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

   1 #undef Success
   2
   3 #include "mixer.h"
   4
   5 #include <assert.h>
   6 #include <epoxy/egl.h>
   7 #include <movit/effect_chain.h>
   8 #include <movit/effect_util.h>
   9 #include <movit/flat_input.h>
  10 #include <movit/image_format.h>
  11 #include <movit/init.h>
  12 #include <movit/resource_pool.h>
  13 #include <pthread.h>
  14 #include <stdint.h>
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <sys/resource.h>
  18 #include <algorithm>
  19 #include <chrono>
  20 #include <condition_variable>
  21 #include <cstddef>
  22 #include <cstdint>
  23 #include <memory>
  24 #include <mutex>
  25 #include <ratio>
  26 #include <string>
  27 #include <thread>
  28 #include <utility>
  29 #include <vector>
  30
  31 #include "DeckLinkAPI.h"
  32 #include "LinuxCOM.h"
  33 #include "alsa_output.h"
  34 #include "bmusb/bmusb.h"
  35 #include "bmusb/fake_capture.h"
  36 #include "chroma_subsampler.h"
  37 #include "context.h"
  38 #include "decklink_capture.h"
  39 #include "decklink_output.h"
  40 #include "defs.h"
  41 #include "disk_space_estimator.h"
  42 #include "flags.h"
  43 #include "input_mapping.h"
  44 #include "pbo_frame_allocator.h"
  45 #include "ref_counted_gl_sync.h"
  46 #include "resampling_queue.h"
  47 #include "timebase.h"
  48 #include "timecode_renderer.h"
  49 #include "v210_converter.h"
  50 #include "video_encoder.h"
  51
  52 class IDeckLink;
  53 class QOpenGLContext;
  54
  55 using namespace movit;
  56 using namespace std;
  57 using namespace std::chrono;
  58 using namespace std::placeholders;
  59 using namespace bmusb;
  60
  61 Mixer *global_mixer = nullptr;
  62 bool uses_mlock = false;
  63
  64 namespace {
  65
  66 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  67 {
  68         if (interlaced) {
  69                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  70                         input_state->buffered_frames[card_index][frame_num] =
  71                                 input_state->buffered_frames[card_index][frame_num - 1];
  72                 }
  73                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  74         } else {
  75                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  76                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  77                 }
  78         }
  79 }
  80
  81 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned v210_width)
  82 {
  83         bool first;
  84         if (global_flags.ten_bit_input) {
  85                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
  86         } else {
  87                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
  88         }
  89
  90         if (first ||
  91             width != userdata->last_width[field] ||
  92             height != userdata->last_height[field]) {
  93                 // We changed resolution since last use of this texture, so we need to create
  94                 // a new object. Note that this each card has its own PBOFrameAllocator,
  95                 // we don't need to worry about these flip-flopping between resolutions.
  96                 if (global_flags.ten_bit_input) {
  97                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
  98                         check_error();
  99                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 100                         check_error();
 101                 } else {
 102                         size_t cbcr_width = width / 2;
 103
 104                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 105                         check_error();
 106                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 107                         check_error();
 108                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 109                         check_error();
 110                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 111                         check_error();
 112                 }
 113                 userdata->last_width[field] = width;
 114                 userdata->last_height[field] = height;
 115         }
 116         if (global_flags.ten_bit_input &&
 117             (first || v210_width != userdata->last_v210_width[field])) {
 118                 // Same as above; we need to recreate the texture.
 119                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
 120                 check_error();
 121                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 122                 check_error();
 123                 userdata->last_v210_width[field] = v210_width;
 124         }
 125 }
 126
 127 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
 128 {
 129         if (interlaced_stride) {
 130                 stride *= 2;
 131         }
 132         if (global_flags.flush_pbos) {
 133                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
 134                 check_error();
 135         }
 136
 137         glBindTexture(GL_TEXTURE_2D, tex);
 138         check_error();
 139         if (interlaced_stride) {
 140                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
 141                 check_error();
 142         } else {
 143                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 144                 check_error();
 145         }
 146
 147         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
 148         check_error();
 149         glBindTexture(GL_TEXTURE_2D, 0);
 150         check_error();
 151         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 152         check_error();
 153 }
 154
 155 }  // namespace
 156
 157 void QueueLengthPolicy::update_policy(unsigned queue_length)
 158 {
 159         if (queue_length == 0) {  // Starvation.
 160                 if (been_at_safe_point_since_last_starvation && safe_queue_length < unsigned(global_flags.max_input_queue_frames)) {
 161                         ++safe_queue_length;
 162                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frame(s)\n",
 163                                 card_index, safe_queue_length);
 164                 }
 165                 frames_with_at_least_one = 0;
 166                 been_at_safe_point_since_last_starvation = false;
 167                 return;
 168         }
 169         if (queue_length >= 1) {
 170                 if (queue_length >= safe_queue_length) {
 171                         been_at_safe_point_since_last_starvation = true;
 172                 }
 173                 if (++frames_with_at_least_one >= 1000 && safe_queue_length > 1) {
 174                         --safe_queue_length;
 175                         fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frame(s)\n",
 176                                 card_index, safe_queue_length);
 177                         frames_with_at_least_one = 0;
 178                 }
 179         } else {
 180                 frames_with_at_least_one = 0;
 181         }
 182 }
 183
 184 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 185         : httpd(),
 186           num_cards(num_cards),
 187           mixer_surface(create_surface(format)),
 188           h264_encoder_surface(create_surface(format)),
 189           decklink_output_surface(create_surface(format)),
 190           audio_mixer(num_cards)
 191 {
 192         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 193         check_error();
 194
 195         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 196         // will be halved when sampling them, and we need to compensate here.
