210_width != userdata->last_v210_width[field])) {
162                 // Same as above; we need to recreate the texture.
163                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
164                 check_error();
165                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
166                 check_error();
167                 userdata->last_v210_width[field] = v210_width;
168         }
169 }
170
171 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
172 {
173         if (interlaced_stride) {
174                 stride *= 2;
175         }
176         if (global_flags.flush_pbos) {
177                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
178                 check_error();
179         }
180
181         glBindTexture(GL_TEXTURE_2D, tex);
182         check_error();
183         if (interlaced_stride) {
184                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
185                 check_error();
186         } else {
187                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
188                 check_error();
189         }
190
191         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
192         check_error();
193         glBindTexture(GL_TEXTURE_2D, 0);
194         check_error();
195         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
196         check_error();
197 }
198
199 }  // namespace
200
201 void QueueLengthPolicy::register_metrics(const vector<pair<string, string>> &labels)
202 {
203         global_metrics.add("input_queue_length_frames", labels, &metric_input_queue_length_frames, Metrics::TYPE_GAUGE);
204         global_metrics.add("input_queue_safe_length_frames", labels, &metric_input_queue_safe_length_frames, Metrics::TYPE_GAUGE);
205         global_metrics.add("input_queue_duped_frames", labels, &metric_input_duped_frames);
206 }
207
208 void QueueLengthPolicy::update_policy(unsigned queue_length)
209 {
210         if (queue_length == 0) {  // Starvation.
211                 if (been_at_safe_point_since_last_starvation && safe_queue_length < unsigned(global_flags.max_input_queue_frames)) {
212                         ++safe_queue_length;
213                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frame(s)\n",
214                                 card_index, safe_queue_length);
215                 }
216                 frames_with_at_least_one = 0;
217                 been_at_safe_point_since_last_starvation = false;
218                 ++metric_input_duped_frames;
219                 metric_input_queue_safe_length_frames = safe_queue_length;
220                 metric_input_queue_length_frames = 0;
221                 return;
222         }
223         if (queue_length >= safe_queue_length) {
224                 been_at_safe_point_since_last_starvation = true;
225         }
226         if (++frames_with_at_least_one >= 1000 && safe_queue_length > 1) {
227                 --safe_queue_length;
228                 metric_input_queue_safe_length_frames = safe_queue_length;
229                 fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frame(s)\n",
230                         card_index, safe_queue_length);
231                 frames_with_at_least_one = 0;
232         }
233         metric_input_queue_length_frames = min(queue_length, safe_queue_length);  // The caller will drop frames for us if needed.
234 }
235
236 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
237         : httpd(),
238           num_cards(num_cards),
239           mixer_surface(create_surface(format)),
240           h264_encoder_surface(create_surface(format)),
241           decklink_output_surface(create_surface(format)),
242           audio_mixer(num_cards)
243 {
244         memcpy(ycbcr_interpretation, global_flags.ycbcr_interpretation, sizeof(ycbcr_interpretation));
245         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
246         check_error();
247
248         // This nearly always should be true.
249         global_flags.can_disable_srgb_decoder =
250                 epoxy_has_gl_extension("GL_EXT_texture_sRGB_decode") &&
251                 epoxy_has_gl_extension("GL_ARB_sampler_objects");
252
253         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
254         // will be halved when sampling them, and we need to compensate here.
255         movit_texel_subpixel_precision /= 2.0;
256
257         resource_pool.reset(new ResourcePool);
258         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
259                 output_channel[i].parent = this;
260                 output_channel[i].channel = i;
261         }
262
263         ImageFormat inout_format;
264         inout_format.color_space = COLORSPACE_sRGB;
265         inout_format.gamma_curve = GAMMA_sRGB;
266
267         // Matches the 4:2:0 format created by the main chain.
268         YCbCrFormat ycbcr_format;
269         ycbcr_format.chroma_subsampling_x = 2;
270         ycbcr_format.chroma_subsampling_y = 2;
271         if (global_flags.ycbcr_rec709_coefficients) {
272                 ycbcr_format.luma_coefficients = YCBCR_REC_709;
273         } else {
274                 ycbcr_format.luma_coefficients = YCBCR_REC_601;
275         }
276         ycbcr_format.full_range = false;
277         ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
278         ycbcr_format.cb_x_position = 0.0f;
279         ycbcr_format.cr_x_position = 0.0f;
280         ycbcr_format.cb_y_position = 0.5f;
281         ycbcr_format.cr_y_position = 0.5f;
282
283         // Display chain; shows the live output produced by the main chain (or rather, a copy of it).
284         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
285         check_error();
286         GLenum type = global_flags.x264_bit_depth > 8 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_BYTE;
287         display_input = new YCbCrInput(inout_format, ycbcr_format, global_flags.width, global_flags.height, YCBCR_INPUT_SPLIT_Y_AND_CBCR, type);
288         display_chain->add_input(display_input);
289         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
290         display_chain->set_dither_bits(0);  // Don't bother.
291         display_chain->finalize();
292
293         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));
294
295         // Must be instantiated after VideoEncoder has initialized global_flags.use_zerocopy.
296         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
297
298         // Start listening for clients only once VideoEncoder has written its header, if any.
299         httpd.start(9095);
300
301         // First try initializing the then PCI devices, then USB, then
302         // fill up with fake cards until we have the desired number of cards.
303         unsigned num_pci_devices = 0;
304         unsigned card_index = 0;
305
306         {
307                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
308                 if (decklink_iterator != nullptr) {
309                         for ( ; card_index < num_cards; ++card_index) {
310                                 IDeckLink *decklink;
311                                 if (decklink_iterator->Next(&decklink) != S_OK) {
312                                         break;
313                                 }
314
315                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
316                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
317                                 output->set_device(decklink);
318                                 configure_card(card_index, capture, CardType::LIVE_CARD, output);
319                                 ++num_pci_devices;
320                         }
321                         decklink_iterator->Release();
322                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
323                 } else {
324                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
325                 }
326         }
327
328         unsigned num_usb_devices = BMUSBCapture::num_cards();
329         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
330                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
331                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
332                 configure_card(card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
333         }
334         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
335
336         unsigned num_fake_cards = 0;
337         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
338                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
339                 configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
340         }
341
342         if (num_fake_cards > 0) {
343                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
344         }
345
346         // Initialize all video inputs the theme asked for. Note that these are
347         // all put _after_ the regular cards, which stop at <num_cards> - 1.
