git.sesse.net Git - nageru/blob - futatabi/video_stream.cpp

   1 #include "video_stream.h"
   2
   3 extern "C" {
   4 #include <libavformat/avformat.h>
   5 #include <libavformat/avio.h>
   6 }
   7
   8 #include "chroma_subsampler.h"
   9 #include "shared/context.h"
  10 #include "flags.h"
  11 #include "flow.h"
  12 #include "shared/httpd.h"
  13 #include "jpeg_frame_view.h"
  14 #include "movit/util.h"
  15 #include "shared/mux.h"
  16 #include "player.h"
  17 #include "util.h"
  18 #include "ycbcr_converter.h"
  19
  20 #include <epoxy/glx.h>
  21 #include <jpeglib.h>
  22 #include <unistd.h>
  23
  24 using namespace std;
  25 using namespace std::chrono;
  26
  27 extern HTTPD *global_httpd;
  28
  29 struct VectorDestinationManager {
  30         jpeg_destination_mgr pub;
  31         std::vector<uint8_t> dest;
  32
  33         VectorDestinationManager()
  34         {
  35                 pub.init_destination = init_destination_thunk;
  36                 pub.empty_output_buffer = empty_output_buffer_thunk;
  37                 pub.term_destination = term_destination_thunk;
  38         }
  39
  40         static void init_destination_thunk(j_compress_ptr ptr)
  41         {
  42                 ((VectorDestinationManager *)(ptr->dest))->init_destination();
  43         }
  44
  45         inline void init_destination()
  46         {
  47                 make_room(0);
  48         }
  49
  50         static boolean empty_output_buffer_thunk(j_compress_ptr ptr)
  51         {
  52                 return ((VectorDestinationManager *)(ptr->dest))->empty_output_buffer();
  53         }
  54
  55         inline bool empty_output_buffer()
  56         {
  57                 make_room(dest.size());  // Should ignore pub.free_in_buffer!
  58                 return true;
  59         }
  60
  61         inline void make_room(size_t bytes_used)
  62         {
  63                 dest.resize(bytes_used + 4096);
  64                 dest.resize(dest.capacity());
  65                 pub.next_output_byte = dest.data() + bytes_used;
  66                 pub.free_in_buffer = dest.size() - bytes_used;
  67         }
  68
  69         static void term_destination_thunk(j_compress_ptr ptr)
  70         {
  71                 ((VectorDestinationManager *)(ptr->dest))->term_destination();
  72         }
  73
  74         inline void term_destination()
  75         {
  76                 dest.resize(dest.size() - pub.free_in_buffer);
  77         }
  78 };
  79 static_assert(std::is_standard_layout<VectorDestinationManager>::value, "");
  80
  81 vector<uint8_t> encode_jpeg(const uint8_t *y_data, const uint8_t *cb_data, const uint8_t *cr_data, unsigned width, unsigned height)
  82 {
  83         VectorDestinationManager dest;
  84
  85         jpeg_compress_struct cinfo;
  86         jpeg_error_mgr jerr;
  87         cinfo.err = jpeg_std_error(&jerr);
  88         jpeg_create_compress(&cinfo);
  89
  90         cinfo.dest = (jpeg_destination_mgr *)&dest;
  91         cinfo.input_components = 3;
  92         cinfo.in_color_space = JCS_RGB;
  93         jpeg_set_defaults(&cinfo);
  94         constexpr int quality = 90;
  95         jpeg_set_quality(&cinfo, quality, /*force_baseline=*/false);
  96
  97         cinfo.image_width = width;
  98         cinfo.image_height = height;
  99         cinfo.raw_data_in = true;
 100         jpeg_set_colorspace(&cinfo, JCS_YCbCr);
 101         cinfo.comp_info[0].h_samp_factor = 2;
 102         cinfo.comp_info[0].v_samp_factor = 1;
 103         cinfo.comp_info[1].h_samp_factor = 1;
 104         cinfo.comp_info[1].v_samp_factor = 1;
 105         cinfo.comp_info[2].h_samp_factor = 1;
 106         cinfo.comp_info[2].v_samp_factor = 1;
 107         cinfo.CCIR601_sampling = true;  // Seems to be mostly ignored by libjpeg, though.
