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

   1 #include "jpeg_frame_view.h"
   2
   3 #include "defs.h"
   4 #include "flags.h"
   5 #include "jpeg_destroyer.h"
   6 #include "jpeglib_error_wrapper.h"
   7 #include "pbo_pool.h"
   8 #include "shared/context.h"
   9 #include "shared/metrics.h"
  10 #include "shared/post_to_main_thread.h"
  11 #include "video_stream.h"
  12 #include "ycbcr_converter.h"
  13
  14 #include <QMouseEvent>
  15 #include <QScreen>
  16 #include <atomic>
  17 #include <chrono>
  18 #include <condition_variable>
  19 #include <deque>
  20 #include <jpeglib.h>
  21 #include <movit/init.h>
  22 #include <movit/resource_pool.h>
  23 #include <movit/util.h>
  24 #include <mutex>
  25 #include <stdint.h>
  26 #include <thread>
  27 #include <unistd.h>
  28 #include <utility>
  29
  30 // Must come after the Qt stuff.
  31 #include "vaapi_jpeg_decoder.h"
  32
  33 using namespace movit;
  34 using namespace std;
  35 using namespace std::chrono;
  36
  37 namespace {
  38
  39 // Just an arbitrary order for std::map.
  40 struct FrameOnDiskLexicalOrder {
  41         bool operator()(const FrameOnDisk &a, const FrameOnDisk &b) const
  42         {
  43                 if (a.pts != b.pts)
  44                         return a.pts < b.pts;
  45                 if (a.offset != b.offset)
  46                         return a.offset < b.offset;
  47                 if (a.filename_idx != b.filename_idx)
  48                         return a.filename_idx < b.filename_idx;
  49                 assert(a.size == b.size);
  50                 return false;
  51         }
  52 };
  53
  54 inline size_t frame_size(const Frame &frame)
  55 {
  56         size_t y_size = frame.width * frame.height;
  57         size_t cbcr_size = y_size / frame.chroma_subsampling_x / frame.chroma_subsampling_y;
  58         return y_size + cbcr_size * 2;
  59 }
  60
  61 struct LRUFrame {
  62         shared_ptr<Frame> frame;
  63         size_t last_used;
  64 };
  65
  66 // There can be multiple JPEGFrameView instances, so make all the metrics static.
  67 once_flag jpeg_metrics_inited;
  68 atomic<int64_t> metric_jpeg_cache_used_bytes{ 0 };  // Same value as cache_bytes_used.
  69 atomic<int64_t> metric_jpeg_cache_limit_bytes{ size_t(CACHE_SIZE_MB) * 1024 * 1024 };
  70 atomic<int64_t> metric_jpeg_cache_given_up_frames{ 0 };
  71 atomic<int64_t> metric_jpeg_cache_hit_frames{ 0 };
  72 atomic<int64_t> metric_jpeg_cache_miss_frames{ 0 };
  73 atomic<int64_t> metric_jpeg_software_decode_frames{ 0 };
  74 atomic<int64_t> metric_jpeg_software_fail_frames{ 0 };
  75 atomic<int64_t> metric_jpeg_vaapi_decode_frames{ 0 };
  76 atomic<int64_t> metric_jpeg_vaapi_fail_frames{ 0 };
  77 atomic<int64_t> metric_jpeg_prepared_frames{ 0 };
  78 atomic<int64_t> metric_jpeg_displayed_frames{ 0 };
  79 Summary metric_jpeg_decode_time_seconds;
  80
  81 }  // namespace
  82
  83 mutex cache_mu;
  84 map<FrameOnDisk, LRUFrame, FrameOnDiskLexicalOrder> cache;  // Under cache_mu.
  85 size_t cache_bytes_used = 0;  // Under cache_mu.
