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 "decklink_capture.h"
  37 #include "defs.h"
  38 #include "disk_space_estimator.h"
  39 #include "flags.h"
  40 #include "pbo_frame_allocator.h"
  41 #include "ref_counted_gl_sync.h"
  42 #include "timebase.h"
  43 #include "video_encoder.h"
  44
  45 class QOpenGLContext;
  46
  47 using namespace movit;
  48 using namespace std;
  49 using namespace std::chrono;
  50 using namespace std::placeholders;
  51 using namespace bmusb;
  52
  53 Mixer *global_mixer = nullptr;
  54 bool uses_mlock = false;
  55
  56 namespace {
  57
  58 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  59 {
  60         if (interlaced) {
  61                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  62                         input_state->buffered_frames[card_index][frame_num] =
  63                                 input_state->buffered_frames[card_index][frame_num - 1];
  64                 }
  65                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  66         } else {
  67                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  68                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  69                 }
  70         }
  71 }
  72
  73 }  // namespace
  74
  75 void QueueLengthPolicy::update_policy(int queue_length)
  76 {
  77         if (queue_length < 0) {  // Starvation.
  78                 if (been_at_safe_point_since_last_starvation && safe_queue_length < 5) {
  79                         ++safe_queue_length;
  80                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frames\n",
  81                                 card_index, safe_queue_length);
  82                 }
  83                 frames_with_at_least_one = 0;
  84                 been_at_safe_point_since_last_starvation = false;
  85                 return;
  86         }
  87         if (queue_length > 0) {
  88                 if (queue_length >= int(safe_queue_length)) {
  89                         been_at_safe_point_since_last_starvation = true;
  90                 }
  91                 if (++frames_with_at_least_one >= 1000 && safe_queue_length > 0) {
  92                         --safe_queue_length;
  93                         fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frames\n",
  94                                 card_index, safe_queue_length);
  95                         frames_with_at_least_one = 0;
  96                 }
  97         } else {
  98                 frames_with_at_least_one = 0;
  99         }
 100 }
 101
 102 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 103         : httpd(),
 104           num_cards(num_cards),
 105           mixer_surface(create_surface(format)),
 106           h264_encoder_surface(create_surface(format)),
 107           audio_mixer(num_cards),
 108           correlation(OUTPUT_FREQUENCY)
 109 {
 110         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 111         check_error();
 112
 113         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 114         // will be halved when sampling them, and we need to compensate here.
 115         movit_texel_subpixel_precision /= 2.0;
 116
 117         resource_pool.reset(new ResourcePool);
 118         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
 119         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 120                 output_channel[i].parent = this;
 121                 output_channel[i].channel = i;
 122         }
 123
 124         ImageFormat inout_format;
 125         inout_format.color_space = COLORSPACE_sRGB;
 126         inout_format.gamma_curve = GAMMA_sRGB;
 127
 128         // Display chain; shows the live output produced by the main chain (its RGBA version).
 129         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 130         check_error();
 131         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 132         display_chain->add_input(display_input);
 133         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 134         display_chain->set_dither_bits(0);  // Don't bother.
 135         display_chain->finalize();
 136
 137         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, WIDTH, HEIGHT, &httpd, global_disk_space_estimator));
 138
 139         // Start listening for clients only once VideoEncoder has written its header, if any.
 140         httpd.start(9095);
 141
 142         // First try initializing the then PCI devices, then USB, then
 143         // fill up with fake cards until we have the desired number of cards.
 144         unsigned num_pci_devices = 0;
 145         unsigned card_index = 0;
 146
 147         {
 148                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 149                 if (decklink_iterator != nullptr) {
 150                         for ( ; card_index < num_cards; ++card_index) {
 151                                 IDeckLink *decklink;
 152                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 153                                         break;
 154                                 }
 155
 156                                 configure_card(card_index, new DeckLinkCapture(decklink, card_index), /*is_fake_capture=*/false);
 157                                 ++num_pci_devices;
 158                         }
 159                         decklink_iterator->Release();
 160                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 161                 } else {
 162                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 163                 }
 164         }
 165         unsigned num_usb_devices = BMUSBCapture::num_cards();
 166         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
 167                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 168                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 169                 configure_card(card_index, capture, /*is_fake_capture=*/false);
 170         }
 171         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 172
 173         unsigned num_fake_cards = 0;
 174         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
 175                 FakeCapture *capture = new FakeCapture(WIDTH, HEIGHT, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 176                 configure_card(card_index, capture, /*is_fake_capture=*/true);
 177         }
 178
 179         if (num_fake_cards > 0) {
 180                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 181         }
 182
 183         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 184         BMUSBCapture::start_bm_thread();
 185
 186         for (card_index = 0; card_index < num_cards; ++card_index) {
 187                 cards[card_index].queue_length_policy.reset(card_index);
 188                 cards[card_index].capture->start_bm_capture();
 189         }
 190
 191         // Set up stuff for NV12 conversion.
 192
 193         // Cb/Cr shader.