 108         jpeg_start_compress(&cinfo, true);
 109
 110         // This comment marker is private to FFmpeg. It signals limited Y'CbCr range
 111         // (and nothing else).
 112         jpeg_write_marker(&cinfo, JPEG_COM, (const JOCTET *)"CS=ITU601", strlen("CS=ITU601"));
 113
 114         JSAMPROW yptr[8], cbptr[8], crptr[8];
 115         JSAMPARRAY data[3] = { yptr, cbptr, crptr };
 116         for (unsigned y = 0; y < height; y += 8) {
 117                 for (unsigned yy = 0; yy < 8; ++yy) {
 118                         yptr[yy] = const_cast<JSAMPROW>(&y_data[(y + yy) * width]);
 119                         cbptr[yy] = const_cast<JSAMPROW>(&cb_data[(y + yy) * width / 2]);
 120                         crptr[yy] = const_cast<JSAMPROW>(&cr_data[(y + yy) * width / 2]);
 121                 }
 122
 123                 jpeg_write_raw_data(&cinfo, data, /*num_lines=*/8);
 124         }
 125
 126         jpeg_finish_compress(&cinfo);
 127         jpeg_destroy_compress(&cinfo);
 128
 129         return move(dest.dest);
 130 }
 131
 132 VideoStream::VideoStream()
 133 {
 134         ycbcr_converter.reset(new YCbCrConverter(YCbCrConverter::OUTPUT_TO_DUAL_YCBCR, /*resource_pool=*/nullptr));
 135         ycbcr_semiplanar_converter.reset(new YCbCrConverter(YCbCrConverter::OUTPUT_TO_SEMIPLANAR, /*resource_pool=*/nullptr));
 136
 137         GLuint input_tex[num_interpolate_slots], gray_tex[num_interpolate_slots];
 138         GLuint fade_y_output_tex[num_interpolate_slots], fade_cbcr_output_tex[num_interpolate_slots];
 139         GLuint cb_tex[num_interpolate_slots], cr_tex[num_interpolate_slots];
 140
 141         glCreateTextures(GL_TEXTURE_2D_ARRAY, num_interpolate_slots, input_tex);
 142         glCreateTextures(GL_TEXTURE_2D_ARRAY, num_interpolate_slots, gray_tex);
 143         glCreateTextures(GL_TEXTURE_2D, num_interpolate_slots, fade_y_output_tex);
 144         glCreateTextures(GL_TEXTURE_2D, num_interpolate_slots, fade_cbcr_output_tex);
 145         glCreateTextures(GL_TEXTURE_2D, num_interpolate_slots, cb_tex);
 146         glCreateTextures(GL_TEXTURE_2D, num_interpolate_slots, cr_tex);
 147         check_error();
 148
 149         constexpr size_t width = 1280, height = 720;  // FIXME: adjustable width, height
 150         int levels = find_num_levels(width, height);
 151         for (size_t i = 0; i < num_interpolate_slots; ++i) {
 152                 glTextureStorage3D(input_tex[i], levels, GL_RGBA8, width, height, 2);
 153                 check_error();
 154                 glTextureStorage3D(gray_tex[i], levels, GL_R8, width, height, 2);
 155                 check_error();
 156                 glTextureStorage2D(fade_y_output_tex[i], 1, GL_R8, width, height);
 157                 check_error();
 158                 glTextureStorage2D(fade_cbcr_output_tex[i], 1, GL_RG8, width, height);
 159                 check_error();
 160                 glTextureStorage2D(cb_tex[i], 1, GL_R8, width / 2, height);
 161                 check_error();
 162                 glTextureStorage2D(cr_tex[i], 1, GL_R8, width / 2, height);
 163                 check_error();
 164
 165                 unique_ptr<InterpolatedFrameResources> resource(new InterpolatedFrameResources);
 166                 resource->owner = this;
 167                 resource->input_tex = input_tex[i];
 168                 resource->gray_tex = gray_tex[i];
 169                 resource->fade_y_output_tex = fade_y_output_tex[i];
 170                 resource->fade_cbcr_output_tex = fade_cbcr_output_tex[i];
 171                 resource->cb_tex = cb_tex[i];
 172                 resource->cr_tex = cr_tex[i];
 173                 glCreateFramebuffers(2, resource->input_fbos);
 174                 check_error();
 175                 glCreateFramebuffers(1, &resource->fade_fbo);
 176                 check_error();
 177
 178                 glNamedFramebufferTextureLayer(resource->input_fbos[0], GL_COLOR_ATTACHMENT0, input_tex[i], 0, 0);
 179                 check_error();