348         std::vector<FFmpegCapture *> video_inputs = theme->get_video_inputs();
349         for (unsigned video_card_index = 0; video_card_index < video_inputs.size(); ++card_index, ++video_card_index) {
350                 if (card_index >= MAX_VIDEO_CARDS) {
351                         fprintf(stderr, "ERROR: Not enough card slots available for the videos the theme requested.\n");
352                         exit(1);
353                 }
354                 configure_card(card_index, video_inputs[video_card_index], CardType::FFMPEG_INPUT, /*output=*/nullptr);
355                 video_inputs[video_card_index]->set_card_index(card_index);
356         }
357         num_video_inputs = video_inputs.size();
358
359         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
360         BMUSBCapture::start_bm_thread();
361
362         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
363                 cards[card_index].queue_length_policy.reset(card_index);
364         }
365
366         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
367
368         if (global_flags.ten_bit_input) {
369                 if (!v210Converter::has_hardware_support()) {
370                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
371                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
372                         exit(1);
373                 }
374                 v210_converter.reset(new v210Converter());
375
376                 // These are all the widths listed in the Blackmagic SDK documentation
377                 // (section 2.7.3, “Display Modes”).
378                 v210_converter->precompile_shader(720);
379                 v210_converter->precompile_shader(1280);
380                 v210_converter->precompile_shader(1920);
381                 v210_converter->precompile_shader(2048);
382                 v210_converter->precompile_shader(3840);
383                 v210_converter->precompile_shader(4096);
384         }
385         if (global_flags.ten_bit_output) {
386                 if (!v210Converter::has_hardware_support()) {
387                         fprintf(stderr, "ERROR: --ten-bit-output requires support for OpenGL compute shaders\n");
388                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
389                         exit(1);
390                 }
391         }
392
393         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
394         display_timecode_in_stream = global_flags.display_timecode_in_stream;
395         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
396
397         if (global_flags.enable_alsa_output) {
398                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
399         }
400         if (global_flags.output_card != -1) {
401                 desired_output_card_index = global_flags.output_card;
402                 set_output_card_internal(global_flags.output_card);
403         }
404
405         metric_start_time_seconds = get_timestamp_for_metrics();
406
407         global_metrics.add("frames_output_total", &metric_frames_output_total);
408         global_metrics.add("frames_output_dropped", &metric_frames_output_dropped);
409         global_metrics.add("start_time_seconds", &metric_start_time_seconds, Metrics::TYPE_GAUGE);
410         global_metrics.add("memory_used_bytes", &metrics_memory_used_bytes);
411         global_metrics.add("memory_locked_limit_bytes", &metrics_memory_locked_limit_bytes);
412 }
413
414 Mixer::~Mixer()
415 {
416         BMUSBCapture::stop_bm_thread();
417
418         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
419                 {
420                         unique_lock<mutex> lock(card_mutex);
421                         cards[card_index].should_quit = true;  // Unblock thread.
422                         cards[card_index].new_frames_changed.notify_all();
423                 }
424                 cards[card_index].capture->stop_dequeue_thread();
425                 if (cards[card_index].output) {
426                         cards[card_index].output->end_output();
427                         cards[card_index].output.reset();
428                 }
429         }
430
431         video_encoder.reset(nullptr);
432 }
433
434 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, CardType card_type, DeckLinkOutput *output)
435 {
436         printf("Configuring card %d...\n", card_index);
437
438         CaptureCard *card = &cards[card_index];
439         if (card->capture != nullptr) {
440                 card->capture->stop_dequeue_thread();
441         }
442         card->capture.reset(capture);
443         card->is_fake_capture = (card_type == CardType::FAKE_CAPTURE);
444         card->type = card_type;
445         if (card->output.get() != output) {
446                 card->output.reset(output);
447         }
448
449         PixelFormat pixel_format;
450         if (card_type == CardType::FFMPEG_INPUT) {
451                 pixel_format = capture->get_current_pixel_format();
452         } else if (global_flags.ten_bit_input) {
453                 pixel_format = PixelFormat_10BitYCbCr;
454         } else {
455                 pixel_format = PixelFormat_8BitYCbCr;
456         }
457
458         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
459         if (card->frame_allocator == nullptr) {
460                 card->frame_allocator.reset(new PBOFrameAllocator(pixel_format, 8 << 20, global_flags.width, global_flags.height));  // 8 MB.
461         }
462         card->capture->set_video_frame_allocator(card->frame_allocator.get());
463         if (card->surface == nullptr) {
464                 card->surface = create_surface_with_same_format(mixer_surface);
465         }
466         while (!card->new_frames.empty()) card->new_frames.pop_front();
467         card->last_timecode = -1;
468         card->capture->set_pixel_format(pixel_format);
469         card->capture->configure_card();
470
471         // NOTE: start_bm_capture() happens in thread_func().
472
473         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
474         audio_mixer.reset_resampler(device);
475         audio_mixer.set_display_name(device, card->capture->get_description());
476         audio_mixer.trigger_state_changed_callback();
477
478         // Register metrics.
479         vector<pair<string, string>> labels;
480         char card_name[64];
481         snprintf(card_name, sizeof(card_name), "%d", card_index);
482         labels.emplace_back("card", card_name);
483
484         switch (card_type) {
485         case CardType::LIVE_CARD:
486                 labels.emplace_back("cardtype", "live");
487                 break;
488         case CardType::FAKE_CAPTURE:
489                 labels.emplace_back("cardtype", "fake");
490                 break;
491         case CardType::FFMPEG_INPUT:
492                 labels.emplace_back("cardtype", "ffmpeg");
493                 break;
494         default:
495                 assert(false);
496         }
497         card->queue_length_policy.register_metrics(labels);
498         global_metrics.add("input_received_frames", labels, &card->metric_input_received_frames);
499         global_metrics.add("input_dropped_frames_jitter", labels, &card->metric_input_dropped_frames_jitter);
500         global_metrics.add("input_dropped_frames_error", labels, &card->metric_input_dropped_frames_error);
501         global_metrics.add("input_dropped_frames_resets", labels, &card->metric_input_resets);
502
503         global_metrics.add("input_has_signal_bool", labels, &card->metric_input_has_signal_bool, Metrics::TYPE_GAUGE);
504         global_metrics.add("input_is_connected_bool", labels, &card->metric_input_is_connected_bool, Metrics::TYPE_GAUGE);
505         global_metrics.add("input_interlaced_bool", labels, &card->metric_input_interlaced_bool, Metrics::TYPE_GAUGE);
506         global_metrics.add("input_width_pixels", labels, &card->metric_input_width_pixels, Metrics::TYPE_GAUGE);
507         global_metrics.add("input_height_pixels", labels, &card->metric_input_height_pixels, Metrics::TYPE_GAUGE);
508         global_metrics.add("input_frame_rate_nom", labels, &card->metric_input_frame_rate_nom, Metrics::TYPE_GAUGE);
509         global_metrics.add("input_frame_rate_den", labels, &card->metric_input_frame_rate_den, Metrics::TYPE_GAUGE);
510         global_metrics.add("input_sample_rate_hz", labels, &card->metric_input_sample_rate_hz, Metrics::TYPE_GAUGE);
511 }
512
513 void Mixer::set_output_card_internal(int card_index)
514 {
515         // We don't really need to take card_mutex, since we're in the mixer
516         // thread and don't mess with any queues (which is the only thing that happens
517         // from other threads), but it's probably the safest in the long run.
