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         jpeg_save_markers(&dinfo, JPEG_APP0 + 1, 0xFFFF);
 116
 117         if (!error_mgr.run([&dinfo, &jpeg] {
 118                     jpeg_mem_src(&dinfo, reinterpret_cast<const unsigned char *>(jpeg.data()), jpeg.size());
 119                     jpeg_read_header(&dinfo, true);
 120             })) {
 121                 return get_black_frame();
 122         }
 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         glFlush();
 214         frame->uploaded_ui_thread = pbo.upload_done;
 215         frame->uploaded_interpolation = pbo.upload_done;
 216         global_pbo_pool->release_pbo(move(pbo));
 217
 218         ++metric_jpeg_software_decode_frames;
 219         steady_clock::time_point stop = steady_clock::now();
 220         metric_jpeg_decode_time_seconds.count_event(duration<double>(stop - start).count());
 221         return frame;
 222 }
 223
 224 void prune_cache()
 225 {
 226         // Assumes cache_mu is held.
 227         int64_t bytes_still_to_remove = cache_bytes_used - (size_t(CACHE_SIZE_MB) * 1024 * 1024) * 9 / 10;
 228         if (bytes_still_to_remove <= 0)
 229                 return;
 230
 231         vector<pair<size_t, size_t>> lru_timestamps_and_size;
 232         for (const auto &key_and_value : cache) {
 233                 lru_timestamps_and_size.emplace_back(
 234                         key_and_value.second.last_used,
 235                         frame_size(*key_and_value.second.frame));
 236         }
 237         sort(lru_timestamps_and_size.begin(), lru_timestamps_and_size.end());
 238
 239         // Remove the oldest ones until we are below 90% of the cache used.
 240         size_t lru_cutoff_point = 0;
 241         for (const pair<size_t, size_t> &it : lru_timestamps_and_size) {
 242                 lru_cutoff_point = it.first;
 243                 bytes_still_to_remove -= it.second;
 244                 if (bytes_still_to_remove <= 0)
 245                         break;
 246         }
 247
 248         for (auto it = cache.begin(); it != cache.end();) {
 249                 if (it->second.last_used <= lru_cutoff_point) {
 250                         cache_bytes_used -= frame_size(*it->second.frame);
 251                         metric_jpeg_cache_used_bytes = cache_bytes_used;
 252                         it = cache.erase(it);
 253                 } else {
 254                         ++it;
 255                 }
 256         }
 257 }
 258
 259 shared_ptr<Frame> decode_jpeg_with_cache(FrameOnDisk frame_spec, CacheMissBehavior cache_miss_behavior, FrameReader *frame_reader, bool *did_decode)
 260 {
 261         *did_decode = false;
 262         {
 263                 lock_guard<mutex> lock(cache_mu);
 264                 auto it = cache.find(frame_spec);
 265                 if (it != cache.end()) {
 266                         ++metric_jpeg_cache_hit_frames;
 267                         it->second.last_used = event_counter++;
 268                         return it->second.frame;
 269                 }
 270         }
 271
 272         if (cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE) {
 273                 ++metric_jpeg_cache_given_up_frames;
 274                 return nullptr;
 275         }
 276
 277         ++metric_jpeg_cache_miss_frames;
 278
 279         *did_decode = true;
 280         shared_ptr<Frame> frame = decode_jpeg(frame_reader->read_frame(frame_spec, /*read_video=*/true, /*read_audio=*/false).video);
 281
 282         lock_guard<mutex> lock(cache_mu);
 283         cache_bytes_used += frame_size(*frame);
 284         metric_jpeg_cache_used_bytes = cache_bytes_used;
 285         cache[frame_spec] = LRUFrame{ frame, event_counter++ };
 286
 287         if (cache_bytes_used > size_t(CACHE_SIZE_MB) * 1024 * 1024) {
 288                 prune_cache();
 289         }
 290         return frame;
 291 }
 292
 293 void JPEGFrameView::jpeg_decoder_thread_func()
 294 {
 295         size_t num_decoded = 0, num_dropped = 0;
 296
 297         pthread_setname_np(pthread_self(), "JPEGDecoder");
 298         QSurface *surface = create_surface();
 299         QOpenGLContext *context = create_context(surface);
 300         bool ok = make_current(context, surface);
 301         if (!ok) {
 302                 fprintf(stderr, "Video stream couldn't get an OpenGL context\n");
 303                 abort();
 304         }
 305         while (!should_quit.load()) {
 306                 PendingDecode decode;
 307                 CacheMissBehavior cache_miss_behavior = DECODE_IF_NOT_IN_CACHE;
 308                 {
 309                         unique_lock<mutex> lock(cache_mu);  // TODO: Perhaps under another lock?