 180                 glNamedFramebufferTextureLayer(resource->input_fbos[0], GL_COLOR_ATTACHMENT1, gray_tex[i], 0, 0);
 181                 check_error();
 182                 glNamedFramebufferTextureLayer(resource->input_fbos[1], GL_COLOR_ATTACHMENT0, input_tex[i], 0, 1);
 183                 check_error();
 184                 glNamedFramebufferTextureLayer(resource->input_fbos[1], GL_COLOR_ATTACHMENT1, gray_tex[i], 0, 1);
 185                 check_error();
 186                 glNamedFramebufferTexture(resource->fade_fbo, GL_COLOR_ATTACHMENT0, fade_y_output_tex[i], 0);
 187                 check_error();
 188                 glNamedFramebufferTexture(resource->fade_fbo, GL_COLOR_ATTACHMENT1, fade_cbcr_output_tex[i], 0);
 189                 check_error();
 190
 191                 GLuint bufs[] = { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1 };
 192                 glNamedFramebufferDrawBuffers(resource->input_fbos[0], 2, bufs);
 193                 check_error();
 194                 glNamedFramebufferDrawBuffers(resource->input_fbos[1], 2, bufs);
 195                 check_error();
 196                 glNamedFramebufferDrawBuffers(resource->fade_fbo, 2, bufs);
 197                 check_error();
 198
 199                 glCreateBuffers(1, &resource->pbo);
 200                 check_error();
 201                 glNamedBufferStorage(resource->pbo, width * height * 4, nullptr, GL_MAP_READ_BIT | GL_MAP_PERSISTENT_BIT);
 202                 check_error();
 203                 resource->pbo_contents = glMapNamedBufferRange(resource->pbo, 0, width * height * 4, GL_MAP_READ_BIT | GL_MAP_PERSISTENT_BIT);
 204                 interpolate_resources.push_back(move(resource));
 205         }
 206
 207         check_error();
 208
 209         OperatingPoint op;
 210         if (global_flags.interpolation_quality == 1) {
 211                 op = operating_point1;
 212         } else if (global_flags.interpolation_quality == 2) {
 213                 op = operating_point2;
 214         } else if (global_flags.interpolation_quality == 3) {
 215                 op = operating_point3;
 216         } else if (global_flags.interpolation_quality == 4) {
 217                 op = operating_point4;
 218         } else {
 219                 assert(false);
 220         }
 221
 222         compute_flow.reset(new DISComputeFlow(width, height, op));
 223         interpolate.reset(new Interpolate(op, /*split_ycbcr_output=*/true));
 224         interpolate_no_split.reset(new Interpolate(op, /*split_ycbcr_output=*/false));
 225         chroma_subsampler.reset(new ChromaSubsampler);
 226         check_error();
 227
 228         // The “last frame” is initially black.
 229         unique_ptr<uint8_t[]> y(new uint8_t[1280 * 720]);
 230         unique_ptr<uint8_t[]> cb_or_cr(new uint8_t[640 * 720]);
 231         memset(y.get(), 16, 1280 * 720);
 232         memset(cb_or_cr.get(), 128, 640 * 720);
 233         last_frame = encode_jpeg(y.get(), cb_or_cr.get(), cb_or_cr.get(), 1280, 720);
 234 }
 235
 236 VideoStream::~VideoStream() {}
 237
 238 void VideoStream::start()
 239 {
 240         AVFormatContext *avctx = avformat_alloc_context();
 241
 242         // We use Matroska, because it's pretty much the only mux where FFmpeg
 243         // allows writing chroma location to override JFIF's default center placement.
 244         // (Note that at the time of writing, however, FFmpeg does not correctly
 245         // _read_ this information!)
 246         avctx->oformat = av_guess_format("matroska", nullptr, nullptr);
 247
 248         uint8_t *buf = (uint8_t *)av_malloc(MUX_BUFFER_SIZE);
 249         avctx->pb = avio_alloc_context(buf, MUX_BUFFER_SIZE, 1, this, nullptr, nullptr, nullptr);
 250         avctx->pb->write_data_type = &VideoStream::write_packet2_thunk;
 251         avctx->pb->ignore_boundary_point = 1;
 252
 253         Mux::Codec video_codec = Mux::CODEC_MJPEG;
 254
 255         avctx->flags = AVFMT_FLAG_CUSTOM_IO;
 256
 257         string video_extradata;
 258
 259         constexpr int width = 1280, height = 720;  // Doesn't matter for MJPEG.