518         unique_lock<mutex> lock(card_mutex);
519         if (output_card_index != -1) {
520                 // Switch the old card from output to input.
521                 CaptureCard *old_card = &cards[output_card_index];
522                 old_card->output->end_output();
523
524                 // Stop the fake card that we put into place.
525                 // This needs to _not_ happen under the mutex, to avoid deadlock
526                 // (delivering the last frame needs to take the mutex).
527                 CaptureInterface *fake_capture = old_card->capture.get();
528                 lock.unlock();
529                 fake_capture->stop_dequeue_thread();
530                 lock.lock();
531                 old_card->capture = move(old_card->parked_capture);
532                 old_card->is_fake_capture = false;
533                 old_card->capture->start_bm_capture();
534         }
535         if (card_index != -1) {
536                 CaptureCard *card = &cards[card_index];
537                 CaptureInterface *capture = card->capture.get();
538                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
539                 // several seconds to complete (blocking on DisableVideoInput);
540                 // see if we can maybe do it asynchronously.
541                 lock.unlock();
542                 capture->stop_dequeue_thread();
543                 lock.lock();
544                 card->parked_capture = move(card->capture);
545                 CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
546                 configure_card(card_index, fake_capture, CardType::FAKE_CAPTURE, card->output.release());
547                 card->queue_length_policy.reset(card_index);
548                 card->capture->start_bm_capture();
549                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
550                 card->output->start_output(desired_output_video_mode, pts_int);
551         }
552         output_card_index = card_index;
553 }
554
555 namespace {
556
557 int unwrap_timecode(uint16_t current_wrapped, int last)
558 {
559         uint16_t last_wrapped = last & 0xffff;
560         if (current_wrapped > last_wrapped) {
561                 return (last & ~0xffff) | current_wrapped;
562         } else {
563                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
564         }
565 }
566
567 }  // namespace
568
569 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
570                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
571                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
572 {
573         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
574         CaptureCard *card = &cards[card_index];
575
576         ++card->metric_input_received_frames;
577         card->metric_input_has_signal_bool = video_format.has_signal;
578         card->metric_input_is_connected_bool = video_format.is_connected;
579         card->metric_input_interlaced_bool = video_format.interlaced;
580         card->metric_input_width_pixels = video_format.width;
581         card->metric_input_height_pixels = video_format.height;
582         card->metric_input_frame_rate_nom = video_format.frame_rate_nom;
583         card->metric_input_frame_rate_den = video_format.frame_rate_den;
584         card->metric_input_sample_rate_hz = audio_format.sample_rate;
585
586         if (is_mode_scanning[card_index]) {
587                 if (video_format.has_signal) {
588                         // Found a stable signal, so stop scanning.
589                         is_mode_scanning[card_index] = false;
590                 } else {
591                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
592                         steady_clock::time_point now = steady_clock::now();
593                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
594                         if (sec_since_last_switch > switch_time_s) {
595                                 // It isn't this mode; try the next one.
596                                 mode_scanlist_index[card_index]++;
597                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
598                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
599                                 last_mode_scan_change[card_index] = now;
600                         }
601                 }
602         }
603
604         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
605         assert(frame_length > 0);
606
607         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;
608         if (num_samples > OUTPUT_FREQUENCY / 10) {
609                 printf("Card %d: Dropping frame with implausible audio length (len=%d, offset=%d) [timecode=0x%04x video_len=%d video_offset=%d video_format=%x)\n",
610                         card_index, int(audio_frame.len), int(audio_offset),
611                         timecode, int(video_frame.len), int(video_offset), video_format.id);
612                 if (video_frame.owner) {
613                         video_frame.owner->release_frame(video_frame);
614                 }
615                 if (audio_frame.owner) {
616                         audio_frame.owner->release_frame(audio_frame);
617                 }
618                 return;
619         }
620
621         int dropped_frames = 0;
622         if (card->last_timecode != -1) {
623                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
624         }
625
626         // Number of samples per frame if we need to insert silence.
627         // (Could be nonintegral, but resampling will save us then.)
628         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
629
630         if (dropped_frames > MAX_FPS * 2) {
631                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
632                         card_index, card->last_timecode, timecode);
633                 audio_mixer.reset_resampler(device);
634                 dropped_frames = 0;
635                 ++card->metric_input_resets;
636         } else if (dropped_frames > 0) {
637                 // Insert silence as needed.
638                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
639                         card_index, dropped_frames, timecode);
640                 card->metric_input_dropped_frames_error += dropped_frames;
641
642                 bool success;
643                 do {
644                         success = audio_mixer.add_silence(device, silence_samples, dropped_frames, frame_length);
645                 } while (!success);
646         }
647
648         audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
649
650         // Done with the audio, so release it.
651         if (audio_frame.owner) {
652                 audio_frame.owner->release_frame(audio_frame);
653         }
654
655         card->last_timecode = timecode;
656
657         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
658
659         size_t cbcr_width, cbcr_height, cbcr_offset, y_offset;
660         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
661         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
662                 // The calculation above is wrong for planar Y'CbCr, so just override it.
663                 assert(card->type == CardType::FFMPEG_INPUT);
664                 assert(video_offset == 0);
665                 expected_length = video_frame.len;
666
667                 userdata->ycbcr_format = (static_cast<FFmpegCapture *>(card->capture.get()))->get_current_frame_ycbcr_format();
668                 cbcr_width = video_format.width / userdata->ycbcr_format.chroma_subsampling_x;
669                 cbcr_height = video_format.height / userdata->ycbcr_format.chroma_subsampling_y;
670                 cbcr_offset = video_format.width * video_format.height;
671                 y_offset = 0;
672         } else {
673                 // All the other Y'CbCr formats are 4:2:2.
