git.sesse.net Git - nageru/blob - mixer.cpp

   1 #undef Success
   2
   3 #include "mixer.h"
   4
   5 #include <assert.h>
   6 #include <endian.h>
   7 #include <epoxy/egl.h>
   8 #include <movit/effect_chain.h>
   9 #include <movit/effect_util.h>
  10 #include <movit/flat_input.h>
  11 #include <movit/image_format.h>
  12 #include <movit/init.h>
  13 #include <movit/resource_pool.h>
  14 #include <movit/util.h>
  15 #include <stdint.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <sys/resource.h>
  19 #include <sys/time.h>
  20 #include <time.h>
  21 #include <algorithm>
  22 #include <chrono>
  23 #include <cmath>
  24 #include <condition_variable>
  25 #include <cstddef>
  26 #include <memory>
  27 #include <mutex>
  28 #include <string>
  29 #include <thread>
  30 #include <utility>
  31 #include <vector>
  32
  33 #include "bmusb/bmusb.h"
  34 #include "bmusb/fake_capture.h"
  35 #include "context.h"
  36 #include "db.h"
  37 #include "decklink_capture.h"
  38 #include "defs.h"
  39 #include "disk_space_estimator.h"
  40 #include "flags.h"
  41 #include "pbo_frame_allocator.h"
  42 #include "ref_counted_gl_sync.h"
  43 #include "timebase.h"
  44 #include "video_encoder.h"
  45
  46 class QOpenGLContext;
  47
  48 using namespace movit;
  49 using namespace std;
  50 using namespace std::chrono;
  51 using namespace std::placeholders;
  52 using namespace bmusb;
  53
  54 Mixer *global_mixer = nullptr;
  55 bool uses_mlock = false;
  56
  57 namespace {
  58
  59 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  60 {
  61         if (interlaced) {
  62                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  63                         input_state->buffered_frames[card_index][frame_num] =
  64                                 input_state->buffered_frames[card_index][frame_num - 1];
  65                 }
  66                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  67         } else {
  68                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  69                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  70                 }
  71         }
  72 }
  73
  74 }  // namespace
  75
  76 void QueueLengthPolicy::update_policy(int queue_length)
  77 {
  78         if (queue_length < 0) {  // Starvation.
  79                 if (been_at_safe_point_since_last_starvation && safe_queue_length < 5) {
  80                         ++safe_queue_length;
  81                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frames\n",
  82                                 card_index, safe_queue_length);
  83                 }
  84                 frames_with_at_least_one = 0;
  85                 been_at_safe_point_since_last_starvation = false;
  86                 return;
  87         }
  88         if (queue_length > 0) {
  89                 if (queue_length >= int(safe_queue_length)) {
  90                         been_at_safe_point_since_last_starvation = true;
  91                 }
  92                 if (++frames_with_at_least_one >= 1000 && safe_queue_length > 0) {
  93                         --safe_queue_length;
  94                         fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frames\n",
  95                                 card_index, safe_queue_length);
  96                         frames_with_at_least_one = 0;
  97                 }
  98         } else {
  99                 frames_with_at_least_one = 0;
 100         }
 101 }
 102
 103 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 104         : httpd(),
 105           num_cards(num_cards),
 106           mixer_surface(create_surface(format)),
 107           h264_encoder_surface(create_surface(format)),
 108           audio_mixer(num_cards),
 109           correlation(OUTPUT_FREQUENCY)
 110 {
 111         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 112         check_error();
 113
 114         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 115         // will be halved when sampling them, and we need to compensate here.
 116         movit_texel_subpixel_precision /= 2.0;
 117
 118         resource_pool.reset(new ResourcePool);
 119         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
 120         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 121                 output_channel[i].parent = this;
 122                 output_channel[i].channel = i;
 123         }
 124
 125         ImageFormat inout_format;
 126         inout_format.color_space = COLORSPACE_sRGB;
 127         inout_format.gamma_curve = GAMMA_sRGB;
 128
 129         // Display chain; shows the live output produced by the main chain (its RGBA version).
 130         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 131         check_error();
 132         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 133         display_chain->add_input(display_input);
 134         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 135         display_chain->set_dither_bits(0);  // Don't bother.
 136         display_chain->finalize();
 137
 138         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, WIDTH, HEIGHT, &httpd, global_disk_space_estimator));
 139
 140         // Start listening for clients only once VideoEncoder has written its header, if any.
 141         httpd.start(9095);
 142
 143         // First try initializing the then PCI devices, then USB, then
 144         // fill up with fake cards until we have the desired number of cards.
