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.h"
  40 #include "context.h"
  41 #include "h264encode.h"
  42 #include "pbo_frame_allocator.h"
  43 #include "ref_counted_gl_sync.h"
  44
  45 class QOpenGLContext;
  46
  47 using namespace movit;
  48 using namespace std;
  49 using namespace std::placeholders;
  50
  51 Mixer *global_mixer = nullptr;
  52
  53 Mixer::Mixer(const QSurfaceFormat &format)
  54         : mixer_surface(create_surface(format)),
  55           h264_encoder_surface(create_surface(format))
  56 {
  57         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
  58         check_error();
  59
  60         resource_pool.reset(new ResourcePool);
  61         output_channel[OUTPUT_LIVE].parent = this;
  62         output_channel[OUTPUT_PREVIEW].parent = this;
  63
  64         ImageFormat inout_format;
  65         inout_format.color_space = COLORSPACE_sRGB;
  66         inout_format.gamma_curve = GAMMA_sRGB;
  67
  68         YCbCrFormat input_ycbcr_format;
  69         input_ycbcr_format.chroma_subsampling_x = 2;
  70         input_ycbcr_format.chroma_subsampling_y = 1;
  71         input_ycbcr_format.cb_x_position = 0.0;
  72         input_ycbcr_format.cr_x_position = 0.0;
  73         input_ycbcr_format.cb_y_position = 0.5;
  74         input_ycbcr_format.cr_y_position = 0.5;
  75         input_ycbcr_format.luma_coefficients = YCBCR_REC_601;
  76         input_ycbcr_format.full_range = false;
  77
  78         YCbCrFormat output_ycbcr_format;
  79         output_ycbcr_format.chroma_subsampling_x = 1;
  80         output_ycbcr_format.chroma_subsampling_y = 1;
  81         output_ycbcr_format.luma_coefficients = YCBCR_REC_601;
  82         output_ycbcr_format.full_range = false;
  83
  84         // Main chain.
  85         chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
  86         check_error();
  87         input[0] = new YCbCrInput(inout_format, input_ycbcr_format, WIDTH, HEIGHT, YCBCR_INPUT_SPLIT_Y_AND_CBCR);
  88         chain->add_input(input[0]);
  89         input[1] = new YCbCrInput(inout_format, input_ycbcr_format, WIDTH, HEIGHT, YCBCR_INPUT_SPLIT_Y_AND_CBCR);
  90         chain->add_input(input[1]);
  91         resample_effect = chain->add_effect(new ResampleEffect(), input[0]);
  92         padding_effect = chain->add_effect(new IntegralPaddingEffect());
  93         float border_color[] = { 0.0f, 0.0f, 0.0f, 1.0f };
  94         CHECK(padding_effect->set_vec4("border_color", border_color));
  95
  96         resample2_effect = chain->add_effect(new ResampleEffect(), input[1]);
  97         Effect *saturation_effect = chain->add_effect(new SaturationEffect());
  98         CHECK(saturation_effect->set_float("saturation", 0.3f));
  99         Effect *wb_effect = chain->add_effect(new WhiteBalanceEffect());
 100         CHECK(wb_effect->set_float("output_color_temperature", 3500.0));
 101         padding2_effect = chain->add_effect(new IntegralPaddingEffect());
 102
 103         chain->add_effect(new OverlayEffect(), padding_effect, padding2_effect);
 104
 105         chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 106         chain->add_ycbcr_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED, output_ycbcr_format, YCBCR_OUTPUT_SPLIT_Y_AND_CBCR);
 107         chain->set_dither_bits(8);
 108         chain->set_output_origin(OUTPUT_ORIGIN_TOP_LEFT);
 109         chain->finalize();
 110
 111         // Preview chain (always shows just first input for now).
 112         preview_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 113         check_error();
 114         preview_input = new YCbCrInput(inout_format, input_ycbcr_format, WIDTH, HEIGHT, YCBCR_INPUT_SPLIT_Y_AND_CBCR);
 115         preview_chain->add_input(preview_input);
 116         preview_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 117         preview_chain->set_dither_bits(0);  // Don't bother.