674                 cbcr_width = video_format.width / 2;
675                 cbcr_height = video_format.height;
676                 cbcr_offset = video_offset / 2;
677                 y_offset = video_frame.size / 2 + video_offset / 2;
678         }
679         if (video_frame.len - video_offset == 0 ||
680             video_frame.len - video_offset != expected_length) {
681                 if (video_frame.len != 0) {
682                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
683                                 card_index, video_frame.len - video_offset, expected_length);
684                 }
685                 if (video_frame.owner) {
686                         video_frame.owner->release_frame(video_frame);
687                 }
688
689                 // Still send on the information that we _had_ a frame, even though it's corrupted,
690                 // so that pts can go up accordingly.
691                 {
692                         unique_lock<mutex> lock(card_mutex);
693                         CaptureCard::NewFrame new_frame;
694                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
695                         new_frame.length = frame_length;
696                         new_frame.interlaced = false;
697                         new_frame.dropped_frames = dropped_frames;
698                         new_frame.received_timestamp = video_frame.received_timestamp;
699                         card->new_frames.push_back(move(new_frame));
700                         card->new_frames_changed.notify_all();
701                 }
702                 return;
703         }
704
705         unsigned num_fields = video_format.interlaced ? 2 : 1;
706         steady_clock::time_point frame_upload_start;
707         bool interlaced_stride = false;
708         if (video_format.interlaced) {
709                 // Send the two fields along as separate frames; the other side will need to add
710                 // a deinterlacer to actually get this right.
711                 assert(video_format.height % 2 == 0);
712                 video_format.height /= 2;
713                 cbcr_height /= 2;
714                 assert(frame_length % 2 == 0);
715                 frame_length /= 2;
716                 num_fields = 2;
717                 if (video_format.second_field_start == 1) {
718                         interlaced_stride = true;
719                 }
720                 frame_upload_start = steady_clock::now();
721         }
722         userdata->last_interlaced = video_format.interlaced;
723         userdata->last_has_signal = video_format.has_signal;
724         userdata->last_is_connected = video_format.is_connected;
725         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
726         userdata->last_frame_rate_den = video_format.frame_rate_den;
727         RefCountedFrame frame(video_frame);
728
729         // Upload the textures.
730         for (unsigned field = 0; field < num_fields; ++field) {
731                 // Put the actual texture upload in a lambda that is executed in the main thread.
732                 // It is entirely possible to do this in the same thread (and it might even be
733                 // faster, depending on the GPU and driver), but it appears to be trickling
734                 // driver bugs very easily.
735                 //
736                 // Note that this means we must hold on to the actual frame data in <userdata>
737                 // until the upload command is run, but we hold on to <frame> much longer than that
738                 // (in fact, all the way until we no longer use the texture in rendering).
739                 auto upload_func = [this, field, video_format, y_offset, video_offset, cbcr_offset, cbcr_width, cbcr_height, interlaced_stride, userdata]() {
740                         unsigned field_start_line;
741                         if (field == 1) {
742                                 field_start_line = video_format.second_field_start;
743                         } else {
744                                 field_start_line = video_format.extra_lines_top;
745                         }
746
747                         // For anything not FRAME_FORMAT_YCBCR_10BIT, v210_width will be nonsensical but not used.
748                         size_t v210_width = video_format.stride / sizeof(uint32_t);
749                         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, cbcr_width, cbcr_height, v210_width);
750
751                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
752                         check_error();
753
754                         switch (userdata->pixel_format) {
755                         case PixelFormat_10BitYCbCr: {
756                                 size_t field_start = video_offset + video_format.stride * field_start_line;
757                                 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);
758                                 v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
759                                 break;
760                         }
761                         case PixelFormat_8BitYCbCr: {
762                                 size_t field_y_start = y_offset + video_format.width * field_start_line;
763                                 size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
764
765                                 // Make up our own strides, since we are interleaving.
766                                 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);
767                                 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);
768                                 break;
769                         }
770                         case PixelFormat_8BitYCbCrPlanar: {
771                                 assert(field_start_line == 0);  // We don't really support interlaced here.
772                                 size_t field_y_start = y_offset;
773                                 size_t field_cb_start = cbcr_offset;
774                                 size_t field_cr_start = cbcr_offset + cbcr_width * cbcr_height;
775
776                                 // Make up our own strides, since we are interleaving.
777                                 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);
778                                 upload_texture(userdata->tex_cb[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cb_start);
779                                 upload_texture(userdata->tex_cr[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cr_start);
780                                 break;
781                         }
782                         case PixelFormat_8BitBGRA: {
783                                 size_t field_start = video_offset + video_format.stride * field_start_line;
784                                 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);
785                                 // These could be asked to deliver mipmaps at any time.
786                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
787                                 check_error();
788                                 glGenerateMipmap(GL_TEXTURE_2D);
789                                 check_error();
790                                 glBindTexture(GL_TEXTURE_2D, 0);
791                                 check_error();
792                                 break;
793                         }
794                         default:
795                                 assert(false);
796                         }
797
798                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
799                         check_error();
800                 };
801
802                 if (field == 1) {
803                         // Don't upload the second field as fast as we can; wait until
804                         // the field time has approximately passed. (Otherwise, we could
805                         // get timing jitter against the other sources, and possibly also
806                         // against the video display, although the latter is not as critical.)
807                         // This requires our system clock to be reasonably close to the
808                         // video clock, but that's not an unreasonable assumption.
809                         steady_clock::time_point second_field_start = frame_upload_start +
810                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
811                         this_thread::sleep_until(second_field_start);
812                 }
813
814                 {
815                         unique_lock<mutex> lock(card_mutex);
816                         CaptureCard::NewFrame new_frame;
817                         new_frame.frame = frame;
818                         new_frame.length = frame_length;
819                         new_frame.field = field;
820                         new_frame.interlaced = video_format.interlaced;
821                         new_frame.upload_func = upload_func;
822                         new_frame.dropped_frames = dropped_frames;
823                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
824                         card->new_frames.push_back(move(new_frame));
825                         card->new_frames_changed.notify_all();
826                 }
827         }
828 }
829
830 void Mixer::bm_hotplug_add(libusb_device *dev)
831 {
832         lock_guard<mutex> lock(hotplug_mutex);
833         hotplugged_cards.push_back(dev);
834 }
835
836 void Mixer::bm_hotplug_remove(unsigned card_index)
837 {
838         cards[card_index].new_frames_changed.notify_all();
839 }
840
841 void Mixer::thread_func()
842 {
843         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
844
845         eglBindAPI(EGL_OPENGL_API);
846         QOpenGLContext *context = create_context(mixer_surface);
847         if (!make_current(context, mixer_surface)) {
848                 printf("oops\n");
849                 exit(1);
850         }
851
852         // Start the actual capture. (We don't want to do it before we're actually ready
853         // to process output frames.)
