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

   1 #define WIDTH 1280
   2 #define HEIGHT 720
   3 #define EXTRAHEIGHT 30
   4
   5 #undef Success
   6
   7 #include "mixer.h"
   8
   9 #include <assert.h>
  10 #include <effect.h>
  11 #include <effect_chain.h>
  12 #include <effect_util.h>
  13 #include <epoxy/egl.h>
  14 #include <features.h>
  15 #include <image_format.h>
  16 #include <init.h>
  17 #include <overlay_effect.h>
  18 #include <padding_effect.h>
  19 #include <resample_effect.h>
  20 #include <resource_pool.h>
  21 #include <saturation_effect.h>
  22 #include <stdint.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <sys/time.h>
  26 #include <time.h>
  27 #include <util.h>
  28 #include <white_balance_effect.h>
  29 #include <ycbcr.h>
  30 #include <ycbcr_input.h>
  31 #include <cmath>
  32 #include <condition_variable>
  33 #include <cstddef>
  34 #include <memory>
  35 #include <mutex>
  36 #include <string>
  37 #include <thread>
  38 #include <vector>
  39
  40 #include "bmusb/bmusb.h"
  41 #include "context.h"
  42 #include "h264encode.h"
  43 #include "pbo_frame_allocator.h"
  44 #include "ref_counted_gl_sync.h"
  45 #include "timebase.h"
  46
  47 class QOpenGLContext;
  48
  49 using namespace movit;
  50 using namespace std;
  51 using namespace std::placeholders;
  52
  53 Mixer *global_mixer = nullptr;
  54
  55 namespace {
  56
  57 void convert_fixed24_to_fp32(float *dst, size_t out_channels, const uint8_t *src, size_t in_channels, size_t num_samples)
  58 {
  59         for (size_t i = 0; i < num_samples; ++i) {
  60                 for (size_t j = 0; j < out_channels; ++j) {
  61                         uint32_t s1 = *src++;
  62                         uint32_t s2 = *src++;
  63                         uint32_t s3 = *src++;
  64                         uint32_t s = s1 | (s1 << 8) | (s2 << 16) | (s3 << 24);
  65                         dst[i * out_channels + j] = int(s) * (1.0f / 4294967296.0f);
  66                 }
  67                 src += 3 * (in_channels - out_channels);
  68         }
  69 }
  70
  71 }  // namespace
  72
  73 Mixer::Mixer(const QSurfaceFormat &format)
  74         : httpd("test.ts", WIDTH, HEIGHT),
  75           mixer_surface(create_surface(format)),
  76           h264_encoder_surface(create_surface(format))
  77 {
  78         httpd.start(9095);
  79
  80         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
  81         check_error();
  82
  83         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
  84         // will be halved when sampling them, and we need to compensate here.
  85         movit_texel_subpixel_precision /= 2.0;
  86
  87         resource_pool.reset(new ResourcePool);
  88         theme.reset(new Theme("theme.lua", resource_pool.get()));
  89         output_channel[OUTPUT_LIVE].parent = this;
  90         output_channel[OUTPUT_PREVIEW].parent = this;
  91         output_channel[OUTPUT_INPUT0].parent = this;
  92         output_channel[OUTPUT_INPUT1].parent = this;
  93
  94         ImageFormat inout_format;
  95         inout_format.color_space = COLORSPACE_sRGB;
  96         inout_format.gamma_curve = GAMMA_sRGB;
  97
  98         // Display chain; shows the live output produced by the main chain (its RGBA version).
  99         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 100         check_error();
 101         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 102         display_chain->add_input(display_input);
 103         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 104         display_chain->set_dither_bits(0);  // Don't bother.