 118         preview_chain->set_output_origin(OUTPUT_ORIGIN_TOP_LEFT);
 119         preview_chain->finalize();
 120
 121         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, "test.mp4"));
 122
 123         printf("Configuring first card...\n");
 124         cards[0].usb = new BMUSBCapture(0x1edb, 0xbd3b);  // 0xbd4f
 125         cards[0].usb->set_frame_callback(std::bind(&Mixer::bm_frame, this, 0, _1, _2, _3, _4, _5, _6, _7));
 126         cards[0].frame_allocator.reset(new PBOFrameAllocator(1280 * 750 * 2 + 44));
 127         cards[0].usb->set_video_frame_allocator(cards[0].frame_allocator.get());
 128         cards[0].usb->configure_card();
 129         cards[0].surface = create_surface(format);
 130 #if NUM_CARDS == 2
 131         cards[1].surface = create_surface(format);
 132 #endif
 133
 134         if (NUM_CARDS == 2) {
 135                 printf("Configuring second card...\n");
 136                 cards[1].usb = new BMUSBCapture(0x1edb, 0xbd4f);
 137                 cards[1].usb->set_frame_callback(std::bind(&Mixer::bm_frame, this, 1, _1, _2, _3, _4, _5, _6, _7));
 138                 cards[1].frame_allocator.reset(new PBOFrameAllocator(1280 * 750 * 2 + 44));
 139                 cards[1].usb->set_video_frame_allocator(cards[1].frame_allocator.get());
 140                 cards[1].usb->configure_card();
 141         }
 142
 143         BMUSBCapture::start_bm_thread();
 144
 145         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 146                 cards[card_index].usb->start_bm_capture();
 147                 input[card_index]->set_pixel_data(0, nullptr, 0);
 148                 input[card_index]->set_pixel_data(1, nullptr, 0);
 149         }
 150
 151         //chain->enable_phase_timing(true);
 152
 153         // Set up stuff for NV12 conversion.
 154
 155         // Cb/Cr shader.
 156         string cbcr_vert_shader = read_file("vs-cbcr.130.vert");
 157         string cbcr_frag_shader =
 158                 "#version 130 \n"
 159                 "in vec2 tc0; \n"
 160                 "uniform sampler2D cbcr_tex; \n"
 161                 "void main() { \n"
 162                 "    gl_FragColor = texture2D(cbcr_tex, tc0); \n"
 163                 "} \n";
 164         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader);
 165 }
 166
 167 Mixer::~Mixer()
 168 {
 169         resource_pool->release_glsl_program(cbcr_program_num);
 170         BMUSBCapture::stop_bm_thread();
 171 }
 172
 173 void Mixer::bm_frame(int card_index, uint16_t timecode,
 174                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 175                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
 176 {
 177         CaptureCard *card = &cards[card_index];
 178         if (!card->thread_initialized) {
 179                 printf("initializing context for bmusb thread %d\n", card_index);
 180                 eglBindAPI(EGL_OPENGL_API);
 181                 card->context = create_context();
 182                 if (!make_current(card->context, card->surface)) {
 183                         printf("failed to create bmusb context\n");
 184                         exit(1);
 185                 }
 186                 card->thread_initialized = true;
 187         }
 188
 189         if (video_frame.len - video_offset != 1280 * 750 * 2) {
 190                 printf("dropping frame with wrong length (%ld)\n", video_frame.len - video_offset);
 191                 FILE *fp = fopen("frame.raw", "wb");
 192                 fwrite(video_frame.data, video_frame.len, 1, fp);
 193                 fclose(fp);
 194                 //exit(1);
 195                 card->usb->get_video_frame_allocator()->release_frame(video_frame);
 196                 card->usb->get_audio_frame_allocator()->release_frame(audio_frame);
 197                 return;
 198         }
 199         {
 200                 // Wait until the previous frame was consumed.