854         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
855                 if (int(card_index) != output_card_index) {
856                         cards[card_index].capture->start_bm_capture();
857                 }
858         }
859
860         steady_clock::time_point start, now;
861         start = steady_clock::now();
862
863         int stats_dropped_frames = 0;
864
865         while (!should_quit) {
866                 if (desired_output_card_index != output_card_index) {
867                         set_output_card_internal(desired_output_card_index);
868                 }
869                 if (output_card_index != -1 &&
870                     desired_output_video_mode != output_video_mode) {
871                         DeckLinkOutput *output = cards[output_card_index].output.get();
872                         output->end_output();
873                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
874                         output->start_output(desired_output_video_mode, pts_int);
875                 }
876
877                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
878                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
879
880                 bool master_card_is_output;
881                 unsigned master_card_index;
882                 if (output_card_index != -1) {
883                         master_card_is_output = true;
884                         master_card_index = output_card_index;
885                 } else {
886                         master_card_is_output = false;
887                         master_card_index = theme->map_signal(master_clock_channel);
888                         assert(master_card_index < num_cards);
889                 }
890
891                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
892                 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);
893                 stats_dropped_frames += output_frame_info.dropped_frames;
894
895                 handle_hotplugged_cards();
896
897                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
898                         if (card_index == master_card_index || !has_new_frame[card_index]) {
899                                 continue;
900                         }
901                         if (new_frames[card_index].frame->len == 0) {
902                                 ++new_frames[card_index].dropped_frames;
903                         }
904                         if (new_frames[card_index].dropped_frames > 0) {
905                                 printf("Card %u dropped %d frames before this\n",
906                                         card_index, int(new_frames[card_index].dropped_frames));
907                         }
908                 }
909
910                 // If the first card is reporting a corrupted or otherwise dropped frame,
911                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
912                 if (!master_card_is_output && new_frames[master_card_index].frame->len == 0) {
913                         ++stats_dropped_frames;
914                         pts_int += new_frames[master_card_index].length;
915                         continue;
916                 }
917
918                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
919                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
920                                 continue;
921
922                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
923                         assert(new_frame->frame != nullptr);
924                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
925                         check_error();
926
927                         // The new texture might need uploading before use.
928                         if (new_frame->upload_func) {
929                                 new_frame->upload_func();
930                                 new_frame->upload_func = nullptr;
931                         }
932                 }
933
934                 int64_t frame_duration = output_frame_info.frame_duration;
935                 render_one_frame(frame_duration);
936                 ++frame_num;
937                 pts_int += frame_duration;
938
939                 now = steady_clock::now();
940                 double elapsed = duration<double>(now - start).count();
941
942                 metric_frames_output_total = frame_num;
943                 metric_frames_output_dropped = stats_dropped_frames;
944
945                 if (frame_num % 100 == 0) {
946                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
947                                 frame_num, stats_dropped_frames, elapsed, frame_num / elapsed,
948                                 1e3 * elapsed / frame_num);
949                 //      chain->print_phase_timing();
950
951                         // Check our memory usage, to see if we are close to our mlockall()
952                         // limit (if at all set).
953                         rusage used;
954                         if (getrusage(RUSAGE_SELF, &used) == -1) {
955                                 perror("getrusage(RUSAGE_SELF)");
956                                 assert(false);
957                         }
958
959                         if (uses_mlock) {
960                                 rlimit limit;
961                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
962                                         perror("getrlimit(RLIMIT_MEMLOCK)");
963                                         assert(false);
964                                 }
965
966                                 if (limit.rlim_cur == 0) {
967                                         printf(", using %ld MB memory (locked)",
968                                                 long(used.ru_maxrss / 1024));
969                                 } else {
970                                         printf(", using %ld / %ld MB lockable memory (%.1f%%)",
971                                                 long(used.ru_maxrss / 1024),
972                                                 long(limit.rlim_cur / 1048576),
973                                                 float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
974                                 }
975                                 metrics_memory_locked_limit_bytes = limit.rlim_cur;
976                         } else {
977                                 printf(", using %ld MB memory (not locked)",
978                                         long(used.ru_maxrss / 1024));
979                                 metrics_memory_locked_limit_bytes = 0.0 / 0.0;
980                         }
981
982                         printf("\n");
983
984                         metrics_memory_used_bytes = used.ru_maxrss * 1024;
985                 }
986
987
988                 if (should_cut.exchange(false)) {  // Test and clear.
989                         video_encoder->do_cut(frame_num);
990                 }
991
992 #if 0
993                 // Reset every 100 frames, so that local variations in frame times
994                 // (especially for the first few frames, when the shaders are
995                 // compiled etc.) don't make it hard to measure for the entire
996                 // remaining duration of the program.
997                 if (frame == 10000) {
998                         frame = 0;
999                         start = now;
1000                 }
1001 #endif
1002                 check_error();
1003         }
1004
1005         resource_pool->clean_context();
1006 }
1007
1008 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
1009 {
1010         if (output_card_index != -1) {
1011                 // The output card (ie., cards[output_card_index].output) is the master clock,
1012                 // so no input card (ie., cards[card_index].capture) is.
1013                 return false;
1014         }
1015         return (card_index == master_card_index);
1016 }
1017
1018 void Mixer::trim_queue(CaptureCard *card, unsigned card_index)
1019 {
1020         // Count the number of frames in the queue, including any frames
1021         // we dropped. It's hard to know exactly how we should deal with
1022         // dropped (corrupted) input frames; they don't help our goal of
1023         // avoiding starvation, but they still add to the problem of latency.
1024         // Since dropped frames is going to mean a bump in the signal anyway,
1025         // we err on the side of having more stable latency instead.
1026         unsigned queue_length = 0;
1027         for (const CaptureCard::NewFrame &frame : card->new_frames) {
1028                 queue_length += frame.dropped_frames + 1;
1029         }
1030         card->queue_length_policy.update_policy(queue_length);
1031
1032         // If needed, drop frames until the queue is below the safe limit.
