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

   1 #define WIDTH 1280
   2 #define HEIGHT 720
   3
   4 #undef Success
   5
   6 #include "mixer.h"
   7
   8 #include <assert.h>
   9 #include <effect.h>
  10 #include <effect_chain.h>
  11 #include <effect_util.h>
  12 #include <epoxy/egl.h>
  13 #include <features.h>
  14 #include <image_format.h>
  15 #include <init.h>
  16 #include <overlay_effect.h>
  17 #include <padding_effect.h>
  18 #include <resample_effect.h>
  19 #include <resource_pool.h>
  20 #include <saturation_effect.h>
  21 #include <stdint.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <sys/time.h>
  25 #include <time.h>
  26 #include <util.h>
  27 #include <white_balance_effect.h>
  28 #include <ycbcr.h>
  29 #include <ycbcr_input.h>
  30 #include <cmath>
  31 #include <condition_variable>
  32 #include <cstddef>
  33 #include <memory>
  34 #include <mutex>
  35 #include <string>
  36 #include <thread>
  37 #include <vector>
  38
  39 #include "bmusb/bmusb.h"
  40 #include "context.h"
  41 #include "h264encode.h"
  42 #include "pbo_frame_allocator.h"
  43 #include "ref_counted_gl_sync.h"
  44 #include "timebase.h"
  45
  46 class QOpenGLContext;
  47
  48 using namespace movit;
  49 using namespace std;
  50 using namespace std::placeholders;
  51
  52 Mixer *global_mixer = nullptr;
  53
  54 namespace {
  55
  56 void convert_fixed24_to_fp32(float *dst, size_t out_channels, const uint8_t *src, size_t in_channels, size_t num_samples)
  57 {
  58         for (size_t i = 0; i < num_samples; ++i) {
  59                 for (size_t j = 0; j < out_channels; ++j) {
  60                         uint32_t s1 = *src++;
  61                         uint32_t s2 = *src++;
  62                         uint32_t s3 = *src++;
  63                         uint32_t s = s1 | (s1 << 8) | (s2 << 16) | (s3 << 24);
  64                         dst[i * out_channels + j] = int(s) * (1.0f / 4294967296.0f);
  65                 }
  66                 src += 3 * (in_channels - out_channels);
  67         }
  68 }
  69
  70 }  // namespace
  71
  72 Mixer::Mixer(const QSurfaceFormat &format)
  73         : mixer_surface(create_surface(format)),
  74           h264_encoder_surface(create_surface(format))
  75 {
  76         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
  77         check_error();
  78
  79         resource_pool.reset(new ResourcePool);
  80         theme.reset(new Theme("theme.lua", resource_pool.get()));
  81         output_channel[OUTPUT_LIVE].parent = this;
  82         output_channel[OUTPUT_PREVIEW].parent = this;
  83         output_channel[OUTPUT_INPUT0].parent = this;
  84         output_channel[OUTPUT_INPUT1].parent = this;
  85
  86         ImageFormat inout_format;
  87         inout_format.color_space = COLORSPACE_sRGB;
  88         inout_format.gamma_curve = GAMMA_sRGB;
  89
  90         // Display chain; shows the live output produced by the main chain (its RGBA version).
  91         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
  92         check_error();
  93         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
  94         display_chain->add_input(display_input);
  95         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
  96         display_chain->set_dither_bits(0);  // Don't bother.
  97         display_chain->finalize();
  98
  99         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, "test.mp4"));
 100
 101         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 102                 printf("Configuring card %d...\n", card_index);
 103                 CaptureCard *card = &cards[card_index];
 104                 card->usb = new BMUSBCapture(0x1edb, card_index == 0 ? 0xbd3b : 0xbd4f);
 105                 card->usb->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 106                 card->frame_allocator.reset(new PBOFrameAllocator(WIDTH * (HEIGHT+30) * 2 + 44, WIDTH, HEIGHT));
 107                 card->usb->set_video_frame_allocator(card->frame_allocator.get());
 108                 card->surface = create_surface(format);
 109                 card->usb->set_dequeue_thread_callbacks(
 110                         [card]{
 111                                 eglBindAPI(EGL_OPENGL_API);
 112                                 card->context = create_context();
 113                                 if (!make_current(card->context, card->surface)) {
 114                                         printf("failed to create bmusb context\n");
 115                                         exit(1);
 116                                 }
 117                                 printf("inited!\n");
 118                         },
 119                         [this]{
 120                                 resource_pool->clean_context();
 121                         });
 122                 card->resampler.reset(new Resampler(48000.0, 48000.0, 2));
 123                 card->usb->configure_card();
 124         }
 125
 126         BMUSBCapture::start_bm_thread();
 127
 128         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 129                 cards[card_index].usb->start_bm_capture();
 130         }
 131
 132         //chain->enable_phase_timing(true);
 133
 134         // Set up stuff for NV12 conversion.