 201                 std::unique_lock<std::mutex> lock(bmusb_mutex);
 202                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready; });
 203         }
 204         GLuint pbo = (GLint)(intptr_t)video_frame.userdata;
 205         check_error();
 206         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
 207         check_error();
 208         glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, video_frame.size);
 209         check_error();
 210         //glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 211         //check_error();
 212         GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 213         check_error();
 214         assert(fence != nullptr);
 215         {
 216                 std::unique_lock<std::mutex> lock(bmusb_mutex);
 217                 card->new_data_ready = true;
 218                 card->new_frame = video_frame;
 219                 card->new_data_ready_fence = fence;
 220                 card->new_data_ready_changed.notify_all();
 221         }
 222
 223         // Video frame will be released later.
 224         card->usb->get_audio_frame_allocator()->release_frame(audio_frame);
 225 }
 226
 227 void Mixer::place_rectangle(Effect *resample_effect, Effect *padding_effect, float x0, float y0, float x1, float y1)
 228 {
 229         float srcx0 = 0.0f;
 230         float srcx1 = 1.0f;
 231         float srcy0 = 0.0f;
 232         float srcy1 = 1.0f;
 233
 234         // Cull.
 235         if (x0 > 1280.0 || x1 < 0.0 || y0 > 720.0 || y1 < 0.0) {
 236                 CHECK(resample_effect->set_int("width", 1));
 237                 CHECK(resample_effect->set_int("height", 1));
 238                 CHECK(resample_effect->set_float("zoom_x", 1280.0));
 239                 CHECK(resample_effect->set_float("zoom_y", 720.0));
 240                 CHECK(padding_effect->set_int("left", 2000));
 241                 CHECK(padding_effect->set_int("top", 2000));
 242                 return;
 243         }
 244
 245         // Clip. (TODO: Clip on upper/left sides, too.)
 246         if (x1 > 1280.0) {
 247                 srcx1 = (1280.0 - x0) / (x1 - x0);
 248                 x1 = 1280.0;
 249         }
 250         if (y1 > 720.0) {
 251                 srcy1 = (720.0 - y0) / (y1 - y0);
 252                 y1 = 720.0;
 253         }
 254
 255         float x_subpixel_offset = x0 - floor(x0);
 256         float y_subpixel_offset = y0 - floor(y0);
 257
 258         // Resampling must be to an integral number of pixels. Round up,
 259         // and then add an extra pixel so we have some leeway for the border.
 260         int width = int(ceil(x1 - x0)) + 1;
 261         int height = int(ceil(y1 - y0)) + 1;
 262         CHECK(resample_effect->set_int("width", width));
 263         CHECK(resample_effect->set_int("height", height));
 264
 265         // Correct the discrepancy with zoom. (This will leave a small
 266         // excess edge of pixels and subpixels, which we'll correct for soon.)
 267         float zoom_x = (x1 - x0) / (width * (srcx1 - srcx0));
 268         float zoom_y = (y1 - y0) / (height * (srcy1 - srcy0));
 269         CHECK(resample_effect->set_float("zoom_x", zoom_x));
 270         CHECK(resample_effect->set_float("zoom_y", zoom_y));
 271         CHECK(resample_effect->set_float("zoom_center_x", 0.0f));
 272         CHECK(resample_effect->set_float("zoom_center_y", 0.0f));
 273
 274         // Padding must also be to a whole-pixel offset.
 275         CHECK(padding_effect->set_int("left", floor(x0)));
 276         CHECK(padding_effect->set_int("top", floor(y0)));
 277
 278         // Correct _that_ discrepancy by subpixel offset in the resampling.
 279         CHECK(resample_effect->set_float("left", -x_subpixel_offset / zoom_x));
 280         CHECK(resample_effect->set_float("top", -y_subpixel_offset / zoom_y));
 281
 282         // Finally, adjust the border so it is exactly where we want it.
