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

   1 #include "jpeg_frame_view.h"
   2
   3 #include <jpeglib.h>
   4 #include <stdint.h>
   5 #include <unistd.h>
   6
   7 #include <atomic>
   8 #include <condition_variable>
   9 #include <deque>
  10 #include <mutex>
  11 #include <thread>
  12 #include <utility>
  13
  14 #include <QMouseEvent>
  15 #include <QScreen>
  16
  17 #include <movit/resource_pool.h>
  18 #include <movit/init.h>
  19 #include <movit/util.h>
  20
  21 #include "defs.h"
  22 #include "post_to_main_thread.h"
  23 #include "video_stream.h"
  24
  25 using namespace movit;
  26 using namespace std;
  27
  28 // Just an arbitrary order for std::map.
  29 struct JPEGIDLexicalOrder
  30 {
  31         bool operator() (const JPEGID &a, const JPEGID &b) const
  32         {
  33                 if (a.stream_idx != b.stream_idx)
  34                         return a.stream_idx < b.stream_idx;
  35                 if (a.pts != b.pts)
  36                         return a.pts < b.pts;
  37                 return a.interpolated < b.interpolated;
  38         }
  39 };
  40
  41 struct LRUFrame {
  42         shared_ptr<Frame> frame;
  43         size_t last_used;
  44 };
  45
  46 mutex cache_mu;
  47 map<JPEGID, LRUFrame, JPEGIDLexicalOrder> cache;  // Under cache_mu.
  48 condition_variable any_pending_decodes, cache_updated;
  49 deque<pair<JPEGID, JPEGFrameView *>> pending_decodes;  // Under cache_mu.
  50 atomic<size_t> event_counter{0};
  51 extern QGLWidget *global_share_widget;
  52
  53 // TODO: Decode using VA-API if available.
  54 shared_ptr<Frame> decode_jpeg(const string &filename)
  55 {
  56         shared_ptr<Frame> frame(new Frame);
  57
  58         jpeg_decompress_struct dinfo;
  59         jpeg_error_mgr jerr;
  60         dinfo.err = jpeg_std_error(&jerr);
  61         jpeg_create_decompress(&dinfo);
  62
  63         FILE *fp = fopen(filename.c_str(), "rb");
  64         if (fp == nullptr) {
  65                 perror(filename.c_str());
  66                 exit(1);
  67         }
  68         jpeg_stdio_src(&dinfo, fp);
  69
  70         jpeg_read_header(&dinfo, true);
  71
  72         if (dinfo.num_components != 3) {
  73                 fprintf(stderr, "Not a color JPEG. (%d components, Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
  74                         dinfo.num_components,
  75                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
  76                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
  77                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
  78                 exit(1);
  79         }
  80         if (dinfo.comp_info[0].h_samp_factor != dinfo.max_h_samp_factor ||
  81             dinfo.comp_info[0].v_samp_factor != dinfo.max_v_samp_factor ||  // Y' must not be subsampled.
  82             dinfo.comp_info[1].h_samp_factor != dinfo.comp_info[2].h_samp_factor ||
  83             dinfo.comp_info[1].v_samp_factor != dinfo.comp_info[2].v_samp_factor ||  // Cb and Cr must be identically subsampled.
  84             (dinfo.max_h_samp_factor % dinfo.comp_info[1].h_samp_factor) != 0 ||
  85             (dinfo.max_v_samp_factor % dinfo.comp_info[1].v_samp_factor) != 0) {  // No 2:3 subsampling or other weirdness.