 260         stream_mux.reset(new Mux(avctx, width, height, video_codec, video_extradata, /*audio_codec_parameters=*/nullptr,
 261                 AVCOL_SPC_BT709, Mux::WITHOUT_AUDIO,
 262                 COARSE_TIMEBASE, /*write_callback=*/nullptr, Mux::WRITE_FOREGROUND, {}));
 263
 264
 265         encode_thread = thread(&VideoStream::encode_thread_func, this);
 266 }
 267
 268 void VideoStream::stop()
 269 {
 270         encode_thread.join();
 271 }
 272
 273 void VideoStream::clear_queue()
 274 {
 275         deque<QueuedFrame> q;
 276
 277         {
 278                 unique_lock<mutex> lock(queue_lock);
 279                 q = move(frame_queue);
 280         }
 281
 282         // These are not RAII-ed, unfortunately, so we'll need to clean them ourselves.
 283         // Note that release_texture() is thread-safe.
 284         for (const QueuedFrame &qf : q) {
 285                 if (qf.type == QueuedFrame::INTERPOLATED ||
 286                     qf.type == QueuedFrame::FADED_INTERPOLATED) {
 287                         compute_flow->release_texture(qf.flow_tex);
 288                 }
 289                 if (qf.type == QueuedFrame::INTERPOLATED) {
 290                         interpolate->release_texture(qf.output_tex);
 291                         interpolate->release_texture(qf.cbcr_tex);
 292                 }
 293         }
 294
 295         // Destroy q outside the mutex, as that would be a double-lock.
 296 }
 297
 298 void VideoStream::schedule_original_frame(steady_clock::time_point local_pts,
 299                                           int64_t output_pts, function<void()> &&display_func,
 300                                           QueueSpotHolder &&queue_spot_holder,
 301                                           FrameOnDisk frame)
 302 {
 303         fprintf(stderr, "output_pts=%ld  original      input_pts=%ld\n", output_pts, frame.pts);
 304
 305         // Preload the file from disk, so that the encoder thread does not get stalled.
 306         // TODO: Consider sending it through the queue instead.
 307         (void)frame_reader.read_frame(frame);
 308
 309         QueuedFrame qf;
 310         qf.local_pts = local_pts;
 311         qf.type = QueuedFrame::ORIGINAL;
 312         qf.output_pts = output_pts;
 313         qf.frame1 = frame;
 314         qf.display_func = move(display_func);
 315         qf.queue_spot_holder = move(queue_spot_holder);
 316
 317         unique_lock<mutex> lock(queue_lock);
 318         frame_queue.push_back(move(qf));
 319         queue_changed.notify_all();
 320 }
 321
 322 void VideoStream::schedule_faded_frame(steady_clock::time_point local_pts, int64_t output_pts,
 323                                        function<void()> &&display_func,
 324                                        QueueSpotHolder &&queue_spot_holder,
 325                                        FrameOnDisk frame1_spec, FrameOnDisk frame2_spec,
 326                                        float fade_alpha)
 327 {
 328         fprintf(stderr, "output_pts=%ld  faded         input_pts=%ld,%ld  fade_alpha=%.2f\n", output_pts, frame1_spec.pts, frame2_spec.pts, fade_alpha);
 329
 330         // Get the temporary OpenGL resources we need for doing the fade.
 331         // (We share these with interpolated frames, which is slightly
 332         // overkill, but there's no need to waste resources on keeping
 333         // separate pools around.)
