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 "ffmpeg_capture.h"
  43 #include "flags.h"
  44 #include "input_mapping.h"
  45 #include "metrics.h"
  46 #include "pbo_frame_allocator.h"
  47 #include "ref_counted_gl_sync.h"
  48 #include "resampling_queue.h"
  49 #include "timebase.h"
  50 #include "timecode_renderer.h"
  51 #include "v210_converter.h"
  52 #include "video_encoder.h"
  53
  54 class IDeckLink;
  55 class QOpenGLContext;
  56
  57 using namespace movit;
  58 using namespace std;
  59 using namespace std::chrono;
  60 using namespace std::placeholders;
  61 using namespace bmusb;
  62
  63 Mixer *global_mixer = nullptr;
  64 bool uses_mlock = false;
  65
  66 namespace {
  67
  68 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  69 {
  70         if (interlaced) {
  71                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  72                         input_state->buffered_frames[card_index][frame_num] =
  73                                 input_state->buffered_frames[card_index][frame_num - 1];
  74                 }
  75                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  76         } else {
  77                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  78                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  79                 }
  80         }
  81 }
  82
  83 void ensure_texture_resolution(PBOFrameAllocator::Userdata *userdata, unsigned field, unsigned width, unsigned height, unsigned cbcr_width, unsigned cbcr_height, unsigned v210_width)
  84 {
  85         bool first;
  86         switch (userdata->pixel_format) {
  87         case PixelFormat_10BitYCbCr:
  88                 first = userdata->tex_v210[field] == 0 || userdata->tex_444[field] == 0;
  89                 break;
  90         case PixelFormat_8BitYCbCr:
  91                 first = userdata->tex_y[field] == 0 || userdata->tex_cbcr[field] == 0;
  92                 break;
  93         case PixelFormat_8BitBGRA:
  94                 first = userdata->tex_rgba[field] == 0;
  95                 break;
  96         case PixelFormat_8BitYCbCrPlanar:
  97                 first = userdata->tex_y[field] == 0 || userdata->tex_cb[field] == 0 || userdata->tex_cr[field] == 0;
  98                 break;
  99         default:
 100                 assert(false);
 101         }
 102
 103         if (first ||
 104             width != userdata->last_width[field] ||
 105             height != userdata->last_height[field] ||
 106             cbcr_width != userdata->last_cbcr_width[field] ||
 107             cbcr_height != userdata->last_cbcr_height[field]) {
 108                 // We changed resolution since last use of this texture, so we need to create
 109                 // a new object. Note that this each card has its own PBOFrameAllocator,
 110                 // we don't need to worry about these flip-flopping between resolutions.
 111                 switch (userdata->pixel_format) {
 112                 case PixelFormat_10BitYCbCr:
 113                         glBindTexture(GL_TEXTURE_2D, userdata->tex_444[field]);
 114                         check_error();
 115                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 116                         check_error();
 117                         break;
 118                 case PixelFormat_8BitYCbCr: {
 119                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 120                         check_error();
 121                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 122                         check_error();
 123                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 124                         check_error();
 125                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 126                         check_error();
 127                         break;
 128                 }
 129                 case PixelFormat_8BitYCbCrPlanar: {
 130                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 131                         check_error();
 132                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 133                         check_error();
 134                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cb[field]);
 135                         check_error();
 136                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 137                         check_error();
 138                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cr[field]);
 139                         check_error();
 140                         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, cbcr_width, cbcr_height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 141                         check_error();
 142                         break;
 143                 }
 144                 case PixelFormat_8BitBGRA:
 145                         glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
 146                         check_error();
 147                         if (global_flags.can_disable_srgb_decoder) {  // See the comments in tweaked_inputs.h.
 148                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
 149                         } else {
 150                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr);
 151                         }
 152                         check_error();
 153                         break;
 154                 }
 155                 userdata->last_width[field] = width;
 156                 userdata->last_height[field] = height;
 157                 userdata->last_cbcr_width[field] = cbcr_width;
 158                 userdata->last_cbcr_height[field] = cbcr_height;
 159         }
 160         if (global_flags.ten_bit_input &&
 161             (first || v210_width != userdata->last_v210_width[field])) {
 162                 // Same as above; we need to recreate the texture.
 163                 glBindTexture(GL_TEXTURE_2D, userdata->tex_v210[field]);
 164                 check_error();
 165                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB10_A2, v210_width, height, 0, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, nullptr);
 166                 check_error();
 167                 userdata->last_v210_width[field] = v210_width;
 168         }
 169 }
 170
 171 void upload_texture(GLuint tex, GLuint width, GLuint height, GLuint stride, bool interlaced_stride, GLenum format, GLenum type, GLintptr offset)
 172 {
 173         if (interlaced_stride) {
 174                 stride *= 2;
 175         }
 176         if (global_flags.flush_pbos) {
 177                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, offset, stride * height);
 178                 check_error();
 179         }
 180
 181         glBindTexture(GL_TEXTURE_2D, tex);
 182         check_error();
 183         if (interlaced_stride) {
 184                 glPixelStorei(GL_UNPACK_ROW_LENGTH, width * 2);
 185                 check_error();
 186         } else {
 187                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 188                 check_error();
 189         }
 190
 191         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(offset));
 192         check_error();
 193         glBindTexture(GL_TEXTURE_2D, 0);
 194         check_error();
 195         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 196         check_error();
 197 }
 198
 199 }  // namespace
 200
 201 void JitterHistory::register_metrics(const vector<pair<string, string>> &labels)
 202 {
 203         global_metrics.add("input_underestimated_jitter_frames", labels, &metric_input_underestimated_jitter_frames);
 204         global_metrics.add("input_estimated_max_jitter_seconds", labels, &metric_input_estimated_max_jitter_seconds, Metrics::TYPE_GAUGE);
 205 }
 206
 207 void JitterHistory::unregister_metrics(const vector<pair<string, string>> &labels)
 208 {
 209         global_metrics.remove("input_underestimated_jitter_frames", labels);
 210         global_metrics.remove("input_estimated_max_jitter_seconds", labels);
 211 }
 212
 213 void JitterHistory::frame_arrived(steady_clock::time_point now, int64_t frame_duration, size_t dropped_frames)
 214 {
 215         if (expected_timestamp > steady_clock::time_point::min()) {
 216                 expected_timestamp += dropped_frames * nanoseconds(frame_duration * 1000000000 / TIMEBASE);
 217                 double jitter_seconds = fabs(duration<double>(expected_timestamp - now).count());
 218                 history.push_back(orders.insert(jitter_seconds));
 219                 if (jitter_seconds > estimate_max_jitter()) {
 220                         ++metric_input_underestimated_jitter_frames;
 221                 }
 222
 223                 metric_input_estimated_max_jitter_seconds = estimate_max_jitter();
 224
 225                 if (history.size() > history_length) {
 226                         orders.erase(history.front());
 227                         history.pop_front();
 228                 }
 229                 assert(history.size() <= history_length);
 230         }
 231         expected_timestamp = now + nanoseconds(frame_duration * 1000000000 / TIMEBASE);
 232 }
 233
 234 double JitterHistory::estimate_max_jitter() const
 235 {
 236         if (orders.empty()) {
 237                 return 0.0;
 238         }
 239         size_t elem_idx = lrint((orders.size() - 1) * percentile);
 240         if (percentile <= 0.5) {
 241                 return *next(orders.begin(), elem_idx) * multiplier;
 242         } else {
 243                 return *prev(orders.end(), elem_idx + 1) * multiplier;
 244         }
 245 }
 246
 247 void QueueLengthPolicy::register_metrics(const vector<pair<string, string>> &labels)
 248 {
 249         global_metrics.add("input_queue_safe_length_frames", labels, &metric_input_queue_safe_length_frames, Metrics::TYPE_GAUGE);
 250 }
 251
 252 void QueueLengthPolicy::unregister_metrics(const vector<pair<string, string>> &labels)
 253 {
 254         global_metrics.remove("input_queue_safe_length_frames", labels);
 255 }
 256
 257 void QueueLengthPolicy::update_policy(steady_clock::time_point now,
 258                                       steady_clock::time_point expected_next_frame,
 259                                       int64_t input_frame_duration,
 260                                       int64_t master_frame_duration,
 261                                       double max_input_card_jitter_seconds,
 262                                       double max_master_card_jitter_seconds)
 263 {
 264         double input_frame_duration_seconds = input_frame_duration / double(TIMEBASE);
 265         double master_frame_duration_seconds = master_frame_duration / double(TIMEBASE);
 266
 267         // Figure out when we can expect the next frame for this card, assuming
 268         // worst-case jitter (ie., the frame is maximally late).