 283         CHECK(padding_effect->set_float("border_offset_left", x_subpixel_offset));
 284         CHECK(padding_effect->set_float("border_offset_right", x1 - (floor(x0) + width)));
 285         CHECK(padding_effect->set_float("border_offset_top", y_subpixel_offset));
 286         CHECK(padding_effect->set_float("border_offset_bottom", y1 - (floor(y0) + height)));
 287 }
 288
 289 void Mixer::thread_func()
 290 {
 291         eglBindAPI(EGL_OPENGL_API);
 292         QOpenGLContext *context = create_context();
 293         if (!make_current(context, mixer_surface)) {
 294                 printf("oops\n");
 295                 exit(1);
 296         }
 297
 298         struct timespec start, now;
 299         clock_gettime(CLOCK_MONOTONIC, &start);
 300
 301         while (!should_quit) {
 302                 ++frame;
 303
 304                 //int width0 = lrintf(848 * (1.0 + 0.2 * sin(frame * 0.02)));
 305                 int width0 = 848;
 306                 int height0 = lrintf(width0 * 9.0 / 16.0);
 307
 308                 //float top0 = 96 + 48 * sin(frame * 0.005);
 309                 //float left0 = 96 + 48 * cos(frame * 0.006);
 310                 float top0 = 48;
 311                 float left0 = 16;
 312                 float bottom0 = top0 + height0;
 313                 float right0 = left0 + width0;
 314
 315                 int width1 = 384;
 316                 int height1 = 216;
 317
 318                 float bottom1 = 720 - 48;
 319                 float right1 = 1280 - 16;
 320                 float top1 = bottom1 - height1;
 321                 float left1 = right1 - width1;
 322
 323                 if (current_source == SOURCE_INPUT1) {
 324                         top0 = 0.0;
 325                         bottom0 = HEIGHT;
 326                         left0 = 0.0;
 327                         right0 = WIDTH;
 328
 329                         top1 = HEIGHT + 10;
 330                         bottom1 = HEIGHT + 20;
 331                         left1 = WIDTH + 10;
 332                         right1 = WIDTH + 20;
 333                 } else if (current_source == SOURCE_INPUT2) {
 334                         top1 = 0.0;
 335                         bottom1 = HEIGHT;
 336                         left1 = 0.0;
 337                         right1 = WIDTH;
 338
 339                         top0 = HEIGHT + 10;
 340                         bottom0 = HEIGHT + 20;
 341                         left0 = WIDTH + 10;
 342                         right0 = WIDTH + 20;
 343                 } else {
 344                         float t = 0.5 + 0.5 * cos(frame * 0.006);
 345                         float scale0 = 1.0 + t * (1280.0 / 848.0 - 1.0);
 346                         float tx0 = 0.0 + t * (-16.0 * scale0);
 347                         float ty0 = 0.0 + t * (-48.0 * scale0);
 348
 349                         top0 = top0 * scale0 + ty0;
 350                         bottom0 = bottom0 * scale0 + ty0;
 351                         left0 = left0 * scale0 + tx0;
 352                         right0 = right0 * scale0 + tx0;
 353
 354                         top1 = top1 * scale0 + ty0;
 355                         bottom1 = bottom1 * scale0 + ty0;
 356                         left1 = left1 * scale0 + tx0;
 357                         right1 = right1 * scale0 + tx0;
 358                 }
 359
 360                 place_rectangle(resample_effect, padding_effect, left0, top0, right0, bottom0);
 361                 place_rectangle(resample2_effect, padding2_effect, left1, top1, right1, bottom1);
 362
 363                 CaptureCard card_copy[NUM_CARDS];
 364
 365                 {
 366                         std::unique_lock<std::mutex> lock(bmusb_mutex);
 367
 368                         // The first card is the master timer, so wait for it to have a new frame.
 369                         // TODO: Make configurable, and with a timeout.
 370                         cards[0].new_data_ready_changed.wait(lock, [this]{ return cards[0].new_data_ready; });
 371
 372                         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 373                                 CaptureCard *card = &cards[card_index];
 374                                 card_copy[card_index].usb = card->usb;
 375                                 card_copy[card_index].new_data_ready = card->new_data_ready;
 376                                 card_copy[card_index].new_frame = card->new_frame;
 377                                 card_copy[card_index].new_data_ready_fence = card->new_data_ready_fence;
 378                                 card->new_data_ready = false;
 379                                 card->new_data_ready_changed.notify_all();
 380                         }
 381                 }
 382
 383                 vector<FrameAllocator::Frame> input_frames_to_release;
 384
 385                 for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 386                         CaptureCard *card = &card_copy[card_index];
 387                         if (!card->new_data_ready)
 388                                 continue;
 389
 390                         // Now we're done with the previous frame, so we can definitely
 391                         // release it when this is done rendering. (Actually, we could do
 392                         // it one frame earlier, but before we have a new one, there's no
 393                         // knowing when the current one is released.)