 334         BorrowedInterpolatedFrameResources resources;
 335         {
 336                 unique_lock<mutex> lock(queue_lock);
 337                 if (interpolate_resources.empty()) {
 338                         fprintf(stderr, "WARNING: Too many interpolated frames already in transit; dropping one.\n");
 339                         return;
 340                 }
 341                 resources = BorrowedInterpolatedFrameResources(interpolate_resources.front().release());
 342                 interpolate_resources.pop_front();
 343         }
 344
 345         bool did_decode;
 346
 347         shared_ptr<Frame> frame1 = decode_jpeg_with_cache(frame1_spec, DECODE_IF_NOT_IN_CACHE, &frame_reader, &did_decode);
 348         shared_ptr<Frame> frame2 = decode_jpeg_with_cache(frame2_spec, DECODE_IF_NOT_IN_CACHE, &frame_reader, &did_decode);
 349
 350         ycbcr_semiplanar_converter->prepare_chain_for_fade(frame1, frame2, fade_alpha)->render_to_fbo(resources->fade_fbo, 1280, 720);
 351
 352         QueuedFrame qf;
 353         qf.local_pts = local_pts;
 354         qf.type = QueuedFrame::FADED;
 355         qf.output_pts = output_pts;
 356         qf.frame1 = frame1_spec;
 357         qf.display_func = move(display_func);
 358         qf.queue_spot_holder = move(queue_spot_holder);
 359
 360         qf.secondary_frame = frame2_spec;
 361
 362         // Subsample and split Cb/Cr.
 363         chroma_subsampler->subsample_chroma(resources->fade_cbcr_output_tex, 1280, 720, resources->cb_tex, resources->cr_tex);
 364
 365         // Read it down (asynchronously) to the CPU.
 366         glPixelStorei(GL_PACK_ROW_LENGTH, 0);
 367         glBindBuffer(GL_PIXEL_PACK_BUFFER, resources->pbo);
 368         check_error();
 369         glGetTextureImage(resources->fade_y_output_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 4, BUFFER_OFFSET(0));
 370         check_error();
 371         glGetTextureImage(resources->cb_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 3, BUFFER_OFFSET(1280 * 720));
 372         check_error();
 373         glGetTextureImage(resources->cr_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 3 - 640 * 720, BUFFER_OFFSET(1280 * 720 + 640 * 720));
 374         check_error();
 375         glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
 376
 377         // Set a fence we can wait for to make sure the CPU sees the read.
 378         glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 379         check_error();
 380         qf.fence = RefCountedGLsync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 381         check_error();
 382         qf.resources = move(resources);
 383         qf.local_pts = local_pts;
 384
 385         unique_lock<mutex> lock(queue_lock);
 386         frame_queue.push_back(move(qf));
 387         queue_changed.notify_all();
 388 }
 389
 390 void VideoStream::schedule_interpolated_frame(steady_clock::time_point local_pts,
 391                                               int64_t output_pts, function<void(shared_ptr<Frame>)> &&display_func,
 392                                               QueueSpotHolder &&queue_spot_holder,
 393                                               FrameOnDisk frame1, FrameOnDisk frame2,
 394                                               float alpha, FrameOnDisk secondary_frame, float fade_alpha)
 395 {
 396         if (secondary_frame.pts != -1) {
 397                 fprintf(stderr, "output_pts=%ld  interpolated  input_pts1=%ld input_pts2=%ld alpha=%.3f  secondary_pts=%ld  fade_alpha=%.2f\n", output_pts, frame1.pts, frame2.pts, alpha, secondary_frame.pts, fade_alpha);
 398         } else {
 399                 fprintf(stderr, "output_pts=%ld  interpolated  input_pts1=%ld input_pts2=%ld alpha=%.3f\n", output_pts, frame1.pts, frame2.pts, alpha);
 400         }
 401
 402         // Get the temporary OpenGL resources we need for doing the interpolation.
 403         BorrowedInterpolatedFrameResources resources;
 404         {
 405                 unique_lock<mutex> lock(queue_lock);
 406                 if (interpolate_resources.empty()) {
 407                         fprintf(stderr, "WARNING: Too many interpolated frames already in transit; dropping one.\n");
 408                         return;
 409                 }
 410                 resources = BorrowedInterpolatedFrameResources(interpolate_resources.front().release());
 411                 interpolate_resources.pop_front();
 412         }
 413
 414         QueuedFrame qf;
 415         qf.type = (secondary_frame.pts == -1) ? QueuedFrame::INTERPOLATED : QueuedFrame::FADED_INTERPOLATED;
 416         qf.output_pts = output_pts;
 417         qf.display_decoded_func = move(display_func);
 418         qf.queue_spot_holder = move(queue_spot_holder);
 419         qf.local_pts = local_pts;
 420
 421         check_error();
 422
 423         // Convert frame0 and frame1 to OpenGL textures.