 269         double seconds_until_next_frame = max(duration<double>(expected_next_frame - now).count() + max_input_card_jitter_seconds, 0.0);
 270
 271         // How many times are the master card expected to tick in that time?
 272         // We assume the master clock has worst-case jitter but not any rate
 273         // discrepancy, ie., it ticks as early as possible every time, but not
 274         // cumulatively.
 275         double frames_needed = (seconds_until_next_frame + max_master_card_jitter_seconds) / master_frame_duration_seconds;
 276
 277         // As a special case, if the master card ticks faster than the input card,
 278         // we expect the queue to drain by itself even without dropping. But if
 279         // the difference is small (e.g. 60 Hz master and 59.94 input), it would
 280         // go slowly enough that the effect wouldn't really be appreciable.
 281         // We account for this by looking at the situation five frames ahead,
 282         // assuming everything else is the same.
 283         double frames_allowed;
 284         if (master_frame_duration < input_frame_duration) {
 285                 frames_allowed = frames_needed + 5 * (input_frame_duration_seconds - master_frame_duration_seconds) / master_frame_duration_seconds;
 286         } else {
 287                 frames_allowed = frames_needed;
 288         }
 289
 290         safe_queue_length = max<int>(floor(frames_allowed), 0);
 291         metric_input_queue_safe_length_frames = safe_queue_length;
 292 }
 293
 294 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 295         : httpd(),
 296           num_cards(num_cards),
 297           mixer_surface(create_surface(format)),
 298           h264_encoder_surface(create_surface(format)),
 299           decklink_output_surface(create_surface(format)),
 300           audio_mixer(num_cards)
 301 {
 302         memcpy(ycbcr_interpretation, global_flags.ycbcr_interpretation, sizeof(ycbcr_interpretation));
 303         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 304         check_error();
 305
 306         // This nearly always should be true.
 307         global_flags.can_disable_srgb_decoder =
 308                 epoxy_has_gl_extension("GL_EXT_texture_sRGB_decode") &&
 309                 epoxy_has_gl_extension("GL_ARB_sampler_objects");
 310
 311         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 312         // will be halved when sampling them, and we need to compensate here.
 313         movit_texel_subpixel_precision /= 2.0;
 314
 315         resource_pool.reset(new ResourcePool);
 316         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 317                 output_channel[i].parent = this;
 318                 output_channel[i].channel = i;
 319         }
 320
 321         ImageFormat inout_format;
 322         inout_format.color_space = COLORSPACE_sRGB;
 323         inout_format.gamma_curve = GAMMA_sRGB;
 324
 325         // Matches the 4:2:0 format created by the main chain.
 326         YCbCrFormat ycbcr_format;
 327         ycbcr_format.chroma_subsampling_x = 2;
 328         ycbcr_format.chroma_subsampling_y = 2;
 329         if (global_flags.ycbcr_rec709_coefficients) {
 330                 ycbcr_format.luma_coefficients = YCBCR_REC_709;
 331         } else {
 332                 ycbcr_format.luma_coefficients = YCBCR_REC_601;
 333         }
 334         ycbcr_format.full_range = false;
 335         ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
 336         ycbcr_format.cb_x_position = 0.0f;
 337         ycbcr_format.cr_x_position = 0.0f;
 338         ycbcr_format.cb_y_position = 0.5f;
 339         ycbcr_format.cr_y_position = 0.5f;
 340
 341         // Display chain; shows the live output produced by the main chain (or rather, a copy of it).
 342         display_chain.reset(new EffectChain(global_flags.width, global_flags.height, resource_pool.get()));
 343         check_error();
 344         GLenum type = global_flags.x264_bit_depth > 8 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_BYTE;
 345         display_input = new YCbCrInput(inout_format, ycbcr_format, global_flags.width, global_flags.height, YCBCR_INPUT_SPLIT_Y_AND_CBCR, type);
 346         display_chain->add_input(display_input);
 347         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 348         display_chain->set_dither_bits(0);  // Don't bother.
 349         display_chain->finalize();
 350
 351         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));
 352
 353         // Must be instantiated after VideoEncoder has initialized global_flags.use_zerocopy.
 354         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
 355
 356         // Start listening for clients only once VideoEncoder has written its header, if any.
 357         httpd.start(9095);
 358
 359         // First try initializing the then PCI devices, then USB, then
 360         // fill up with fake cards until we have the desired number of cards.
 361         unsigned num_pci_devices = 0;
 362         unsigned card_index = 0;
 363
 364         {
 365                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 366                 if (decklink_iterator != nullptr) {
 367                         for ( ; card_index < num_cards; ++card_index) {
 368                                 IDeckLink *decklink;
 369                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 370                                         break;
 371                                 }
 372
 373                                 DeckLinkCapture *capture = new DeckLinkCapture(decklink, card_index);
 374                                 DeckLinkOutput *output = new DeckLinkOutput(resource_pool.get(), decklink_output_surface, global_flags.width, global_flags.height, card_index);
 375                                 output->set_device(decklink);
 376                                 configure_card(card_index, capture, CardType::LIVE_CARD, output);
 377                                 ++num_pci_devices;
 378                         }
 379                         decklink_iterator->Release();
 380                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 381                 } else {
 382                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 383                 }
 384         }
 385
 386         unsigned num_usb_devices = BMUSBCapture::num_cards();
 387         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
 388                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 389                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 390                 configure_card(card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
 391         }
 392         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 393
 394         unsigned num_fake_cards = 0;
 395         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
 396                 FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 397                 configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
 398         }
 399
 400         if (num_fake_cards > 0) {
 401                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 402         }
 403
 404         // Initialize all video inputs the theme asked for. Note that these are
 405         // all put _after_ the regular cards, which stop at <num_cards> - 1.
 406         std::vector<FFmpegCapture *> video_inputs = theme->get_video_inputs();
 407         for (unsigned video_card_index = 0; video_card_index < video_inputs.size(); ++card_index, ++video_card_index) {
 408                 if (card_index >= MAX_VIDEO_CARDS) {
 409                         fprintf(stderr, "ERROR: Not enough card slots available for the videos the theme requested.\n");
 410                         exit(1);
 411                 }
 412                 configure_card(card_index, video_inputs[video_card_index], CardType::FFMPEG_INPUT, /*output=*/nullptr);
 413                 video_inputs[video_card_index]->set_card_index(card_index);
 414         }
 415         num_video_inputs = video_inputs.size();
 416
 417         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 418         BMUSBCapture::start_bm_thread();
 419
 420         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
 421                 cards[card_index].queue_length_policy.reset(card_index);
 422         }
 423
 424         chroma_subsampler.reset(new ChromaSubsampler(resource_pool.get()));
 425
 426         if (global_flags.ten_bit_input) {
 427                 if (!v210Converter::has_hardware_support()) {
 428                         fprintf(stderr, "ERROR: --ten-bit-input requires support for OpenGL compute shaders\n");
 429                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 430                         exit(1);
 431                 }
 432                 v210_converter.reset(new v210Converter());
 433
 434                 // These are all the widths listed in the Blackmagic SDK documentation
 435                 // (section 2.7.3, “Display Modes”).