 197         movit_texel_subpixel_precision /= 2.0;
 198
 199         resource_pool.reset(new ResourcePool);
 200         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
 201         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 202                 output_channel[i].parent = this;
 203                 output_channel[i].channel = i;
 204         }
 205
 206         ImageFormat inout_format;
 207         inout_format.color_space = COLORSPACE_sRGB;
 208         inout_format.gamma_curve = GAMMA_sRGB;
 209
 210         // Display chain; shows the live output produced by the main chain (its RGBA version).
 211         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
 212         check_error();
 213         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, global_flags.width, global_flags.height);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 214         display_chain->add_input(display_input);
 215         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 216         display_chain->set_dither_bits(0);  // Don't bother.
 217         display_chain->finalize();
 218
 219         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, global_flags.width, global_flags.height, &httpd, global_disk_space_estimator));
 220
 221         // Start listening for clients only once VideoEncoder has written its header, if any.
 222         httpd.start(9095);
 223
 224         // First try initializing the then PCI devices, then USB, then
 225         // fill up with fake cards until we have the desired number of cards.
 226         unsigned num_pci_devices = 0;
 227         unsigned card_index = 0;
 228
 229         {
 230                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 231                 if (decklink_iterator != nullptr) {
 232                         for ( ; card_index < num_cards; ++card_index) {
 233                                 IDeckLink *decklink;
 234                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 235                                         break;
 236                                 }
 237
 238                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
 239                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
 240                                 output->set_device(decklink);
 241                                 configure_card(card_index, capture, /*is_fake_capture=*/false, output);
 242                                 ++num_pci_devices;
 243                         }
 244                         decklink_iterator->Release();
 245                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 246                 } else {
 247                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 248                 }
 249         }
 250
 251         unsigned num_usb_devices = BMUSBCapture::num_cards();
 252         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
 253                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 254                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 255                 configure_card(card_index, capture, /*is_fake_capture=*/false, /*output=*/nullptr);
 256         }
 257         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 258
 259         unsigned num_fake_cards = 0;
 260         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
 261                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 262                 configure_card(card_index, capture, /*is_fake_capture=*/true, /*output=*/nullptr);
 263         }
 264
 265         if (num_fake_cards > 0) {
 266                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 267         }
 268
 269         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 270         BMUSBCapture::start_bm_thread();
 271
 272         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 273                 cards[card_index].queue_length_policy.reset(card_index);
 274         }
 275
 276         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
 277
 278         if (global_flags.ten_bit_input) {
 279                 if (!v210Converter::has_hardware_support()) {
 280                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
 281                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 282                         exit(1);
 283                 }
 284                 v210_converter.reset(new v210Converter());
 285
 286                 // These are all the widths listed in the Blackmagic SDK documentation
 287                 // (section 2.7.3, “Display Modes”).
 288                 v210_converter->precompile_shader(720);
 289                 v210_converter->precompile_shader(1280);
 290                 v210_converter->precompile_shader(1920);
 291                 v210_converter->precompile_shader(2048);
 292                 v210_converter->precompile_shader(3840);
 293                 v210_converter->precompile_shader(4096);
 294         }
 295
 296         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
 297         display_timecode_in_stream = global_flags.display_timecode_in_stream;
 298         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
 299
 300         if (global_flags.enable_alsa_output) {
 301                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 302         }
 303         if (global_flags.output_card != -1) {
 304                 desired_output_card_index = global_flags.output_card;
 305                 set_output_card_internal(global_flags.output_card);
 306         }
 307 }
 308
 309 Mixer::~Mixer()
 310 {
 311         BMUSBCapture::stop_bm_thread();
 312
 313         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 314                 {
 315                         unique_lock<mutex> lock(card_mutex);
 316                         cards[card_index].should_quit = true;  // Unblock thread.
 317                         cards[card_index].new_frames_changed.notify_all();
 318                 }
 319                 cards[card_index].capture->stop_dequeue_thread();
 320                 if (cards[card_index].output) {
 321                         cards[card_index].output->end_output();
 322                         cards[card_index].output.reset();
 323                 }
 324         }
 325
 326         video_encoder.reset(nullptr);
 327 }
 328
 329 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, bool is_fake_capture, DeckLinkOutput *output)
 330 {
 331         printf("Configuring card %d...\n", card_index);
 332
 333         CaptureCard *card = &cards[card_index];
 334         if (card->capture != nullptr) {
 335                 card->capture->stop_dequeue_thread();
 336         }
 337         card->capture.reset(capture);
 338         card->is_fake_capture = is_fake_capture;
 339         if (card->output.get() != output) {
 340                 card->output.reset(output);
 341         }
 342         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 343         if (card->frame_allocator == nullptr) {
 344                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, global_flags.width, global_flags.height));  // 8 MB.
 345         }
 346         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 347         if (card->surface == nullptr) {
 348                 card->surface = create_surface_with_same_format(mixer_surface);
 349         }
 350         while (!card->new_frames.empty()) card->new_frames.pop_front();
 351         card->last_timecode = -1;
 352         card->capture->set_pixel_format(global_flags.ten_bit_input ? PixelFormat_10BitYCbCr : PixelFormat_8BitYCbCr);
 353         card->capture->configure_card();
 354
 355         // NOTE: start_bm_capture() happens in thread_func().