 394                         if (bmusb_current_rendering_frame[card_index].owner != nullptr) {
 395                                 input_frames_to_release.push_back(bmusb_current_rendering_frame[card_index]);
 396                         }
 397                         bmusb_current_rendering_frame[card_index] = card->new_frame;
 398                         check_error();
 399
 400                         // The new texture might still be uploaded,
 401                         // tell the GPU to wait until it's there.
 402                         if (card->new_data_ready_fence)
 403                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
 404                         check_error();
 405                         glDeleteSync(card->new_data_ready_fence);
 406                         check_error();
 407                         GLint input_tex_pbo = (GLint)(intptr_t)card->new_frame.userdata;
 408                         input[card_index]->set_pixel_data(0, (unsigned char *)BUFFER_OFFSET((1280 * 750 * 2 + 44) / 2 + 1280 * 25 + 22), input_tex_pbo);
 409                         input[card_index]->set_pixel_data(1, (unsigned char *)BUFFER_OFFSET(1280 * 25 + 22), input_tex_pbo);
 410
 411                         if (NUM_CARDS == 1) {
 412                                 // Set to the other one, too.
 413                                 input[1]->set_pixel_data(0, (unsigned char *)BUFFER_OFFSET((1280 * 750 * 2 + 44) / 2 + 1280 * 25 + 22), input_tex_pbo);
 414                                 input[1]->set_pixel_data(1, (unsigned char *)BUFFER_OFFSET(1280 * 25 + 22), input_tex_pbo);
 415                         }
 416
 417                         if (card_index == 0) {
 418                                 preview_input->set_pixel_data(0, (unsigned char *)BUFFER_OFFSET((1280 * 750 * 2 + 44) / 2 + 1280 * 25 + 22), input_tex_pbo);
 419                                 preview_input->set_pixel_data(1, (unsigned char *)BUFFER_OFFSET(1280 * 25 + 22), input_tex_pbo);
 420                         }
 421                 }
 422
 423                 GLuint y_tex, cbcr_tex;
 424                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
 425                 assert(got_frame);
 426
 427                 // Render main chain.
 428                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 429                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGBA8, WIDTH, HEIGHT);
 430                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 431                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 432                 resource_pool->release_fbo(fbo);
 433
 434                 subsample_chroma(cbcr_full_tex, cbcr_tex);
 435                 resource_pool->release_2d_texture(cbcr_full_tex);
 436
 437                 // Render preview chain.
 438                 GLuint preview_rgba_tex = resource_pool->create_2d_texture(GL_RGBA8, output_channel[OUTPUT_PREVIEW].width, output_channel[OUTPUT_PREVIEW].height);
 439                 fbo = resource_pool->create_fbo(preview_rgba_tex);
 440                 preview_chain->render_to_fbo(fbo, output_channel[OUTPUT_PREVIEW].width, output_channel[OUTPUT_PREVIEW].height);
 441                 resource_pool->release_fbo(fbo);
 442
 443                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 444                 check_error();
 445                 h264_encoder->end_frame(fence, input_frames_to_release);
 446
 447                 output_channel[OUTPUT_LIVE].output_frame(rgba_tex, fence);
 448                 output_channel[OUTPUT_PREVIEW].output_frame(preview_rgba_tex, fence);
 449
 450                 clock_gettime(CLOCK_MONOTONIC, &now);
 451                 double elapsed = now.tv_sec - start.tv_sec +
 452                         1e-9 * (now.tv_nsec - start.tv_nsec);
 453                 if (frame % 100 == 0) {
 454                         printf("%d frames in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
 455                                 frame, elapsed, frame / elapsed,
 456                                 1e3 * elapsed / frame);
 457                 //      chain->print_phase_timing();
 458                 }
 459
 460                 // Reset every 100 frames, so that local variations in frame times
 461                 // (especially for the first few frames, when the shaders are
 462                 // compiled etc.) don't make it hard to measure for the entire
 463                 // remaining duration of the program.