 436                 v210_converter->precompile_shader(720);
 437                 v210_converter->precompile_shader(1280);
 438                 v210_converter->precompile_shader(1920);
 439                 v210_converter->precompile_shader(2048);
 440                 v210_converter->precompile_shader(3840);
 441                 v210_converter->precompile_shader(4096);
 442         }
 443         if (global_flags.ten_bit_output) {
 444                 if (!v210Converter::has_hardware_support()) {
 445                         fprintf(stderr, "ERROR: --ten-bit-output requires support for OpenGL compute shaders\n");
 446                         fprintf(stderr, "       (OpenGL 4.3, or GL_ARB_compute_shader + GL_ARB_shader_image_load_store).\n");
 447                         exit(1);
 448                 }
 449         }
 450
 451         timecode_renderer.reset(new TimecodeRenderer(resource_pool.get(), global_flags.width, global_flags.height));
 452         display_timecode_in_stream = global_flags.display_timecode_in_stream;
 453         display_timecode_on_stdout = global_flags.display_timecode_on_stdout;
 454
 455         if (global_flags.enable_alsa_output) {
 456                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 457         }
 458         if (global_flags.output_card != -1) {
 459                 desired_output_card_index = global_flags.output_card;
 460                 set_output_card_internal(global_flags.output_card);
 461         }
 462
 463         metric_start_time_seconds = get_timestamp_for_metrics();
 464
 465         output_jitter_history.register_metrics({{ "card", "output" }});
 466         global_metrics.add("frames_output_total", &metric_frames_output_total);
 467         global_metrics.add("frames_output_dropped", &metric_frames_output_dropped);
 468         global_metrics.add("start_time_seconds", &metric_start_time_seconds, Metrics::TYPE_GAUGE);
 469         global_metrics.add("memory_used_bytes", &metrics_memory_used_bytes);
 470         global_metrics.add("memory_locked_limit_bytes", &metrics_memory_locked_limit_bytes);
 471 }
 472
 473 Mixer::~Mixer()
 474 {
 475         BMUSBCapture::stop_bm_thread();
 476
 477         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
 478                 {
 479                         unique_lock<mutex> lock(card_mutex);
 480                         cards[card_index].should_quit = true;  // Unblock thread.
 481                         cards[card_index].new_frames_changed.notify_all();
 482                 }
 483                 cards[card_index].capture->stop_dequeue_thread();
 484                 if (cards[card_index].output) {
 485                         cards[card_index].output->end_output();
 486                         cards[card_index].output.reset();
 487                 }
 488         }
 489
 490         video_encoder.reset(nullptr);
 491 }
 492
 493 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, CardType card_type, DeckLinkOutput *output)
 494 {
 495         printf("Configuring card %d...\n", card_index);
 496
 497         CaptureCard *card = &cards[card_index];
 498         if (card->capture != nullptr) {
 499                 card->capture->stop_dequeue_thread();
 500         }
 501         card->capture.reset(capture);
 502         card->is_fake_capture = (card_type == CardType::FAKE_CAPTURE);
 503         card->type = card_type;
 504         if (card->output.get() != output) {
 505                 card->output.reset(output);
 506         }
 507
 508         PixelFormat pixel_format;
 509         if (card_type == CardType::FFMPEG_INPUT) {
 510                 pixel_format = capture->get_current_pixel_format();
 511         } else if (global_flags.ten_bit_input) {
 512                 pixel_format = PixelFormat_10BitYCbCr;
 513         } else {
 514                 pixel_format = PixelFormat_8BitYCbCr;
 515         }
 516
 517         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 518         if (card->frame_allocator == nullptr) {
 519                 card->frame_allocator.reset(new PBOFrameAllocator(pixel_format, 8 << 20, global_flags.width, global_flags.height));  // 8 MB.
 520         }
 521         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 522         if (card->surface == nullptr) {
 523                 card->surface = create_surface_with_same_format(mixer_surface);
 524         }
 525         while (!card->new_frames.empty()) card->new_frames.pop_front();
 526         card->last_timecode = -1;
 527         card->capture->set_pixel_format(pixel_format);
 528         card->capture->configure_card();
 529
 530         // NOTE: start_bm_capture() happens in thread_func().
 531
 532         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 533         audio_mixer.reset_resampler(device);
 534         audio_mixer.set_display_name(device, card->capture->get_description());
 535         audio_mixer.trigger_state_changed_callback();
 536
 537         // Unregister old metrics, if any.
 538         if (!card->labels.empty()) {
 539                 const vector<pair<string, string>> &labels = card->labels;
 540                 card->jitter_history.unregister_metrics(labels);
 541                 card->queue_length_policy.unregister_metrics(labels);
 542                 global_metrics.remove("input_received_frames", labels);
 543                 global_metrics.remove("input_dropped_frames_jitter", labels);
 544                 global_metrics.remove("input_dropped_frames_error", labels);
 545                 global_metrics.remove("input_dropped_frames_resets", labels);
 546                 global_metrics.remove("input_queue_length_frames", labels);
 547                 global_metrics.remove("input_queue_duped_frames", labels);
 548
 549                 global_metrics.remove("input_has_signal_bool", labels);
 550                 global_metrics.remove("input_is_connected_bool", labels);
 551                 global_metrics.remove("input_interlaced_bool", labels);
 552                 global_metrics.remove("input_width_pixels", labels);
 553                 global_metrics.remove("input_height_pixels", labels);
 554                 global_metrics.remove("input_frame_rate_nom", labels);
 555                 global_metrics.remove("input_frame_rate_den", labels);
 556                 global_metrics.remove("input_sample_rate_hz", labels);
 557         }
 558
 559         // Register metrics.
 560         vector<pair<string, string>> labels;
 561         char card_name[64];
 562         snprintf(card_name, sizeof(card_name), "%d", card_index);
 563         labels.emplace_back("card", card_name);
 564
 565         switch (card_type) {
 566         case CardType::LIVE_CARD:
 567                 labels.emplace_back("cardtype", "live");
 568                 break;
 569         case CardType::FAKE_CAPTURE:
 570                 labels.emplace_back("cardtype", "fake");
 571                 break;
 572         case CardType::FFMPEG_INPUT:
 573                 labels.emplace_back("cardtype", "ffmpeg");
 574                 break;
 575         default:
 576                 assert(false);
 577         }
 578         card->jitter_history.register_metrics(labels);
 579         card->queue_length_policy.register_metrics(labels);
 580         global_metrics.add("input_received_frames", labels, &card->metric_input_received_frames);
 581         global_metrics.add("input_dropped_frames_jitter", labels, &card->metric_input_dropped_frames_jitter);
 582         global_metrics.add("input_dropped_frames_error", labels, &card->metric_input_dropped_frames_error);
 583         global_metrics.add("input_dropped_frames_resets", labels, &card->metric_input_resets);
 584         global_metrics.add("input_queue_length_frames", labels, &card->metric_input_queue_length_frames, Metrics::TYPE_GAUGE);
 585         global_metrics.add("input_queue_duped_frames", labels, &card->metric_input_duped_frames);
 586
 587         global_metrics.add("input_has_signal_bool", labels, &card->metric_input_has_signal_bool, Metrics::TYPE_GAUGE);
 588         global_metrics.add("input_is_connected_bool", labels, &card->metric_input_is_connected_bool, Metrics::TYPE_GAUGE);
 589         global_metrics.add("input_interlaced_bool", labels, &card->metric_input_interlaced_bool, Metrics::TYPE_GAUGE);
 590         global_metrics.add("input_width_pixels", labels, &card->metric_input_width_pixels, Metrics::TYPE_GAUGE);
 591         global_metrics.add("input_height_pixels", labels, &card->metric_input_height_pixels, Metrics::TYPE_GAUGE);
 592         global_metrics.add("input_frame_rate_nom", labels, &card->metric_input_frame_rate_nom, Metrics::TYPE_GAUGE);
 593         global_metrics.add("input_frame_rate_den", labels, &card->metric_input_frame_rate_den, Metrics::TYPE_GAUGE);
 594         global_metrics.add("input_sample_rate_hz", labels, &card->metric_input_sample_rate_hz, Metrics::TYPE_GAUGE);
 595         card->labels = labels;
 596 }
 597
 598 void Mixer::set_output_card_internal(int card_index)
 599 {
 600         // We don't really need to take card_mutex, since we're in the mixer
 601         // thread and don't mess with any queues (which is the only thing that happens
 602         // from other threads), but it's probably the safest in the long run.
 603         unique_lock<mutex> lock(card_mutex);
 604         if (output_card_index != -1) {
 605                 // Switch the old card from output to input.
 606                 CaptureCard *old_card = &cards[output_card_index];
 607                 old_card->output->end_output();
 608
 609                 // Stop the fake card that we put into place.
 610                 // This needs to _not_ happen under the mutex, to avoid deadlock
 611                 // (delivering the last frame needs to take the mutex).
 612                 CaptureInterface *fake_capture = old_card->capture.get();
 613                 lock.unlock();
 614                 fake_capture->stop_dequeue_thread();
 615                 lock.lock();
 616                 old_card->capture = move(old_card->parked_capture);  // TODO: reset the metrics
 617                 old_card->is_fake_capture = false;
 618                 old_card->capture->start_bm_capture();
 619         }
 620         if (card_index != -1) {
 621                 CaptureCard *card = &cards[card_index];
 622                 CaptureInterface *capture = card->capture.get();
 623                 // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
 624                 // several seconds to complete (blocking on DisableVideoInput);
 625                 // see if we can maybe do it asynchronously.