 135
 136         // Cb/Cr shader.
 137         string cbcr_vert_shader = read_file("vs-cbcr.130.vert");
 138         string cbcr_frag_shader =
 139                 "#version 130 \n"
 140                 "in vec2 tc0; \n"
 141                 "uniform sampler2D cbcr_tex; \n"
 142                 "void main() { \n"
 143                 "    gl_FragColor = texture2D(cbcr_tex, tc0); \n"
 144                 "} \n";
 145         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader);
 146 }
 147
 148 Mixer::~Mixer()
 149 {
 150         resource_pool->release_glsl_program(cbcr_program_num);
 151         BMUSBCapture::stop_bm_thread();
 152
 153         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 154                 {
 155                         unique_lock<mutex> lock(bmusb_mutex);
 156                         cards[card_index].should_quit = true;  // Unblock thread.
 157                         cards[card_index].new_data_ready_changed.notify_all();
 158                 }
 159                 cards[card_index].usb->stop_dequeue_thread();
 160         }
 161 }
 162
 163 namespace {
 164
 165 int unwrap_timecode(uint16_t current_wrapped, int last)
 166 {
 167         uint16_t last_wrapped = last & 0xffff;
 168         if (current_wrapped > last_wrapped) {
 169                 return (last & ~0xffff) | current_wrapped;
 170         } else {
 171                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 172         }
 173 }
 174
 175 }  // namespace
 176
 177 void Mixer::bm_frame(int card_index, uint16_t timecode,
 178                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 179                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
 180 {
 181         CaptureCard *card = &cards[card_index];
 182
 183         if (audio_frame.len - audio_offset > 30000) {
 184                 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",
 185                         card_index, int(audio_frame.len), int(audio_offset),
 186                         timecode, int(video_frame.len), int(video_offset), video_format);
 187                 if (video_frame.owner) {
 188                         video_frame.owner->release_frame(video_frame);
 189                 }
 190                 if (audio_frame.owner) {
 191                         audio_frame.owner->release_frame(audio_frame);
 192                 }
 193                 return;
 194         }
 195
 196         // Convert the audio to stereo fp32 and add it.
 197         size_t num_samples = (audio_frame.len - audio_offset) / 8 / 3;
 198         vector<float> audio;
 199         audio.resize(num_samples * 2);
 200         convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
 201
 202         int unwrapped_timecode = timecode;
 203         int dropped_frames = 0;
 204         if (card->last_timecode != -1) {
 205                 unwrapped_timecode = unwrap_timecode(unwrapped_timecode, card->last_timecode);
 206                 dropped_frames = unwrapped_timecode - card->last_timecode - 1;
 207         }
 208         card->last_timecode = unwrapped_timecode;
 209
 210         // Add the audio.
 211         {
 212                 unique_lock<mutex> lock(card->audio_mutex);
 213
 214                 int unwrapped_timecode = timecode;
 215                 if (dropped_frames > 60 * 2) {
 216                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around), resetting resampler\n",
 217                                 card_index);
 218                         card->resampler.reset(new Resampler(48000.0, 48000.0, 2));
 219                 } else if (dropped_frames > 0) {
 220                         // Insert silence as needed.
 221                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 222                                 card_index, dropped_frames, timecode);
 223                         vector<float> silence;
 224                         silence.resize((48000 / 60) * 2);
 225                         for (int i = 0; i < dropped_frames; ++i) {
 226                                 card->resampler->add_input_samples((unwrapped_timecode - dropped_frames + i) / 60.0, silence.data(), (48000 / 60));
 227                         }
 228                 }
 229                 card->resampler->add_input_samples(unwrapped_timecode / 60.0, audio.data(), num_samples);
 230         }
 231
 232         // Done with the audio, so release it.
 233         if (audio_frame.owner) {
 234                 audio_frame.owner->release_frame(audio_frame);
 235         }
 236
 237         {
 238                 // Wait until the previous frame was consumed.