 145         unsigned num_pci_devices = 0;
 146         unsigned card_index = 0;
 147
 148         {
 149                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 150                 if (decklink_iterator != nullptr) {
 151                         for ( ; card_index < num_cards; ++card_index) {
 152                                 IDeckLink *decklink;
 153                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 154                                         break;
 155                                 }
 156
 157                                 configure_card(card_index, new DeckLinkCapture(decklink, card_index), /*is_fake_capture=*/false);
 158                                 ++num_pci_devices;
 159                         }
 160                         decklink_iterator->Release();
 161                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 162                 } else {
 163                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 164                 }
 165         }
 166         unsigned num_usb_devices = BMUSBCapture::num_cards();
 167         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
 168                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 169                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 170                 configure_card(card_index, capture, /*is_fake_capture=*/false);
 171         }
 172         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 173
 174         unsigned num_fake_cards = 0;
 175         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
 176                 FakeCapture *capture = new FakeCapture(WIDTH, HEIGHT, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 177                 configure_card(card_index, capture, /*is_fake_capture=*/true);
 178         }
 179
 180         if (num_fake_cards > 0) {
 181                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 182         }
 183
 184         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 185         BMUSBCapture::start_bm_thread();
 186
 187         for (card_index = 0; card_index < num_cards; ++card_index) {
 188                 cards[card_index].queue_length_policy.reset(card_index);
 189                 cards[card_index].capture->start_bm_capture();
 190         }
 191
 192         // Set up stuff for NV12 conversion.
 193
 194         // Cb/Cr shader.
 195         string cbcr_vert_shader =
 196                 "#version 130 \n"
 197                 " \n"
 198                 "in vec2 position; \n"
 199                 "in vec2 texcoord; \n"
 200                 "out vec2 tc0; \n"
 201                 "uniform vec2 foo_chroma_offset_0; \n"
 202                 " \n"
 203                 "void main() \n"
 204                 "{ \n"
 205                 "    // The result of glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0) is: \n"
 206                 "    // \n"
 207                 "    //   2.000  0.000  0.000 -1.000 \n"
 208                 "    //   0.000  2.000  0.000 -1.000 \n"
 209                 "    //   0.000  0.000 -2.000 -1.000 \n"
 210                 "    //   0.000  0.000  0.000  1.000 \n"
 211                 "    gl_Position = vec4(2.0 * position.x - 1.0, 2.0 * position.y - 1.0, -1.0, 1.0); \n"
 212                 "    vec2 flipped_tc = texcoord; \n"
 213                 "    tc0 = flipped_tc + foo_chroma_offset_0; \n"
 214                 "} \n";
 215         string cbcr_frag_shader =
 216                 "#version 130 \n"
 217                 "in vec2 tc0; \n"
 218                 "uniform sampler2D cbcr_tex; \n"
 219                 "out vec4 FragColor; \n"
 220                 "void main() { \n"
 221                 "    FragColor = texture(cbcr_tex, tc0); \n"
 222                 "} \n";
 223         vector<string> frag_shader_outputs;
 224         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
 225
 226         float vertices[] = {
 227                 0.0f, 2.0f,
 228                 0.0f, 0.0f,
 229                 2.0f, 0.0f
 230         };
 231         cbcr_vbo = generate_vbo(2, GL_FLOAT, sizeof(vertices), vertices);
 232         cbcr_position_attribute_index = glGetAttribLocation(cbcr_program_num, "position");
 233         cbcr_texcoord_attribute_index = glGetAttribLocation(cbcr_program_num, "texcoord");
 234
 235         r128.init(2, OUTPUT_FREQUENCY);
 236         r128.integr_start();
 237
 238         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
 239         // and there's a limit to how important the peak meter is.
 240         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16, /*frel=*/1.0);
 241
 242         if (global_flags.enable_alsa_output) {
 243                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 244         }
 245 }
 246
 247 Mixer::~Mixer()
 248 {
 249         resource_pool->release_glsl_program(cbcr_program_num);
 250         glDeleteBuffers(1, &cbcr_vbo);
 251         BMUSBCapture::stop_bm_thread();
 252
 253         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 254                 {
 255                         unique_lock<mutex> lock(bmusb_mutex);
 256                         cards[card_index].should_quit = true;  // Unblock thread.
 257                         cards[card_index].new_frames_changed.notify_all();
 258                 }
 259                 cards[card_index].capture->stop_dequeue_thread();
 260         }
 261
 262         video_encoder.reset(nullptr);
 263 }
 264
 265 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, bool is_fake_capture)
 266 {
 267         printf("Configuring card %d...\n", card_index);
 268
 269         CaptureCard *card = &cards[card_index];
 270         if (card->capture != nullptr) {
 271                 card->capture->stop_dequeue_thread();
 272                 delete card->capture;
 273         }
 274         card->capture = capture;
 275         card->is_fake_capture = is_fake_capture;
 276         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 277         if (card->frame_allocator == nullptr) {
 278                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
 279         }
 280         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 281         if (card->surface == nullptr) {
 282                 card->surface = create_surface_with_same_format(mixer_surface);
 283         }
 284         while (!card->new_frames.empty()) card->new_frames.pop();
 285         card->fractional_samples = 0;
 286         card->last_timecode = -1;
 287         card->capture->configure_card();
 288
 289         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 290         audio_mixer.reset_device(device);
 291         audio_mixer.set_name(device, card->capture->get_description());
 292 }
 293
 294
 295 namespace {
 296
 297 int unwrap_timecode(uint16_t current_wrapped, int last)
 298 {
 299         uint16_t last_wrapped = last & 0xffff;
 300         if (current_wrapped > last_wrapped) {
 301                 return (last & ~0xffff) | current_wrapped;
 302         } else {
 303                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 304         }
 305 }
 306
 307 float find_peak(const float *samples, size_t num_samples)
 308 {
 309         float m = fabs(samples[0]);
 310         for (size_t i = 1; i < num_samples; ++i) {
 311                 m = max(m, fabs(samples[i]));
 312         }
 313         return m;
 314 }
 315
 316 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 317 {
 318         size_t num_samples = in.size() / 2;
 319         out_l->resize(num_samples);
 320         out_r->resize(num_samples);
 321
 322         const float *inptr = in.data();
 323         float *lptr = &(*out_l)[0];
 324         float *rptr = &(*out_r)[0];
 325         for (size_t i = 0; i < num_samples; ++i) {
 326                 *lptr++ = *inptr++;
 327                 *rptr++ = *inptr++;
 328         }
 329 }
 330
 331 }  // namespace
 332
 333 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 334                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 335                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 336 {
 337         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 338         CaptureCard *card = &cards[card_index];
 339
 340         if (is_mode_scanning[card_index]) {
 341                 if (video_format.has_signal) {
 342                         // Found a stable signal, so stop scanning.