 626                 lock.unlock();
 627                 capture->stop_dequeue_thread();
 628                 lock.lock();
 629                 card->parked_capture = move(card->capture);
 630                 CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 631                 configure_card(card_index, fake_capture, CardType::FAKE_CAPTURE, card->output.release());
 632                 card->queue_length_policy.reset(card_index);
 633                 card->capture->start_bm_capture();
 634                 desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
 635                 card->output->start_output(desired_output_video_mode, pts_int);
 636         }
 637         output_card_index = card_index;
 638         output_jitter_history.clear();
 639 }
 640
 641 namespace {
 642
 643 int unwrap_timecode(uint16_t current_wrapped, int last)
 644 {
 645         uint16_t last_wrapped = last & 0xffff;
 646         if (current_wrapped > last_wrapped) {
 647                 return (last & ~0xffff) | current_wrapped;
 648         } else {
 649                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 650         }
 651 }
 652
 653 }  // namespace
 654
 655 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 656                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 657                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 658 {
 659         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 660         CaptureCard *card = &cards[card_index];
 661
 662         ++card->metric_input_received_frames;
 663         card->metric_input_has_signal_bool = video_format.has_signal;
 664         card->metric_input_is_connected_bool = video_format.is_connected;
 665         card->metric_input_interlaced_bool = video_format.interlaced;
 666         card->metric_input_width_pixels = video_format.width;
 667         card->metric_input_height_pixels = video_format.height;
 668         card->metric_input_frame_rate_nom = video_format.frame_rate_nom;
 669         card->metric_input_frame_rate_den = video_format.frame_rate_den;
 670         card->metric_input_sample_rate_hz = audio_format.sample_rate;
 671
 672         if (is_mode_scanning[card_index]) {
 673                 if (video_format.has_signal) {
 674                         // Found a stable signal, so stop scanning.
 675                         is_mode_scanning[card_index] = false;
 676                 } else {
 677                         static constexpr double switch_time_s = 0.1;  // Should be enough time for the signal to stabilize.
 678                         steady_clock::time_point now = steady_clock::now();
 679                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 680                         if (sec_since_last_switch > switch_time_s) {
 681                                 // It isn't this mode; try the next one.
 682                                 mode_scanlist_index[card_index]++;
 683                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 684                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 685                                 last_mode_scan_change[card_index] = now;
 686                         }
 687                 }
 688         }
 689
 690         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 691         assert(frame_length > 0);
 692
 693         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;
 694         if (num_samples > OUTPUT_FREQUENCY / 10) {
 695                 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",
 696                         card_index, int(audio_frame.len), int(audio_offset),
 697                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 698                 if (video_frame.owner) {
 699                         video_frame.owner->release_frame(video_frame);
 700                 }
 701                 if (audio_frame.owner) {
 702                         audio_frame.owner->release_frame(audio_frame);
 703                 }
 704                 return;
 705         }
 706
 707         int dropped_frames = 0;
 708         if (card->last_timecode != -1) {
 709                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 710         }
 711
 712         // Number of samples per frame if we need to insert silence.
 713         // (Could be nonintegral, but resampling will save us then.)
 714         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 715
 716         if (dropped_frames > MAX_FPS * 2) {
 717                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 718                         card_index, card->last_timecode, timecode);
 719                 audio_mixer.reset_resampler(device);
 720                 dropped_frames = 0;
 721                 ++card->metric_input_resets;
 722         } else if (dropped_frames > 0) {
 723                 // Insert silence as needed.
 724                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 725                         card_index, dropped_frames, timecode);
 726                 card->metric_input_dropped_frames_error += dropped_frames;
 727
 728                 bool success;
 729                 do {
 730                         success = audio_mixer.add_silence(device, silence_samples, dropped_frames, frame_length);
 731                 } while (!success);
 732         }
 733
 734         if (num_samples > 0) {
 735                 audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
 736         }
 737
 738         // Done with the audio, so release it.
 739         if (audio_frame.owner) {
 740                 audio_frame.owner->release_frame(audio_frame);
 741         }
 742
 743         card->last_timecode = timecode;
 744
 745         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 746
 747         size_t cbcr_width, cbcr_height, cbcr_offset, y_offset;
 748         size_t expected_length = video_format.stride * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom);
 749         if (userdata != nullptr && userdata->pixel_format == PixelFormat_8BitYCbCrPlanar) {
 750                 // The calculation above is wrong for planar Y'CbCr, so just override it.
 751                 assert(card->type == CardType::FFMPEG_INPUT);
 752                 assert(video_offset == 0);
 753                 expected_length = video_frame.len;
 754
 755                 userdata->ycbcr_format = (static_cast<FFmpegCapture *>(card->capture.get()))->get_current_frame_ycbcr_format();
 756                 cbcr_width = video_format.width / userdata->ycbcr_format.chroma_subsampling_x;
 757                 cbcr_height = video_format.height / userdata->ycbcr_format.chroma_subsampling_y;
 758                 cbcr_offset = video_format.width * video_format.height;
 759                 y_offset = 0;
 760         } else {
 761                 // All the other Y'CbCr formats are 4:2:2.
 762                 cbcr_width = video_format.width / 2;
 763                 cbcr_height = video_format.height;
 764                 cbcr_offset = video_offset / 2;
 765                 y_offset = video_frame.size / 2 + video_offset / 2;
 766         }
 767         if (video_frame.len - video_offset == 0 ||
 768             video_frame.len - video_offset != expected_length) {
 769                 if (video_frame.len != 0) {
 770                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 771                                 card_index, video_frame.len - video_offset, expected_length);
 772                 }
 773                 if (video_frame.owner) {
 774                         video_frame.owner->release_frame(video_frame);
 775                 }
 776
 777                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 778                 // so that pts can go up accordingly.
 779                 {
 780                         unique_lock<mutex> lock(card_mutex);
 781                         CaptureCard::NewFrame new_frame;
 782                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 783                         new_frame.length = frame_length;
 784                         new_frame.interlaced = false;
 785                         new_frame.dropped_frames = dropped_frames;
 786                         new_frame.received_timestamp = video_frame.received_timestamp;
 787                         card->new_frames.push_back(move(new_frame));
 788                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
 789                 }
 790                 card->new_frames_changed.notify_all();
 791                 return;
 792         }
 793
 794         unsigned num_fields = video_format.interlaced ? 2 : 1;
 795         steady_clock::time_point frame_upload_start;
 796         bool interlaced_stride = false;
 797         if (video_format.interlaced) {
 798                 // Send the two fields along as separate frames; the other side will need to add
 799                 // a deinterlacer to actually get this right.
 800                 assert(video_format.height % 2 == 0);
 801                 video_format.height /= 2;
 802                 cbcr_height /= 2;
 803                 assert(frame_length % 2 == 0);
 804                 frame_length /= 2;
 805                 num_fields = 2;
 806                 if (video_format.second_field_start == 1) {
 807                         interlaced_stride = true;
 808                 }
 809                 frame_upload_start = steady_clock::now();
 810         }
 811         userdata->last_interlaced = video_format.interlaced;
 812         userdata->last_has_signal = video_format.has_signal;
 813         userdata->last_is_connected = video_format.is_connected;
 814         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 815         userdata->last_frame_rate_den = video_format.frame_rate_den;
 816         RefCountedFrame frame(video_frame);
 817
 818         // Upload the textures.
 819         for (unsigned field = 0; field < num_fields; ++field) {
 820                 // Put the actual texture upload in a lambda that is executed in the main thread.
 821                 // It is entirely possible to do this in the same thread (and it might even be
 822                 // faster, depending on the GPU and driver), but it appears to be trickling
 823                 // driver bugs very easily.
 824                 //
 825                 // Note that this means we must hold on to the actual frame data in <userdata>
 826                 // until the upload command is run, but we hold on to <frame> much longer than that
 827                 // (in fact, all the way until we no longer use the texture in rendering).
 828                 auto upload_func = [this, field, video_format, y_offset, video_offset, cbcr_offset, cbcr_width, cbcr_height, interlaced_stride, userdata]() {
 829                         unsigned field_start_line;
 830                         if (field == 1) {
 831                                 field_start_line = video_format.second_field_start;
 832                         } else {
 833                                 field_start_line = video_format.extra_lines_top;
 834                         }
 835
 836                         // For anything not FRAME_FORMAT_YCBCR_10BIT, v210_width will be nonsensical but not used.