 239                 unique_lock<mutex> lock(bmusb_mutex);
 240                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
 241                 if (card->should_quit) return;
 242         }
 243
 244         if (video_frame.len - video_offset != WIDTH * (HEIGHT+30) * 2) {
 245                 if (video_frame.len != 0) {
 246                         printf("Card %d: Dropping video frame with wrong length (%ld)\n",
 247                                 card_index, video_frame.len - video_offset);
 248                 }
 249                 if (video_frame.owner) {
 250                         video_frame.owner->release_frame(video_frame);
 251                 }
 252
 253                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 254                 // so that pts can go up accordingly.
 255                 {
 256                         unique_lock<mutex> lock(bmusb_mutex);
 257                         card->new_data_ready = true;
 258                         card->new_frame = RefCountedFrame(FrameAllocator::Frame());
 259                         card->new_data_ready_fence = nullptr;
 260                         card->dropped_frames = dropped_frames;
 261                         card->new_data_ready_changed.notify_all();
 262                 }
 263                 return;
 264         }
 265
 266         const PBOFrameAllocator::Userdata *userdata = (const PBOFrameAllocator::Userdata *)video_frame.userdata;
 267         GLuint pbo = userdata->pbo;
 268         check_error();
 269         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
 270         check_error();
 271         glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, video_frame.size);
 272         check_error();
 273         //glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 274         //check_error();
 275
 276         // Upload the textures.
 277         glBindTexture(GL_TEXTURE_2D, userdata->tex_y);
 278         check_error();
 279         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, WIDTH, HEIGHT, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET((WIDTH * (HEIGHT+30) * 2 + 44) / 2 + WIDTH * 25 + 22));
 280         check_error();
 281         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr);
 282         check_error();
 283         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, WIDTH/2, HEIGHT, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(WIDTH * 25 + 22));
 284         check_error();
 285         glBindTexture(GL_TEXTURE_2D, 0);
 286         check_error();
 287         GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 288         check_error();
 289         assert(fence != nullptr);
 290
 291         {
 292                 unique_lock<mutex> lock(bmusb_mutex);
 293                 card->new_data_ready = true;
 294                 card->new_frame = RefCountedFrame(video_frame);
 295                 card->new_data_ready_fence = fence;
 296                 card->dropped_frames = dropped_frames;
 297                 card->new_data_ready_changed.notify_all();
 298         }
 299 }
 300
 301 void Mixer::thread_func()
 302 {
 303         eglBindAPI(EGL_OPENGL_API);
 304         QOpenGLContext *context = create_context();
 305         if (!make_current(context, mixer_surface)) {
 306                 printf("oops\n");
 307                 exit(1);
 308         }
 309
 310         struct timespec start, now;
 311         clock_gettime(CLOCK_MONOTONIC, &start);
 312
 313         int frame = 0;
 314         int dropped_frames = 0;
 315
 316         while (!should_quit) {
 317                 CaptureCard card_copy[NUM_CARDS];
 318
 319                 {
 320                         unique_lock<mutex> lock(bmusb_mutex);
 321
 322                         // The first card is the master timer, so wait for it to have a new frame.
 323                         // TODO: Make configurable, and with a timeout.
 324                         cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
 325
 326                         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 327                                 CaptureCard *card = &cards[card_index];
 328                                 card_copy[card_index].usb = card->usb;
 329                                 card_copy[card_index].new_data_ready = card->new_data_ready;
 330                                 card_copy[card_index].new_frame = card->new_frame;
 331                                 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
 332                                 card_copy[card_index].new_frame_audio = move(card->new_frame_audio);
 333                                 card_copy[card_index].dropped_frames = card->dropped_frames;
 334                                 card->new_data_ready = false;
 335                                 card->new_data_ready_changed.notify_all();
 336                         }
 337                 }
 338
 339                 // Resample the audio as needed, including from previously dropped frames.
 340                 vector<float> samples_out;
 341                 // TODO: Allow using audio from the other card(s) as well.
 342                 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
 343                         for (unsigned card_index = 0; card_index < NUM_CARDS; ++card_index) {
 344                                 samples_out.resize((48000 / 60) * 2);
 345                                 {
 346                                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
 347                                         if (!cards[card_index].resampler->get_output_samples(pts(), &samples_out[0], 48000 / 60)) {
 348                                                 printf("Card %d reported previous underrun.\n", card_index);
 349                                         }
 350                                 }
 351                                 if (card_index == 0) {
 352                                         h264_encoder->add_audio(pts_int, move(samples_out));
 353                                 }
 354                         }
 355                         if (frame_num != card_copy[0].dropped_frames) {
 356                                 // For dropped frames, increase the pts.