  86 atomic<size_t> event_counter{ 0 };
  87 extern QGLWidget *global_share_widget;
  88 extern atomic<bool> should_quit;
  89
  90 shared_ptr<Frame> decode_jpeg(const string &jpeg)
  91 {
  92         steady_clock::time_point start = steady_clock::now();
  93         shared_ptr<Frame> frame;
  94         if (vaapi_jpeg_decoding_usable) {
  95                 frame = decode_jpeg_vaapi(jpeg);
  96                 if (frame != nullptr) {
  97                         ++metric_jpeg_vaapi_decode_frames;
  98                         steady_clock::time_point stop = steady_clock::now();
  99                         metric_jpeg_decode_time_seconds.count_event(duration<double>(stop - start).count());
 100                         return frame;
 101                 }
 102                 fprintf(stderr, "VA-API hardware decoding failed; falling back to software.\n");
 103                 ++metric_jpeg_vaapi_fail_frames;
 104         }
 105
 106         frame.reset(new Frame);
 107
 108         jpeg_decompress_struct dinfo;
 109         JPEGWrapErrorManager error_mgr(&dinfo);
 110         if (!error_mgr.run([&dinfo] { jpeg_create_decompress(&dinfo); })) {
 111                 return get_black_frame();
 112         }
 113         JPEGDestroyer destroy_dinfo(&dinfo);
 114
 115         if (!error_mgr.run([&dinfo, &jpeg] {
 116                     jpeg_mem_src(&dinfo, reinterpret_cast<const unsigned char *>(jpeg.data()), jpeg.size());
 117                     jpeg_read_header(&dinfo, true);
 118             })) {
 119                 return get_black_frame();
 120         }
 121
 122         jpeg_save_markers(&dinfo, JPEG_APP0 + 1, 0xFFFF);
 123
 124         if (dinfo.num_components != 3) {
 125                 fprintf(stderr, "Not a color JPEG. (%d components, Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
 126                         dinfo.num_components,
 127                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
 128                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
 129                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
 130                 return get_black_frame();
 131         }
 132         if (dinfo.comp_info[0].h_samp_factor != dinfo.max_h_samp_factor ||
 133             dinfo.comp_info[0].v_samp_factor != dinfo.max_v_samp_factor ||  // Y' must not be subsampled.
 134             dinfo.comp_info[1].h_samp_factor != dinfo.comp_info[2].h_samp_factor ||
 135             dinfo.comp_info[1].v_samp_factor != dinfo.comp_info[2].v_samp_factor ||  // Cb and Cr must be identically subsampled.
 136             (dinfo.max_h_samp_factor % dinfo.comp_info[1].h_samp_factor) != 0 ||
 137             (dinfo.max_v_samp_factor % dinfo.comp_info[1].v_samp_factor) != 0) {  // No 2:3 subsampling or other weirdness.
 138                 fprintf(stderr, "Unsupported subsampling scheme. (Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
 139                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
 140                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
 141                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
 142                 abort();
 143         }
 144         dinfo.raw_data_out = true;
 145
 146         if (!error_mgr.run([&dinfo] {
 147                     jpeg_start_decompress(&dinfo);
 148             })) {
 149                 return get_black_frame();
 150         }
 151
 152         frame->width = dinfo.output_width;
 153         frame->height = dinfo.output_height;
 154         frame->chroma_subsampling_x = dinfo.max_h_samp_factor / dinfo.comp_info[1].h_samp_factor;
 155         frame->chroma_subsampling_y = dinfo.max_v_samp_factor / dinfo.comp_info[1].v_samp_factor;
 156
 157         unsigned h_mcu_size = DCTSIZE * dinfo.max_h_samp_factor;
 158         unsigned v_mcu_size = DCTSIZE * dinfo.max_v_samp_factor;
 159         unsigned mcu_width_blocks = (dinfo.output_width + h_mcu_size - 1) / h_mcu_size;
 160         unsigned mcu_height_blocks = (dinfo.output_height + v_mcu_size - 1) / v_mcu_size;