 837                         size_t v210_width = video_format.stride / sizeof(uint32_t);
 838                         ensure_texture_resolution(userdata, field, video_format.width, video_format.height, cbcr_width, cbcr_height, v210_width);
 839
 840                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, userdata->pbo);
 841                         check_error();
 842
 843                         switch (userdata->pixel_format) {
 844                         case PixelFormat_10BitYCbCr: {
 845                                 size_t field_start = video_offset + video_format.stride * field_start_line;
 846                                 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);
 847                                 v210_converter->convert(userdata->tex_v210[field], userdata->tex_444[field], video_format.width, video_format.height);
 848                                 break;
 849                         }
 850                         case PixelFormat_8BitYCbCr: {
 851                                 size_t field_y_start = y_offset + video_format.width * field_start_line;
 852                                 size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 853
 854                                 // Make up our own strides, since we are interleaving.
 855                                 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);
 856                                 upload_texture(userdata->tex_cbcr[field], cbcr_width, cbcr_height, cbcr_width * sizeof(uint16_t), interlaced_stride, GL_RG, GL_UNSIGNED_BYTE, field_cbcr_start);
 857                                 break;
 858                         }
 859                         case PixelFormat_8BitYCbCrPlanar: {
 860                                 assert(field_start_line == 0);  // We don't really support interlaced here.
 861                                 size_t field_y_start = y_offset;
 862                                 size_t field_cb_start = cbcr_offset;
 863                                 size_t field_cr_start = cbcr_offset + cbcr_width * cbcr_height;
 864
 865                                 // Make up our own strides, since we are interleaving.
 866                                 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);
 867                                 upload_texture(userdata->tex_cb[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cb_start);
 868                                 upload_texture(userdata->tex_cr[field], cbcr_width, cbcr_height, cbcr_width, interlaced_stride, GL_RED, GL_UNSIGNED_BYTE, field_cr_start);
 869                                 break;
 870                         }
 871                         case PixelFormat_8BitBGRA: {
 872                                 size_t field_start = video_offset + video_format.stride * field_start_line;
 873                                 upload_texture(userdata->tex_rgba[field], video_format.width, video_format.height, video_format.stride, interlaced_stride, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, field_start);
 874                                 // These could be asked to deliver mipmaps at any time.
 875                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_rgba[field]);
 876                                 check_error();
 877                                 glGenerateMipmap(GL_TEXTURE_2D);
 878                                 check_error();
 879                                 glBindTexture(GL_TEXTURE_2D, 0);
 880                                 check_error();
 881                                 break;
 882                         }
 883                         default:
 884                                 assert(false);
 885                         }
 886
 887                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 888                         check_error();
 889                 };
 890
 891                 if (field == 1) {
 892                         // Don't upload the second field as fast as we can; wait until
 893                         // the field time has approximately passed. (Otherwise, we could
 894                         // get timing jitter against the other sources, and possibly also
 895                         // against the video display, although the latter is not as critical.)
 896                         // This requires our system clock to be reasonably close to the
 897                         // video clock, but that's not an unreasonable assumption.
 898                         steady_clock::time_point second_field_start = frame_upload_start +
 899                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
 900                         this_thread::sleep_until(second_field_start);
 901                 }
 902
 903                 {
 904                         unique_lock<mutex> lock(card_mutex);
 905                         CaptureCard::NewFrame new_frame;
 906                         new_frame.frame = frame;
 907                         new_frame.length = frame_length;
 908                         new_frame.field = field;
 909                         new_frame.interlaced = video_format.interlaced;
 910                         new_frame.upload_func = upload_func;
 911                         new_frame.dropped_frames = dropped_frames;
 912                         new_frame.received_timestamp = video_frame.received_timestamp;  // Ignore the audio timestamp.
 913                         card->new_frames.push_back(move(new_frame));
 914                         card->jitter_history.frame_arrived(video_frame.received_timestamp, frame_length, dropped_frames);
 915                 }
 916                 card->new_frames_changed.notify_all();
 917         }
 918 }
 919
 920 void Mixer::bm_hotplug_add(libusb_device *dev)
 921 {
 922         lock_guard<mutex> lock(hotplug_mutex);
 923         hotplugged_cards.push_back(dev);
 924 }
 925
 926 void Mixer::bm_hotplug_remove(unsigned card_index)
 927 {
 928         cards[card_index].new_frames_changed.notify_all();
 929 }
 930
 931 void Mixer::thread_func()
 932 {
 933         pthread_setname_np(pthread_self(), "Mixer_OpenGL");
 934
 935         eglBindAPI(EGL_OPENGL_API);
 936         QOpenGLContext *context = create_context(mixer_surface);
 937         if (!make_current(context, mixer_surface)) {
 938                 printf("oops\n");
 939                 exit(1);
 940         }
 941
 942         // Start the actual capture. (We don't want to do it before we're actually ready
 943         // to process output frames.)
 944         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
 945                 if (int(card_index) != output_card_index) {
 946                         cards[card_index].capture->start_bm_capture();
 947                 }
 948         }
 949
 950         steady_clock::time_point start, now;
 951         start = steady_clock::now();
 952
 953         int stats_dropped_frames = 0;
 954
 955         while (!should_quit) {
 956                 if (desired_output_card_index != output_card_index) {
 957                         set_output_card_internal(desired_output_card_index);
 958                 }
 959                 if (output_card_index != -1 &&
 960                     desired_output_video_mode != output_video_mode) {
 961                         DeckLinkOutput *output = cards[output_card_index].output.get();
 962                         output->end_output();
 963                         desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
 964                         output->start_output(desired_output_video_mode, pts_int);
 965                 }
 966
 967                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
 968                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
 969
 970                 bool master_card_is_output;
 971                 unsigned master_card_index;
 972                 if (output_card_index != -1) {
 973                         master_card_is_output = true;
 974                         master_card_index = output_card_index;
 975                 } else {
 976                         master_card_is_output = false;
 977                         master_card_index = theme->map_signal(master_clock_channel);
 978                         assert(master_card_index < num_cards);
 979                 }
 980
 981                 OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
 982                 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);
 983                 stats_dropped_frames += output_frame_info.dropped_frames;
 984
 985                 handle_hotplugged_cards();
 986
 987                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
 988                         if (card_index == master_card_index || !has_new_frame[card_index]) {
 989                                 continue;
 990                         }
 991                         if (new_frames[card_index].frame->len == 0) {
 992                                 ++new_frames[card_index].dropped_frames;
 993                         }
 994                         if (new_frames[card_index].dropped_frames > 0) {
 995                                 printf("Card %u dropped %d frames before this\n",
 996                                         card_index, int(new_frames[card_index].dropped_frames));
 997                         }
 998                 }
 999
1000                 // If the first card is reporting a corrupted or otherwise dropped frame,
1001                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
1002                 if (!master_card_is_output && new_frames[master_card_index].frame->len == 0) {
1003                         ++stats_dropped_frames;
1004                         pts_int += new_frames[master_card_index].length;
1005                         continue;
1006                 }
1007
1008                 for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
1009                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
1010                                 continue;
1011
1012                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
1013                         assert(new_frame->frame != nullptr);
1014                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
1015                         check_error();
1016
1017                         // The new texture might need uploading before use.
1018                         if (new_frame->upload_func) {
1019                                 new_frame->upload_func();
1020                                 new_frame->upload_func = nullptr;
1021                         }
1022                 }
1023
1024                 int64_t frame_duration = output_frame_info.frame_duration;
1025                 render_one_frame(frame_duration);
1026                 ++frame_num;
1027                 pts_int += frame_duration;
1028
1029                 now = steady_clock::now();
1030                 double elapsed = duration<double>(now - start).count();
1031
1032                 metric_frames_output_total = frame_num;
1033                 metric_frames_output_dropped = stats_dropped_frames;
1034
1035                 if (frame_num % 100 == 0) {
1036                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
1037                                 frame_num, stats_dropped_frames, elapsed, frame_num / elapsed,
1038                                 1e3 * elapsed / frame_num);
1039                 //      chain->print_phase_timing();
1040
1041                         // Check our memory usage, to see if we are close to our mlockall()
1042                         // limit (if at all set).
