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