 161
 162         unsigned luma_width_blocks = mcu_width_blocks * dinfo.comp_info[0].h_samp_factor;
 163         unsigned chroma_width_blocks = mcu_width_blocks * dinfo.comp_info[1].h_samp_factor;
 164
 165         PBO pbo = global_pbo_pool->alloc_pbo();
 166         const size_t chroma_width = dinfo.image_width / frame->chroma_subsampling_x;
 167         const size_t chroma_height = dinfo.image_height / frame->chroma_subsampling_y;
 168         size_t cb_offset = dinfo.image_width * dinfo.image_height;
 169         size_t cr_offset = cb_offset + chroma_width * chroma_height;
 170         uint8_t *y_pix = pbo.ptr;
 171         uint8_t *cb_pix = pbo.ptr + cb_offset;
 172         uint8_t *cr_pix = pbo.ptr + cr_offset;
 173         unsigned pitch_y = luma_width_blocks * DCTSIZE;
 174         unsigned pitch_chroma = chroma_width_blocks * DCTSIZE;
 175
 176         if (dinfo.marker_list != nullptr &&
 177             dinfo.marker_list->marker == JPEG_APP0 + 1 &&
 178             dinfo.marker_list->data_length >= 4 &&
 179             memcmp(dinfo.marker_list->data, "Exif", 4) == 0) {
 180                 frame->exif_data.assign(reinterpret_cast<char *>(dinfo.marker_list->data),
 181                         dinfo.marker_list->data_length);
 182         }
 183
 184         if (!error_mgr.run([&dinfo, &y_pix, &cb_pix, &cr_pix, pitch_y, pitch_chroma, v_mcu_size, mcu_height_blocks] {
 185                     JSAMPROW yptr[v_mcu_size], cbptr[v_mcu_size], crptr[v_mcu_size];
 186                     JSAMPARRAY data[3] = { yptr, cbptr, crptr };
 187                     for (unsigned y = 0; y < mcu_height_blocks; ++y) {
 188                             // NOTE: The last elements of cbptr/crptr will be unused for vertically subsampled chroma.
 189                             for (unsigned yy = 0; yy < v_mcu_size; ++yy) {
 190                                     yptr[yy] = y_pix + (y * DCTSIZE * dinfo.max_v_samp_factor + yy) * pitch_y;
 191                                     cbptr[yy] = cb_pix + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * pitch_chroma;
 192                                     crptr[yy] = cr_pix + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * pitch_chroma;
 193                             }
 194
 195                             jpeg_read_raw_data(&dinfo, data, v_mcu_size);
 196                     }
 197
 198                     (void)jpeg_finish_decompress(&dinfo);
 199             })) {
 200                 return get_black_frame();
 201         }
 202
 203         // FIXME: what about resolutions that are not divisible by the block factor?
 204         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo.pbo);
 205         frame->y = create_texture_2d(frame->width, frame->height, GL_R8, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
 206         frame->cb = create_texture_2d(chroma_width, chroma_height, GL_R8, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(cb_offset));
 207         frame->cr = create_texture_2d(chroma_width, chroma_height, GL_R8, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(cr_offset));
 208         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 209
 210         glFlushMappedNamedBufferRange(pbo.pbo, 0, dinfo.image_width * dinfo.image_height + chroma_width * chroma_height * 2);
 211         glMemoryBarrier(GL_PIXEL_BUFFER_BARRIER_BIT);
 212         pbo.upload_done = RefCountedGLsync(GL_SYNC_GPU_COMMANDS_COMPLETE, /*flags=*/0);
 213         frame->uploaded_ui_thread = pbo.upload_done;
 214         frame->uploaded_interpolation = pbo.upload_done;
 215         global_pbo_pool->release_pbo(move(pbo));
 216
 217         ++metric_jpeg_software_decode_frames;
 218         steady_clock::time_point stop = steady_clock::now();
 219         metric_jpeg_decode_time_seconds.count_event(duration<double>(stop - start).count());
 220         return frame;
 221 }
 222
 223 void prune_cache()
 224 {
 225         // Assumes cache_mu is held.