1043                         rusage used;
1044                         if (getrusage(RUSAGE_SELF, &used) == -1) {
1045                                 perror("getrusage(RUSAGE_SELF)");
1046                                 assert(false);
1047                         }
1048
1049                         if (uses_mlock) {
1050                                 rlimit limit;
1051                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
1052                                         perror("getrlimit(RLIMIT_MEMLOCK)");
1053                                         assert(false);
1054                                 }
1055
1056                                 if (limit.rlim_cur == 0) {
1057                                         printf(", using %ld MB memory (locked)",
1058                                                 long(used.ru_maxrss / 1024));
1059                                 } else {
1060                                         printf(", using %ld / %ld MB lockable memory (%.1f%%)",
1061                                                 long(used.ru_maxrss / 1024),
1062                                                 long(limit.rlim_cur / 1048576),
1063                                                 float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
1064                                 }
1065                                 metrics_memory_locked_limit_bytes = limit.rlim_cur;
1066                         } else {
1067                                 printf(", using %ld MB memory (not locked)",
1068                                         long(used.ru_maxrss / 1024));
1069                                 metrics_memory_locked_limit_bytes = 0.0 / 0.0;
1070                         }
1071
1072                         printf("\n");
1073
1074                         metrics_memory_used_bytes = used.ru_maxrss * 1024;
1075                 }
1076
1077
1078                 if (should_cut.exchange(false)) {  // Test and clear.
1079                         video_encoder->do_cut(frame_num);
1080                 }
1081
1082 #if 0
1083                 // Reset every 100 frames, so that local variations in frame times
1084                 // (especially for the first few frames, when the shaders are
1085                 // compiled etc.) don't make it hard to measure for the entire
1086                 // remaining duration of the program.
1087                 if (frame == 10000) {
1088                         frame = 0;
1089                         start = now;
1090                 }
1091 #endif
1092                 check_error();
1093         }
1094
1095         resource_pool->clean_context();
1096 }
1097
1098 bool Mixer::input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const
1099 {
1100         if (output_card_index != -1) {
1101                 // The output card (ie., cards[output_card_index].output) is the master clock,
1102                 // so no input card (ie., cards[card_index].capture) is.
1103                 return false;
1104         }
1105         return (card_index == master_card_index);
1106 }
1107
1108 void Mixer::trim_queue(CaptureCard *card, size_t safe_queue_length)
1109 {
1110         // Count the number of frames in the queue, including any frames
1111         // we dropped. It's hard to know exactly how we should deal with
1112         // dropped (corrupted) input frames; they don't help our goal of
1113         // avoiding starvation, but they still add to the problem of latency.
1114         // Since dropped frames is going to mean a bump in the signal anyway,
1115         // we err on the side of having more stable latency instead.
1116         unsigned queue_length = 0;
1117         for (const CaptureCard::NewFrame &frame : card->new_frames) {
1118                 queue_length += frame.dropped_frames + 1;
1119         }
1120
1121         // If needed, drop frames until the queue is below the safe limit.
1122         // We prefer to drop from the head, because all else being equal,
1123         // we'd like more recent frames (less latency).
1124         unsigned dropped_frames = 0;
1125         while (queue_length > safe_queue_length) {
1126                 assert(!card->new_frames.empty());
1127                 assert(queue_length > card->new_frames.front().dropped_frames);
1128                 queue_length -= card->new_frames.front().dropped_frames;
1129
1130                 if (queue_length <= safe_queue_length) {
1131                         // No need to drop anything.
1132                         break;
1133                 }
1134
1135                 card->new_frames.pop_front();
1136                 card->new_frames_changed.notify_all();
1137                 --queue_length;
1138                 ++dropped_frames;
1139         }
1140
1141         card->metric_input_dropped_frames_jitter += dropped_frames;
1142         card->metric_input_queue_length_frames = queue_length;
1143
1144 #if 0
1145         if (dropped_frames > 0) {
1146                 fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
1147                         card_index, dropped_frames);
1148         }
1149 #endif
1150 }
1151
1152
1153 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])
1154 {
1155         OutputFrameInfo output_frame_info;
1156 start:
1157         unique_lock<mutex> lock(card_mutex, defer_lock);
1158         if (master_card_is_output) {
1159                 // Clocked to the output, so wait for it to be ready for the next frame.
1160                 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);
1161                 lock.lock();
1162         } else {
1163                 // Wait for the master card to have a new frame.
1164                 // TODO: Add a timeout.
1165                 output_frame_info.is_preroll = false;
1166                 lock.lock();
1167                 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(); });
1168         }
1169
1170         if (master_card_is_output) {
1171                 handle_hotplugged_cards();
1172         } else if (cards[master_card_index].new_frames.empty()) {
1173                 // We were woken up, but not due to a new frame. Deal with it
1174                 // and then restart.
1175                 assert(cards[master_card_index].capture->get_disconnected());
1176                 handle_hotplugged_cards();
1177                 lock.unlock();
1178                 goto start;
1179         }
1180
1181         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
1182                 CaptureCard *card = &cards[card_index];
1183                 if (card->new_frames.empty()) {  // Starvation.
1184                         ++card->metric_input_duped_frames;
1185                 } else {
1186                         new_frames[card_index] = move(card->new_frames.front());
1187                         has_new_frame[card_index] = true;
1188                         card->new_frames.pop_front();
1189                         card->new_frames_changed.notify_all();
1190                 }
1191         }
1192
1193         if (!master_card_is_output) {
1194                 output_frame_info.frame_timestamp = new_frames[master_card_index].received_timestamp;
1195                 output_frame_info.dropped_frames = new_frames[master_card_index].dropped_frames;
1196                 output_frame_info.frame_duration = new_frames[master_card_index].length;
1197         }
1198
1199         if (!output_frame_info.is_preroll) {
1200                 output_jitter_history.frame_arrived(output_frame_info.frame_timestamp, output_frame_info.frame_duration, output_frame_info.dropped_frames);
1201         }
1202
1203         for (unsigned card_index = 0; card_index < num_cards + num_video_inputs; ++card_index) {
1204                 CaptureCard *card = &cards[card_index];
1205                 if (has_new_frame[card_index] &&
1206                     !input_card_is_master_clock(card_index, master_card_index) &&
1207                     !output_frame_info.is_preroll) {
1208                         card->queue_length_policy.update_policy(
1209                                 output_frame_info.frame_timestamp,
1210                                 card->jitter_history.get_expected_next_frame(),
1211                                 new_frames[master_card_index].length,
1212                                 output_frame_info.frame_duration,
1213                                 card->jitter_history.estimate_max_jitter(),
1214                                 output_jitter_history.estimate_max_jitter());
1215                         trim_queue(card, min<int>(global_flags.max_input_queue_frames,
1216                                                   card->queue_length_policy.get_safe_queue_length()));
1217                 }
1218         }
1219
1220         // This might get off by a fractional sample when changing master card
1221         // between ones with different frame rates, but that's fine.
1222         int num_samples_times_timebase = OUTPUT_FREQUENCY * output_frame_info.frame_duration + fractional_samples;
1223         output_frame_info.num_samples = num_samples_times_timebase / TIMEBASE;
1224         fractional_samples = num_samples_times_timebase % TIMEBASE;
1225         assert(output_frame_info.num_samples >= 0);
1226
1227         return output_frame_info;
1228 }
1229
1230 void Mixer::handle_hotplugged_cards()
1231 {
1232         // Check for cards that have been disconnected since last frame.
1233         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1234                 CaptureCard *card = &cards[card_index];
1235                 if (card->capture->get_disconnected()) {
1236                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
1237                         FakeCapture *capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
1238                         configure_card(card_index, capture, CardType::FAKE_CAPTURE, /*output=*/nullptr);
1239                         card->queue_length_policy.reset(card_index);
1240                         card->capture->start_bm_capture();
1241                 }
1242         }
1243
1244         // Check for cards that have been connected since last frame.
1245         vector<libusb_device *> hotplugged_cards_copy;
1246         {
1247                 lock_guard<mutex> lock(hotplug_mutex);
1248                 swap(hotplugged_cards, hotplugged_cards_copy);
1249         }
1250         for (libusb_device *new_dev : hotplugged_cards_copy) {
1251                 // Look for a fake capture card where we can stick this in.
1252                 int free_card_index = -1;
1253                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1254                         if (cards[card_index].is_fake_capture) {
1255                                 free_card_index = card_index;
1256                                 break;
1257                         }
1258                 }
1259
1260                 if (free_card_index == -1) {
1261                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
1262                         libusb_unref_device(new_dev);
1263                 } else {
1264                         // BMUSBCapture takes ownership.