 310                         any_pending_decodes.wait(lock, [this] {
 311                                 return !pending_decodes.empty() || should_quit.load();
 312                         });
 313                         if (should_quit.load())
 314                                 break;
 315                         decode = pending_decodes.front();
 316                         pending_decodes.pop_front();
 317
 318                         if (pending_decodes.size() > 3) {
 319                                 cache_miss_behavior = RETURN_NULLPTR_IF_NOT_IN_CACHE;
 320                         }
 321                 }
 322
 323                 if (decode.frame != nullptr) {
 324                         // Already decoded, so just show it.
 325                         setDecodedFrame(decode.frame, nullptr, 1.0f);
 326                         continue;
 327                 }
 328
 329                 shared_ptr<Frame> primary_frame, secondary_frame;
 330                 bool drop = false;
 331                 for (int subframe_idx = 0; subframe_idx < 2; ++subframe_idx) {
 332                         const FrameOnDisk &frame_spec = (subframe_idx == 0 ? decode.primary : decode.secondary);
 333                         if (frame_spec.pts == -1) {
 334                                 // No secondary frame.
 335                                 continue;
 336                         }
 337
 338                         bool found_in_cache;
 339                         shared_ptr<Frame> frame = decode_jpeg_with_cache(frame_spec, cache_miss_behavior, &frame_reader, &found_in_cache);
 340
 341                         if (frame == nullptr) {
 342                                 assert(cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE);
 343                                 drop = true;
 344                                 break;
 345                         }
 346
 347                         if (!found_in_cache) {
 348                                 ++num_decoded;
 349                                 if (num_decoded % 1000 == 0) {
 350                                         fprintf(stderr, "Decoded %zu images, dropped %zu (%.2f%% dropped)\n",
 351                                                 num_decoded, num_dropped, (100.0 * num_dropped) / (num_decoded + num_dropped));
 352                                 }
 353                         }
 354                         if (subframe_idx == 0) {
 355                                 primary_frame = std::move(frame);
 356                         } else {
 357                                 secondary_frame = std::move(frame);
 358                         }
 359                 }
 360                 if (drop) {
 361                         ++num_dropped;
 362                         continue;
 363                 }
 364
 365                 // TODO: Could we get jitter between non-interpolated and interpolated frames here?
 366                 setDecodedFrame(primary_frame, secondary_frame, decode.fade_alpha);
 367         }
 368 }
 369
 370 JPEGFrameView::~JPEGFrameView()
 371 {
 372         any_pending_decodes.notify_all();
 373         jpeg_decoder_thread.join();
 374 }
 375
 376 JPEGFrameView::JPEGFrameView(QWidget *parent)
 377         : QGLWidget(parent, global_share_widget)
 378 {
 379         call_once(jpeg_metrics_inited, [] {
 380                 global_metrics.add("jpeg_cache_used_bytes", &metric_jpeg_cache_used_bytes, Metrics::TYPE_GAUGE);
 381                 global_metrics.add("jpeg_cache_limit_bytes", &metric_jpeg_cache_limit_bytes, Metrics::TYPE_GAUGE);
 382                 global_metrics.add("jpeg_cache_frames", { { "action", "given_up" } }, &metric_jpeg_cache_given_up_frames);
 383                 global_metrics.add("jpeg_cache_frames", { { "action", "hit" } }, &metric_jpeg_cache_hit_frames);
 384                 global_metrics.add("jpeg_cache_frames", { { "action", "miss" } }, &metric_jpeg_cache_miss_frames);
 385                 global_metrics.add("jpeg_decode_frames", { { "decoder", "software" }, { "result", "decode" } }, &metric_jpeg_software_decode_frames);
 386                 global_metrics.add("jpeg_decode_frames", { { "decoder", "software" }, { "result", "fail" } }, &metric_jpeg_software_fail_frames);
 387                 global_metrics.add("jpeg_decode_frames", { { "decoder", "vaapi" }, { "result", "decode" } }, &metric_jpeg_vaapi_decode_frames);
 388                 global_metrics.add("jpeg_decode_frames", { { "decoder", "vaapi" }, { "result", "fail" } }, &metric_jpeg_vaapi_fail_frames);
 389                 global_metrics.add("jpeg_frames", { { "action", "prepared" } }, &metric_jpeg_prepared_frames);
 390                 global_metrics.add("jpeg_frames", { { "action", "displayed" } }, &metric_jpeg_displayed_frames);
 391                 vector<double> quantiles{ 0.01, 0.1, 0.25, 0.5, 0.75, 0.9, 0.99 };
 392                 metric_jpeg_decode_time_seconds.init(quantiles, 60.0);
 393                 global_metrics.add("jpeg_decode_time_seconds", &metric_jpeg_decode_time_seconds);
 394         });
 395 }
 396
 397 void JPEGFrameView::setFrame(unsigned stream_idx, FrameOnDisk frame, FrameOnDisk secondary_frame, float fade_alpha)
 398 {
 399         current_stream_idx = stream_idx;  // TODO: Does this interact with fades?