 356
 357         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 358         audio_mixer.reset_resampler(device);
 359         audio_mixer.set_display_name(device, card->capture->get_description());
 360         audio_mixer.trigger_state_changed_callback();
 361 }
 362
 363 void Mixer::set_output_card_internal(int card_index)
 364 {
 365         // We don't really need to take card_mutex, since we're in the mixer
 366         // thread and don't mess with any queues (which is the only thing that happens
 367         // from other threads), but it's probably the safest in the long run.
 368         unique_lock<mutex> lock(card_mutex);
 369         if (output_card_index != -1) {
 370                 // Switch the old card from output to input.
 371                 CaptureCard *old_card = &cards[output_card_index];
 372                 old_card->output->end_output();
 373
 374                 // Stop the fake card that we put into place.
 375                 // This needs to _not_ happen under the mutex, to avoid deadlock
 376                 // (delivering the last frame needs to take the mutex).
 377                 bmusb::CaptureInterface *fake_capture = old_card->capture.get();
 378                 lock.unlock();
 379                 fake_capture->stop_dequeue_thread();
 380                 lock.lock();
 381                 old_card->capture = move(old_card->parked_capture);
 382                 old_card->is_fake_capture = false;
 383                 old_card->capture->start_bm_capture();
 384         }
 385         if (card_index != -1) {
 386                 CaptureCard *card = &cards[card_index];
 387                 bmusb::CaptureInterface *capture = card->capture.get();
 388                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
 389                 // several seconds to complete (blocking on DisableVideoInput);
 390                 // see if we can maybe do it asynchronously.
 391                 lock.unlock();
 392                 capture->stop_dequeue_thread();
 393                 lock.lock();
 394                 card->parked_capture = move(card->capture);
 395                 bmusb::CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 396                 configure_card(card_index, fake_capture, /*is_fake_capture=*/true, card->output.release());
 397                 card->queue_length_policy.reset(card_index);
 398                 card->capture->start_bm_capture();
 399                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
 400                 card->output->start_output(desired_output_video_mode, pts_int);
 401         }
 402         output_card_index = card_index;
 403 }
 404
 405 namespace {
 406
 407 int unwrap_timecode(uint16_t current_wrapped, int last)
 408 {
 409         uint16_t last_wrapped = last & 0xffff;
 410         if (current_wrapped > last_wrapped) {
 411                 return (last & ~0xffff) | current_wrapped;
 412         } else {
 413                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 414         }
 415 }
 416
 417 }  // namespace
 418
 419 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 420                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 421                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 422 {
 423         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 424         CaptureCard *card = &cards[card_index];
 425
 426         if (is_mode_scanning[card_index]) {
 427                 if (video_format.has_signal) {
 428                         // Found a stable signal, so stop scanning.
 429                         is_mode_scanning[card_index] = false;
 430                 } else {
 431                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
 432                         steady_clock::time_point now = steady_clock::now();
 433                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 434                         if (sec_since_last_switch > switch_time_s) {
 435                                 // It isn't this mode; try the next one.
 436                                 mode_scanlist_index[card_index]++;
 437                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 438                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 439                                 last_mode_scan_change[card_index] = now;
 440                         }
 441                 }
 442         }
 443
 444         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 445         assert(frame_length > 0);
 446
 447         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;
 448         if (num_samples > OUTPUT_FREQUENCY / 10) {
 449                 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",
 450                         card_index, int(audio_frame.len), int(audio_offset),
 451                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 452                 if (video_frame.owner) {
 453                         video_frame.owner->release_frame(video_frame);
 454                 }
 455                 if (audio_frame.owner) {
 456                         audio_frame.owner->release_frame(audio_frame);
 457                 }
 458                 return;
 459         }
 460
 461         int dropped_frames = 0;
 462         if (card->last_timecode != -1) {
 463                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 464         }
 465
 466         // Number of samples per frame if we need to insert silence.
 467         // (Could be nonintegral, but resampling will save us then.)
 468         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 469
 470         if (dropped_frames > MAX_FPS * 2) {
 471                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 472                         card_index, card->last_timecode, timecode);
 473                 audio_mixer.reset_resampler(device);
 474                 dropped_frames = 0;
 475         } else if (dropped_frames > 0) {
 476                 // Insert silence as needed.
 477                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 478                         card_index, dropped_frames, timecode);
 479
 480                 bool success;
 481                 do {
 482                         success = audio_mixer.add_silence(device, silence_samples, dropped_frames, frame_length);
 483                 } while (!success);
 484         }
 485
 486         audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
 487
 488         // Done with the audio, so release it.
 489         if (audio_frame.owner) {
 490                 audio_frame.owner->release_frame(audio_frame);
 491         }
 492
 493         card->last_timecode = timecode;
 494
 495         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
 496         if (video_frame.len - video_offset == 0 ||
 497             video_frame.len - video_offset != expected_length) {
 498                 if (video_frame.len != 0) {
 499                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 500                                 card_index, video_frame.len - video_offset, expected_length);
 501                 }
 502                 if (video_frame.owner) {
 503                         video_frame.owner->release_frame(video_frame);
 504                 }
 505
 506                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 507                 // so that pts can go up accordingly.