1265                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
1266                         CaptureCard *card = &cards[free_card_index];
1267                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
1268                         configure_card(free_card_index, capture, CardType::LIVE_CARD, /*output=*/nullptr);
1269                         card->queue_length_policy.reset(free_card_index);
1270                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
1271                         capture->start_bm_capture();
1272                 }
1273         }
1274 }
1275
1276
1277 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)
1278 {
1279         // Resample the audio as needed, including from previously dropped frames.
1280         assert(num_cards > 0);
1281         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
1282                 const bool dropped_frame = (frame_num != dropped_frames);
1283                 {
1284                         // Signal to the audio thread to process this frame.
1285                         // Note that if the frame is a dropped frame, we signal that
1286                         // we don't want to use this frame as base for adjusting
1287                         // the resampler rate. The reason for this is that the timing
1288                         // of these frames is often way too late; they typically don't
1289                         // “arrive” before we synthesize them. Thus, we could end up
1290                         // in a situation where we have inserted e.g. five audio frames
1291                         // into the queue before we then start pulling five of them
1292                         // back out. This makes ResamplingQueue overestimate the delay,
1293                         // causing undue resampler changes. (We _do_ use the last,
1294                         // non-dropped frame; perhaps we should just discard that as well,
1295                         // since dropped frames are expected to be rare, and it might be
1296                         // better to just wait until we have a slightly more normal situation).
1297                         unique_lock<mutex> lock(audio_mutex);
1298                         bool adjust_rate = !dropped_frame && !is_preroll;
1299                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
1300                         audio_task_queue_changed.notify_one();
1301                 }
1302                 if (dropped_frame) {
1303                         // For dropped frames, increase the pts. Note that if the format changed
1304                         // in the meantime, we have no way of detecting that; we just have to
1305                         // assume the frame length is always the same.
1306                         pts_int += length_per_frame;
1307                 }
1308         }
1309 }
1310
1311 void Mixer::render_one_frame(int64_t duration)
1312 {
1313         // Determine the time code for this frame before we start rendering.
1314         string timecode_text = timecode_renderer->get_timecode_text(double(pts_int) / TIMEBASE, frame_num);
1315         if (display_timecode_on_stdout) {
1316                 printf("Timecode: '%s'\n", timecode_text.c_str());
1317         }
1318
1319         // Update Y'CbCr settings for all cards.
1320         {
1321                 unique_lock<mutex> lock(card_mutex);
1322                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
1323                         YCbCrInterpretation *interpretation = &ycbcr_interpretation[card_index];
1324                         input_state.ycbcr_coefficients_auto[card_index] = interpretation->ycbcr_coefficients_auto;
1325                         input_state.ycbcr_coefficients[card_index] = interpretation->ycbcr_coefficients;
1326                         input_state.full_range[card_index] = interpretation->full_range;
1327                 }
1328         }
1329
1330         // Get the main chain from the theme, and set its state immediately.
1331         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), global_flags.width, global_flags.height, input_state);
1332         EffectChain *chain = theme_main_chain.chain;
1333         theme_main_chain.setup_chain();
1334         //theme_main_chain.chain->enable_phase_timing(true);
1335
1336         // The theme can't (or at least shouldn't!) call connect_signal() on
1337         // each FFmpeg input, so we'll do it here.
1338         for (const pair<LiveInputWrapper *, FFmpegCapture *> &conn : theme->get_signal_connections()) {
1339                 conn.first->connect_signal_raw(conn.second->get_card_index(), input_state);
1340         }
1341
1342         // If HDMI/SDI output is active and the user has requested auto mode,
1343         // its mode overrides the existing Y'CbCr setting for the chain.
1344         YCbCrLumaCoefficients ycbcr_output_coefficients;
1345         if (global_flags.ycbcr_auto_coefficients && output_card_index != -1) {
1346                 ycbcr_output_coefficients = cards[output_card_index].output->preferred_ycbcr_coefficients();
1347         } else {
1348                 ycbcr_output_coefficients = global_flags.ycbcr_rec709_coefficients ? YCBCR_REC_709 : YCBCR_REC_601;
1349         }
1350
1351         // TODO: Reduce the duplication against theme.cpp.
1352         YCbCrFormat output_ycbcr_format;
1353         output_ycbcr_format.chroma_subsampling_x = 1;
1354         output_ycbcr_format.chroma_subsampling_y = 1;
1355         output_ycbcr_format.luma_coefficients = ycbcr_output_coefficients;
1356         output_ycbcr_format.full_range = false;
1357         output_ycbcr_format.num_levels = 1 << global_flags.x264_bit_depth;
1358         chain->change_ycbcr_output_format(output_ycbcr_format);
1359
1360         // Render main chain. If we're using zerocopy Quick Sync encoding
1361         // (the default case), we take an extra copy of the created outputs,
1362         // so that we can display it back to the screen later (it's less memory
1363         // bandwidth than writing and reading back an RGBA texture, even at 16-bit).
1364         // Ideally, we'd like to avoid taking copies and just use the main textures
1365         // for display as well, but they're just views into VA-API memory and must be
1366         // unmapped during encoding, so we can't use them for display, unfortunately.
1367         GLuint y_tex, cbcr_full_tex, cbcr_tex;
1368         GLuint y_copy_tex, cbcr_copy_tex = 0;
1369         GLuint y_display_tex, cbcr_display_tex;
1370         GLenum y_type = (global_flags.x264_bit_depth > 8) ? GL_R16 : GL_R8;
1371         GLenum cbcr_type = (global_flags.x264_bit_depth > 8) ? GL_RG16 : GL_RG8;
1372         const bool is_zerocopy = video_encoder->is_zerocopy();
1373         if (is_zerocopy) {
1374                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1375                 y_copy_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1376                 cbcr_copy_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1377
1378                 y_display_tex = y_copy_tex;
1379                 cbcr_display_tex = cbcr_copy_tex;
1380
1381                 // y_tex and cbcr_tex will be given by VideoEncoder.
1382         } else {
1383                 cbcr_full_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width, global_flags.height);
1384                 y_tex = resource_pool->create_2d_texture(y_type, global_flags.width, global_flags.height);
1385                 cbcr_tex = resource_pool->create_2d_texture(cbcr_type, global_flags.width / 2, global_flags.height / 2);
1386
1387                 y_display_tex = y_tex;
1388                 cbcr_display_tex = cbcr_tex;
1389         }
1390
1391         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1392         bool got_frame = video_encoder->begin_frame(pts_int + av_delay, duration, ycbcr_output_coefficients, theme_main_chain.input_frames, &y_tex, &cbcr_tex);
1393         assert(got_frame);
1394
1395         GLuint fbo;
1396         if (is_zerocopy) {
1397                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, y_copy_tex);
1398         } else {
1399                 fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex);
1400         }
1401         check_error();
1402         chain->render_to_fbo(fbo, global_flags.width, global_flags.height);
1403
1404         if (display_timecode_in_stream) {
1405                 // Render the timecode on top.
1406                 timecode_renderer->render_timecode(fbo, timecode_text);
1407         }
1408
1409         resource_pool->release_fbo(fbo);
1410
1411         if (is_zerocopy) {
1412                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex, cbcr_copy_tex);
1413         } else {
1414                 chroma_subsampler->subsample_chroma(cbcr_full_tex, global_flags.width, global_flags.height, cbcr_tex);
1415         }
1416         if (output_card_index != -1) {
1417                 cards[output_card_index].output->send_frame(y_tex, cbcr_full_tex, ycbcr_output_coefficients, theme_main_chain.input_frames, pts_int, duration);
1418         }
1419         resource_pool->release_2d_texture(cbcr_full_tex);
1420
1421         // Set the right state for the Y' and CbCr textures we use for display.
1422         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1423         glBindTexture(GL_TEXTURE_2D, y_display_tex);
1424         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1425         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1426         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1427
1428         glBindTexture(GL_TEXTURE_2D, cbcr_display_tex);
1429         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1430         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
1431         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
1432
1433         RefCountedGLsync fence = video_encoder->end_frame();
1434
1435         // The live frame pieces the Y'CbCr texture copies back into RGB and displays them.
1436         // It owns y_display_tex and cbcr_display_tex now (whichever textures they are).