 194         string cbcr_vert_shader =
 195                 "#version 130 \n"
 196                 " \n"
 197                 "in vec2 position; \n"
 198                 "in vec2 texcoord; \n"
 199                 "out vec2 tc0; \n"
 200                 "uniform vec2 foo_chroma_offset_0; \n"
 201                 " \n"
 202                 "void main() \n"
 203                 "{ \n"
 204                 "    // The result of glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0) is: \n"
 205                 "    // \n"
 206                 "    //   2.000  0.000  0.000 -1.000 \n"
 207                 "    //   0.000  2.000  0.000 -1.000 \n"
 208                 "    //   0.000  0.000 -2.000 -1.000 \n"
 209                 "    //   0.000  0.000  0.000  1.000 \n"
 210                 "    gl_Position = vec4(2.0 * position.x - 1.0, 2.0 * position.y - 1.0, -1.0, 1.0); \n"
 211                 "    vec2 flipped_tc = texcoord; \n"
 212                 "    tc0 = flipped_tc + foo_chroma_offset_0; \n"
 213                 "} \n";
 214         string cbcr_frag_shader =
 215                 "#version 130 \n"
 216                 "in vec2 tc0; \n"
 217                 "uniform sampler2D cbcr_tex; \n"
 218                 "out vec4 FragColor; \n"
 219                 "void main() { \n"
 220                 "    FragColor = texture(cbcr_tex, tc0); \n"
 221                 "} \n";
 222         vector<string> frag_shader_outputs;
 223         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
 224
 225         float vertices[] = {
 226                 0.0f, 2.0f,
 227                 0.0f, 0.0f,
 228                 2.0f, 0.0f
 229         };
 230         cbcr_vbo = generate_vbo(2, GL_FLOAT, sizeof(vertices), vertices);
 231         cbcr_position_attribute_index = glGetAttribLocation(cbcr_program_num, "position");
 232         cbcr_texcoord_attribute_index = glGetAttribLocation(cbcr_program_num, "texcoord");
 233
 234         r128.init(2, OUTPUT_FREQUENCY);
 235         r128.integr_start();
 236
 237         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
 238         // and there's a limit to how important the peak meter is.
 239         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16, /*frel=*/1.0);
 240
 241         if (global_flags.enable_alsa_output) {
 242                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 243         }
 244 }
 245
 246 Mixer::~Mixer()
 247 {
 248         resource_pool->release_glsl_program(cbcr_program_num);
 249         glDeleteBuffers(1, &cbcr_vbo);
 250         BMUSBCapture::stop_bm_thread();
 251
 252         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 253                 {
 254                         unique_lock<mutex> lock(bmusb_mutex);
 255                         cards[card_index].should_quit = true;  // Unblock thread.
 256                         cards[card_index].new_frames_changed.notify_all();
 257                 }
 258                 cards[card_index].capture->stop_dequeue_thread();
 259         }
 260
 261         video_encoder.reset(nullptr);
 262 }
 263
 264 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, bool is_fake_capture)
 265 {
 266         printf("Configuring card %d...\n", card_index);
 267
 268         CaptureCard *card = &cards[card_index];
 269         if (card->capture != nullptr) {
 270                 card->capture->stop_dequeue_thread();
 271                 delete card->capture;
 272         }
 273         card->capture = capture;
 274         card->is_fake_capture = is_fake_capture;
 275         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 276         if (card->frame_allocator == nullptr) {
 277                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
 278         }
 279         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 280         if (card->surface == nullptr) {
 281                 card->surface = create_surface_with_same_format(mixer_surface);
 282         }
 283         audio_mixer.reset_card(card_index);
 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
 290
 291 namespace {
 292
 293 int unwrap_timecode(uint16_t current_wrapped, int last)
 294 {
 295         uint16_t last_wrapped = last & 0xffff;
 296         if (current_wrapped > last_wrapped) {
 297                 return (last & ~0xffff) | current_wrapped;
 298         } else {
 299                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 300         }
 301 }
 302
 303 float find_peak(const float *samples, size_t num_samples)
 304 {
 305         float m = fabs(samples[0]);
 306         for (size_t i = 1; i < num_samples; ++i) {
 307                 m = max(m, fabs(samples[i]));
 308         }
 309         return m;
 310 }
 311
 312 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 313 {
 314         size_t num_samples = in.size() / 2;
 315         out_l->resize(num_samples);
 316         out_r->resize(num_samples);
 317
 318         const float *inptr = in.data();
 319         float *lptr = &(*out_l)[0];
 320         float *rptr = &(*out_r)[0];
 321         for (size_t i = 0; i < num_samples; ++i) {
 322                 *lptr++ = *inptr++;
 323                 *rptr++ = *inptr++;
 324         }
 325 }
 326
 327 }  // namespace
 328
 329 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 330                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 331                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 332 {
 333         CaptureCard *card = &cards[card_index];
 334
 335         if (is_mode_scanning[card_index]) {
 336                 if (video_format.has_signal) {
 337                         // Found a stable signal, so stop scanning.