 226         int64_t bytes_still_to_remove = cache_bytes_used - (size_t(CACHE_SIZE_MB) * 1024 * 1024) * 9 / 10;
 227         if (bytes_still_to_remove <= 0)
 228                 return;
 229
 230         vector<pair<size_t, size_t>> lru_timestamps_and_size;
 231         for (const auto &key_and_value : cache) {
 232                 lru_timestamps_and_size.emplace_back(
 233                         key_and_value.second.last_used,
 234                         frame_size(*key_and_value.second.frame));
 235         }
 236         sort(lru_timestamps_and_size.begin(), lru_timestamps_and_size.end());
 237
 238         // Remove the oldest ones until we are below 90% of the cache used.
 239         size_t lru_cutoff_point = 0;
 240         for (const pair<size_t, size_t> &it : lru_timestamps_and_size) {
 241                 lru_cutoff_point = it.first;
 242                 bytes_still_to_remove -= it.second;
 243                 if (bytes_still_to_remove <= 0)
 244                         break;
 245         }
 246
 247         for (auto it = cache.begin(); it != cache.end();) {
 248                 if (it->second.last_used <= lru_cutoff_point) {
 249                         cache_bytes_used -= frame_size(*it->second.frame);
 250                         metric_jpeg_cache_used_bytes = cache_bytes_used;
 251                         it = cache.erase(it);
 252                 } else {
 253                         ++it;
 254                 }
 255         }
 256 }
 257
 258 shared_ptr<Frame> decode_jpeg_with_cache(FrameOnDisk frame_spec, CacheMissBehavior cache_miss_behavior, FrameReader *frame_reader, bool *did_decode)
 259 {
 260         *did_decode = false;
 261         {
 262                 lock_guard<mutex> lock(cache_mu);
 263                 auto it = cache.find(frame_spec);
 264                 if (it != cache.end()) {
 265                         ++metric_jpeg_cache_hit_frames;
 266                         it->second.last_used = event_counter++;
 267                         return it->second.frame;
 268                 }
 269         }
 270
 271         if (cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE) {
 272                 ++metric_jpeg_cache_given_up_frames;
 273                 return nullptr;
 274         }
 275
 276         ++metric_jpeg_cache_miss_frames;
 277
 278         *did_decode = true;
 279         shared_ptr<Frame> frame = decode_jpeg(frame_reader->read_frame(frame_spec, /*read_video=*/true, /*read_audio=*/false).video);
 280
 281         lock_guard<mutex> lock(cache_mu);
 282         cache_bytes_used += frame_size(*frame);
 283         metric_jpeg_cache_used_bytes = cache_bytes_used;
 284         cache[frame_spec] = LRUFrame{ frame, event_counter++ };
 285
 286         if (cache_bytes_used > size_t(CACHE_SIZE_MB) * 1024 * 1024) {
 287                 prune_cache();
 288         }
 289         return frame;
 290 }
 291
 292 void JPEGFrameView::jpeg_decoder_thread_func()
 293 {
 294         size_t num_decoded = 0, num_dropped = 0;
 295
 296         pthread_setname_np(pthread_self(), "JPEGDecoder");
 297         QSurface *surface = create_surface();
 298         QOpenGLContext *context = create_context(surface);
 299         bool ok = make_current(context, surface);
 300         if (!ok) {
 301                 fprintf(stderr, "Video stream couldn't get an OpenGL context\n");
 302                 abort();
 303         }
 304         while (!should_quit.load()) {
 305                 PendingDecode decode;
 306                 CacheMissBehavior cache_miss_behavior = DECODE_IF_NOT_IN_CACHE;
 307                 {
 308                         unique_lock<mutex> lock(cache_mu);  // TODO: Perhaps under another lock?
 309                         any_pending_decodes.wait(lock, [this] {
 310                                 return !pending_decodes.empty() || should_quit.load();
 311                         });
 312                         if (should_quit.load())
 313                                 break;
 314                         decode = pending_decodes.front();
 315                         pending_decodes.pop_front();
 316
 317                         if (pending_decodes.size() > 3) {
 318                                 cache_miss_behavior = RETURN_NULLPTR_IF_NOT_IN_CACHE;
 319                         }
 320                 }
 321
 322                 if (decode.frame != nullptr) {
 323                         // Already decoded, so just show it.