 508                 {
 509                         unique_lock<mutex> lock(card_mutex);
 510                         CaptureCard::NewFrame new_frame;
 511                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 512                         new_frame.length = frame_length;
 513                         new_frame.interlaced = false;
 514                         new_frame.dropped_frames = dropped_frames;
 515                         new_frame.received_timestamp = video_frame.received_timestamp;
 516                         card->new_frames.push_back(move(new_frame));
 517                         card->new_frames_changed.notify_all();
 518                 }
 519                 return;
 520         }
 521
 522         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 523
 524         unsigned num_fields = video_format.interlaced ? 2 : 1;
 525         steady_clock::time_point frame_upload_start;
 526         bool interlaced_stride = false;
 527         if (video_format.interlaced) {
 528                 // Send the two fields along as separate frames; the other side will need to add
 529                 // a deinterlacer to actually get this right.
 530                 assert(video_format.height % 2 == 0);
 531                 video_format.height /= 2;
 532                 assert(frame_length % 2 == 0);
 533                 frame_length /= 2;
 534                 num_fields = 2;
 535                 if (video_format.second_field_start == 1) {
 536                         interlaced_stride = true;
 537                 }
 538                 frame_upload_start = steady_clock::now();
 539         }
 540         userdata->last_interlaced = video_format.interlaced;
 541         userdata->last_has_signal = video_format.has_signal;
 542         userdata->last_is_connected = video_format.is_connected;
 543         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 544         userdata->last_frame_rate_den = video_format.frame_rate_den;
 545         RefCountedFrame frame(video_frame);
 546
 547         // Upload the textures.
 548         const size_t cbcr_width = video_format.width / 2;
 549         const size_t cbcr_offset = video_offset / 2;
 550         const size_t y_offset = video_frame.size / 2 + video_offset / 2;
 551
 552         for (unsigned field = 0; field < num_fields; ++field) {
 553                 // Put the actual texture upload in a lambda that is executed in the main thread.
 554                 // It is entirely possible to do this in the same thread (and it might even be
 555                 // faster, depending on the GPU and driver), but it appears to be trickling
 556                 // driver bugs very easily.
 557                 //
 558                 // Note that this means we must hold on to the actual frame data in <userdata>
 559                 // until the upload command is run, but we hold on to <frame> much longer than that
 560                 // (in fact, all the way until we no longer use the texture in rendering).
 561                 auto upload_func = [this, field, video_format, y_offset, video_offset, cbcr_offset, cbcr_width, interlaced_stride, userdata]() {
 562                         unsigned field_start_line;
 563                         if (field == 1) {
 564                                 field_start_line = video_format.second_field_start;
 565                         } else {
 566                                 field_start_line = video_format.extra_lines_top;
 567                         }
 568
 569                         // For 8-bit input, v210_width will be nonsensical but not used.
 570                         size_t v210_width = video_format.stride / sizeof(uint32_t);
 571                         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, v210_width);
 572
 573                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
 574                         check_error();
 575
 576                         if (global_flags.ten_bit_input) {
 577                                 size_t field_start = video_offset + video_format.stride * field_start_line;
 578                                 upload_texture(userdata->tex_v210[field], v210_width, video_format.height, video_format.stride, interlaced_stride, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, field_start);
 579                                 v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
 580                         } else {
 581                                 size_t field_y_start = y_offset + video_format.width * field_start_line;
 582                                 size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 583
 584                                 // Make up our own strides, since we are interleaving.
 585                                 upload_texture(userdata->tex_y[field], video_format.width, video_format.height, video_format.width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_y_start);
 586                                 upload_texture(userdata->tex_cbcr[field], cbcr_width, video_format.height, cbcr_width * sizeof(uint16_t), interlaced_stride, GL_RG, GL_UNSIGNED_BYTE, field_cbcr_start);
 587                         }
 588
 589                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 590                         check_error();
 591                 };
 592
 593                 if (field == 1) {
 594                         // Don't upload the second field as fast as we can; wait until
 595                         // the field time has approximately passed. (Otherwise, we could
 596                         // get timing jitter against the other sources, and possibly also
 597                         // against the video display, although the latter is not as critical.)
 598                         // This requires our system clock to be reasonably close to the
 599                         // video clock, but that's not an unreasonable assumption.
 600                         steady_clock::time_point second_field_start = frame_upload_start +
 601                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
 602                         this_thread::sleep_until(second_field_start);
 603                 }
 604
 605                 {
 606                         unique_lock<mutex> lock(card_mutex);
 607                         CaptureCard::NewFrame new_frame;
 608                         new_frame.frame = frame;
 609                         new_frame.length = frame_length;
 610                         new_frame.field = field;
 611                         new_frame.interlaced = video_format.interlaced;
 612                         new_frame.upload_func = upload_func;
 613                         new_frame.dropped_frames = dropped_frames;
 614                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
 615                         card->new_frames.push_back(move(new_frame));
 616                         card->new_frames_changed.notify_all();
 617                 }
 618         }
 619 }
 620
 621 void Mixer::bm_hotplug_add(libusb_device *dev)
 622 {
 623         lock_guard<mutex> lock(hotplug_mutex);
 624         hotplugged_cards.push_back(dev);
 625 }
 626
 627 void Mixer::bm_hotplug_remove(unsigned card_index)
 628 {
 629         cards[card_index].new_frames_changed.notify_all();
 630 }
 631
 632 void Mixer::thread_func()
 633 {
 634         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
 635
 636         eglBindAPI(EGL_OPENGL_API);
 637         QOpenGLContext *context = create_context(mixer_surface);
 638         if (!make_current(context, mixer_surface)) {
 639                 printf("oops\n");
 640                 exit(1);
 641         }
 642
 643         // Start the actual capture. (We don't want to do it before we're actually ready
 644         // to process output frames.)