 338                         is_mode_scanning[card_index] = false;
 339                 } else {
 340                         static constexpr double switch_time_s = 0.5;  // Should be enough time for the signal to stabilize.
 341                         steady_clock::time_point now = steady_clock::now();
 342                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 343                         if (sec_since_last_switch > switch_time_s) {
 344                                 // It isn't this mode; try the next one.
 345                                 mode_scanlist_index[card_index]++;
 346                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 347                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 348                                 last_mode_scan_change[card_index] = now;
 349                         }
 350                 }
 351         }
 352
 353         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 354         assert(frame_length > 0);
 355
 356         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;
 357         if (num_samples > OUTPUT_FREQUENCY / 10) {
 358                 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",
 359                         card_index, int(audio_frame.len), int(audio_offset),
 360                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 361                 if (video_frame.owner) {
 362                         video_frame.owner->release_frame(video_frame);
 363                 }
 364                 if (audio_frame.owner) {
 365                         audio_frame.owner->release_frame(audio_frame);
 366                 }
 367                 return;
 368         }
 369
 370         int dropped_frames = 0;
 371         if (card->last_timecode != -1) {
 372                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 373         }
 374
 375         // Number of samples per frame if we need to insert silence.
 376         // (Could be nonintegral, but resampling will save us then.)
 377         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 378
 379         if (dropped_frames > MAX_FPS * 2) {
 380                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 381                         card_index, card->last_timecode, timecode);
 382                 audio_mixer.reset_card(card_index);
 383                 dropped_frames = 0;
 384         } else if (dropped_frames > 0) {
 385                 // Insert silence as needed.
 386                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 387                         card_index, dropped_frames, timecode);
 388
 389                 audio_mixer.add_silence(card_index, silence_samples, dropped_frames, frame_length);
 390         }
 391
 392         audio_mixer.add_audio(card_index, audio_frame.data + audio_offset, num_samples, audio_format, frame_length);
 393
 394         // Done with the audio, so release it.
 395         if (audio_frame.owner) {
 396                 audio_frame.owner->release_frame(audio_frame);
 397         }
 398
 399         card->last_timecode = timecode;
 400
 401         size_t expected_length = video_format.width * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom) * 2;
 402         if (video_frame.len - video_offset == 0 ||
 403             video_frame.len - video_offset != expected_length) {
 404                 if (video_frame.len != 0) {
 405                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 406                                 card_index, video_frame.len - video_offset, expected_length);
 407                 }
 408                 if (video_frame.owner) {
 409                         video_frame.owner->release_frame(video_frame);
 410                 }
 411
 412                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 413                 // so that pts can go up accordingly.
 414                 {
 415                         unique_lock<mutex> lock(bmusb_mutex);
 416                         CaptureCard::NewFrame new_frame;
 417                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 418                         new_frame.length = frame_length;
 419                         new_frame.interlaced = false;
 420                         new_frame.dropped_frames = dropped_frames;
 421                         card->new_frames.push(move(new_frame));
 422                         card->new_frames_changed.notify_all();
 423                 }
 424                 return;
 425         }
 426
 427         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 428
 429         unsigned num_fields = video_format.interlaced ? 2 : 1;
 430         steady_clock::time_point frame_upload_start;
 431         if (video_format.interlaced) {
 432                 // Send the two fields along as separate frames; the other side will need to add
 433                 // a deinterlacer to actually get this right.
 434                 assert(video_format.height % 2 == 0);
 435                 video_format.height /= 2;
 436                 assert(frame_length % 2 == 0);
 437                 frame_length /= 2;
 438                 num_fields = 2;
 439                 frame_upload_start = steady_clock::now();
 440         }
 441         userdata->last_interlaced = video_format.interlaced;
 442         userdata->last_has_signal = video_format.has_signal;
 443         userdata->last_is_connected = video_format.is_connected;
 444         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 445         userdata->last_frame_rate_den = video_format.frame_rate_den;
 446         RefCountedFrame frame(video_frame);
 447
 448         // Upload the textures.
 449         size_t cbcr_width = video_format.width / 2;
 450         size_t cbcr_offset = video_offset / 2;
 451         size_t y_offset = video_frame.size / 2 + video_offset / 2;
 452
 453         for (unsigned field = 0; field < num_fields; ++field) {
 454                 // Put the actual texture upload in a lambda that is executed in the main thread.
 455                 // It is entirely possible to do this in the same thread (and it might even be
 456                 // faster, depending on the GPU and driver), but it appears to be trickling
 457                 // driver bugs very easily.
 458                 //
 459                 // Note that this means we must hold on to the actual frame data in <userdata>
 460                 // until the upload command is run, but we hold on to <frame> much longer than that
 461                 // (in fact, all the way until we no longer use the texture in rendering).