 105         display_chain->finalize();
 106
 107         h264_encoder.reset(new H264Encoder(h264_encoder_surface, WIDTH, HEIGHT, &httpd));
 108
 109         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 110                 printf("Configuring card %d...\n", card_index);
 111                 CaptureCard *card = &cards[card_index];
 112                 card->usb = new BMUSBCapture(card_index);
 113                 card->usb->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 114                 card->frame_allocator.reset(new PBOFrameAllocator(WIDTH * (HEIGHT+EXTRAHEIGHT) * 2 + 44, WIDTH, HEIGHT));
 115                 card->usb->set_video_frame_allocator(card->frame_allocator.get());
 116                 card->surface = create_surface(format);
 117                 card->usb->set_dequeue_thread_callbacks(
 118                         [card]{
 119                                 eglBindAPI(EGL_OPENGL_API);
 120                                 card->context = create_context();
 121                                 if (!make_current(card->context, card->surface)) {
 122                                         printf("failed to create bmusb context\n");
 123                                         exit(1);
 124                                 }
 125                         },
 126                         [this]{
 127                                 resource_pool->clean_context();
 128                         });
 129                 card->resampler.reset(new Resampler(48000.0, 48000.0, 2));
 130                 card->usb->configure_card();
 131         }
 132
 133         BMUSBCapture::start_bm_thread();
 134
 135         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 136                 cards[card_index].usb->start_bm_capture();
 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         r128.init(2, 48000);
 155         r128.integr_start();
 156 }
 157
 158 Mixer::~Mixer()
 159 {
 160         resource_pool->release_glsl_program(cbcr_program_num);
 161         BMUSBCapture::stop_bm_thread();
 162
 163         for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 164                 {
 165                         unique_lock<mutex> lock(bmusb_mutex);
 166                         cards[card_index].should_quit = true;  // Unblock thread.
 167                         cards[card_index].new_data_ready_changed.notify_all();
 168                 }
 169                 cards[card_index].usb->stop_dequeue_thread();
 170         }
 171 }
 172
 173 namespace {
 174
 175 int unwrap_timecode(uint16_t current_wrapped, int last)
 176 {
 177         uint16_t last_wrapped = last & 0xffff;
 178         if (current_wrapped > last_wrapped) {
 179                 return (last & ~0xffff) | current_wrapped;
 180         } else {
 181                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 182         }
 183 }
 184
 185 float find_peak(const vector<float> &samples)
 186 {
 187         float m = fabs(samples[0]);
 188         for (size_t i = 1; i < samples.size(); ++i) {
 189                 m = std::max(m, fabs(samples[i]));
 190         }
 191         return m;
 192 }
 193
 194 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 195 {
 196         size_t num_samples = in.size() / 2;
 197         out_l->resize(num_samples);
 198         out_r->resize(num_samples);
 199
 200         const float *inptr = in.data();
 201         float *lptr = &(*out_l)[0];
 202         float *rptr = &(*out_r)[0];
 203         for (size_t i = 0; i < num_samples; ++i) {
 204                 *lptr++ = *inptr++;
 205                 *rptr++ = *inptr++;
 206         }
 207 }
 208
 209 }  // namespace
 210
 211 void Mixer::bm_frame(int card_index, uint16_t timecode,
 212                      FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 213                      FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)
 214 {
 215         CaptureCard *card = &cards[card_index];
 216
 217         if (audio_frame.len - audio_offset > 30000) {
 218                 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",
 219                         card_index, int(audio_frame.len), int(audio_offset),
 220                         timecode, int(video_frame.len), int(video_offset), video_format);
 221                 if (video_frame.owner) {
 222                         video_frame.owner->release_frame(video_frame);
 223                 }
 224                 if (audio_frame.owner) {
 225                         audio_frame.owner->release_frame(audio_frame);
 226                 }
 227                 return;
 228         }
 229
 230         // Convert the audio to stereo fp32 and add it.
 231         size_t num_samples = (audio_frame.len - audio_offset) / 8 / 3;
 232         vector<float> audio;
 233         audio.resize(num_samples * 2);
 234         convert_fixed24_to_fp32(&audio[0], 2, audio_frame.data + audio_offset, 8, num_samples);
 235
 236         int unwrapped_timecode = timecode;
 237         int dropped_frames = 0;
 238         if (card->last_timecode != -1) {
 239                 unwrapped_timecode = unwrap_timecode(unwrapped_timecode, card->last_timecode);
 240                 dropped_frames = unwrapped_timecode - card->last_timecode - 1;
 241         }
 242         card->last_timecode = unwrapped_timecode;
 243
 244         // Add the audio.