 645         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 646                 if (int(card_index) != output_card_index) {
 647                         cards[card_index].capture->start_bm_capture();
 648                 }
 649         }
 650
 651         steady_clock::time_point start, now;
 652         start = steady_clock::now();
 653
 654         int stats_dropped_frames = 0;
 655
 656         while (!should_quit) {
 657                 if (desired_output_card_index != output_card_index) {
 658                         set_output_card_internal(desired_output_card_index);
 659                 }
 660                 if (output_card_index != -1 &&
 661                     desired_output_video_mode != output_video_mode) {
 662                         DeckLinkOutput *output = cards[output_card_index].output.get();
 663                         output->end_output();
 664                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
 665                         output->start_output(desired_output_video_mode, pts_int);
 666                 }
 667
 668                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
 669                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
 670
 671                 bool master_card_is_output;
 672                 unsigned master_card_index;
 673                 if (output_card_index != -1) {
 674                         master_card_is_output = true;
 675                         master_card_index = output_card_index;
 676                 } else {
 677                         master_card_is_output = false;
 678                         master_card_index = theme->map_signal(master_clock_channel);
 679                         assert(master_card_index < num_cards);
 680                 }
 681
 682                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
 683                 schedule_audio_resampling_tasks(output_frame_info.dropped_frames, output_frame_info.num_samples, output_frame_info.frame_duration, output_frame_info.is_preroll, output_frame_info.frame_timestamp);
 684                 stats_dropped_frames += output_frame_info.dropped_frames;
 685
 686                 handle_hotplugged_cards();
 687
 688                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 689                         if (card_index == master_card_index || !has_new_frame[card_index]) {
 690                                 continue;
 691                         }
 692                         if (new_frames[card_index].frame->len == 0) {
 693                                 ++new_frames[card_index].dropped_frames;
 694                         }
 695                         if (new_frames[card_index].dropped_frames > 0) {
 696                                 printf("Card %u dropped %d frames before this\n",
 697                                         card_index, int(new_frames[card_index].dropped_frames));
 698                         }
 699                 }
 700
 701                 // If the first card is reporting a corrupted or otherwise dropped frame,
 702                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 703                 if (!master_card_is_output && new_frames[master_card_index].frame->len == 0) {
 704                         ++stats_dropped_frames;
 705                         pts_int += new_frames[master_card_index].length;
 706                         continue;
 707                 }
 708
 709                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 710                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
 711                                 continue;
 712
 713                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
 714                         assert(new_frame->frame != nullptr);
 715                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
 716                         check_error();
 717
 718                         // The new texture might need uploading before use.
 719                         if (new_frame->upload_func) {
 720                                 new_frame->upload_func();
 721                                 new_frame->upload_func = nullptr;
 722                         }
 723                 }
 724
 725                 int64_t frame_duration = output_frame_info.frame_duration;
 726                 render_one_frame(frame_duration);
 727                 ++frame_num;
 728                 pts_int += frame_duration;
 729
 730                 now = steady_clock::now();
 731                 double elapsed = duration<double>(now - start).count();
 732                 if (frame_num % 100 == 0) {
 733                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
 734                                 frame_num, stats_dropped_frames, elapsed, frame_num / elapsed,
 735                                 1e3 * elapsed / frame_num);
 736                 //      chain->print_phase_timing();
 737
 738                         // Check our memory usage, to see if we are close to our mlockall()
 739                         // limit (if at all set).
 740                         rusage used;
 741                         if (getrusage(RUSAGE_SELF, &used) == -1) {
 742                                 perror("getrusage(RUSAGE_SELF)");
 743                                 assert(false);
 744                         }
 745
 746                         if (uses_mlock) {
 747                                 rlimit limit;
 748                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
 749                                         perror("getrlimit(RLIMIT_MEMLOCK)");
 750                                         assert(false);
 751                                 }
 752
 753                                 if (limit.rlim_cur == 0) {
 754                                         printf(", using %ld MB memory (locked)",
 755                                                 long(used.ru_maxrss / 1024));
 756                                 } else {
 757                                         printf(", using %ld / %ld MB lockable memory (%.1f%%)",
 758                                                 long(used.ru_maxrss / 1024),
 759                                                 long(limit.rlim_cur / 1048576),
 760                                                 float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
 761                                 }
 762                         } else {
 763                                 printf(", using %ld MB memory (not locked)",
 764                                         long(used.ru_maxrss / 1024));
 765                         }
 766
 767                         printf("\n");
 768                 }
 769
 770
 771                 if (should_cut.exchange(false)) {  // Test and clear.
 772                         video_encoder->do_cut(frame_num);
 773                 }
 774
 775 #if 0
 776                 // Reset every 100 frames, so that local variations in frame times
 777                 // (especially for the first few frames, when the shaders are
 778                 // compiled etc.) don't make it hard to measure for the entire
 779                 // remaining duration of the program.
 780                 if (frame == 10000) {
 781                         frame = 0;
 782                         start = now;
 783                 }
 784 #endif
 785                 check_error();
 786         }
 787
 788         resource_pool->clean_context();
 789 }
 790
 791 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
 792 {
 793         if (output_card_index != -1) {
 794                 // The output card (ie., cards[output_card_index].output) is the master clock,
 795                 // so no input card (ie., cards[card_index].capture) is.
 796                 return false;
 797         }
 798         return (card_index == master_card_index);
 799 }
 800
 801 void Mixer::trim_queue(CaptureCard *card, unsigned card_index)
 802 {
 803         // Count the number of frames in the queue, including any frames
 804         // we dropped. It's hard to know exactly how we should deal with
 805         // dropped (corrupted) input frames; they don't help our goal of
 806         // avoiding starvation, but they still add to the problem of latency.