 462                 auto upload_func = [field, video_format, y_offset, cbcr_offset, cbcr_width, userdata]() {
 463                         unsigned field_start_line = (field == 1) ? video_format.second_field_start : video_format.extra_lines_top + field * (video_format.height + 22);
 464
 465                         if (userdata->tex_y[field] == 0 ||
 466                             userdata->tex_cbcr[field] == 0 ||
 467                             video_format.width != userdata->last_width[field] ||
 468                             video_format.height != userdata->last_height[field]) {
 469                                 // We changed resolution since last use of this texture, so we need to create
 470                                 // a new object. Note that this each card has its own PBOFrameAllocator,
 471                                 // we don't need to worry about these flip-flopping between resolutions.
 472                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 473                                 check_error();
 474                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, video_format.height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 475                                 check_error();
 476                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 477                                 check_error();
 478                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, video_format.width, video_format.height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 479                                 check_error();
 480                                 userdata->last_width[field] = video_format.width;
 481                                 userdata->last_height[field] = video_format.height;
 482                         }
 483
 484                         GLuint pbo = userdata->pbo;
 485                         check_error();
 486                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
 487                         check_error();
 488
 489                         size_t field_y_start = y_offset + video_format.width * field_start_line;
 490                         size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 491
 492                         if (global_flags.flush_pbos) {
 493                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_y_start, video_format.width * video_format.height);
 494                                 check_error();
 495                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_cbcr_start, cbcr_width * video_format.height * sizeof(uint16_t));
 496                                 check_error();
 497                         }
 498
 499                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 500                         check_error();
 501                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, cbcr_width, video_format.height, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_cbcr_start));
 502                         check_error();
 503                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 504                         check_error();
 505                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, video_format.width, video_format.height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_y_start));
 506                         check_error();
 507                         glBindTexture(GL_TEXTURE_2D, 0);
 508                         check_error();
 509                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 510                         check_error();
 511                 };
 512
 513                 if (field == 1) {
 514                         // Don't upload the second field as fast as we can; wait until
 515                         // the field time has approximately passed. (Otherwise, we could
 516                         // get timing jitter against the other sources, and possibly also
 517                         // against the video display, although the latter is not as critical.)
 518                         // This requires our system clock to be reasonably close to the
 519                         // video clock, but that's not an unreasonable assumption.
 520                         steady_clock::time_point second_field_start = frame_upload_start +
 521                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
 522                         this_thread::sleep_until(second_field_start);
 523                 }
 524
 525                 {
 526                         unique_lock<mutex> lock(bmusb_mutex);
 527                         CaptureCard::NewFrame new_frame;
 528                         new_frame.frame = frame;
 529                         new_frame.length = frame_length;
 530                         new_frame.field = field;
 531                         new_frame.interlaced = video_format.interlaced;
 532                         new_frame.upload_func = upload_func;
 533                         new_frame.dropped_frames = dropped_frames;
 534                         card->new_frames.push(move(new_frame));
 535                         card->new_frames_changed.notify_all();
 536                 }
 537         }
 538 }
 539
 540 void Mixer::bm_hotplug_add(libusb_device *dev)
 541 {
 542         lock_guard<mutex> lock(hotplug_mutex);
 543         hotplugged_cards.push_back(dev);
 544 }
 545
 546 void Mixer::bm_hotplug_remove(unsigned card_index)
 547 {
 548         cards[card_index].new_frames_changed.notify_all();
 549 }
 550
 551 void Mixer::thread_func()
 552 {
 553         eglBindAPI(EGL_OPENGL_API);
 554         QOpenGLContext *context = create_context(mixer_surface);
 555         if (!make_current(context, mixer_surface)) {
 556                 printf("oops\n");
 557                 exit(1);
 558         }
 559
 560         steady_clock::time_point start, now;
 561         start = steady_clock::now();
 562
 563         int frame = 0;
 564         int stats_dropped_frames = 0;
 565
 566         while (!should_quit) {
 567                 CaptureCard::NewFrame new_frames[MAX_CARDS];
 568                 bool has_new_frame[MAX_CARDS] = { false };
 569                 int num_samples[MAX_CARDS] = { 0 };
 570
 571                 unsigned master_card_index = theme->map_signal(master_clock_channel);
 572                 assert(master_card_index < num_cards);
 573
 574                 get_one_frame_from_each_card(master_card_index, new_frames, has_new_frame, num_samples);
 575                 schedule_audio_resampling_tasks(new_frames[master_card_index].dropped_frames, num_samples[master_card_index], new_frames[master_card_index].length);
 576                 stats_dropped_frames += new_frames[master_card_index].dropped_frames;
 577                 send_audio_level_callback();
 578
 579                 handle_hotplugged_cards();
 580
 581                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 582                         if (card_index == master_card_index || !has_new_frame[card_index]) {
 583                                 continue;
 584                         }
 585                         if (new_frames[card_index].frame->len == 0) {
 586                                 ++new_frames[card_index].dropped_frames;
 587                         }
 588                         if (new_frames[card_index].dropped_frames > 0) {
 589                                 printf("Card %u dropped %d frames before this\n",
 590                                         card_index, int(new_frames[card_index].dropped_frames));
 591                         }
 592                 }
 593
 594                 // If the first card is reporting a corrupted or otherwise dropped frame,
 595                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 596                 if (new_frames[master_card_index].frame->len == 0) {
 597                         ++stats_dropped_frames;
 598                         pts_int += new_frames[master_card_index].length;
 599                         continue;
 600                 }
 601
 602                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 603                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
 604                                 continue;
 605
 606                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
 607                         assert(new_frame->frame != nullptr);
 608                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
 609                         check_error();
 610
 611                         // The new texture might need uploading before use.