 464                 if (frame == 10000) {
 465                         frame = 0;
 466                         start = now;
 467                 }
 468                 check_error();
 469         }
 470 }
 471
 472 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 473 {
 474         GLuint vao;
 475         glGenVertexArrays(1, &vao);
 476         check_error();
 477
 478         float vertices[] = {
 479                 0.0f, 2.0f,
 480                 0.0f, 0.0f,
 481                 2.0f, 0.0f
 482         };
 483
 484         glBindVertexArray(vao);
 485         check_error();
 486
 487         // Extract Cb/Cr.
 488         GLuint fbo = resource_pool->create_fbo(dst_tex);
 489         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 490         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 491         check_error();
 492
 493         glUseProgram(cbcr_program_num);
 494         check_error();
 495
 496         glActiveTexture(GL_TEXTURE0);
 497         check_error();
 498         glBindTexture(GL_TEXTURE_2D, src_tex);
 499         check_error();
 500         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 501         check_error();
 502         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 503         check_error();
 504         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 505         check_error();
 506
 507         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 508         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 509
 510         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
 511         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
 512
 513         glDrawArrays(GL_TRIANGLES, 0, 3);
 514         check_error();
 515
 516         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
 517         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
 518
 519         glUseProgram(0);
 520         check_error();
 521
 522         resource_pool->release_fbo(fbo);
 523         glDeleteVertexArrays(1, &vao);
 524 }
 525
 526 void Mixer::release_display_frame(DisplayFrame *frame)
 527 {
 528         resource_pool->release_2d_texture(frame->texnum);
 529         frame->texnum = 0;
 530         frame->ready_fence.reset();
 531 }
 532
 533 void Mixer::start()
 534 {
 535         mixer_thread = std::thread(&Mixer::thread_func, this);
 536 }
 537
 538 void Mixer::quit()
 539 {
 540         should_quit = true;
 541         mixer_thread.join();
 542 }
 543
 544 void Mixer::cut(Source source)
 545 {
 546         current_source = source;
 547 }
 548
 549 void Mixer::OutputChannel::output_frame(GLuint tex, RefCountedGLsync fence)
 550 {
 551         // Store this frame for display. Remove the ready frame if any
 552         // (it was seemingly never used).
 553         {
 554                 std::unique_lock<std::mutex> lock(frame_mutex);
 555                 if (has_ready_frame) {
 556                         parent->release_display_frame(&ready_frame);
 557                 }
 558                 ready_frame.texnum = tex;
 559                 ready_frame.ready_fence = fence;
 560                 has_ready_frame = true;
 561         }
 562
 563         if (has_new_frame_ready_callback) {
 564                 new_frame_ready_callback();
 565         }
 566 }
 567
 568 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
 569 {
 570         std::unique_lock<std::mutex> lock(frame_mutex);
 571         if (!has_current_frame && !has_ready_frame) {
 572                 return false;
 573         }
 574
 575         if (has_current_frame && has_ready_frame) {
 576                 // We have a new ready frame. Toss the current one.
 577                 parent->release_display_frame(&current_frame);
 578                 has_current_frame = false;
 579         }
 580         if (has_ready_frame) {
 581                 assert(!has_current_frame);
 582                 current_frame = ready_frame;
 583                 ready_frame.ready_fence.reset();  // Drop the refcount.
 584                 has_current_frame = true;
 585                 has_ready_frame = false;
 586         }
 587
 588         *frame = current_frame;
 589         return true;
 590 }
 591
 592 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
 593 {
 594         new_frame_ready_callback = callback;
 595         has_new_frame_ready_callback = true;
 596 }
 597
 598 void Mixer::OutputChannel::set_size(int width, int height)
 599 {
 600         this->width = width;
 601         this->height = height;
 602 }