 245         {
 246                 unique_lock<mutex> lock(card->audio_mutex);
 247
 248                 int unwrapped_timecode = timecode;
 249                 if (dropped_frames > 60 * 2) {
 250                         fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around), resetting resampler\n",
 251                                 card_index);
 252                         card->resampler.reset(new Resampler(48000.0, 48000.0, 2));
 253                 } else if (dropped_frames > 0) {
 254                         // Insert silence as needed.
 255                         fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 256                                 card_index, dropped_frames, timecode);
 257                         vector<float> silence;
 258                         silence.resize((48000 / 60) * 2);
 259                         for (int i = 0; i < dropped_frames; ++i) {
 260                                 card->resampler->add_input_samples((unwrapped_timecode - dropped_frames + i) / 60.0, silence.data(), (48000 / 60));
 261                         }
 262                 }
 263                 card->resampler->add_input_samples(unwrapped_timecode / 60.0, audio.data(), num_samples);
 264         }
 265
 266         // Done with the audio, so release it.
 267         if (audio_frame.owner) {
 268                 audio_frame.owner->release_frame(audio_frame);
 269         }
 270
 271         {
 272                 // Wait until the previous frame was consumed.
 273                 unique_lock<mutex> lock(bmusb_mutex);
 274                 card->new_data_ready_changed.wait(lock, [card]{ return !card->new_data_ready || card->should_quit; });
 275                 if (card->should_quit) return;
 276         }
 277
 278         if (video_frame.len - video_offset != WIDTH * (HEIGHT+EXTRAHEIGHT) * 2) {
 279                 if (video_frame.len != 0) {
 280                         printf("Card %d: Dropping video frame with wrong length (%ld)\n",
 281                                 card_index, video_frame.len - video_offset);
 282                 }
 283                 if (video_frame.owner) {
 284                         video_frame.owner->release_frame(video_frame);
 285                 }
 286
 287                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 288                 // so that pts can go up accordingly.
 289                 {
 290                         unique_lock<mutex> lock(bmusb_mutex);
 291                         card->new_data_ready = true;
 292                         card->new_frame = RefCountedFrame(FrameAllocator::Frame());
 293                         card->new_data_ready_fence = nullptr;
 294                         card->dropped_frames = dropped_frames;
 295                         card->new_data_ready_changed.notify_all();
 296                 }
 297                 return;
 298         }
 299
 300         const PBOFrameAllocator::Userdata *userdata = (const PBOFrameAllocator::Userdata *)video_frame.userdata;
 301         GLuint pbo = userdata->pbo;
 302         check_error();
 303         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
 304         check_error();
 305         glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, video_frame.size);
 306         check_error();
 307         //glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 308         //check_error();
 309
 310         // Upload the textures.
 311         glBindTexture(GL_TEXTURE_2D, userdata->tex_y);
 312         check_error();
 313         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, WIDTH, HEIGHT, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET((WIDTH * (HEIGHT+EXTRAHEIGHT) * 2 + 44) / 2 + WIDTH * 25 + 22));
 314         check_error();
 315         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr);
 316         check_error();
 317         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, WIDTH/2, HEIGHT, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(WIDTH * 25 + 22));
 318         check_error();
 319         glBindTexture(GL_TEXTURE_2D, 0);
 320         check_error();
 321         GLsync fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 322         check_error();
 323         assert(fence != nullptr);
 324
 325         {
 326                 unique_lock<mutex> lock(bmusb_mutex);
 327                 card->new_data_ready = true;
 328                 card->new_frame = RefCountedFrame(video_frame);
 329                 card->new_data_ready_fence = fence;
 330                 card->dropped_frames = dropped_frames;
 331                 card->new_data_ready_changed.notify_all();
 332         }
 333 }
 334
 335 void Mixer::thread_func()
 336 {
 337         eglBindAPI(EGL_OPENGL_API);
 338         QOpenGLContext *context = create_context();
 339         if (!make_current(context, mixer_surface)) {
 340                 printf("oops\n");
 341                 exit(1);
 342         }
 343
 344         struct timespec start, now;
 345         clock_gettime(CLOCK_MONOTONIC, &start);
 346
 347         int frame = 0;
 348         int dropped_frames = 0;
 349
 350         while (!should_quit) {
 351                 CaptureCard card_copy[NUM_CARDS];
 352
 353                 {
 354                         unique_lock<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_copy[card_index].new_frame_audio = move(card->new_frame_audio);
 367                                 card_copy[card_index].dropped_frames = card->dropped_frames;
 368                                 card->new_data_ready = false;
 369                                 card->new_data_ready_changed.notify_all();
 370                         }
 371                 }
 372
 373                 // Resample the audio as needed, including from previously dropped frames.