 424         for (size_t frame_no = 0; frame_no < 2; ++frame_no) {
 425                 FrameOnDisk frame_spec = frame_no == 1 ? frame2 : frame1;
 426                 bool did_decode;
 427                 shared_ptr<Frame> frame = decode_jpeg_with_cache(frame_spec, DECODE_IF_NOT_IN_CACHE, &frame_reader, &did_decode);
 428                 ycbcr_converter->prepare_chain_for_conversion(frame)->render_to_fbo(resources->input_fbos[frame_no], 1280, 720);
 429         }
 430
 431         glGenerateTextureMipmap(resources->input_tex);
 432         check_error();
 433         glGenerateTextureMipmap(resources->gray_tex);
 434         check_error();
 435
 436         // Compute the interpolated frame.
 437         qf.flow_tex = compute_flow->exec(resources->gray_tex, DISComputeFlow::FORWARD_AND_BACKWARD, DISComputeFlow::DO_NOT_RESIZE_FLOW);
 438         check_error();
 439
 440         if (secondary_frame.pts != -1) {
 441                 // Fade. First kick off the interpolation.
 442                 tie(qf.output_tex, ignore) = interpolate_no_split->exec(resources->input_tex, resources->gray_tex, qf.flow_tex, 1280, 720, alpha);
 443                 check_error();
 444
 445                 // Now decode the image we are fading against.
 446                 bool did_decode;
 447                 shared_ptr<Frame> frame2 = decode_jpeg_with_cache(secondary_frame, DECODE_IF_NOT_IN_CACHE, &frame_reader, &did_decode);
 448
 449                 // Then fade against it, putting it into the fade Y' and CbCr textures.
 450                 ycbcr_semiplanar_converter->prepare_chain_for_fade_from_texture(qf.output_tex, 1280, 720, frame2, fade_alpha)->render_to_fbo(resources->fade_fbo, 1280, 720);
 451
 452                 // Subsample and split Cb/Cr.
 453                 chroma_subsampler->subsample_chroma(resources->fade_cbcr_output_tex, 1280, 720, resources->cb_tex, resources->cr_tex);
 454
 455                 interpolate_no_split->release_texture(qf.output_tex);
 456         } else {
 457                 tie(qf.output_tex, qf.cbcr_tex) = interpolate->exec(resources->input_tex, resources->gray_tex, qf.flow_tex, 1280, 720, alpha);
 458                 check_error();
 459
 460                 // Subsample and split Cb/Cr.
 461                 chroma_subsampler->subsample_chroma(qf.cbcr_tex, 1280, 720, resources->cb_tex, resources->cr_tex);
 462         }
 463
 464         // We could have released qf.flow_tex here, but to make sure we don't cause a stall
 465         // when trying to reuse it for the next frame, we can just as well hold on to it
 466         // and release it only when the readback is done.
 467
 468         // Read it down (asynchronously) to the CPU.
 469         glPixelStorei(GL_PACK_ROW_LENGTH, 0);
 470         glBindBuffer(GL_PIXEL_PACK_BUFFER, resources->pbo);
 471         check_error();
 472         if (secondary_frame.pts != -1) {
 473                 glGetTextureImage(resources->fade_y_output_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 4, BUFFER_OFFSET(0));
 474         } else {
 475                 glGetTextureImage(qf.output_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 4, BUFFER_OFFSET(0));
 476         }
 477         check_error();
 478         glGetTextureImage(resources->cb_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 3, BUFFER_OFFSET(1280 * 720));
 479         check_error();
 480         glGetTextureImage(resources->cr_tex, 0, GL_RED, GL_UNSIGNED_BYTE, 1280 * 720 * 3 - 640 * 720, BUFFER_OFFSET(1280 * 720 + 640 * 720));
 481         check_error();
 482         glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
 483
 484         // Set a fence we can wait for to make sure the CPU sees the read.