 612                         if (new_frame->upload_func) {
 613                                 new_frame->upload_func();
 614                                 new_frame->upload_func = nullptr;
 615                         }
 616                 }
 617
 618                 int64_t frame_duration = new_frames[master_card_index].length;
 619                 render_one_frame(frame_duration);
 620                 ++frame;
 621                 pts_int += frame_duration;
 622
 623                 now = steady_clock::now();
 624                 double elapsed = duration<double>(now - start).count();
 625                 if (frame % 100 == 0) {
 626                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
 627                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
 628                                 1e3 * elapsed / frame);
 629                 //      chain->print_phase_timing();
 630
 631                         // Check our memory usage, to see if we are close to our mlockall()
 632                         // limit (if at all set).
 633                         rusage used;
 634                         if (getrusage(RUSAGE_SELF, &used) == -1) {
 635                                 perror("getrusage(RUSAGE_SELF)");
 636                                 assert(false);
 637                         }
 638
 639                         if (uses_mlock) {
 640                                 rlimit limit;
 641                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
 642                                         perror("getrlimit(RLIMIT_MEMLOCK)");
 643                                         assert(false);
 644                                 }
 645
 646                                 printf(", using %ld / %ld MB lockable memory (%.1f%%)",
 647                                         long(used.ru_maxrss / 1024),
 648                                         long(limit.rlim_cur / 1048576),
 649                                         float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
 650                         } else {
 651                                 printf(", using %ld MB memory (not locked)",
 652                                         long(used.ru_maxrss / 1024));
 653                         }
 654
 655                         printf("\n");
 656                 }
 657
 658
 659                 if (should_cut.exchange(false)) {  // Test and clear.
 660                         video_encoder->do_cut(frame);
 661                 }
 662
 663 #if 0
 664                 // Reset every 100 frames, so that local variations in frame times
 665                 // (especially for the first few frames, when the shaders are
 666                 // compiled etc.) don't make it hard to measure for the entire
 667                 // remaining duration of the program.
 668                 if (frame == 10000) {
 669                         frame = 0;
 670                         start = now;
 671                 }
 672 #endif
 673                 check_error();
 674         }
 675
 676         resource_pool->clean_context();
 677 }
 678
 679 void Mixer::get_one_frame_from_each_card(unsigned master_card_index, CaptureCard::NewFrame new_frames[MAX_CARDS], bool has_new_frame[MAX_CARDS], int num_samples[MAX_CARDS])
 680 {
 681 start:
 682         // The first card is the master timer, so wait for it to have a new frame.
 683         // TODO: Add a timeout.
 684         unique_lock<mutex> lock(bmusb_mutex);
 685         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(); });
 686
 687         if (cards[master_card_index].new_frames.empty()) {
 688                 // We were woken up, but not due to a new frame. Deal with it
 689                 // and then restart.
 690                 assert(cards[master_card_index].capture->get_disconnected());
 691                 handle_hotplugged_cards();
 692                 goto start;
 693         }
 694
 695         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 696                 CaptureCard *card = &cards[card_index];
 697                 if (card->new_frames.empty()) {
 698                         assert(card_index != master_card_index);
 699                         card->queue_length_policy.update_policy(-1);
 700                         continue;
 701                 }
 702                 new_frames[card_index] = move(card->new_frames.front());
 703                 has_new_frame[card_index] = true;
 704                 card->new_frames.pop();
 705                 card->new_frames_changed.notify_all();
 706
 707                 int num_samples_times_timebase = OUTPUT_FREQUENCY * new_frames[card_index].length + card->fractional_samples;
 708                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
 709                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
 710                 assert(num_samples[card_index] >= 0);
 711
 712                 if (card_index == master_card_index) {
 713                         // We don't use the queue length policy for the master card,
 714                         // but we will if it stops being the master. Thus, clear out
 715                         // the policy in case we switch in the future.
 716                         card->queue_length_policy.reset(card_index);
 717                 } else {
 718                         // If we have excess frames compared to the policy for this card,
 719                         // drop frames from the head.
 720                         card->queue_length_policy.update_policy(card->new_frames.size());
 721                         while (card->new_frames.size() > card->queue_length_policy.get_safe_queue_length()) {
 722                                 card->new_frames.pop();
 723                         }
 724                 }
 725         }
 726 }
 727
 728 void Mixer::handle_hotplugged_cards()
 729 {
 730         // Check for cards that have been disconnected since last frame.