1437         DisplayFrame live_frame;
1438         live_frame.chain = display_chain.get();
1439         live_frame.setup_chain = [this, y_display_tex, cbcr_display_tex]{
1440                 display_input->set_texture_num(0, y_display_tex);
1441                 display_input->set_texture_num(1, cbcr_display_tex);
1442         };
1443         live_frame.ready_fence = fence;
1444         live_frame.input_frames = {};
1445         live_frame.temp_textures = { y_display_tex, cbcr_display_tex };
1446         output_channel[OUTPUT_LIVE].output_frame(live_frame);
1447
1448         // Set up preview and any additional channels.
1449         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
1450                 DisplayFrame display_frame;
1451                 Theme::Chain chain = theme->get_chain(i, pts(), global_flags.width, global_flags.height, input_state);  // FIXME: dimensions
1452                 display_frame.chain = chain.chain;
1453                 display_frame.setup_chain = chain.setup_chain;
1454                 display_frame.ready_fence = fence;
1455                 display_frame.input_frames = chain.input_frames;
1456                 display_frame.temp_textures = {};
1457                 output_channel[i].output_frame(display_frame);
1458         }
1459 }
1460
1461 void Mixer::audio_thread_func()
1462 {
1463         pthread_setname_np(pthread_self(), "Mixer_Audio");
1464
1465         while (!should_quit) {
1466                 AudioTask task;
1467
1468                 {
1469                         unique_lock<mutex> lock(audio_mutex);
1470                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
1471                         if (should_quit) {
1472                                 return;
1473                         }
1474                         task = audio_task_queue.front();
1475                         audio_task_queue.pop();
1476                 }
1477
1478                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
1479                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
1480                 vector<float> samples_out = audio_mixer.get_output(
1481                         task.frame_timestamp,
1482                         task.num_samples,
1483                         rate_adjustment_policy);
1484
1485                 // Send the samples to the sound card, then add them to the output.
1486                 if (alsa) {
1487                         alsa->write(samples_out);
1488                 }
1489                 if (output_card_index != -1) {
1490                         const int64_t av_delay = lrint(global_flags.audio_queue_length_ms * 0.001 * TIMEBASE);  // Corresponds to the delay in ResamplingQueue.
1491                         cards[output_card_index].output->send_audio(task.pts_int + av_delay, samples_out);
1492                 }
1493                 video_encoder->add_audio(task.pts_int, move(samples_out));
1494         }
1495 }
1496
1497 void Mixer::release_display_frame(DisplayFrame *frame)
1498 {
1499         for (GLuint texnum : frame->temp_textures) {
1500                 resource_pool->release_2d_texture(texnum);
1501         }
1502         frame->temp_textures.clear();
1503         frame->ready_fence.reset();
1504         frame->input_frames.clear();
1505 }
1506
1507 void Mixer::start()
1508 {
1509         mixer_thread = thread(&Mixer::thread_func, this);
1510         audio_thread = thread(&Mixer::audio_thread_func, this);
1511 }
1512
1513 void Mixer::quit()
1514 {
1515         should_quit = true;
1516         audio_task_queue_changed.notify_one();
1517         mixer_thread.join();
1518         audio_thread.join();
1519 }
1520
1521 void Mixer::transition_clicked(int transition_num)
1522 {
1523         theme->transition_clicked(transition_num, pts());
1524 }
1525
1526 void Mixer::channel_clicked(int preview_num)
1527 {
1528         theme->channel_clicked(preview_num);
1529 }
1530
1531 YCbCrInterpretation Mixer::get_input_ycbcr_interpretation(unsigned card_index) const
1532 {
1533         unique_lock<mutex> lock(card_mutex);
1534         return ycbcr_interpretation[card_index];
1535 }
1536
1537 void Mixer::set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation)
1538 {
1539         unique_lock<mutex> lock(card_mutex);
1540         ycbcr_interpretation[card_index] = interpretation;
1541 }
1542
1543 void Mixer::start_mode_scanning(unsigned card_index)
1544 {
1545         assert(card_index < num_cards);
1546         if (is_mode_scanning[card_index]) {
1547                 return;
1548         }
1549         is_mode_scanning[card_index] = true;
1550         mode_scanlist[card_index].clear();
1551         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1552                 mode_scanlist[card_index].push_back(mode.first);
1553         }
1554         assert(!mode_scanlist[card_index].empty());
1555         mode_scanlist_index[card_index] = 0;
1556         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1557         last_mode_scan_change[card_index] = steady_clock::now();
1558 }
1559
1560 map<uint32_t, VideoMode> Mixer::get_available_output_video_modes() const
1561 {
1562         assert(desired_output_card_index != -1);
1563         unique_lock<mutex> lock(card_mutex);
1564         return cards[desired_output_card_index].output->get_available_video_modes();
1565 }
1566
1567 Mixer::OutputChannel::~OutputChannel()
1568 {
1569         if (has_current_frame) {
1570                 parent->release_display_frame(&current_frame);
1571         }
1572         if (has_ready_frame) {
1573                 parent->release_display_frame(&ready_frame);
1574         }
1575 }
1576
1577 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1578 {
1579         // Store this frame for display. Remove the ready frame if any
1580         // (it was seemingly never used).
1581         {
1582                 unique_lock<mutex> lock(frame_mutex);
1583                 if (has_ready_frame) {
1584                         parent->release_display_frame(&ready_frame);
1585                 }
1586                 ready_frame = frame;
1587                 has_ready_frame = true;
1588
1589                 // Call the callbacks under the mutex (they should be short),
1590                 // so that we don't race against a callback removal.
1591                 for (const auto &key_and_callback : new_frame_ready_callbacks) {
1592                         key_and_callback.second();
1593                 }
1594         }
1595
1596         // Reduce the number of callbacks by filtering duplicates. The reason
1597         // why we bother doing this is that Qt seemingly can get into a state
1598         // where its builds up an essentially unbounded queue of signals,
1599         // consuming more and more memory, and there's no good way of collapsing
1600         // user-defined signals or limiting the length of the queue.
1601         if (transition_names_updated_callback) {
1602                 vector<string> transition_names = global_mixer->get_transition_names();
1603                 bool changed = false;
1604                 if (transition_names.size() != last_transition_names.size()) {
1605                         changed = true;
1606                 } else {
1607                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1608                                 if (transition_names[i] != last_transition_names[i]) {
1609                                         changed = true;
1610                                         break;
1611                                 }
1612                         }
1613                 }
1614                 if (changed) {
1615                         transition_names_updated_callback(transition_names);
1616                         last_transition_names = transition_names;
1617                 }
1618         }
1619         if (name_updated_callback) {
1620                 string name = global_mixer->get_channel_name(channel);
1621                 if (name != last_name) {
1622                         name_updated_callback(name);
1623                         last_name = name;
1624                 }
1625         }
1626         if (color_updated_callback) {
1627                 string color = global_mixer->get_channel_color(channel);
1628                 if (color != last_color) {
1629                         color_updated_callback(color);
1630                         last_color = color;
1631                 }
1632         }
1633 }
1634
1635 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1636 {
1637         unique_lock<mutex> lock(frame_mutex);
1638         if (!has_current_frame && !has_ready_frame) {
1639                 return false;
1640         }
1641
1642         if (has_current_frame && has_ready_frame) {
1643                 // We have a new ready frame. Toss the current one.
1644                 parent->release_display_frame(&current_frame);
1645                 has_current_frame = false;
1646         }
1647         if (has_ready_frame) {
1648                 assert(!has_current_frame);
1649                 current_frame = ready_frame;
1650                 ready_frame.ready_fence.reset();  // Drop the refcount.
1651                 ready_frame.input_frames.clear();  // Drop the refcounts.
1652                 has_current_frame = true;
1653                 has_ready_frame = false;
1654         }
1655
1656         *frame = current_frame;
1657         return true;
1658 }
1659
1660 void Mixer::OutputChannel::add_frame_ready_callback(void *key, Mixer::new_frame_ready_callback_t callback)
1661 {
1662         unique_lock<mutex> lock(frame_mutex);
1663         new_frame_ready_callbacks[key] = callback;
1664 }
1665
1666 void Mixer::OutputChannel::remove_frame_ready_callback(void *key)
1667 {
1668         unique_lock<mutex> lock(frame_mutex);
1669         new_frame_ready_callbacks.erase(key);
1670 }
1671
1672 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1673 {
1674         transition_names_updated_callback = callback;
1675 }
1676
1677 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1678 {
1679         name_updated_callback = callback;
1680 }
1681
1682 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1683 {
1684         color_updated_callback = callback;
1685 }
1686
1687 mutex RefCountedGLsync::fence_lock;