 343                         is_mode_scanning[card_index] = false;
 344                 } else {
 345                         static constexpr double switch_time_s = 0.5;  // Should be enough time for the signal to stabilize.
 346                         steady_clock::time_point now = steady_clock::now();
 347                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 348                         if (sec_since_last_switch > switch_time_s) {
 349                                 // It isn't this mode; try the next one.
 350                                 mode_scanlist_index[card_index]++;
 351                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 352                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 353                                 last_mode_scan_change[card_index] = now;
 354                         }
 355                 }
 356         }
 357
 358         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 359         assert(frame_length > 0);
 360
 361         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;
 362         if (num_samples > OUTPUT_FREQUENCY / 10) {
 363                 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",
 364                         card_index, int(audio_frame.len), int(audio_offset),
 365                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 366                 if (video_frame.owner) {
 367                         video_frame.owner->release_frame(video_frame);
 368                 }
 369                 if (audio_frame.owner) {
 370                         audio_frame.owner->release_frame(audio_frame);
 371                 }
 372                 return;
 373         }
 374
 375         int dropped_frames = 0;
 376         if (card->last_timecode != -1) {
 377                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 378         }
 379
 380         // Number of samples per frame if we need to insert silence.
 381         // (Could be nonintegral, but resampling will save us then.)
 382         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 383
 384         if (dropped_frames > MAX_FPS * 2) {
 385                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 386                         card_index, card->last_timecode, timecode);
 387                 audio_mixer.reset_device(device);
 388                 dropped_frames = 0;
 389         } else if (dropped_frames > 0) {
 390                 // Insert silence as needed.
 391                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 392                         card_index, dropped_frames, timecode);
 393
 394                 audio_mixer.add_silence(device, silence_samples, dropped_frames, frame_length);
 395         }
 396
 397         audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length);
 398
 399         // Done with the audio, so release it.
 400         if (audio_frame.owner) {
 401                 audio_frame.owner->release_frame(audio_frame);
 402         }
 403
 404         card->last_timecode = timecode;
 405
 406         size_t expected_length = video_format.width * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom) * 2;
 407         if (video_frame.len - video_offset == 0 ||
 408             video_frame.len - video_offset != expected_length) {
 409                 if (video_frame.len != 0) {
 410                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 411                                 card_index, video_frame.len - video_offset, expected_length);
 412                 }
 413                 if (video_frame.owner) {
 414                         video_frame.owner->release_frame(video_frame);
 415                 }
 416
 417                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 418                 // so that pts can go up accordingly.
 419                 {
 420                         unique_lock<mutex> lock(bmusb_mutex);
 421                         CaptureCard::NewFrame new_frame;
 422                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 423                         new_frame.length = frame_length;
 424                         new_frame.interlaced = false;
 425                         new_frame.dropped_frames = dropped_frames;
 426                         card->new_frames.push(move(new_frame));
 427                         card->new_frames_changed.notify_all();
 428                 }
 429                 return;
 430         }
 431
 432         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 433
 434         unsigned num_fields = video_format.interlaced ? 2 : 1;
 435         steady_clock::time_point frame_upload_start;
 436         if (video_format.interlaced) {
 437                 // Send the two fields along as separate frames; the other side will need to add
 438                 // a deinterlacer to actually get this right.
 439                 assert(video_format.height % 2 == 0);
 440                 video_format.height /= 2;
 441                 assert(frame_length % 2 == 0);
 442                 frame_length /= 2;
 443                 num_fields = 2;
 444                 frame_upload_start = steady_clock::now();
 445         }
 446         userdata->last_interlaced = video_format.interlaced;
 447         userdata->last_has_signal = video_format.has_signal;
 448         userdata->last_is_connected = video_format.is_connected;
 449         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 450         userdata->last_frame_rate_den = video_format.frame_rate_den;
 451         RefCountedFrame frame(video_frame);
 452
 453         // Upload the textures.