1033         // We prefer to drop from the head, because all else being equal,
1034         // we'd like more recent frames (less latency).
1035         unsigned dropped_frames = 0;
1036         while (queue_length > card->queue_length_policy.get_safe_queue_length()) {
1037                 assert(!card->new_frames.empty());
1038                 assert(queue_length > card->new_frames.front().dropped_frames);
1039                 queue_length -= card->new_frames.front().dropped_frames;
1040
1041                 if (queue_length <= card->queue_length_policy.get_safe_queue_length()) {
1042                         // No need to drop anything.
1043                         break;
1044                 }
1045
1046                 card->new_frames.pop_front();
1047                 card->new_frames_changed.notify_all();
1048                 --queue_length;
1049                 ++dropped_frames;
1050         }
1051
1052         card->metric_input_dropped_frames_jitter += dropped_frames;
1053
1054 #if 0
1055         if (dropped_frames > 0) {
1056                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
1057                         card_index, dropped_frames);
1058         }
1059 #endif
1060 }
1061
1062
1063 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])
1064 {
1065         OutputFrameInfo output_frame_info;
1066 start:
1067         unique_lock<mutex> lock(card_mutex, defer_lock);
1068         if (master_card_is_output) {
1069                 // Clocked to the output, so wait for it to be ready for the next frame.
1070                 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);
1071                 lock.lock();
1072         } else {
1073                 // Wait for the master card to have a new frame.
1074                 // TODO: Add a timeout.
1075                 output_frame_info.is_preroll = false;
1076                 lock.lock();
1077                 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(); });
1078         }
1079
1080         if (master_card_is_output) {
1081                 handle_hotplugged_cards();
1082         } else if (cards[master_card_index].new_frames.empty()) {
1083                 // We were woken up, but not due to a new frame. Deal with it
1084                 // and then restart.
1085                 assert(cards[master_card_index].capture->get_disconnected());
1086                 handle_hotplugged_cards();
1087                 lock.unlock();
1088                 goto start;
1089         }
1090
1091         if (!master_card_is_output) {
1092                 output_frame_info.frame_timestamp =
1093                         cards[master_card_index].new_frames.front().received_timestamp;
1094         }
1095
1096         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
1097                 CaptureCard *card = &cards[card_index];
1098                 if (input_card_is_master_clock(card_index, master_card_index)) {
1099                         // We don't use the queue length policy for the master card,
1100                         // but we will if it stops being the master. Thus, clear out
1101                         // the policy in case we switch in the future.
1102                         card->queue_length_policy.reset(card_index);
1103                         assert(!card->new_frames.empty());
1104                 } else {
1105                         trim_queue(card, card_index);
1106                 }
1107                 if (!card->new_frames.empty()) {
1108                         new_frames[card_index] = move(card->new_frames.front());
1109                         has_new_frame[card_index] = true;
1110                         card->new_frames.pop_front();
1111                         card->new_frames_changed.notify_all();
1112                 }
1113         }
1114
1115         if (!master_card_is_output) {
1116                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
1117                 output_frame_info.frame_duration = new_frames[master_card_index].length;
1118         }
1119
1120         // This might get off by a fractional sample when changing master card
1121         // between ones with different frame rates, but that's fine.
1122         int num_samples_times_timebase = OUTPUT_FREQUENCY * output_frame_info.frame_duration + fractional_samples;
1123         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
1124         fractional_samples = num_samples_times_timebase % TIMEBASE;
1125         assert(output_frame_info.num_samples >= 0);
1126
1127         return output_frame_info;
1128 }
1129
1130 void Mixer::handle_hotplugged_cards()
1131 {
1132         // Check for cards that have been disconnected since last frame.
1133         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1134                 CaptureCard *card = &cards[card_index];
1135                 if (card->capture->get_disconnected()) {
1136                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
1137                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1138                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
1139                         card->queue_length_policy.reset(card_index);
1140                         card->capture->start_bm_capture();
1141                 }
1142         }
1143
1144         // Check for cards that have been connected since last frame.
1145         vector<libusb_device *> hotplugged_cards_copy;
1146         {
1147                 lock_guard<mutex> lock(hotplug_mutex);
1148                 swap(hotplugged_cards, hotplugged_cards_copy);
1149         }
1150         for (libusb_device *new_dev : hotplugged_cards_copy) {
1151                 // Look for a fake capture card where we can stick this in.
1152                 int free_card_index = -1;
1153                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1154                         if (cards[card_index].is_fake_capture) {
1155                                 free_card_index = card_index;
1156                                 break;
1157                         }
1158                 }
1159
1160                 if (free_card_index == -1) {
1161                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
1162                         libusb_unref_device(new_dev);
1163                 } else {
1164                         // BMUSBCapture takes ownership.
1165                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
1166                         CaptureCard *card = &cards[free_card_index];
1167                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
1168                         configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
1169                         card->queue_length_policy.reset(free_card_index);
1170                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1171                         capture->start_bm_capture();
1172                 }
1173         }
1174 }
1175
1176
1177 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)
1178 {
1179         // Resample the audio as needed, including from previously dropped frames.
1180         assert(num_cards > 0);
1181         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
1182                 const bool dropped_frame = (frame_num != dropped_frames);
1183                 {
1184                         // Signal to the audio thread to process this frame.
1185                         // Note that if the frame is a dropped frame, we signal that
1186                         // we don't want to use this frame as base for adjusting
1187                         // the resampler rate. The reason for this is that the timing
1188                         // of these frames is often way too late; they typically don't
1189                         // “arrive” before we synthesize them. Thus, we could end up
1190                         // in a situation where we have inserted e.g. five audio frames
1191                         // into the queue before we then start pulling five of them
1192                         // back out. This makes ResamplingQueue overestimate the delay,
1193                         // causing undue resampler changes. (We _do_ use the last,
1194                         // non-dropped frame; perhaps we should just discard that as well,
1195                         // since dropped frames are expected to be rare, and it might be
1196                         // better to just wait until we have a slightly more normal situation).
1197                         unique_lock<mutex> lock(audio_mutex);
1198                         bool adjust_rate = !dropped_frame && !is_preroll;
1199                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
1200                         audio_task_queue_changed.notify_one();
1201                 }
1202                 if (dropped_frame) {
1203                         // For dropped frames, increase the pts. Note that if the format changed
1204                         // in the meantime, we have no way of detecting that; we just have to
1205                         // assume the frame length is always the same.