 324                         setDecodedFrame(decode.frame, nullptr, 1.0f);
 325                         continue;
 326                 }
 327
 328                 shared_ptr<Frame> primary_frame, secondary_frame;
 329                 bool drop = false;
 330                 for (int subframe_idx = 0; subframe_idx < 2; ++subframe_idx) {
 331                         const FrameOnDisk &frame_spec = (subframe_idx == 0 ? decode.primary : decode.secondary);
 332                         if (frame_spec.pts == -1) {
 333                                 // No secondary frame.
 334                                 continue;
 335                         }
 336
 337                         bool found_in_cache;
 338                         shared_ptr<Frame> frame = decode_jpeg_with_cache(frame_spec, cache_miss_behavior, &frame_reader, &found_in_cache);
 339
 340                         if (frame == nullptr) {
 341                                 assert(cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE);
 342                                 drop = true;
 343                                 break;
 344                         }
 345
 346                         if (!found_in_cache) {
 347                                 ++num_decoded;
 348                                 if (num_decoded % 1000 == 0) {
 349                                         fprintf(stderr, "Decoded %zu images, dropped %zu (%.2f%% dropped)\n",
 350                                                 num_decoded, num_dropped, (100.0 * num_dropped) / (num_decoded + num_dropped));
 351                                 }
 352                         }
 353                         if (subframe_idx == 0) {
 354                                 primary_frame = std::move(frame);
 355                         } else {
 356                                 secondary_frame = std::move(frame);
 357                         }
 358                 }
 359                 if (drop) {
 360                         ++num_dropped;
 361                         continue;
 362                 }
 363
 364                 // TODO: Could we get jitter between non-interpolated and interpolated frames here?
 365                 setDecodedFrame(primary_frame, secondary_frame, decode.fade_alpha);
 366         }
 367 }
 368
 369 JPEGFrameView::~JPEGFrameView()
 370 {
 371         any_pending_decodes.notify_all();
 372         jpeg_decoder_thread.join();
 373 }
 374
 375 JPEGFrameView::JPEGFrameView(QWidget *parent)
 376         : QGLWidget(parent, global_share_widget)
 377 {
 378         call_once(jpeg_metrics_inited, [] {
 379                 global_metrics.add("jpeg_cache_used_bytes", &metric_jpeg_cache_used_bytes, Metrics::TYPE_GAUGE);
 380                 global_metrics.add("jpeg_cache_limit_bytes", &metric_jpeg_cache_limit_bytes, Metrics::TYPE_GAUGE);
 381                 global_metrics.add("jpeg_cache_frames", { { "action", "given_up" } }, &metric_jpeg_cache_given_up_frames);
 382                 global_metrics.add("jpeg_cache_frames", { { "action", "hit" } }, &metric_jpeg_cache_hit_frames);
 383                 global_metrics.add("jpeg_cache_frames", { { "action", "miss" } }, &metric_jpeg_cache_miss_frames);
 384                 global_metrics.add("jpeg_decode_frames", { { "decoder", "software" }, { "result", "decode" } }, &metric_jpeg_software_decode_frames);
 385                 global_metrics.add("jpeg_decode_frames", { { "decoder", "software" }, { "result", "fail" } }, &metric_jpeg_software_fail_frames);
 386                 global_metrics.add("jpeg_decode_frames", { { "decoder", "vaapi" }, { "result", "decode" } }, &metric_jpeg_vaapi_decode_frames);
 387                 global_metrics.add("jpeg_decode_frames", { { "decoder", "vaapi" }, { "result", "fail" } }, &metric_jpeg_vaapi_fail_frames);
 388                 global_metrics.add("jpeg_frames", { { "action", "prepared" } }, &metric_jpeg_prepared_frames);
 389                 global_metrics.add("jpeg_frames", { { "action", "displayed" } }, &metric_jpeg_displayed_frames);
 390                 vector<double> quantiles{ 0.01, 0.1, 0.25, 0.5, 0.75, 0.9, 0.99 };
 391                 metric_jpeg_decode_time_seconds.init(quantiles, 60.0);
 392                 global_metrics.add("jpeg_decode_time_seconds", &metric_jpeg_decode_time_seconds);
 393         });
 394 }
 395
 396 void JPEGFrameView::setFrame(unsigned stream_idx, FrameOnDisk frame, FrameOnDisk secondary_frame, float fade_alpha)
 397 {
 398         current_stream_idx = stream_idx;  // TODO: Does this interact with fades?