 454         size_t cbcr_width = video_format.width / 2;
 455         size_t cbcr_offset = video_offset / 2;
 456         size_t y_offset = video_frame.size / 2 + video_offset / 2;
 457
 458         for (unsigned field = 0; field < num_fields; ++field) {
 459                 // Put the actual texture upload in a lambda that is executed in the main thread.
 460                 // It is entirely possible to do this in the same thread (and it might even be
 461                 // faster, depending on the GPU and driver), but it appears to be trickling
 462                 // driver bugs very easily.
 463                 //
 464                 // Note that this means we must hold on to the actual frame data in <userdata>
 465                 // until the upload command is run, but we hold on to <frame> much longer than that
 466                 // (in fact, all the way until we no longer use the texture in rendering).
 467                 auto upload_func = [field, video_format, y_offset, cbcr_offset, cbcr_width, userdata]() {
 468                         unsigned field_start_line = (field == 1) ? video_format.second_field_start : video_format.extra_lines_top + field * (video_format.height + 22);
 469
 470                         if (userdata->tex_y[field] == 0 ||
 471                             userdata->tex_cbcr[field] == 0 ||
 472                             video_format.width != userdata->last_width[field] ||
 473                             video_format.height != userdata->last_height[field]) {
 474                                 // We changed resolution since last use of this texture, so we need to create
 475                                 // a new object. Note that this each card has its own PBOFrameAllocator,
 476                                 // we don't need to worry about these flip-flopping between resolutions.
 477                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 478                                 check_error();
 479                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, video_format.height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 480                                 check_error();
 481                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 482                                 check_error();
 483                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, video_format.width, video_format.height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 484                                 check_error();
 485                                 userdata->last_width[field] = video_format.width;
 486                                 userdata->last_height[field] = video_format.height;
 487                         }
 488
 489                         GLuint pbo = userdata->pbo;
 490                         check_error();
 491                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
 492                         check_error();
 493
 494                         size_t field_y_start = y_offset + video_format.width * field_start_line;
 495                         size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 496
 497                         if (global_flags.flush_pbos) {
 498                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_y_start, video_format.width * video_format.height);
 499                                 check_error();
 500                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_cbcr_start, cbcr_width * video_format.height * sizeof(uint16_t));
 501                                 check_error();
 502                         }
 503
 504                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 505                         check_error();
 506                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, cbcr_width, video_format.height, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_cbcr_start));
 507                         check_error();
 508                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 509                         check_error();
 510                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, video_format.width, video_format.height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_y_start));
 511                         check_error();
 512                         glBindTexture(GL_TEXTURE_2D, 0);
 513                         check_error();
 514                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 515                         check_error();
 516                 };
 517
 518                 if (field == 1) {
 519                         // Don't upload the second field as fast as we can; wait until
 520                         // the field time has approximately passed. (Otherwise, we could
 521                         // get timing jitter against the other sources, and possibly also
 522                         // against the video display, although the latter is not as critical.)
 523                         // This requires our system clock to be reasonably close to the
 524                         // video clock, but that's not an unreasonable assumption.
 525                         steady_clock::time_point second_field_start = frame_upload_start +
 526                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
 527                         this_thread::sleep_until(second_field_start);
 528                 }
 529
 530                 {
 531                         unique_lock<mutex> lock(bmusb_mutex);
 532                         CaptureCard::NewFrame new_frame;
 533                         new_frame.frame = frame;
 534                         new_frame.length = frame_length;
 535                         new_frame.field = field;
 536                         new_frame.interlaced = video_format.interlaced;
 537                         new_frame.upload_func = upload_func;
 538                         new_frame.dropped_frames = dropped_frames;
 539                         card->new_frames.push(move(new_frame));
 540                         card->new_frames_changed.notify_all();
 541                 }
 542         }
 543 }
 544
 545 void Mixer::bm_hotplug_add(libusb_device *dev)
 546 {
 547         lock_guard<mutex> lock(hotplug_mutex);
 548         hotplugged_cards.push_back(dev);
 549 }
 550
 551 void Mixer::bm_hotplug_remove(unsigned card_index)
 552 {
 553         cards[card_index].new_frames_changed.notify_all();
 554 }
 555
 556 void Mixer::thread_func()
 557 {
 558         eglBindAPI(EGL_OPENGL_API);
 559         QOpenGLContext *context = create_context(mixer_surface);
 560         if (!make_current(context, mixer_surface)) {
 561                 printf("oops\n");
 562                 exit(1);
 563         }
 564
 565         steady_clock::time_point start, now;
 566         start = steady_clock::now();
 567
 568         int frame = 0;
 569         int stats_dropped_frames = 0;
 570
 571         while (!should_quit) {
 572                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
 573                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
 574                 int num_samples[MAX_VIDEO_CARDS] = { 0 };
 575
 576                 unsigned master_card_index = theme->map_signal(master_clock_channel);
 577                 assert(master_card_index < num_cards);
 578
 579                 get_one_frame_from_each_card(master_card_index, new_frames, has_new_frame, num_samples);
 580                 schedule_audio_resampling_tasks(new_frames[master_card_index].dropped_frames, num_samples[master_card_index], new_frames[master_card_index].length);
 581                 stats_dropped_frames += new_frames[master_card_index].dropped_frames;
 582                 send_audio_level_callback();
 583
 584                 handle_hotplugged_cards();
 585
 586                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 587                         if (card_index == master_card_index || !has_new_frame[card_index]) {
 588                                 continue;
 589                         }
 590                         if (new_frames[card_index].frame->len == 0) {
 591                                 ++new_frames[card_index].dropped_frames;
 592                         }
 593                         if (new_frames[card_index].dropped_frames > 0) {
 594                                 printf("Card %u dropped %d frames before this\n",
 595                                         card_index, int(new_frames[card_index].dropped_frames));
 596                         }
 597                 }
 598
 599                 // If the first card is reporting a corrupted or otherwise dropped frame,
 600                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 601                 if (new_frames[master_card_index].frame->len == 0) {
 602                         ++stats_dropped_frames;
 603                         pts_int += new_frames[master_card_index].length;
 604                         continue;
 605                 }
 606
 607                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 608                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
 609                                 continue;
 610
 611                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
 612                         assert(new_frame->frame != nullptr);
 613                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
 614                         check_error();
 615
 616                         // The new texture might need uploading before use.