 357                                 ++dropped_frames;
 358                                 pts_int += TIMEBASE / 60;
 359                         }
 360                 }
 361
 362                 // If the first card is reporting a corrupted or otherwise dropped frame,
 363                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 364                 if (card_copy[0].new_frame->len == 0) {
 365                         ++dropped_frames;
 366                         pts_int += TIMEBASE / 60;
 367                         continue;
 368                 }
 369
 370                 for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 371                         CaptureCard *card = &card_copy[card_index];
 372                         if (!card->new_data_ready || card->new_frame->len == 0)
 373                                 continue;
 374
 375                         assert(card->new_frame != nullptr);
 376                         bmusb_current_rendering_frame[card_index] = card->new_frame;
 377                         check_error();
 378
 379                         // The new texture might still be uploaded,
 380                         // tell the GPU to wait until it's there.
 381                         if (card->new_data_ready_fence) {
 382                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
 383                                 check_error();
 384                                 glDeleteSync(card->new_data_ready_fence);
 385                                 check_error();
 386                         }
 387                         const PBOFrameAllocator::Userdata *userdata = (const PBOFrameAllocator::Userdata *)card->new_frame->userdata;
 388                         theme->set_input_textures(card_index, userdata->tex_y, userdata->tex_cbcr);
 389                 }
 390
 391                 // Get the main chain from the theme, and set its state immediately.
 392                 pair<EffectChain *, function<void()>> theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT);
 393                 EffectChain *chain = theme_main_chain.first;
 394                 theme_main_chain.second();
 395
 396                 GLuint y_tex, cbcr_tex;
 397                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
 398                 assert(got_frame);
 399
 400                 // Render main chain.
 401                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 402                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 403                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 404                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 405                 resource_pool->release_fbo(fbo);
 406
 407                 subsample_chroma(cbcr_full_tex, cbcr_tex);
 408                 resource_pool->release_2d_texture(cbcr_full_tex);
 409
 410                 // Set the right state for rgba_tex.
 411                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
 412                 glBindTexture(GL_TEXTURE_2D, rgba_tex);
 413                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 414                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 415                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 416
 417                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 418                 check_error();
 419
 420                 // Make sure the H.264 gets a reference to all the
 421                 // input frames needed, so that they are not released back
 422                 // until the rendering is done.
 423                 vector<RefCountedFrame> input_frames;
 424                 for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 425                         input_frames.push_back(bmusb_current_rendering_frame[card_index]);
 426                 }
 427                 const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampler.h. TODO: Make less hard-coded.
 428                 h264_encoder->end_frame(fence, pts_int + av_delay, input_frames);
 429                 ++frame;
 430                 pts_int += TIMEBASE / 60;
 431
 432                 // The live frame just shows the RGBA texture we just rendered.
 433                 // It owns rgba_tex now.
 434                 DisplayFrame live_frame;
 435                 live_frame.chain = display_chain.get();
 436                 live_frame.setup_chain = [this, rgba_tex]{
 437                         display_input->set_texture_num(rgba_tex);
 438                 };
 439                 live_frame.ready_fence = fence;
 440                 live_frame.input_frames = {};
 441                 live_frame.temp_textures = { rgba_tex };
 442                 output_channel[OUTPUT_LIVE].output_frame(live_frame);
 443
 444                 // Set up preview and any additional channels.
 445                 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 446                         DisplayFrame display_frame;
 447                         pair<EffectChain *, function<void()>> chain = theme->get_chain(i, pts(), WIDTH, HEIGHT);  // FIXME: dimensions
 448                         display_frame.chain = chain.first;
 449                         display_frame.setup_chain = chain.second;
 450                         display_frame.ready_fence = fence;
 451                         display_frame.input_frames = { bmusb_current_rendering_frame[0], bmusb_current_rendering_frame[1] };  // FIXME: possible to do better?
 452                         display_frame.temp_textures = {};
 453                         output_channel[i].output_frame(display_frame);
 454                 }
 455
 456                 clock_gettime(CLOCK_MONOTONIC, &now);
 457                 double elapsed = now.tv_sec - start.tv_sec +
 458                         1e-9 * (now.tv_nsec - start.tv_nsec);
 459                 if (frame % 100 == 0) {
 460                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
 461                                 frame, dropped_frames, elapsed, frame / elapsed,
 462                                 1e3 * elapsed / frame);
 463                 //      chain->print_phase_timing();
 464                 }
 465
 466 #if 0
 467                 // Reset every 100 frames, so that local variations in frame times
 468                 // (especially for the first few frames, when the shaders are
 469                 // compiled etc.) don't make it hard to measure for the entire
 470                 // remaining duration of the program.