 374                 vector<float> samples_out;
 375                 // TODO: Allow using audio from the other card(s) as well.
 376                 for (unsigned frame_num = 0; frame_num < card_copy[0].dropped_frames + 1; ++frame_num) {
 377                         for (unsigned card_index = 0; card_index < NUM_CARDS; ++card_index) {
 378                                 samples_out.resize((48000 / 60) * 2);
 379                                 {
 380                                         unique_lock<mutex> lock(cards[card_index].audio_mutex);
 381                                         if (!cards[card_index].resampler->get_output_samples(pts(), &samples_out[0], 48000 / 60)) {
 382                                                 printf("Card %d reported previous underrun.\n", card_index);
 383                                         }
 384                                 }
 385                                 if (card_index == 0) {
 386                                         vector<float> left, right;
 387                                         peak = std::max(peak, find_peak(samples_out));
 388                                         deinterleave_samples(samples_out, &left, &right);
 389                                         float *ptrs[] = { left.data(), right.data() };
 390                                         r128.process(left.size(), ptrs);
 391                                         h264_encoder->add_audio(pts_int, move(samples_out));
 392                                 }
 393                         }
 394                         if (frame_num != card_copy[0].dropped_frames) {
 395                                 // For dropped frames, increase the pts.
 396                                 ++dropped_frames;
 397                                 pts_int += TIMEBASE / 60;
 398                         }
 399                 }
 400
 401                 if (audio_level_callback != nullptr) {
 402                         double loudness_s = r128.loudness_S();
 403                         double loudness_i = r128.integrated();
 404                         double loudness_range_low = r128.range_min();
 405                         double loudness_range_high = r128.range_max();
 406
 407                         audio_level_callback(loudness_s, 20.0 * log10(peak),
 408                                              loudness_i, loudness_range_low, loudness_range_high);
 409                 }
 410
 411                 // If the first card is reporting a corrupted or otherwise dropped frame,
 412                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 413                 if (card_copy[0].new_frame->len == 0) {
 414                         ++dropped_frames;
 415                         pts_int += TIMEBASE / 60;
 416                         continue;
 417                 }
 418
 419                 for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 420                         CaptureCard *card = &card_copy[card_index];
 421                         if (!card->new_data_ready || card->new_frame->len == 0)
 422                                 continue;
 423
 424                         assert(card->new_frame != nullptr);
 425                         bmusb_current_rendering_frame[card_index] = card->new_frame;
 426                         check_error();
 427
 428                         // The new texture might still be uploaded,
 429                         // tell the GPU to wait until it's there.
 430                         if (card->new_data_ready_fence) {
 431                                 glWaitSync(card->new_data_ready_fence, /*flags=*/0, GL_TIMEOUT_IGNORED);
 432                                 check_error();
 433                                 glDeleteSync(card->new_data_ready_fence);
 434                                 check_error();
 435                         }
 436                         const PBOFrameAllocator::Userdata *userdata = (const PBOFrameAllocator::Userdata *)card->new_frame->userdata;
 437                         theme->set_input_textures(card_index, userdata->tex_y, userdata->tex_cbcr);
 438                 }
 439
 440                 // Get the main chain from the theme, and set its state immediately.