 731         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 732                 CaptureCard *card = &cards[card_index];
 733                 if (card->capture->get_disconnected()) {
 734                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
 735                         FakeCapture *capture = new FakeCapture(WIDTH, HEIGHT, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 736                         configure_card(card_index, capture, /*is_fake_capture=*/true);
 737                         card->queue_length_policy.reset(card_index);
 738                         card->capture->start_bm_capture();
 739                 }
 740         }
 741
 742         // Check for cards that have been connected since last frame.
 743         vector<libusb_device *> hotplugged_cards_copy;
 744         {
 745                 lock_guard<mutex> lock(hotplug_mutex);
 746                 swap(hotplugged_cards, hotplugged_cards_copy);
 747         }
 748         for (libusb_device *new_dev : hotplugged_cards_copy) {
 749                 // Look for a fake capture card where we can stick this in.
 750                 int free_card_index = -1;
 751                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 752                         if (cards[card_index].is_fake_capture) {
 753                                 free_card_index = int(card_index);
 754                                 break;
 755                         }
 756                 }
 757
 758                 if (free_card_index == -1) {
 759                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
 760                         libusb_unref_device(new_dev);
 761                 } else {
 762                         // BMUSBCapture takes ownership.
 763                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
 764                         CaptureCard *card = &cards[free_card_index];
 765                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
 766                         configure_card(free_card_index, capture, /*is_fake_capture=*/false);
 767                         card->queue_length_policy.reset(free_card_index);
 768                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
 769                         capture->start_bm_capture();
 770                 }
 771         }
 772 }
 773
 774
 775 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame)
 776 {
 777         // Resample the audio as needed, including from previously dropped frames.
 778         assert(num_cards > 0);
 779         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
 780                 const bool dropped_frame = (frame_num != dropped_frames);
 781                 {
 782                         // Signal to the audio thread to process this frame.
 783                         // Note that if the frame is a dropped frame, we signal that
 784                         // we don't want to use this frame as base for adjusting
 785                         // the resampler rate. The reason for this is that the timing
 786                         // of these frames is often way too late; they typically don't
 787                         // “arrive” before we synthesize them. Thus, we could end up
 788                         // in a situation where we have inserted e.g. five audio frames
 789                         // into the queue before we then start pulling five of them
 790                         // back out. This makes ResamplingQueue overestimate the delay,
 791                         // causing undue resampler changes. (We _do_ use the last,
 792                         // non-dropped frame; perhaps we should just discard that as well,
 793                         // since dropped frames are expected to be rare, and it might be
 794                         // better to just wait until we have a slightly more normal situation).
 795                         unique_lock<mutex> lock(audio_mutex);
 796                         bool adjust_rate = !dropped_frame;
 797                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate});
 798                         audio_task_queue_changed.notify_one();
 799                 }
 800                 if (dropped_frame) {
 801                         // For dropped frames, increase the pts. Note that if the format changed
 802                         // in the meantime, we have no way of detecting that; we just have to
 803                         // assume the frame length is always the same.
 804                         pts_int += length_per_frame;
 805                 }
 806         }
 807 }
 808
 809 void Mixer::render_one_frame(int64_t duration)
 810 {
 811         // Get the main chain from the theme, and set its state immediately.
 812         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
 813         EffectChain *chain = theme_main_chain.chain;
 814         theme_main_chain.setup_chain();
 815         //theme_main_chain.chain->enable_phase_timing(true);
 816
 817         GLuint y_tex, cbcr_tex;
 818         bool got_frame = video_encoder->begin_frame(&y_tex, &cbcr_tex);
 819         assert(got_frame);
 820
 821         // Render main chain.
 822         GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 823         GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 824         GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 825         check_error();
 826         chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 827         resource_pool->release_fbo(fbo);
 828
 829         subsample_chroma(cbcr_full_tex, cbcr_tex);
 830         resource_pool->release_2d_texture(cbcr_full_tex);
 831
 832         // Set the right state for rgba_tex.
 833         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 834         glBindTexture(GL_TEXTURE_2D, rgba_tex);
 835         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 836         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 837         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 838
 839         const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
 840         RefCountedGLsync fence = video_encoder->end_frame(pts_int + av_delay, duration, theme_main_chain.input_frames);
 841
 842         // The live frame just shows the RGBA texture we just rendered.
 843         // It owns rgba_tex now.
 844         DisplayFrame live_frame;
 845         live_frame.chain = display_chain.get();
 846         live_frame.setup_chain = [this, rgba_tex]{
 847                 display_input->set_texture_num(rgba_tex);
 848         };
 849         live_frame.ready_fence = fence;
 850         live_frame.input_frames = {};
 851         live_frame.temp_textures = { rgba_tex };
 852         output_channel[OUTPUT_LIVE].output_frame(live_frame);
 853
 854         // Set up preview and any additional channels.