 400
 401         lock_guard<mutex> lock(cache_mu);
 402         PendingDecode decode;
 403         decode.primary = frame;
 404         decode.secondary = secondary_frame;
 405         decode.fade_alpha = fade_alpha;
 406         pending_decodes.push_back(decode);
 407         any_pending_decodes.notify_all();
 408 }
 409
 410 void JPEGFrameView::setFrame(shared_ptr<Frame> frame)
 411 {
 412         lock_guard<mutex> lock(cache_mu);
 413         PendingDecode decode;
 414         decode.frame = std::move(frame);
 415         decode.fade_alpha = 0.0f;
 416         pending_decodes.push_back(decode);
 417         any_pending_decodes.notify_all();
 418 }
 419
 420 void JPEGFrameView::initializeGL()
 421 {
 422         init_pbo_pool();
 423
 424         glDisable(GL_BLEND);
 425         glDisable(GL_DEPTH_TEST);
 426         check_error();
 427
 428         resource_pool = new ResourcePool;
 429         jpeg_decoder_thread = std::thread(&JPEGFrameView::jpeg_decoder_thread_func, this);
 430
 431         ycbcr_converter.reset(new YCbCrConverter(YCbCrConverter::OUTPUT_TO_RGBA, resource_pool));
 432
 433         ImageFormat inout_format;
 434         inout_format.color_space = COLORSPACE_sRGB;
 435         inout_format.gamma_curve = GAMMA_sRGB;
 436
 437         overlay_chain.reset(new EffectChain(overlay_base_width, overlay_base_height, resource_pool));
 438         overlay_input = (movit::FlatInput *)overlay_chain->add_input(new FlatInput(inout_format, FORMAT_GRAYSCALE, GL_UNSIGNED_BYTE, overlay_base_width, overlay_base_height));
 439
 440         overlay_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 441         overlay_chain->finalize();
 442 }
 443
 444 void JPEGFrameView::resizeGL(int width, int height)
 445 {
 446         check_error();
 447         glViewport(0, 0, width, height);
 448         check_error();
 449
 450         // Save these, as width() and height() will lie with DPI scaling.