1206                         pts_int += length_per_frame;
1207                 }
1208         }
1209 }
1210
1211 void Mixer::render_one_frame(int64_t duration)
1212 {
1213         // Determine the time code for this frame before we start rendering.
1214         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1215         if (display_timecode_on_stdout) {
1216                 printf("Timecode: '%s'\n", timecode_text.c_str());
1217         }
1218
1219         // Update Y'CbCr settings for all cards.
1220         {
1221                 unique_lock<mutex> lock(card_mutex);
1222                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1223                         YCbCrInterpretation *interpretation = &ycbcr_interpretation[card_index];
1224                         input_state.ycbcr_coefficients_auto[card_index] = interpretation->ycbcr_coefficients_auto;
1225                         input_state.ycbcr_coefficients[card_index] = interpretation->ycbcr_coefficients;
1226                         input_state.full_range[card_index] = interpretation->full_range;
1227                 }
1228         }
1229
1230         // Get the main chain from the theme, and set its state immediately.
1231         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1232         EffectChain *chain = theme_main_chain.chain;
1233         theme_main_chain.setup_chain();
1234         //theme_main_chain.chain->enable_phase_timing(true);
1235
1236         // The theme can't (or at least shouldn't!) call connect_signal() on
1237         // each FFmpeg input, so we'll do it here.
1238         for (const pair<LiveInputWrapper *, FFmpegCapture *> &conn : theme->get_signal_connections()) {
1239                 conn.first->connect_signal_raw(conn.second->get_card_index());
1240         }
1241
1242         // If HDMI/SDI output is active and the user has requested auto mode,
1243         // its mode overrides the existing Y'CbCr setting for the chain.
1244         YCbCrLumaCoefficients ycbcr_output_coefficients;
1245         if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
1246                 ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
1247         } else {
1248                 ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
1249         }
1250
1251         // TODO: Reduce the duplication against theme.cpp.
1252         YCbCrFormat output_ycbcr_format;
1253         output_ycbcr_format.chroma_subsampling_x = 1;
1254         output_ycbcr_format.chroma_subsampling_y = 1;
1255         output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
1256         output_ycbcr_format.full_range = false;
1257         output_ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
1258         chain->change_ycbcr_output_format(output_ycbcr_format);
1259
1260         // Render main chain. If we're using zerocopy Quick Sync encoding
1261         // (the default case), we take an extra copy of the created outputs,
1262         // so that we can display it back to the screen later (it's less memory
1263         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1264         // Ideally, we'd like to avoid taking copies and just use the main textures
1265         // for display as well, but they're just views into VA-API memory and must be
1266         // unmapped during encoding, so we can't use them for display, unfortunately.
1267         GLuint y_tex, cbcr_full_tex, cbcr_tex;
1268         GLuint y_copy_tex, cbcr_copy_tex = 0;
1269         GLuint y_display_tex, cbcr_display_tex;
1270         GLenum y_type = (global_flags.x264_bit_depth > 8) ? GL_R16 : GL_R8;
1271         GLenum cbcr_type = (global_flags.x264_bit_depth > 8) ? GL_RG16 : GL_RG8;
1272         const bool is_zerocopy = video_encoder->is_zerocopy();
1273         if (is_zerocopy) {
1274                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1275                 y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1276                 cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1277
1278                 y_display_tex = y_copy_tex;
1279                 cbcr_display_tex = cbcr_copy_tex;
1280
1281                 // y_tex and cbcr_tex will be given by VideoEncoder.
1282         } else {
1283                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1284                 y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1285                 cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1286
1287                 y_display_tex = y_tex;
1288                 cbcr_display_tex = cbcr_tex;
1289         }
1290
1291         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1292         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1293         assert(got_frame);
1294
1295         GLuint fbo;
1296         if (is_zerocopy) {
1297                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1298         } else {
1299                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
1300         }
1301         check_error();
1302         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1303
1304         if (display_timecode_in_stream) {
1305                 // Render the timecode on top.
1306                 timecode_renderer->render_timecode(fbo, timecode_text);
1307         }
1308
1309         resource_pool->release_fbo(fbo);
1310
1311         if (is_zerocopy) {
1312                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1313         } else {
1314                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1315         }
1316         if (output_card_index != -1) {
1317                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
1318         }
1319         resource_pool->release_2d_texture(cbcr_full_tex);
1320
1321         // Set the right state for the Y' and CbCr textures we use for display.
1322         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1323         glBindTexture(GL_TEXTURE_2D, y_display_tex);
1324         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1325         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1326         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1327
1328         glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
1329         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1330         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1331         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1332
1333         RefCountedGLsync fence = video_encoder->end_frame();
1334
1335         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1336         // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
1337         DisplayFrame live_frame;
1338         live_frame.chain = display_chain.get();
1339         live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
1340                 display_input->set_texture_num(0, y_display_tex);
1341                 display_input->set_texture_num(1, cbcr_display_tex);
1342         };
1343         live_frame.ready_fence = fence;
1344         live_frame.input_frames = {};
1345         live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
1346         output_channel[OUTPUT_LIVE].output_frame(live_frame);
1347
1348         // Set up preview and any additional channels.
1349         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1350                 DisplayFrame display_frame;
1351                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1352                 display_frame.chain = chain.chain;
1353                 display_frame.setup_chain = chain.setup_chain;
1354                 display_frame.ready_fence = fence;
1355                 display_frame.input_frames = chain.input_frames;
1356                 display_frame.temp_textures = {};
1357                 output_channel[i].output_frame(display_frame);
1358         }
1359 }
1360
1361 void Mixer::audio_thread_func()
1362 {
1363         pthread_setname_np(pthread_self(), "Mixer_Audio");
1364
1365         while (!should_quit) {
1366                 AudioTask task;
1367
1368                 {
1369                         unique_lock<mutex> lock(audio_mutex);
1370                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1371                         if (should_quit) {
1372                                 return;
1373                         }
1374                         task = audio_task_queue.front();
1375                         audio_task_queue.pop();
1376                 }
1377
1378                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1379                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1380                 vector<float> samples_out = audio_mixer.get_output(
1381                         task.frame_timestamp,
1382                         task.num_samples,
1383                         rate_adjustment_policy);
1384
1385                 // Send the samples to the sound card, then add them to the output.