 617                         if (new_frame->upload_func) {
 618                                 new_frame->upload_func();
 619                                 new_frame->upload_func = nullptr;
 620                         }
 621                 }
 622
 623                 int64_t frame_duration = new_frames[master_card_index].length;
 624                 render_one_frame(frame_duration);
 625                 ++frame;
 626                 pts_int += frame_duration;
 627
 628                 now = steady_clock::now();
 629                 double elapsed = duration<double>(now - start).count();
 630                 if (frame % 100 == 0) {
 631                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
 632                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
 633                                 1e3 * elapsed / frame);
 634                 //      chain->print_phase_timing();
 635
 636                         // Check our memory usage, to see if we are close to our mlockall()
 637                         // limit (if at all set).
 638                         rusage used;
 639                         if (getrusage(RUSAGE_SELF, &used) == -1) {
 640                                 perror("getrusage(RUSAGE_SELF)");
 641                                 assert(false);
 642                         }
 643
 644                         if (uses_mlock) {
 645                                 rlimit limit;
 646                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
 647                                         perror("getrlimit(RLIMIT_MEMLOCK)");
 648                                         assert(false);
 649                                 }
 650
 651                                 printf(", using %ld / %ld MB lockable memory (%.1f%%)",
 652                                         long(used.ru_maxrss / 1024),
 653                                         long(limit.rlim_cur / 1048576),
 654                                         float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
 655                         } else {
 656                                 printf(", using %ld MB memory (not locked)",
 657                                         long(used.ru_maxrss / 1024));
 658                         }
 659
 660                         printf("\n");
 661                 }
 662
 663
 664                 if (should_cut.exchange(false)) {  // Test and clear.
 665                         video_encoder->do_cut(frame);
 666                 }
 667
 668 #if 0
 669                 // Reset every 100 frames, so that local variations in frame times
 670                 // (especially for the first few frames, when the shaders are
 671                 // compiled etc.) don't make it hard to measure for the entire
 672                 // remaining duration of the program.
 673                 if (frame == 10000) {
 674                         frame = 0;
 675                         start = now;
 676                 }
 677 #endif
 678                 check_error();
 679         }
 680
 681         resource_pool->clean_context();
 682 }
 683
 684 void Mixer::get_one_frame_from_each_card(unsigned master_card_index, CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS], bool has_new_frame[MAX_VIDEO_CARDS], int num_samples[MAX_VIDEO_CARDS])
 685 {
 686 start:
 687         // The first card is the master timer, so wait for it to have a new frame.
 688         // TODO: Add a timeout.
 689         unique_lock<mutex> lock(bmusb_mutex);
 690         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(); });
 691
 692         if (cards[master_card_index].new_frames.empty()) {
 693                 // We were woken up, but not due to a new frame. Deal with it
 694                 // and then restart.
 695                 assert(cards[master_card_index].capture->get_disconnected());
 696                 handle_hotplugged_cards();
 697                 goto start;
 698         }
 699
 700         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 701                 CaptureCard *card = &cards[card_index];
 702                 if (card->new_frames.empty()) {
 703                         assert(card_index != master_card_index);
 704                         card->queue_length_policy.update_policy(-1);
 705                         continue;
 706                 }
 707                 new_frames[card_index] = move(card->new_frames.front());
 708                 has_new_frame[card_index] = true;
 709                 card->new_frames.pop();
 710                 card->new_frames_changed.notify_all();
 711
 712                 int num_samples_times_timebase = OUTPUT_FREQUENCY * new_frames[card_index].length + card->fractional_samples;
 713                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
 714                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
 715                 assert(num_samples[card_index] >= 0);
 716
 717                 if (card_index == master_card_index) {
 718                         // We don't use the queue length policy for the master card,
 719                         // but we will if it stops being the master. Thus, clear out
 720                         // the policy in case we switch in the future.
 721                         card->queue_length_policy.reset(card_index);
 722                 } else {
 723                         // If we have excess frames compared to the policy for this card,
 724                         // drop frames from the head.