 441                 pair<EffectChain *, function<void()>> theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT);
 442                 EffectChain *chain = theme_main_chain.first;
 443                 theme_main_chain.second();
 444
 445                 GLuint y_tex, cbcr_tex;
 446                 bool got_frame = h264_encoder->begin_frame(&y_tex, &cbcr_tex);
 447                 assert(got_frame);
 448
 449                 // Render main chain.
 450                 GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 451                 GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 452                 GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 453                 check_error();
 454                 chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 455                 resource_pool->release_fbo(fbo);
 456
 457                 subsample_chroma(cbcr_full_tex, cbcr_tex);
 458                 resource_pool->release_2d_texture(cbcr_full_tex);
 459
 460                 // Set the right state for rgba_tex.
 461                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
 462                 glBindTexture(GL_TEXTURE_2D, rgba_tex);
 463                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 464                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 465                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 466
 467                 RefCountedGLsync fence(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 468                 check_error();
 469
 470                 // Make sure the H.264 gets a reference to all the
 471                 // input frames needed, so that they are not released back
 472                 // until the rendering is done.
 473                 vector<RefCountedFrame> input_frames;
 474                 for (int card_index = 0; card_index < NUM_CARDS; ++card_index) {
 475                         input_frames.push_back(bmusb_current_rendering_frame[card_index]);
 476                 }
 477                 const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampler.h. TODO: Make less hard-coded.
 478                 h264_encoder->end_frame(fence, pts_int + av_delay, input_frames);
 479                 ++frame;
 480                 pts_int += TIMEBASE / 60;
 481
 482                 // The live frame just shows the RGBA texture we just rendered.
 483                 // It owns rgba_tex now.
 484                 DisplayFrame live_frame;
 485                 live_frame.chain = display_chain.get();
 486                 live_frame.setup_chain = [this, rgba_tex]{
 487                         display_input->set_texture_num(rgba_tex);
 488                 };
 489                 live_frame.ready_fence = fence;
 490                 live_frame.input_frames = {};
 491                 live_frame.temp_textures = { rgba_tex };
 492                 output_channel[OUTPUT_LIVE].output_frame(live_frame);
 493
 494                 // Set up preview and any additional channels.
 495                 for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 496                         DisplayFrame display_frame;
 497                         pair<EffectChain *, function<void()>> chain = theme->get_chain(i, pts(), WIDTH, HEIGHT);  // FIXME: dimensions
 498                         display_frame.chain = chain.first;
 499                         display_frame.setup_chain = chain.second;
 500                         display_frame.ready_fence = fence;
 501                         display_frame.input_frames = { bmusb_current_rendering_frame[0], bmusb_current_rendering_frame[1] };  // FIXME: possible to do better?
 502                         display_frame.temp_textures = {};
 503                         output_channel[i].output_frame(display_frame);
 504                 }
 505
 506                 clock_gettime(CLOCK_MONOTONIC, &now);
 507                 double elapsed = now.tv_sec - start.tv_sec +
 508                         1e-9 * (now.tv_nsec - start.tv_nsec);
 509                 if (frame % 100 == 0) {
 510                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)\n",
 511                                 frame, dropped_frames, elapsed, frame / elapsed,
 512                                 1e3 * elapsed / frame);
 513                 //      chain->print_phase_timing();
 514                 }
 515
 516 #if 0
 517                 // Reset every 100 frames, so that local variations in frame times
 518                 // (especially for the first few frames, when the shaders are
 519                 // compiled etc.) don't make it hard to measure for the entire
 520                 // remaining duration of the program.
 521                 if (frame == 10000) {
 522                         frame = 0;
 523                         start = now;
 524                 }
 525 #endif
 526                 check_error();
 527         }
 528
 529         resource_pool->clean_context();
 530 }
 531
 532 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 533 {
 534         GLuint vao;
 535         glGenVertexArrays(1, &vao);
 536         check_error();
 537
 538         float vertices[] = {
 539                 0.0f, 2.0f,
 540                 0.0f, 0.0f,
 541                 2.0f, 0.0f
 542         };
 543
 544         glBindVertexArray(vao);
 545         check_error();
 546
 547         // Extract Cb/Cr.