  86                 fprintf(stderr, "Unsupported subsampling scheme. (Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
  87                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
  88                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
  89                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
  90                 exit(1);
  91         }
  92         dinfo.raw_data_out = true;
  93
  94         jpeg_start_decompress(&dinfo);
  95
  96         frame->width = dinfo.output_width;
  97         frame->height = dinfo.output_height;
  98         frame->chroma_subsampling_x = dinfo.max_h_samp_factor / dinfo.comp_info[1].h_samp_factor;
  99         frame->chroma_subsampling_y = dinfo.max_v_samp_factor / dinfo.comp_info[1].v_samp_factor;
 100
 101         unsigned h_mcu_size = DCTSIZE * dinfo.max_h_samp_factor;
 102         unsigned v_mcu_size = DCTSIZE * dinfo.max_v_samp_factor;
 103         unsigned mcu_width_blocks = (dinfo.output_width + h_mcu_size - 1) / h_mcu_size;
 104         unsigned mcu_height_blocks = (dinfo.output_height + v_mcu_size - 1) / v_mcu_size;
 105
 106         unsigned luma_width_blocks = mcu_width_blocks * dinfo.comp_info[0].h_samp_factor;
 107         unsigned chroma_width_blocks = mcu_width_blocks * dinfo.comp_info[1].h_samp_factor;
 108         unsigned luma_height_blocks = mcu_height_blocks * dinfo.comp_info[0].v_samp_factor;
 109         unsigned chroma_height_blocks = mcu_height_blocks * dinfo.comp_info[1].v_samp_factor;
 110
 111         // TODO: Decode into a PBO.
 112         frame->y.reset(new uint8_t[luma_width_blocks * luma_height_blocks * DCTSIZE2]);
 113         frame->cb.reset(new uint8_t[chroma_width_blocks * chroma_height_blocks * DCTSIZE2]);
 114         frame->cr.reset(new uint8_t[chroma_width_blocks * chroma_height_blocks * DCTSIZE2]);
 115         frame->pitch_y = luma_width_blocks * DCTSIZE;
 116         frame->pitch_chroma = chroma_width_blocks * DCTSIZE;
 117
 118         JSAMPROW yptr[v_mcu_size], cbptr[v_mcu_size], crptr[v_mcu_size];
 119         JSAMPARRAY data[3] = { yptr, cbptr, crptr };
 120         for (unsigned y = 0; y < mcu_height_blocks; ++y) {
 121                 // NOTE: The last elements of cbptr/crptr will be unused for vertically subsampled chroma.
 122                 for (unsigned yy = 0; yy < v_mcu_size; ++yy) {
 123                         yptr[yy] = frame->y.get() + (y * DCTSIZE * dinfo.max_v_samp_factor + yy) * frame->pitch_y;
 124                         cbptr[yy] = frame->cb.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
 125                         crptr[yy] = frame->cr.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
 126                 }
 127
 128                 jpeg_read_raw_data(&dinfo, data, v_mcu_size);
 129         }
 130
 131         (void) jpeg_finish_decompress(&dinfo);
 132         jpeg_destroy_decompress(&dinfo);
 133         fclose(fp);
 134
 135         return frame;
 136 }
 137
 138 void prune_cache()
 139 {
 140         // Assumes cache_mu is held.
 141         vector<size_t> lru_timestamps;
 142         for (const auto &key_and_value : cache) {
 143                 lru_timestamps.push_back(key_and_value.second.last_used);
 144         }
 145
 146         size_t cutoff_point = CACHE_SIZE / 10;  // Prune away the 10% oldest ones.
 147         nth_element(lru_timestamps.begin(), lru_timestamps.begin() + cutoff_point, lru_timestamps.end());
 148         size_t must_be_used_after = lru_timestamps[cutoff_point];
 149         for (auto it = cache.begin(); it != cache.end(); ) {
 150                 if (it->second.last_used < must_be_used_after) {
 151                         it = cache.erase(it);
 152                 } else {
 153                         ++it;
 154                 }
 155         }
 156 }
 157
 158 shared_ptr<Frame> decode_jpeg_with_cache(JPEGID id, CacheMissBehavior cache_miss_behavior, bool *did_decode)
 159 {
 160         *did_decode = false;
 161         {
 162                 unique_lock<mutex> lock(cache_mu);
 163                 auto it = cache.find(id);
 164                 if (it != cache.end()) {
 165                         it->second.last_used = event_counter++;
 166                         return it->second.frame;
 167                 }
 168         }
 169
 170         if (cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE) {
 171                 return nullptr;
 172         }
 173
 174         assert(!id.interpolated);
 175         *did_decode = true;
 176         shared_ptr<Frame> frame = decode_jpeg(filename_for_frame(id.stream_idx, id.pts));
 177
 178         unique_lock<mutex> lock(cache_mu);
 179         cache[id] = LRUFrame{ frame, event_counter++ };
 180
 181         if (cache.size() > CACHE_SIZE) {
 182                 prune_cache();
 183         }
 184         return frame;
 185 }
 186
 187 void jpeg_decoder_thread()
 188 {
 189         size_t num_decoded = 0, num_dropped = 0;
 190
 191         pthread_setname_np(pthread_self(), "JPEGDecoder");
 192         for ( ;; ) {
 193                 JPEGID id;
 194                 JPEGFrameView *dest;
 195                 CacheMissBehavior cache_miss_behavior = DECODE_IF_NOT_IN_CACHE;
 196                 {
 197                         unique_lock<mutex> lock(cache_mu);  // TODO: Perhaps under another lock?