 725                         card->queue_length_policy.update_policy(card->new_frames.size());
 726                         while (card->new_frames.size() > card->queue_length_policy.get_safe_queue_length()) {
 727                                 card->new_frames.pop();
 728                         }
 729                 }
 730         }
 731 }
 732
 733 void Mixer::handle_hotplugged_cards()
 734 {
 735         // Check for cards that have been disconnected since last frame.
 736         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 737                 CaptureCard *card = &cards[card_index];
 738                 if (card->capture->get_disconnected()) {
 739                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
 740                         FakeCapture *capture = new FakeCapture(WIDTH, HEIGHT, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 741                         configure_card(card_index, capture, /*is_fake_capture=*/true);
 742                         card->queue_length_policy.reset(card_index);
 743                         card->capture->start_bm_capture();
 744                 }
 745         }
 746
 747         // Check for cards that have been connected since last frame.
 748         vector<libusb_device *> hotplugged_cards_copy;
 749         {
 750                 lock_guard<mutex> lock(hotplug_mutex);
 751                 swap(hotplugged_cards, hotplugged_cards_copy);
 752         }
 753         for (libusb_device *new_dev : hotplugged_cards_copy) {
 754                 // Look for a fake capture card where we can stick this in.
 755                 int free_card_index = -1;
 756                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 757                         if (cards[card_index].is_fake_capture) {
 758                                 free_card_index = int(card_index);
 759                                 break;
 760                         }
 761                 }
 762
 763                 if (free_card_index == -1) {
 764                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
 765                         libusb_unref_device(new_dev);
 766                 } else {
 767                         // BMUSBCapture takes ownership.
 768                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
 769                         CaptureCard *card = &cards[free_card_index];
 770                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
 771                         configure_card(free_card_index, capture, /*is_fake_capture=*/false);
 772                         card->queue_length_policy.reset(free_card_index);
 773                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
 774                         capture->start_bm_capture();
 775                 }
 776         }
 777 }
 778
 779
 780 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame)
 781 {
 782         // Resample the audio as needed, including from previously dropped frames.
 783         assert(num_cards > 0);
 784         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
 785                 const bool dropped_frame = (frame_num != dropped_frames);
 786                 {
 787                         // Signal to the audio thread to process this frame.
 788                         // Note that if the frame is a dropped frame, we signal that
 789                         // we don't want to use this frame as base for adjusting
 790                         // the resampler rate. The reason for this is that the timing
 791                         // of these frames is often way too late; they typically don't
 792                         // “arrive” before we synthesize them. Thus, we could end up
 793                         // in a situation where we have inserted e.g. five audio frames
 794                         // into the queue before we then start pulling five of them
 795                         // back out. This makes ResamplingQueue overestimate the delay,
 796                         // causing undue resampler changes. (We _do_ use the last,
 797                         // non-dropped frame; perhaps we should just discard that as well,
 798                         // since dropped frames are expected to be rare, and it might be
 799                         // better to just wait until we have a slightly more normal situation).
 800                         unique_lock<mutex> lock(audio_mutex);
 801                         bool adjust_rate = !dropped_frame;
 802                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate});
 803                         audio_task_queue_changed.notify_one();
 804                 }
 805                 if (dropped_frame) {
 806                         // For dropped frames, increase the pts. Note that if the format changed
 807                         // in the meantime, we have no way of detecting that; we just have to
 808                         // assume the frame length is always the same.
 809                         pts_int += length_per_frame;
 810                 }
 811         }
 812 }
 813
 814 void Mixer::render_one_frame(int64_t duration)
 815 {
 816         // Get the main chain from the theme, and set its state immediately.
 817         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
 818         EffectChain *chain = theme_main_chain.chain;
 819         theme_main_chain.setup_chain();
 820         //theme_main_chain.chain->enable_phase_timing(true);
 821
 822         GLuint y_tex, cbcr_tex;
 823         bool got_frame = video_encoder->begin_frame(&y_tex, &cbcr_tex);
 824         assert(got_frame);
 825
 826         // Render main chain.
 827         GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 828         GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 829         GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 830         check_error();
 831         chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 832         resource_pool->release_fbo(fbo);
 833
 834         subsample_chroma(cbcr_full_tex, cbcr_tex);
 835         resource_pool->release_2d_texture(cbcr_full_tex);
 836
 837         // Set the right state for rgba_tex.
 838         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 839         glBindTexture(GL_TEXTURE_2D, rgba_tex);
 840         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 841         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 842         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 843
 844         const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
 845         RefCountedGLsync fence = video_encoder->end_frame(pts_int + av_delay, duration, theme_main_chain.input_frames);
 846
 847         // The live frame just shows the RGBA texture we just rendered.
 848         // It owns rgba_tex now.
 849         DisplayFrame live_frame;
 850         live_frame.chain = display_chain.get();
 851         live_frame.setup_chain = [this, rgba_tex]{
 852                 display_input->set_texture_num(rgba_tex);
 853         };
 854         live_frame.ready_fence = fence;
 855         live_frame.input_frames = {};
 856         live_frame.temp_textures = { rgba_tex };
 857         output_channel[OUTPUT_LIVE].output_frame(live_frame);
 858
 859         // Set up preview and any additional channels.