 548         GLuint fbo = resource_pool->create_fbo(dst_tex);
 549         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 550         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 551         check_error();
 552
 553         glUseProgram(cbcr_program_num);
 554         check_error();
 555
 556         glActiveTexture(GL_TEXTURE0);
 557         check_error();
 558         glBindTexture(GL_TEXTURE_2D, src_tex);
 559         check_error();
 560         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 561         check_error();
 562         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 563         check_error();
 564         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 565         check_error();
 566
 567         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 568         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 569
 570         GLuint position_vbo = fill_vertex_attribute(cbcr_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
 571         GLuint texcoord_vbo = fill_vertex_attribute(cbcr_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices);  // Same as vertices.
 572
 573         glDrawArrays(GL_TRIANGLES, 0, 3);
 574         check_error();
 575
 576         cleanup_vertex_attribute(cbcr_program_num, "position", position_vbo);
 577         cleanup_vertex_attribute(cbcr_program_num, "texcoord", texcoord_vbo);
 578
 579         glUseProgram(0);
 580         check_error();
 581
 582         resource_pool->release_fbo(fbo);
 583         glDeleteVertexArrays(1, &vao);
 584 }
 585
 586 void Mixer::release_display_frame(DisplayFrame *frame)
 587 {
 588         for (GLuint texnum : frame->temp_textures) {
 589                 resource_pool->release_2d_texture(texnum);
 590         }
 591         frame->temp_textures.clear();
 592         frame->ready_fence.reset();
 593         frame->input_frames.clear();
 594 }
 595
 596 void Mixer::start()
 597 {
 598         mixer_thread = thread(&Mixer::thread_func, this);
 599 }
 600
 601 void Mixer::quit()
 602 {
 603         should_quit = true;
 604         mixer_thread.join();
 605 }
 606
 607 void Mixer::transition_clicked(int transition_num)
 608 {
 609         theme->transition_clicked(transition_num, pts());
 610 }
 611
 612 void Mixer::channel_clicked(int preview_num)
 613 {
 614         theme->channel_clicked(preview_num);
 615 }
 616
 617 Mixer::OutputChannel::~OutputChannel()
 618 {
 619         if (has_current_frame) {
 620                 parent->release_display_frame(&current_frame);
 621         }
 622         if (has_ready_frame) {
 623                 parent->release_display_frame(&ready_frame);
 624         }
 625 }
 626
 627 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
 628 {
 629         // Store this frame for display. Remove the ready frame if any
 630         // (it was seemingly never used).
 631         {
 632                 unique_lock<mutex> lock(frame_mutex);
 633                 if (has_ready_frame) {
 634                         parent->release_display_frame(&ready_frame);
 635                 }
 636                 ready_frame = frame;
 637                 has_ready_frame = true;
 638         }
 639
 640         if (has_new_frame_ready_callback) {
 641                 new_frame_ready_callback();
 642         }
 643 }
 644
 645 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
 646 {
 647         unique_lock<mutex> lock(frame_mutex);
 648         if (!has_current_frame && !has_ready_frame) {
 649                 return false;
 650         }
 651
 652         if (has_current_frame && has_ready_frame) {
 653                 // We have a new ready frame. Toss the current one.
 654                 parent->release_display_frame(&current_frame);
 655                 has_current_frame = false;
 656         }
 657         if (has_ready_frame) {
 658                 assert(!has_current_frame);
 659                 current_frame = ready_frame;
 660                 ready_frame.ready_fence.reset();  // Drop the refcount.
 661                 ready_frame.input_frames.clear();  // Drop the refcounts.
 662                 has_current_frame = true;
 663                 has_ready_frame = false;
 664         }
 665
 666         *frame = current_frame;
 667         return true;
 668 }
 669
 670 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
 671 {
 672         new_frame_ready_callback = callback;
 673         has_new_frame_ready_callback = true;
 674 }