 471                 if (frame == 10000) {
 472                         frame = 0;
 473                         start = now;
 474                 }
 475 #endif
 476                 check_error();
 477         }
 478
 479         resource_pool->clean_context();
 480 }
 481
 482 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 483 {
 484         GLuint vao;
 485         glGenVertexArrays(1, &vao);
 486         check_error();
 487
 488         float vertices[] = {
 489                 0.0f, 2.0f,
 490                 0.0f, 0.0f,
 491                 2.0f, 0.0f
 492         };
 493
 494         glBindVertexArray(vao);
 495         check_error();
 496
 497         // Extract Cb/Cr.
 498         GLuint fbo = resource_pool->create_fbo(dst_tex);
 499         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 500         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 501         check_error();
 502
 503         glUseProgram(cbcr_program_num);
 504         check_error();
 505
 506         glActiveTexture(GL_TEXTURE0);
 507         check_error();
 508         glBindTexture(GL_TEXTURE_2D, src_tex);
 509         check_error();
 510         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 511         check_error();
 512         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 513         check_error();
 514         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 515         check_error();
 516
 517         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 518         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 519
 520         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
 521         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
 522
 523         glDrawArrays(GL_TRIANGLES, 0, 3);
 524         check_error();
 525
 526         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
 527         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
 528
 529         glUseProgram(0);
 530         check_error();
 531
 532         resource_pool->release_fbo(fbo);
 533         glDeleteVertexArrays(1, &vao);
 534 }
 535
 536 void Mixer::release_display_frame(DisplayFrame *frame)
 537 {
 538         for (GLuint texnum : frame->temp_textures) {
 539                 resource_pool->release_2d_texture(texnum);
 540         }
 541         frame->temp_textures.clear();
 542         frame->ready_fence.reset();
 543         frame->input_frames.clear();
 544 }
 545
 546 void Mixer::start()
 547 {
 548         mixer_thread = thread(&Mixer::thread_func, this);
 549 }
 550
 551 void Mixer::quit()
 552 {
 553         should_quit = true;
 554         mixer_thread.join();
 555 }
 556
 557 void Mixer::transition_clicked(int transition_num)
 558 {
 559         theme->transition_clicked(transition_num, pts());
 560 }
 561
 562 void Mixer::channel_clicked(int preview_num)
 563 {
 564         theme->channel_clicked(preview_num);
 565 }
 566
 567 Mixer::OutputChannel::~OutputChannel()
 568 {
 569         if (has_current_frame) {
 570                 parent->release_display_frame(&current_frame);
 571         }
 572         if (has_ready_frame) {
 573                 parent->release_display_frame(&ready_frame);
 574         }
 575 }
 576
 577 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
 578 {
 579         // Store this frame for display. Remove the ready frame if any
 580         // (it was seemingly never used).
 581         {
 582                 unique_lock<mutex> lock(frame_mutex);
 583                 if (has_ready_frame) {
 584                         parent->release_display_frame(&ready_frame);
 585                 }
 586                 ready_frame = frame;
 587                 has_ready_frame = true;
 588         }
 589
 590         if (has_new_frame_ready_callback) {
 591                 new_frame_ready_callback();
 592         }
 593 }
 594
 595 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
 596 {
 597         unique_lock<mutex> lock(frame_mutex);
 598         if (!has_current_frame && !has_ready_frame) {
 599                 return false;
 600         }
 601
 602         if (has_current_frame && has_ready_frame) {
 603                 // We have a new ready frame. Toss the current one.
 604                 parent->release_display_frame(&current_frame);
 605                 has_current_frame = false;
 606         }
 607         if (has_ready_frame) {
 608                 assert(!has_current_frame);
 609                 current_frame = ready_frame;
 610                 ready_frame.ready_fence.reset();  // Drop the refcount.
 611                 ready_frame.input_frames.clear();  // Drop the refcounts.
 612                 has_current_frame = true;
 613                 has_ready_frame = false;
 614         }
 615
 616         *frame = current_frame;
 617         return true;
 618 }
 619
 620 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
 621 {
 622         new_frame_ready_callback = callback;
 623         has_new_frame_ready_callback = true;
 624 }