 485         glMemoryBarrier(GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT);
 486         check_error();
 487         qf.fence = RefCountedGLsync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 488         check_error();
 489         qf.resources = move(resources);
 490
 491         unique_lock<mutex> lock(queue_lock);
 492         frame_queue.push_back(move(qf));
 493         queue_changed.notify_all();
 494 }
 495
 496 void VideoStream::schedule_refresh_frame(steady_clock::time_point local_pts,
 497                                          int64_t output_pts, function<void()> &&display_func,
 498                                          QueueSpotHolder &&queue_spot_holder)
 499 {
 500         QueuedFrame qf;
 501         qf.type = QueuedFrame::REFRESH;
 502         qf.output_pts = output_pts;
 503         qf.display_func = move(display_func);
 504         qf.queue_spot_holder = move(queue_spot_holder);
 505
 506         unique_lock<mutex> lock(queue_lock);
 507         frame_queue.push_back(move(qf));
 508         queue_changed.notify_all();
 509 }
 510
 511 namespace {
 512
 513 shared_ptr<Frame> frame_from_pbo(void *contents, size_t width, size_t height)
 514 {
 515         size_t chroma_width = width / 2;
 516
 517         const uint8_t *y = (const uint8_t *)contents;
 518         const uint8_t *cb = (const uint8_t *)contents + width * height;
 519         const uint8_t *cr = (const uint8_t *)contents + width * height + chroma_width * height;
 520
 521         shared_ptr<Frame> frame(new Frame);
 522         frame->y.reset(new uint8_t[width * height]);
 523         frame->cb.reset(new uint8_t[chroma_width * height]);
 524         frame->cr.reset(new uint8_t[chroma_width * height]);
 525         for (unsigned yy = 0; yy < height; ++yy) {
 526                 memcpy(frame->y.get() + width * yy, y + width * yy, width);
 527                 memcpy(frame->cb.get() + chroma_width * yy, cb + chroma_width * yy, chroma_width);
 528                 memcpy(frame->cr.get() + chroma_width * yy, cr + chroma_width * yy, chroma_width);
 529         }
 530         frame->is_semiplanar = false;
 531         frame->width = width;
 532         frame->height = height;
 533         frame->chroma_subsampling_x = 2;
 534         frame->chroma_subsampling_y = 1;
 535         frame->pitch_y = width;
 536         frame->pitch_chroma = chroma_width;
 537         return frame;
 538 }
 539
 540 }  // namespace
 541
 542 void VideoStream::encode_thread_func()
 543 {
 544         pthread_setname_np(pthread_self(), "VideoStream");
 545         QSurface *surface = create_surface();
 546         QOpenGLContext *context = create_context(surface);
 547         bool ok = make_current(context, surface);
 548         if (!ok) {
 549                 fprintf(stderr, "Video stream couldn't get an OpenGL context\n");
 550                 exit(1);
 551         }
 552
 553         for ( ;; ) {
 554                 QueuedFrame qf;
 555                 {
 556                         unique_lock<mutex> lock(queue_lock);
 557
 558                         // Wait until we have a frame to play.
 559                         queue_changed.wait(lock, [this]{
 560                                 return !frame_queue.empty();
 561                         });
 562                         steady_clock::time_point frame_start = frame_queue.front().local_pts;
 563
 564                         // Now sleep until the frame is supposed to start (the usual case),
 565                         // _or_ clear_queue() happened.
 566                         bool aborted = queue_changed.wait_until(lock, frame_start, [this, frame_start]{
 567                                 return frame_queue.empty() || frame_queue.front().local_pts != frame_start;
 568                         });
 569                         if (aborted) {
 570                                 // clear_queue() happened, so don't play this frame after all.
 571                                 continue;
 572                         }
 573                         qf = move(frame_queue.front());
 574                         frame_queue.pop_front();
 575                 }
 576
 577                 if (qf.type == QueuedFrame::ORIGINAL) {
 578                         // Send the JPEG frame on, unchanged.
 579                         string jpeg = frame_reader.read_frame(qf.frame1);
 580                         AVPacket pkt;
 581                         av_init_packet(&pkt);
 582                         pkt.stream_index = 0;
 583                         pkt.data = (uint8_t *)jpeg.data();
 584                         pkt.size = jpeg.size();
 585                         stream_mux->add_packet(pkt, qf.output_pts, qf.output_pts);
 586
 587                         last_frame.assign(&jpeg[0], &jpeg[0] + jpeg.size());
 588                 } else if (qf.type == QueuedFrame::FADED) {
 589                         glClientWaitSync(qf.fence.get(), /*flags=*/0, GL_TIMEOUT_IGNORED);
 590
 591                         shared_ptr<Frame> frame = frame_from_pbo(qf.resources->pbo_contents, 1280, 720);
 592
 593                         // Now JPEG encode it, and send it on to the stream.