 807         // Since dropped frames is going to mean a bump in the signal anyway,
 808         // we err on the side of having more stable latency instead.
 809         unsigned queue_length = 0;
 810         for (const CaptureCard::NewFrame &frame : card->new_frames) {
 811                 queue_length += frame.dropped_frames + 1;
 812         }
 813         card->queue_length_policy.update_policy(queue_length);
 814
 815         // If needed, drop frames until the queue is below the safe limit.
 816         // We prefer to drop from the head, because all else being equal,
 817         // we'd like more recent frames (less latency).
 818         unsigned dropped_frames = 0;
 819         while (queue_length > card->queue_length_policy.get_safe_queue_length()) {
 820                 assert(!card->new_frames.empty());
 821                 assert(queue_length > card->new_frames.front().dropped_frames);
 822                 queue_length -= card->new_frames.front().dropped_frames;
 823
 824                 if (queue_length <= card->queue_length_policy.get_safe_queue_length()) {
 825                         // No need to drop anything.
 826                         break;
 827                 }
 828
 829                 card->new_frames.pop_front();
 830                 card->new_frames_changed.notify_all();
 831                 --queue_length;
 832                 ++dropped_frames;
 833         }
 834
 835         if (dropped_frames > 0) {
 836                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
 837                         card_index, dropped_frames);
 838         }
 839 }
 840
 841
 842 Mixer::OutputFrameInfo Mixer::get_one_frame_from_each_card(unsigned master_card_index, bool master_card_is_output, CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS], bool has_new_frame[MAX_VIDEO_CARDS])
 843 {
 844         OutputFrameInfo output_frame_info;
 845 start:
 846         unique_lock<mutex> lock(card_mutex, defer_lock);
 847         if (master_card_is_output) {
 848                 // Clocked to the output, so wait for it to be ready for the next frame.
 849                 cards[master_card_index].output->wait_for_frame(pts_int, &output_frame_info.dropped_frames, &output_frame_info.frame_duration, &output_frame_info.is_preroll, &output_frame_info.frame_timestamp);
 850                 lock.lock();
 851         } else {
 852                 // Wait for the master card to have a new frame.
 853                 // TODO: Add a timeout.
 854                 output_frame_info.is_preroll = false;
 855                 lock.lock();
 856                 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(); });
 857         }
 858
 859         if (master_card_is_output) {
 860                 handle_hotplugged_cards();
 861         } else if (cards[master_card_index].new_frames.empty()) {
 862                 // We were woken up, but not due to a new frame. Deal with it
 863                 // and then restart.
 864                 assert(cards[master_card_index].capture->get_disconnected());
 865                 handle_hotplugged_cards();
 866                 goto start;
 867         }
 868
 869         if (!master_card_is_output) {
 870                 output_frame_info.frame_timestamp =
 871                         cards[master_card_index].new_frames.front().received_timestamp;
 872         }
 873
 874         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 875                 CaptureCard *card = &cards[card_index];
 876                 if (input_card_is_master_clock(card_index, master_card_index)) {
 877                         // We don't use the queue length policy for the master card,
 878                         // but we will if it stops being the master. Thus, clear out
 879                         // the policy in case we switch in the future.
 880                         card->queue_length_policy.reset(card_index);
 881                         assert(!card->new_frames.empty());
 882                 } else {
 883                         trim_queue(card, card_index);
 884                 }
 885                 if (!card->new_frames.empty()) {
 886                         new_frames[card_index] = move(card->new_frames.front());
 887                         has_new_frame[card_index] = true;
 888                         card->new_frames.pop_front();
 889                         card->new_frames_changed.notify_all();
 890                 }
 891         }
 892
 893         if (!master_card_is_output) {
 894                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
 895                 output_frame_info.frame_duration = new_frames[master_card_index].length;
 896         }
 897
 898         // This might get off by a fractional sample when changing master card
 899         // between ones with different frame rates, but that's fine.
 900         int num_samples_times_timebase = OUTPUT_FREQUENCY * output_frame_info.frame_duration + fractional_samples;
 901         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
 902         fractional_samples = num_samples_times_timebase % TIMEBASE;
 903         assert(output_frame_info.num_samples >= 0);
 904
 905         return output_frame_info;
 906 }
 907
 908 void Mixer::handle_hotplugged_cards()
 909 {
 910         // Check for cards that have been disconnected since last frame.
 911         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 912                 CaptureCard *card = &cards[card_index];
 913                 if (card->capture->get_disconnected()) {
 914                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
 915                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 916                         configure_card(card_index, capture, /*is_fake_capture=*/true, /*output=*/nullptr);
 917                         card->queue_length_policy.reset(card_index);
 918                         card->capture->start_bm_capture();
 919                 }
 920         }
 921
 922         // Check for cards that have been connected since last frame.
 923         vector<libusb_device *> hotplugged_cards_copy;
 924         {
 925                 lock_guard<mutex> lock(hotplug_mutex);
 926                 swap(hotplugged_cards, hotplugged_cards_copy);
 927         }
 928         for (libusb_device *new_dev : hotplugged_cards_copy) {
 929                 // Look for a fake capture card where we can stick this in.
 930                 int free_card_index = -1;
 931                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 932                         if (cards[card_index].is_fake_capture) {
 933                                 free_card_index = card_index;
 934                                 break;
 935                         }
 936                 }
 937
 938                 if (free_card_index == -1) {
 939                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
 940                         libusb_unref_device(new_dev);
 941                 } else {
 942                         // BMUSBCapture takes ownership.