 860         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 861                 DisplayFrame display_frame;
 862                 Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
 863                 display_frame.chain = chain.chain;
 864                 display_frame.setup_chain = chain.setup_chain;
 865                 display_frame.ready_fence = fence;
 866                 display_frame.input_frames = chain.input_frames;
 867                 display_frame.temp_textures = {};
 868                 output_channel[i].output_frame(display_frame);
 869         }
 870 }
 871
 872 void Mixer::send_audio_level_callback()
 873 {
 874         if (audio_level_callback == nullptr) {
 875                 return;
 876         }
 877
 878         unique_lock<mutex> lock(audio_measure_mutex);
 879         double loudness_s = r128.loudness_S();
 880         double loudness_i = r128.integrated();
 881         double loudness_range_low = r128.range_min();
 882         double loudness_range_high = r128.range_max();
 883
 884         audio_level_callback(loudness_s, to_db(peak),
 885                 loudness_i, loudness_range_low, loudness_range_high,
 886                 audio_mixer.get_gain_staging_db(),
 887                 audio_mixer.get_final_makeup_gain_db(),
 888                 correlation.get_correlation());
 889 }
 890
 891 void Mixer::audio_thread_func()
 892 {
 893         while (!should_quit) {
 894                 AudioTask task;
 895
 896                 {
 897                         unique_lock<mutex> lock(audio_mutex);
 898                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
 899                         if (should_quit) {
 900                                 return;
 901                         }
 902                         task = audio_task_queue.front();
 903                         audio_task_queue.pop();
 904                 }
 905
 906                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
 907                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
 908                 process_audio_one_frame(task.pts_int, task.num_samples, rate_adjustment_policy);
 909         }
 910 }
 911
 912 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples, ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy)
 913 {
 914         vector<float> samples_out = audio_mixer.get_output(double(frame_pts_int) / TIMEBASE, num_samples, rate_adjustment_policy);
 915
 916         // Upsample 4x to find interpolated peak.
 917         peak_resampler.inp_data = samples_out.data();
 918         peak_resampler.inp_count = samples_out.size() / 2;
 919
 920         vector<float> interpolated_samples_out;
 921         interpolated_samples_out.resize(samples_out.size());
 922         {
 923                 unique_lock<mutex> lock(audio_measure_mutex);
 924
 925                 while (peak_resampler.inp_count > 0) {  // About four iterations.
 926                         peak_resampler.out_data = &interpolated_samples_out[0];
 927                         peak_resampler.out_count = interpolated_samples_out.size() / 2;
 928                         peak_resampler.process();
 929                         size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
 930                         peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
 931                         peak_resampler.out_data = nullptr;
 932                 }
 933         }
 934
 935         // Find R128 levels and L/R correlation.
 936         vector<float> left, right;
 937         deinterleave_samples(samples_out, &left, &right);
 938         float *ptrs[] = { left.data(), right.data() };
 939         {
 940                 unique_lock<mutex> lock(audio_measure_mutex);
 941                 r128.process(left.size(), ptrs);
 942                 audio_mixer.set_current_loudness(r128.loudness_M());
 943                 correlation.process_samples(samples_out);
 944         }
 945
 946         // Send the samples to the sound card.
 947         if (alsa) {
 948                 alsa->write(samples_out);
 949         }
 950
 951         // And finally add them to the output.
 952         video_encoder->add_audio(frame_pts_int, move(samples_out));
 953 }
 954
 955 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 956 {
 957         GLuint vao;
 958         glGenVertexArrays(1, &vao);
 959         check_error();
 960
 961         glBindVertexArray(vao);
 962         check_error();
 963
 964         // Extract Cb/Cr.