 855         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 856                 DisplayFrame display_frame;
 857                 Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
 858                 display_frame.chain = chain.chain;
 859                 display_frame.setup_chain = chain.setup_chain;
 860                 display_frame.ready_fence = fence;
 861                 display_frame.input_frames = chain.input_frames;
 862                 display_frame.temp_textures = {};
 863                 output_channel[i].output_frame(display_frame);
 864         }
 865 }
 866
 867 void Mixer::send_audio_level_callback()
 868 {
 869         if (audio_level_callback == nullptr) {
 870                 return;
 871         }
 872
 873         unique_lock<mutex> lock(audio_measure_mutex);
 874         double loudness_s = r128.loudness_S();
 875         double loudness_i = r128.integrated();
 876         double loudness_range_low = r128.range_min();
 877         double loudness_range_high = r128.range_max();
 878
 879         audio_level_callback(loudness_s, 20.0 * log10(peak),
 880                 loudness_i, loudness_range_low, loudness_range_high,
 881                 audio_mixer.get_gain_staging_db(),
 882                 audio_mixer.get_final_makeup_gain_db(),
 883                 correlation.get_correlation());
 884 }
 885
 886 void Mixer::audio_thread_func()
 887 {
 888         while (!should_quit) {
 889                 AudioTask task;
 890
 891                 {
 892                         unique_lock<mutex> lock(audio_mutex);
 893                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
 894                         if (should_quit) {
 895                                 return;
 896                         }
 897                         task = audio_task_queue.front();
 898                         audio_task_queue.pop();
 899                 }
 900
 901                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
 902                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
 903                 process_audio_one_frame(task.pts_int, task.num_samples, rate_adjustment_policy);
 904         }
 905 }
 906
 907 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples, ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy)
 908 {
 909         vector<float> samples_out = audio_mixer.get_output(double(frame_pts_int) / TIMEBASE, num_samples, rate_adjustment_policy);
 910
 911         // Upsample 4x to find interpolated peak.
 912         peak_resampler.inp_data = samples_out.data();
 913         peak_resampler.inp_count = samples_out.size() / 2;
 914
 915         vector<float> interpolated_samples_out;
 916         interpolated_samples_out.resize(samples_out.size());
 917         {
 918                 unique_lock<mutex> lock(audio_measure_mutex);
 919
 920                 while (peak_resampler.inp_count > 0) {  // About four iterations.
 921                         peak_resampler.out_data = &interpolated_samples_out[0];
 922                         peak_resampler.out_count = interpolated_samples_out.size() / 2;
 923                         peak_resampler.process();
 924                         size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
 925                         peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
 926                         peak_resampler.out_data = nullptr;
 927                 }
 928         }
 929
 930         // Find R128 levels and L/R correlation.
 931         vector<float> left, right;
 932         deinterleave_samples(samples_out, &left, &right);
 933         float *ptrs[] = { left.data(), right.data() };
 934         {
 935                 unique_lock<mutex> lock(audio_measure_mutex);
 936                 r128.process(left.size(), ptrs);
 937                 audio_mixer.set_current_loudness(r128.loudness_M());
 938                 correlation.process_samples(samples_out);
 939         }
 940
 941         // Send the samples to the sound card.
 942         if (alsa) {
 943                 alsa->write(samples_out);
 944         }
 945
 946         // And finally add them to the output.
 947         video_encoder->add_audio(frame_pts_int, move(samples_out));
 948 }
 949
 950 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 951 {
 952         GLuint vao;
 953         glGenVertexArrays(1, &vao);
 954         check_error();
 955
 956         glBindVertexArray(vao);
 957         check_error();
 958
 959         // Extract Cb/Cr.
 960         GLuint fbo = resource_pool->create_fbo(dst_tex);
 961         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 962         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 963         check_error();
 964
 965         glUseProgram(cbcr_program_num);
 966         check_error();
 967
 968         glActiveTexture(GL_TEXTURE0);
 969         check_error();
 970         glBindTexture(GL_TEXTURE_2D, src_tex);
 971         check_error();
 972         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 973         check_error();
 974         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 975         check_error();
 976         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 977         check_error();
 978
 979         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 980         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 981
 982         glBindBuffer(GL_ARRAY_BUFFER, cbcr_vbo);
 983         check_error();
 984
 985         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
 986                 glEnableVertexAttribArray(attr_index);
 987                 check_error();
 988                 glVertexAttribPointer(attr_index, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
 989                 check_error();
 990         }
 991
 992         glDrawArrays(GL_TRIANGLES, 0, 3);
 993         check_error();
 994
 995         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
 996                 glDisableVertexAttribArray(attr_index);
 997                 check_error();
 998         }
 999
1000         glUseProgram(0);
1001         check_error();
1002         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1003         check_error();
1004
1005         resource_pool->release_fbo(fbo);
1006         glDeleteVertexArrays(1, &vao);
1007 }
1008
1009 void Mixer::release_display_frame(DisplayFrame *frame)