 399
 400         lock_guard<mutex> lock(cache_mu);
 401         PendingDecode decode;
 402         decode.primary = frame;
 403         decode.secondary = secondary_frame;
 404         decode.fade_alpha = fade_alpha;
 405         pending_decodes.push_back(decode);
 406         any_pending_decodes.notify_all();
 407 }
 408
 409 void JPEGFrameView::setFrame(shared_ptr<Frame> frame)
 410 {
 411         lock_guard<mutex> lock(cache_mu);
 412         PendingDecode decode;
 413         decode.frame = std::move(frame);
 414         pending_decodes.push_back(decode);
 415         any_pending_decodes.notify_all();
 416 }
 417
 418 void JPEGFrameView::initializeGL()
 419 {
 420         init_pbo_pool();
 421
 422         glDisable(GL_BLEND);
 423         glDisable(GL_DEPTH_TEST);
 424         check_error();
 425
 426         resource_pool = new ResourcePool;
 427         jpeg_decoder_thread = std::thread(&JPEGFrameView::jpeg_decoder_thread_func, this);
 428
 429         ycbcr_converter.reset(new YCbCrConverter(YCbCrConverter::OUTPUT_TO_RGBA, resource_pool));
 430
 431         ImageFormat inout_format;
 432         inout_format.color_space = COLORSPACE_sRGB;
 433         inout_format.gamma_curve = GAMMA_sRGB;
 434
 435         overlay_chain.reset(new EffectChain(overlay_base_width, overlay_base_height, resource_pool));
 436         overlay_input = (movit::FlatInput *)overlay_chain->add_input(new FlatInput(inout_format, FORMAT_GRAYSCALE, GL_UNSIGNED_BYTE, overlay_base_width, overlay_base_height));
 437
 438         overlay_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 439         overlay_chain->finalize();
 440 }
 441
 442 void JPEGFrameView::resizeGL(int width, int height)
 443 {
 444         check_error();
 445         glViewport(0, 0, width, height);
 446         check_error();
 447
 448         // Save these, as width() and height() will lie with DPI scaling.
 449         gl_width = width;
 450         gl_height = height;
 451 }
 452
 453 void JPEGFrameView::paintGL()
 454 {
 455         glViewport(0, 0, gl_width, gl_height);
 456         if (current_frame == nullptr) {
 457                 glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
 458                 glClear(GL_COLOR_BUFFER_BIT);
 459                 return;
 460         }
 461
 462         if (!displayed_this_frame) {
 463                 ++metric_jpeg_displayed_frames;
 464                 displayed_this_frame = true;
 465         }
 466         if (current_frame->uploaded_ui_thread != nullptr) {
 467                 glWaitSync(current_frame->uploaded_ui_thread.get(), /*flags=*/0, GL_TIMEOUT_IGNORED);
 468                 current_frame->uploaded_ui_thread.reset();
 469         }
 470         if (current_secondary_frame != nullptr && current_secondary_frame->uploaded_ui_thread != nullptr) {
 471                 glWaitSync(current_secondary_frame->uploaded_ui_thread.get(), /*flags=*/0, GL_TIMEOUT_IGNORED);
 472                 current_secondary_frame->uploaded_ui_thread.reset();
 473         }
 474
 475         check_error();
 476         current_chain->render_to_screen();
 477
 478         if (overlay_image != nullptr) {
 479                 if (overlay_input_needs_refresh) {
 480                         overlay_input->set_width(overlay_width);
 481                         overlay_input->set_height(overlay_height);
 482                         overlay_input->set_pixel_data(overlay_image->bits());
 483                         overlay_input_needs_refresh = false;
 484                 }
 485                 glViewport(gl_width - overlay_width, 0, overlay_width, overlay_height);
 486                 overlay_chain->render_to_screen();
 487         }
 488 }
 489
 490 namespace {
 491
 492 }  // namespace
 493