1386                 if (alsa) {
1387                         alsa->write(samples_out);
1388                 }
1389                 if (output_card_index != -1) {
1390                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1391                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1392                 }
1393                 video_encoder->add_audio(task.pts_int, move(samples_out));
1394         }
1395 }
1396
1397 void Mixer::release_display_frame(DisplayFrame *frame)
1398 {
1399         for (GLuint texnum : frame->temp_textures) {
1400                 resource_pool->release_2d_texture(texnum);
1401         }
1402         frame->temp_textures.clear();
1403         frame->ready_fence.reset();
1404         frame->input_frames.clear();
1405 }
1406
1407 void Mixer::start()
1408 {
1409         mixer_thread = thread(&Mixer::thread_func, this);
1410         audio_thread = thread(&Mixer::audio_thread_func, this);
1411 }
1412
1413 void Mixer::quit()
1414 {
1415         should_quit = true;
1416         audio_task_queue_changed.notify_one();
1417         mixer_thread.join();
1418         audio_thread.join();
1419 }
1420
1421 void Mixer::transition_clicked(int transition_num)
1422 {
1423         theme->transition_clicked(transition_num, pts());
1424 }
1425
1426 void Mixer::channel_clicked(int preview_num)
1427 {
1428         theme->channel_clicked(preview_num);
1429 }
1430
1431 YCbCrInterpretation Mixer::get_input_ycbcr_interpretation(unsigned card_index) const
1432 {
1433         unique_lock<mutex> lock(card_mutex);
1434         return ycbcr_interpretation[card_index];
1435 }
1436
1437 void Mixer::set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation)
1438 {
1439         unique_lock<mutex> lock(card_mutex);
1440         ycbcr_interpretation[card_index] = interpretation;
1441 }
1442
1443 void Mixer::start_mode_scanning(unsigned card_index)
1444 {
1445         assert(card_index < num_cards);
1446         if (is_mode_scanning[card_index]) {
1447                 return;
1448         }
1449         is_mode_scanning[card_index] = true;
1450         mode_scanlist[card_index].clear();
1451         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1452                 mode_scanlist[card_index].push_back(mode.first);
1453         }
1454         assert(!mode_scanlist[card_index].empty());
1455         mode_scanlist_index[card_index] = 0;
1456         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1457         last_mode_scan_change[card_index] = steady_clock::now();
1458 }
1459
1460 map<uint32_t, VideoMode> Mixer::get_available_output_video_modes() const
1461 {
1462         assert(desired_output_card_index != -1);
1463         unique_lock<mutex> lock(card_mutex);
1464         return cards[desired_output_card_index].output->get_available_video_modes();
1465 }
1466
1467 Mixer::OutputChannel::~OutputChannel()
1468 {
1469         if (has_current_frame) {
1470                 parent->release_display_frame(&current_frame);
1471         }
1472         if (has_ready_frame) {
1473                 parent->release_display_frame(&ready_frame);
1474         }
1475 }
1476
1477 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1478 {
1479         // Store this frame for display. Remove the ready frame if any
1480         // (it was seemingly never used).
1481         {
1482                 unique_lock<mutex> lock(frame_mutex);
1483                 if (has_ready_frame) {
1484                         parent->release_display_frame(&ready_frame);
1485                 }
1486                 ready_frame = frame;
1487                 has_ready_frame = true;
1488
1489                 // Call the callbacks under the mutex (they should be short),
1490                 // so that we don't race against a callback removal.
1491                 for (const auto &key_and_callback : new_frame_ready_callbacks) {
1492                         key_and_callback.second();
1493                 }
1494         }
1495
1496         // Reduce the number of callbacks by filtering duplicates. The reason
1497         // why we bother doing this is that Qt seemingly can get into a state
1498         // where its builds up an essentially unbounded queue of signals,
1499         // consuming more and more memory, and there's no good way of collapsing
1500         // user-defined signals or limiting the length of the queue.
1501         if (transition_names_updated_callback) {
1502                 vector<string> transition_names = global_mixer->get_transition_names();
1503                 bool changed = false;
1504                 if (transition_names.size() != last_transition_names.size()) {
1505                         changed = true;
1506                 } else {
1507                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1508                                 if (transition_names[i] != last_transition_names[i]) {
1509                                         changed = true;
1510                                         break;
1511                                 }
1512                         }
1513                 }
1514                 if (changed) {
1515                         transition_names_updated_callback(transition_names);
1516                         last_transition_names = transition_names;
1517                 }
1518         }
1519         if (name_updated_callback) {
1520                 string name = global_mixer->get_channel_name(channel);
1521                 if (name != last_name) {
1522                         name_updated_callback(name);
1523                         last_name = name;
1524                 }
1525         }
1526         if (color_updated_callback) {
1527                 string color = global_mixer->get_channel_color(channel);
1528                 if (color != last_color) {
1529                         color_updated_callback(color);
1530                         last_color = color;
1531                 }
1532         }
1533 }
1534
1535 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1536 {
1537         unique_lock<mutex> lock(frame_mutex);
1538         if (!has_current_frame && !has_ready_frame) {
1539                 return false;
1540         }
1541
1542         if (has_current_frame && has_ready_frame) {
1543                 // We have a new ready frame. Toss the current one.
1544                 parent->release_display_frame(&current_frame);
1545                 has_current_frame = false;
1546         }
1547         if (has_ready_frame) {
1548                 assert(!has_current_frame);
1549                 current_frame = ready_frame;
1550                 ready_frame.ready_fence.reset();  // Drop the refcount.
1551                 ready_frame.input_frames.clear();  // Drop the refcounts.
1552                 has_current_frame = true;
1553                 has_ready_frame = false;
1554         }
1555
1556         *frame = current_frame;
1557         return true;
1558 }
1559
1560 void Mixer::OutputChannel::add_frame_ready_callback(void *key, Mixer::new_frame_ready_callback_t callback)
1561 {
1562         unique_lock<mutex> lock(frame_mutex);
1563         new_frame_ready_callbacks[key] = callback;
1564 }
1565
1566 void Mixer::OutputChannel::remove_frame_ready_callback(void *key)
1567 {
1568         unique_lock<mutex> lock(frame_mutex);
1569         new_frame_ready_callbacks.erase(key);
1570 }
1571
1572 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1573 {
1574         transition_names_updated_callback = callback;
1575 }
1576
1577 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1578 {
1579         name_updated_callback = callback;
1580 }
1581
1582 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1583 {
1584         color_updated_callback = callback;
1585 }
1586
1587 mutex RefCountedGLsync::fence_lock;