 451         gl_width = width;
 452         gl_height = height;
 453 }
 454
 455 void JPEGFrameView::paintGL()
 456 {
 457         glViewport(0, 0, gl_width, gl_height);
 458         if (current_frame == nullptr) {
 459                 glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
 460                 glClear(GL_COLOR_BUFFER_BIT);
 461                 return;
 462         }
 463
 464         if (!displayed_this_frame) {
 465                 ++metric_jpeg_displayed_frames;
 466                 displayed_this_frame = true;
 467         }
 468         if (current_frame->uploaded_ui_thread != nullptr) {
 469                 glWaitSync(current_frame->uploaded_ui_thread.get(), /*flags=*/0, GL_TIMEOUT_IGNORED);
 470                 current_frame->uploaded_ui_thread.reset();
 471         }
 472         if (current_secondary_frame != nullptr && current_secondary_frame->uploaded_ui_thread != nullptr) {
 473                 glWaitSync(current_secondary_frame->uploaded_ui_thread.get(), /*flags=*/0, GL_TIMEOUT_IGNORED);
 474                 current_secondary_frame->uploaded_ui_thread.reset();
 475         }
 476
 477         check_error();
 478         current_chain->render_to_screen();
 479
 480         if (overlay_image != nullptr) {
 481                 if (overlay_input_needs_refresh) {
 482                         overlay_input->set_width(overlay_width);
 483                         overlay_input->set_height(overlay_height);
 484                         overlay_input->set_pixel_data(overlay_image->bits());
 485                         overlay_input_needs_refresh = false;
 486                 }
 487                 glViewport(gl_width - overlay_width, 0, overlay_width, overlay_height);
 488                 overlay_chain->render_to_screen();
 489         }
 490 }
 491
 492 namespace {
 493
 494 }  // namespace
 495
 496 void JPEGFrameView::setDecodedFrame(shared_ptr<Frame> frame, shared_ptr<Frame> secondary_frame, float fade_alpha)
 497 {
 498         post_to_main_thread([this, frame, secondary_frame, fade_alpha] {
 499                 current_frame = frame;
 500                 current_secondary_frame = secondary_frame;
 501
 502                 if (secondary_frame != nullptr) {
 503                         current_chain = ycbcr_converter->prepare_chain_for_fade(frame, secondary_frame, fade_alpha);
 504                 } else {
 505                         current_chain = ycbcr_converter->prepare_chain_for_conversion(frame);
 506                 }
 507                 ++metric_jpeg_prepared_frames;
 508                 displayed_this_frame = false;
 509                 update();
 510         });
 511 }
 512
 513 void JPEGFrameView::mousePressEvent(QMouseEvent *event)
 514 {
 515         if (event->type() == QEvent::MouseButtonPress && event->button() == Qt::LeftButton) {
 516                 emit clicked();
 517         }
 518 }
 519
 520 void JPEGFrameView::set_overlay(const string &text)
 521 {
 522         if (text.empty()) {
 523                 overlay_image.reset();
 524                 return;
 525         }
 526
 527         // Figure out how large the texture needs to be.
 528         {
 529                 QImage img(overlay_width, overlay_height, QImage::Format_Grayscale8);
 530                 QPainter painter(&img);
 531                 QFont font = painter.font();
 532                 font.setPointSize(12);
 533                 QFontMetrics metrics(font);
 534                 overlay_base_width = lrint(metrics.boundingRect(QString::fromStdString(text)).width() + 8.0);
 535                 overlay_base_height = lrint(metrics.height());
 536         }
 537
 538         float dpr = QGuiApplication::primaryScreen()->devicePixelRatio();
 539         overlay_width = lrint(overlay_base_width * dpr);
 540         overlay_height = lrint(overlay_base_height * dpr);
 541
 542         // Work around OpenGL alignment issues.
 543         while (overlay_width % 4 != 0) ++overlay_width;
 544
 545         // Now do the actual drawing.
 546         overlay_image.reset(new QImage(overlay_width, overlay_height, QImage::Format_Grayscale8));
 547         overlay_image->setDevicePixelRatio(dpr);
 548         overlay_image->fill(0);
 549         QPainter painter(overlay_image.get());
 550
 551         painter.setPen(Qt::white);
 552         QFont font = painter.font();
 553         font.setPointSize(12);
 554         painter.setFont(font);
 555
 556         painter.drawText(QRectF(0, 0, overlay_base_width, overlay_base_height), Qt::AlignCenter, QString::fromStdString(text));
 557
 558         // Don't refresh immediately; we might not have an OpenGL context here.
 559         overlay_input_needs_refresh = true;
 560 }
 561
 562 shared_ptr<Frame> get_black_frame()
 563 {
 564         static shared_ptr<Frame> black_frame;
 565         static once_flag flag;
 566         call_once(flag, [] {
 567                 // Not really black, but whatever. :-)
 568                 uint8_t black[] = { 0, 0, 0, 255 };
 569                 RefCountedTexture black_tex = create_texture_2d(1, 1, GL_RGBA8, GL_RGBA, GL_UNSIGNED_BYTE, black);
 570
 571                 black_frame->y = black_tex;
 572                 black_frame->cb = black_tex;
 573                 black_frame->cr = move(black_tex);
 574                 black_frame->width = 1;
 575                 black_frame->height = 1;
 576                 black_frame->chroma_subsampling_x = 1;
 577                 black_frame->chroma_subsampling_y = 1;
 578         });
 579         ++metric_jpeg_software_fail_frames;
 580         return black_frame;
 581 }