 494 void JPEGFrameView::setDecodedFrame(shared_ptr<Frame> frame, shared_ptr<Frame> secondary_frame, float fade_alpha)
 495 {
 496         post_to_main_thread([this, frame, secondary_frame, fade_alpha] {
 497                 current_frame = frame;
 498                 current_secondary_frame = secondary_frame;
 499
 500                 if (secondary_frame != nullptr) {
 501                         current_chain = ycbcr_converter->prepare_chain_for_fade(frame, secondary_frame, fade_alpha);
 502                 } else {
 503                         current_chain = ycbcr_converter->prepare_chain_for_conversion(frame);
 504                 }
 505                 ++metric_jpeg_prepared_frames;
 506                 displayed_this_frame = false;
 507                 update();
 508         });
 509 }
 510
 511 void JPEGFrameView::mousePressEvent(QMouseEvent *event)
 512 {
 513         if (event->type() == QEvent::MouseButtonPress && event->button() == Qt::LeftButton) {
 514                 emit clicked();
 515         }
 516 }
 517
 518 void JPEGFrameView::set_overlay(const string &text)
 519 {
 520         if (text.empty()) {
 521                 overlay_image.reset();
 522                 return;
 523         }
 524
 525         // Figure out how large the texture needs to be.
 526         {
 527                 QImage img(overlay_width, overlay_height, QImage::Format_Grayscale8);
 528                 QPainter painter(&img);
 529                 QFont font = painter.font();
 530                 font.setPointSize(12);
 531                 QFontMetrics metrics(font);
 532                 overlay_base_width = lrint(metrics.boundingRect(QString::fromStdString(text)).width() + 8.0);
 533                 overlay_base_height = lrint(metrics.height());
 534         }
 535
 536         float dpr = QGuiApplication::primaryScreen()->devicePixelRatio();
 537         overlay_width = lrint(overlay_base_width * dpr);
 538         overlay_height = lrint(overlay_base_height * dpr);
 539
 540         // Work around OpenGL alignment issues.
 541         while (overlay_width % 4 != 0) ++overlay_width;
 542
 543         // Now do the actual drawing.
 544         overlay_image.reset(new QImage(overlay_width, overlay_height, QImage::Format_Grayscale8));
 545         overlay_image->setDevicePixelRatio(dpr);
 546         overlay_image->fill(0);
 547         QPainter painter(overlay_image.get());
 548
 549         painter.setPen(Qt::white);
 550         QFont font = painter.font();
 551         font.setPointSize(12);
 552         painter.setFont(font);
 553
 554         painter.drawText(QRectF(0, 0, overlay_base_width, overlay_base_height), Qt::AlignCenter, QString::fromStdString(text));
 555
 556         // Don't refresh immediately; we might not have an OpenGL context here.
 557         overlay_input_needs_refresh = true;
 558 }
 559
 560 shared_ptr<Frame> get_black_frame()
 561 {
 562         static shared_ptr<Frame> black_frame;
 563         static once_flag flag;
 564         call_once(flag, [] {
 565                 // Not really black, but whatever. :-)
 566                 uint8_t black[] = { 0, 0, 0, 255 };
 567                 RefCountedTexture black_tex = create_texture_2d(1, 1, GL_RGBA8, GL_RGBA, GL_UNSIGNED_BYTE, black);
 568
 569                 black_frame->y = black_tex;
 570                 black_frame->cb = black_tex;
 571                 black_frame->cr = move(black_tex);
 572                 black_frame->width = 1;
 573                 black_frame->height = 1;
 574                 black_frame->chroma_subsampling_x = 1;
 575                 black_frame->chroma_subsampling_y = 1;
 576         });
 577         ++metric_jpeg_software_fail_frames;
 578         return black_frame;
 579 }