1010 {
1011         for (GLuint texnum : frame->temp_textures) {
1012                 resource_pool->release_2d_texture(texnum);
1013         }
1014         frame->temp_textures.clear();
1015         frame->ready_fence.reset();
1016         frame->input_frames.clear();
1017 }
1018
1019 void Mixer::start()
1020 {
1021         mixer_thread = thread(&Mixer::thread_func, this);
1022         audio_thread = thread(&Mixer::audio_thread_func, this);
1023 }
1024
1025 void Mixer::quit()
1026 {
1027         should_quit = true;
1028         audio_task_queue_changed.notify_one();
1029         mixer_thread.join();
1030         audio_thread.join();
1031 }
1032
1033 void Mixer::transition_clicked(int transition_num)
1034 {
1035         theme->transition_clicked(transition_num, pts());
1036 }
1037
1038 void Mixer::channel_clicked(int preview_num)
1039 {
1040         theme->channel_clicked(preview_num);
1041 }
1042
1043 void Mixer::reset_meters()
1044 {
1045         unique_lock<mutex> lock(audio_measure_mutex);
1046         peak_resampler.reset();
1047         peak = 0.0f;
1048         r128.reset();
1049         r128.integr_start();
1050         correlation.reset();
1051 }
1052
1053 void Mixer::start_mode_scanning(unsigned card_index)
1054 {
1055         assert(card_index < num_cards);
1056         if (is_mode_scanning[card_index]) {
1057                 return;
1058         }
1059         is_mode_scanning[card_index] = true;
1060         mode_scanlist[card_index].clear();
1061         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1062                 mode_scanlist[card_index].push_back(mode.first);
1063         }
1064         assert(!mode_scanlist[card_index].empty());
1065         mode_scanlist_index[card_index] = 0;
1066         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1067         last_mode_scan_change[card_index] = steady_clock::now();
1068 }
1069
1070 Mixer::OutputChannel::~OutputChannel()
1071 {
1072         if (has_current_frame) {
1073                 parent->release_display_frame(&current_frame);
1074         }
1075         if (has_ready_frame) {
1076                 parent->release_display_frame(&ready_frame);
1077         }
1078 }
1079
1080 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1081 {
1082         // Store this frame for display. Remove the ready frame if any
1083         // (it was seemingly never used).
1084         {
1085                 unique_lock<mutex> lock(frame_mutex);
1086                 if (has_ready_frame) {
1087                         parent->release_display_frame(&ready_frame);
1088                 }
1089                 ready_frame = frame;
1090                 has_ready_frame = true;
1091         }
1092
1093         if (new_frame_ready_callback) {
1094                 new_frame_ready_callback();
1095         }
1096
1097         // Reduce the number of callbacks by filtering duplicates. The reason
1098         // why we bother doing this is that Qt seemingly can get into a state
1099         // where its builds up an essentially unbounded queue of signals,
1100         // consuming more and more memory, and there's no good way of collapsing
1101         // user-defined signals or limiting the length of the queue.
1102         if (transition_names_updated_callback) {
1103                 vector<string> transition_names = global_mixer->get_transition_names();
1104                 bool changed = false;
1105                 if (transition_names.size() != last_transition_names.size()) {
1106                         changed = true;
1107                 } else {
1108                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1109                                 if (transition_names[i] != last_transition_names[i]) {
1110                                         changed = true;
1111                                         break;
1112                                 }
1113                         }
1114                 }
1115                 if (changed) {
1116                         transition_names_updated_callback(transition_names);
1117                         last_transition_names = transition_names;
1118                 }
1119         }
1120         if (name_updated_callback) {
1121                 string name = global_mixer->get_channel_name(channel);
1122                 if (name != last_name) {
1123                         name_updated_callback(name);
1124                         last_name = name;
1125                 }
1126         }
1127         if (color_updated_callback) {
1128                 string color = global_mixer->get_channel_color(channel);
1129                 if (color != last_color) {
1130                         color_updated_callback(color);
1131                         last_color = color;
1132                 }
1133         }
1134 }
1135
1136 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1137 {
1138         unique_lock<mutex> lock(frame_mutex);
1139         if (!has_current_frame && !has_ready_frame) {
1140                 return false;
1141         }
1142
1143         if (has_current_frame && has_ready_frame) {
1144                 // We have a new ready frame. Toss the current one.
1145                 parent->release_display_frame(&current_frame);
1146                 has_current_frame = false;
1147         }
1148         if (has_ready_frame) {
1149                 assert(!has_current_frame);
1150                 current_frame = ready_frame;
1151                 ready_frame.ready_fence.reset();  // Drop the refcount.
1152                 ready_frame.input_frames.clear();  // Drop the refcounts.
1153                 has_current_frame = true;
1154                 has_ready_frame = false;
1155         }
1156
1157         *frame = current_frame;
1158         return true;
1159 }
1160
1161 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1162 {
1163         new_frame_ready_callback = callback;
1164 }
1165
1166 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1167 {
1168         transition_names_updated_callback = callback;
1169 }
1170
1171 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1172 {
1173         name_updated_callback = callback;
1174 }
1175
1176 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1177 {
1178         color_updated_callback = callback;
1179 }
1180
1181 mutex RefCountedGLsync::fence_lock;