 943                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
 944                         CaptureCard *card = &cards[free_card_index];
 945                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
 946                         configure_card(free_card_index, capture, /*is_fake_capture=*/false, /*output=*/nullptr);
 947                         card->queue_length_policy.reset(free_card_index);
 948                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
 949                         capture->start_bm_capture();
 950                 }
 951         }
 952 }
 953
 954
 955 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame, bool is_preroll, steady_clock::time_point frame_timestamp)
 956 {
 957         // Resample the audio as needed, including from previously dropped frames.
 958         assert(num_cards > 0);
 959         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
 960                 const bool dropped_frame = (frame_num != dropped_frames);
 961                 {
 962                         // Signal to the audio thread to process this frame.
 963                         // Note that if the frame is a dropped frame, we signal that
 964                         // we don't want to use this frame as base for adjusting
 965                         // the resampler rate. The reason for this is that the timing
 966                         // of these frames is often way too late; they typically don't
 967                         // “arrive” before we synthesize them. Thus, we could end up
 968                         // in a situation where we have inserted e.g. five audio frames
 969                         // into the queue before we then start pulling five of them
 970                         // back out. This makes ResamplingQueue overestimate the delay,
 971                         // causing undue resampler changes. (We _do_ use the last,
 972                         // non-dropped frame; perhaps we should just discard that as well,
 973                         // since dropped frames are expected to be rare, and it might be
 974                         // better to just wait until we have a slightly more normal situation).
 975                         unique_lock<mutex> lock(audio_mutex);
 976                         bool adjust_rate = !dropped_frame && !is_preroll;
 977                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
 978                         audio_task_queue_changed.notify_one();
 979                 }
 980                 if (dropped_frame) {
 981                         // For dropped frames, increase the pts. Note that if the format changed
 982                         // in the meantime, we have no way of detecting that; we just have to
 983                         // assume the frame length is always the same.
 984                         pts_int += length_per_frame;
 985                 }
 986         }
 987 }
 988
 989 void Mixer::render_one_frame(int64_t duration)
 990 {
 991         // Determine the time code for this frame before we start rendering.
 992         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
 993         if (display_timecode_on_stdout) {
 994                 printf("Timecode: '%s'\n", timecode_text.c_str());
 995         }
 996
 997         // Get the main chain from the theme, and set its state immediately.
 998         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
 999         EffectChain *chain = theme_main_chain.chain;
1000         theme_main_chain.setup_chain();
1001         //theme_main_chain.chain->enable_phase_timing(true);
1002
1003         GLuint y_tex, cbcr_tex;
1004         bool got_frame = video_encoder->begin_frame(&y_tex, &cbcr_tex);
1005         assert(got_frame);
1006
1007         // Render main chain.
1008         GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, global_flags.width, global_flags.height);
1009         GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, global_flags.width, global_flags.height);  // Saves texture bandwidth, although dithering gets messed up.
1010         GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
1011         check_error();
1012         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1013
1014         if (display_timecode_in_stream) {
1015                 // Render the timecode on top.
1016                 timecode_renderer->render_timecode(fbo, timecode_text);
1017         }
1018
1019         resource_pool->release_fbo(fbo);
1020
1021         chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1022         if (output_card_index != -1) {
1023                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, theme_main_chain.input_frames, pts_int, duration);
1024         }
1025         resource_pool->release_2d_texture(cbcr_full_tex);
1026
1027         // Set the right state for rgba_tex.
1028         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1029         glBindTexture(GL_TEXTURE_2D, rgba_tex);
1030         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1031         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1032         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1033
1034         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1035         RefCountedGLsync fence = video_encoder->end_frame(pts_int + av_delay, duration, theme_main_chain.input_frames);
1036
1037         // The live frame just shows the RGBA texture we just rendered.
1038         // It owns rgba_tex now.
1039         DisplayFrame live_frame;
1040         live_frame.chain = display_chain.get();
1041         live_frame.setup_chain = [this, rgba_tex]{
1042                 display_input->set_texture_num(rgba_tex);
1043         };
1044         live_frame.ready_fence = fence;
1045         live_frame.input_frames = {};
1046         live_frame.temp_textures = { rgba_tex };
1047         output_channel[OUTPUT_LIVE].output_frame(live_frame);
1048
1049         // Set up preview and any additional channels.
1050         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1051                 DisplayFrame display_frame;
1052                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1053                 display_frame.chain = chain.chain;
1054                 display_frame.setup_chain = chain.setup_chain;
1055                 display_frame.ready_fence = fence;
1056                 display_frame.input_frames = chain.input_frames;
1057                 display_frame.temp_textures = {};
1058                 output_channel[i].output_frame(display_frame);
1059         }
1060 }
1061
1062 void Mixer::audio_thread_func()
1063 {
1064         pthread_setname_np(pthread_self(), "Mixer_Audio");
1065
1066         while (!should_quit) {
1067                 AudioTask task;
1068
1069                 {
1070                         unique_lock<mutex> lock(audio_mutex);
1071                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1072                         if (should_quit) {
1073                                 return;
1074                         }
1075                         task = audio_task_queue.front();
1076                         audio_task_queue.pop();
1077                 }
1078
1079                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1080                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1081                 vector<float> samples_out = audio_mixer.get_output(
1082                         task.frame_timestamp,
1083                         task.num_samples,
1084                         rate_adjustment_policy);
1085
1086                 // Send the samples to the sound card, then add them to the output.