 965         GLuint fbo = resource_pool->create_fbo(dst_tex);
 966         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 967         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 968         check_error();
 969
 970         glUseProgram(cbcr_program_num);
 971         check_error();
 972
 973         glActiveTexture(GL_TEXTURE0);
 974         check_error();
 975         glBindTexture(GL_TEXTURE_2D, src_tex);
 976         check_error();
 977         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 978         check_error();
 979         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 980         check_error();
 981         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 982         check_error();
 983
 984         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 985         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 986
 987         glBindBuffer(GL_ARRAY_BUFFER, cbcr_vbo);
 988         check_error();
 989
 990         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
 991                 glEnableVertexAttribArray(attr_index);
 992                 check_error();
 993                 glVertexAttribPointer(attr_index, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
 994                 check_error();
 995         }
 996
 997         glDrawArrays(GL_TRIANGLES, 0, 3);
 998         check_error();
 999
1000         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
1001                 glDisableVertexAttribArray(attr_index);
1002                 check_error();
1003         }
1004
1005         glUseProgram(0);
1006         check_error();
1007         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1008         check_error();
1009
1010         resource_pool->release_fbo(fbo);
1011         glDeleteVertexArrays(1, &vao);
1012 }
1013
1014 void Mixer::release_display_frame(DisplayFrame *frame)
1015 {
1016         for (GLuint texnum : frame->temp_textures) {
1017                 resource_pool->release_2d_texture(texnum);
1018         }
1019         frame->temp_textures.clear();
1020         frame->ready_fence.reset();
1021         frame->input_frames.clear();
1022 }
1023
1024 void Mixer::start()
1025 {
1026         mixer_thread = thread(&Mixer::thread_func, this);
1027         audio_thread = thread(&Mixer::audio_thread_func, this);
1028 }
1029
1030 void Mixer::quit()
1031 {
1032         should_quit = true;
1033         audio_task_queue_changed.notify_one();
1034         mixer_thread.join();
1035         audio_thread.join();
1036 }
1037
1038 void Mixer::transition_clicked(int transition_num)
1039 {
1040         theme->transition_clicked(transition_num, pts());
1041 }
1042
1043 void Mixer::channel_clicked(int preview_num)
1044 {
1045         theme->channel_clicked(preview_num);
1046 }
1047
1048 void Mixer::reset_meters()
1049 {
1050         unique_lock<mutex> lock(audio_measure_mutex);
1051         peak_resampler.reset();
1052         peak = 0.0f;
1053         r128.reset();
1054         r128.integr_start();
1055         correlation.reset();
1056 }
1057
1058 void Mixer::start_mode_scanning(unsigned card_index)
1059 {
1060         assert(card_index < num_cards);
1061         if (is_mode_scanning[card_index]) {
1062                 return;
1063         }
1064         is_mode_scanning[card_index] = true;
1065         mode_scanlist[card_index].clear();
1066         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1067                 mode_scanlist[card_index].push_back(mode.first);
1068         }
1069         assert(!mode_scanlist[card_index].empty());
1070         mode_scanlist_index[card_index] = 0;
1071         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1072         last_mode_scan_change[card_index] = steady_clock::now();
1073 }
1074
1075 Mixer::OutputChannel::~OutputChannel()
1076 {
1077         if (has_current_frame) {
1078                 parent->release_display_frame(&current_frame);
1079         }
1080         if (has_ready_frame) {
1081                 parent->release_display_frame(&ready_frame);
1082         }
1083 }
1084
1085 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1086 {
1087         // Store this frame for display. Remove the ready frame if any
1088         // (it was seemingly never used).
1089         {
1090                 unique_lock<mutex> lock(frame_mutex);
1091                 if (has_ready_frame) {
1092                         parent->release_display_frame(&ready_frame);
1093                 }
1094                 ready_frame = frame;
1095                 has_ready_frame = true;
1096         }
1097
1098         if (new_frame_ready_callback) {
1099                 new_frame_ready_callback();
1100         }
1101
1102         // Reduce the number of callbacks by filtering duplicates. The reason
1103         // why we bother doing this is that Qt seemingly can get into a state
1104         // where its builds up an essentially unbounded queue of signals,
1105         // consuming more and more memory, and there's no good way of collapsing
1106         // user-defined signals or limiting the length of the queue.
1107         if (transition_names_updated_callback) {
1108                 vector<string> transition_names = global_mixer->get_transition_names();
1109                 bool changed = false;
1110                 if (transition_names.size() != last_transition_names.size()) {
1111                         changed = true;
1112                 } else {
1113                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1114                                 if (transition_names[i] != last_transition_names[i]) {
1115                                         changed = true;
1116                                         break;
1117                                 }
1118                         }
1119                 }
1120                 if (changed) {
1121                         transition_names_updated_callback(transition_names);
1122                         last_transition_names = transition_names;
1123                 }
1124         }
1125         if (name_updated_callback) {
1126                 string name = global_mixer->get_channel_name(channel);
1127                 if (name != last_name) {
1128                         name_updated_callback(name);
1129                         last_name = name;
1130                 }
1131         }
1132         if (color_updated_callback) {
1133                 string color = global_mixer->get_channel_color(channel);
1134                 if (color != last_color) {
1135                         color_updated_callback(color);
1136                         last_color = color;
1137                 }
1138         }
1139 }
1140
1141 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1142 {
1143         unique_lock<mutex> lock(frame_mutex);
1144         if (!has_current_frame && !has_ready_frame) {
1145                 return false;
1146         }
1147
1148         if (has_current_frame && has_ready_frame) {
1149                 // We have a new ready frame. Toss the current one.
1150                 parent->release_display_frame(&current_frame);
1151                 has_current_frame = false;
1152         }
1153         if (has_ready_frame) {
1154                 assert(!has_current_frame);
1155                 current_frame = ready_frame;
1156                 ready_frame.ready_fence.reset();  // Drop the refcount.
1157                 ready_frame.input_frames.clear();  // Drop the refcounts.
1158                 has_current_frame = true;
1159                 has_ready_frame = false;
1160         }
1161
1162         *frame = current_frame;
1163         return true;
1164 }
1165
1166 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1167 {
1168         new_frame_ready_callback = callback;
1169 }
1170
1171 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1172 {
1173         transition_names_updated_callback = callback;
1174 }
1175
1176 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1177 {
1178         name_updated_callback = callback;
1179 }
1180
1181 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1182 {
1183         color_updated_callback = callback;
1184 }
1185
1186 mutex RefCountedGLsync::fence_lock;