 594                         vector<uint8_t> jpeg = encode_jpeg(frame->y.get(), frame->cb.get(), frame->cr.get(), 1280, 720);
 595
 596                         AVPacket pkt;
 597                         av_init_packet(&pkt);
 598                         pkt.stream_index = 0;
 599                         pkt.data = (uint8_t *)jpeg.data();
 600                         pkt.size = jpeg.size();
 601                         stream_mux->add_packet(pkt, qf.output_pts, qf.output_pts);
 602                         last_frame = move(jpeg);
 603                 } else if (qf.type == QueuedFrame::INTERPOLATED || qf.type == QueuedFrame::FADED_INTERPOLATED) {
 604                         glClientWaitSync(qf.fence.get(), /*flags=*/0, GL_TIMEOUT_IGNORED);
 605
 606                         // Send it on to display.
 607                         shared_ptr<Frame> frame = frame_from_pbo(qf.resources->pbo_contents, 1280, 720);
 608                         if (qf.display_decoded_func != nullptr) {
 609                                 qf.display_decoded_func(frame);
 610                         }
 611
 612                         // Now JPEG encode it, and send it on to the stream.
 613                         vector<uint8_t> jpeg = encode_jpeg(frame->y.get(), frame->cb.get(), frame->cr.get(), 1280, 720);
 614                         compute_flow->release_texture(qf.flow_tex);
 615                         if (qf.type != QueuedFrame::FADED_INTERPOLATED) {
 616                                 interpolate->release_texture(qf.output_tex);
 617                                 interpolate->release_texture(qf.cbcr_tex);
 618                         }
 619
 620                         AVPacket pkt;
 621                         av_init_packet(&pkt);
 622                         pkt.stream_index = 0;
 623                         pkt.data = (uint8_t *)jpeg.data();
 624                         pkt.size = jpeg.size();
 625                         stream_mux->add_packet(pkt, qf.output_pts, qf.output_pts);
 626                         last_frame = move(jpeg);
 627                 } else if (qf.type == QueuedFrame::REFRESH) {
 628                         AVPacket pkt;
 629                         av_init_packet(&pkt);
 630                         pkt.stream_index = 0;
 631                         pkt.data = (uint8_t *)last_frame.data();
 632                         pkt.size = last_frame.size();
 633                         stream_mux->add_packet(pkt, qf.output_pts, qf.output_pts);
 634                 } else {
 635                         assert(false);
 636                 }
 637                 if (qf.display_func != nullptr) {
 638                         qf.display_func();
 639                 }
 640         }
 641 }
 642
 643 int VideoStream::write_packet2_thunk(void *opaque, uint8_t *buf, int buf_size, AVIODataMarkerType type, int64_t time)
 644 {
 645         VideoStream *video_stream = (VideoStream *)opaque;
 646         return video_stream->write_packet2(buf, buf_size, type, time);
 647 }
 648
 649 int VideoStream::write_packet2(uint8_t *buf, int buf_size, AVIODataMarkerType type, int64_t time)
 650 {
 651         if (type == AVIO_DATA_MARKER_SYNC_POINT || type == AVIO_DATA_MARKER_BOUNDARY_POINT) {
 652                 seen_sync_markers = true;
 653         } else if (type == AVIO_DATA_MARKER_UNKNOWN && !seen_sync_markers) {
 654                 // We don't know if this is a keyframe or not (the muxer could
 655                 // avoid marking it), so we just have to make the best of it.
 656                 type = AVIO_DATA_MARKER_SYNC_POINT;
 657         }
 658
 659         if (type == AVIO_DATA_MARKER_HEADER) {
 660                 stream_mux_header.append((char *)buf, buf_size);
 661                 global_httpd->set_header(HTTPD::MAIN_STREAM, stream_mux_header);
 662         } else {
 663                 global_httpd->add_data(HTTPD::MAIN_STREAM, (char *)buf, buf_size, type == AVIO_DATA_MARKER_SYNC_POINT, time, AVRational{ AV_TIME_BASE, 1 });
 664         }
 665         return buf_size;
 666 }