1087                 if (alsa) {
1088                         alsa->write(samples_out);
1089                 }
1090                 if (output_card_index != -1) {
1091                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1092                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1093                 }
1094                 video_encoder->add_audio(task.pts_int, move(samples_out));
1095         }
1096 }
1097
1098 void Mixer::release_display_frame(DisplayFrame *frame)
1099 {
1100         for (GLuint texnum : frame->temp_textures) {
1101                 resource_pool->release_2d_texture(texnum);
1102         }
1103         frame->temp_textures.clear();
1104         frame->ready_fence.reset();
1105         frame->input_frames.clear();
1106 }
1107
1108 void Mixer::start()
1109 {
1110         mixer_thread = thread(&Mixer::thread_func, this);
1111         audio_thread = thread(&Mixer::audio_thread_func, this);
1112 }
1113
1114 void Mixer::quit()
1115 {
1116         should_quit = true;
1117         audio_task_queue_changed.notify_one();
1118         mixer_thread.join();
1119         audio_thread.join();
1120 }
1121
1122 void Mixer::transition_clicked(int transition_num)
1123 {
1124         theme->transition_clicked(transition_num, pts());
1125 }
1126
1127 void Mixer::channel_clicked(int preview_num)
1128 {
1129         theme->channel_clicked(preview_num);
1130 }
1131
1132 void Mixer::start_mode_scanning(unsigned card_index)
1133 {
1134         assert(card_index < num_cards);
1135         if (is_mode_scanning[card_index]) {
1136                 return;
1137         }
1138         is_mode_scanning[card_index] = true;
1139         mode_scanlist[card_index].clear();
1140         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1141                 mode_scanlist[card_index].push_back(mode.first);
1142         }
1143         assert(!mode_scanlist[card_index].empty());
1144         mode_scanlist_index[card_index] = 0;
1145         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1146         last_mode_scan_change[card_index] = steady_clock::now();
1147 }
1148
1149 map<uint32_t, bmusb::VideoMode> Mixer::get_available_output_video_modes() const
1150 {
1151         assert(desired_output_card_index != -1);
1152         unique_lock<mutex> lock(card_mutex);
1153         return cards[desired_output_card_index].output->get_available_video_modes();
1154 }
1155
1156 Mixer::OutputChannel::~OutputChannel()
1157 {
1158         if (has_current_frame) {
1159                 parent->release_display_frame(&current_frame);
1160         }
1161         if (has_ready_frame) {
1162                 parent->release_display_frame(&ready_frame);
1163         }
1164 }
1165
1166 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1167 {
1168         // Store this frame for display. Remove the ready frame if any
1169         // (it was seemingly never used).
1170         {
1171                 unique_lock<mutex> lock(frame_mutex);
1172                 if (has_ready_frame) {
1173                         parent->release_display_frame(&ready_frame);
1174                 }
1175                 ready_frame = frame;
1176                 has_ready_frame = true;
1177         }
1178
1179         if (new_frame_ready_callback) {
1180                 new_frame_ready_callback();
1181         }
1182
1183         // Reduce the number of callbacks by filtering duplicates. The reason
1184         // why we bother doing this is that Qt seemingly can get into a state
1185         // where its builds up an essentially unbounded queue of signals,
1186         // consuming more and more memory, and there's no good way of collapsing
1187         // user-defined signals or limiting the length of the queue.
1188         if (transition_names_updated_callback) {
1189                 vector<string> transition_names = global_mixer->get_transition_names();
1190                 bool changed = false;
1191                 if (transition_names.size() != last_transition_names.size()) {
1192                         changed = true;
1193                 } else {
1194                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1195                                 if (transition_names[i] != last_transition_names[i]) {
1196                                         changed = true;
1197                                         break;
1198                                 }
1199                         }
1200                 }
1201                 if (changed) {
1202                         transition_names_updated_callback(transition_names);
1203                         last_transition_names = transition_names;
1204                 }
1205         }
1206         if (name_updated_callback) {
1207                 string name = global_mixer->get_channel_name(channel);
1208                 if (name != last_name) {
1209                         name_updated_callback(name);
1210                         last_name = name;
1211                 }
1212         }
1213         if (color_updated_callback) {
1214                 string color = global_mixer->get_channel_color(channel);
1215                 if (color != last_color) {
1216                         color_updated_callback(color);
1217                         last_color = color;
1218                 }
1219         }
1220 }
1221
1222 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1223 {
1224         unique_lock<mutex> lock(frame_mutex);
1225         if (!has_current_frame && !has_ready_frame) {
1226                 return false;
1227         }
1228
1229         if (has_current_frame && has_ready_frame) {
1230                 // We have a new ready frame. Toss the current one.
1231                 parent->release_display_frame(&current_frame);
1232                 has_current_frame = false;
1233         }
1234         if (has_ready_frame) {
1235                 assert(!has_current_frame);
1236                 current_frame = ready_frame;
1237                 ready_frame.ready_fence.reset();  // Drop the refcount.
1238                 ready_frame.input_frames.clear();  // Drop the refcounts.
1239                 has_current_frame = true;
1240                 has_ready_frame = false;
1241         }
1242
1243         *frame = current_frame;
1244         return true;
1245 }
1246
1247 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1248 {
1249         new_frame_ready_callback = callback;
1250 }
1251
1252 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1253 {
1254         transition_names_updated_callback = callback;
1255 }
1256
1257 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1258 {
1259         name_updated_callback = callback;
1260 }
1261
1262 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1263 {
1264         color_updated_callback = callback;
1265 }
1266
1267 mutex RefCountedGLsync::fence_lock;