 198                         any_pending_decodes.wait(lock, [] {
 199                                 return !pending_decodes.empty();
 200                         });
 201                         id = pending_decodes.front().first;
 202                         dest = pending_decodes.front().second;
 203                         pending_decodes.pop_front();
 204
 205                         size_t num_pending = 0;
 206                         for (const pair<JPEGID, JPEGFrameView *> &decode : pending_decodes) {
 207                                 if (decode.second == dest) {
 208                                         ++num_pending;
 209                                 }
 210                         }
 211                         if (num_pending > 3) {
 212                                 cache_miss_behavior = RETURN_NULLPTR_IF_NOT_IN_CACHE;
 213                         }
 214                 }
 215
 216                 bool found_in_cache;
 217                 shared_ptr<Frame> frame;
 218                 if (id.interpolated) {
 219                         // Interpolated frames are never decoded by us,
 220                         // put directly into the cache from VideoStream.
 221                         unique_lock<mutex> lock(cache_mu);
 222                         cache_updated.wait(lock, [id] {
 223                                 return cache.count(id) != 0;
 224                         });
 225                         found_in_cache = true;  // Don't count it as a decode.
 226
 227                         auto it = cache.find(id);
 228                         assert(it != cache.end());
 229
 230                         it->second.last_used = event_counter++;
 231                         frame = it->second.frame;
 232                         if (frame == nullptr) {
 233                                 // We inserted a nullptr as signal that the frame was never
 234                                 // interpolated and that we should stop waiting.
 235                                 // But don't let it linger in the cache anymore.
 236                                 cache.erase(it);
 237                         }
 238                 } else {
 239                         frame = decode_jpeg_with_cache(id, cache_miss_behavior, &found_in_cache);
 240                 }
 241
 242                 if (frame == nullptr) {
 243                         assert(id.interpolated || cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE);
 244                         ++num_dropped;
 245                         continue;
 246                 }
 247
 248                 if (!found_in_cache) {
 249                         ++num_decoded;
 250                         if (num_decoded % 1000 == 0) {
 251                                 fprintf(stderr, "Decoded %zu images, dropped %zu (%.2f%% dropped)\n",
 252                                         num_decoded, num_dropped, (100.0 * num_dropped) / (num_decoded + num_dropped));
 253                         }
 254                 }
 255
 256                 // TODO: Could we get jitter between non-interpolated and interpolated frames here?
 257                 dest->setDecodedFrame(frame);
 258         }
 259 }
 260
 261 JPEGFrameView::JPEGFrameView(QWidget *parent)
 262         : QGLWidget(parent, global_share_widget) {
 263 }
 264
 265 void JPEGFrameView::setFrame(unsigned stream_idx, int64_t pts, bool interpolated)
 266 {
 267         current_stream_idx = stream_idx;
 268
 269         unique_lock<mutex> lock(cache_mu);
 270         pending_decodes.emplace_back(JPEGID{ stream_idx, pts, interpolated }, this);
 271         any_pending_decodes.notify_all();
 272 }
 273
 274 void JPEGFrameView::insert_interpolated_frame(unsigned stream_idx, int64_t pts, shared_ptr<Frame> frame)
 275 {
 276         JPEGID id{ stream_idx, pts, true };
 277
 278         // We rely on the frame not being evicted from the cache before
 279         // jpeg_decoder_thread() sees it and can display it (otherwise,
 280         // that thread would hang). With a default cache of 1000 elements,
 281         // that would sound like a reasonable assumption.
 282         unique_lock<mutex> lock(cache_mu);
 283         cache[id] = LRUFrame{ std::move(frame), event_counter++ };
 284         cache_updated.notify_all();
 285 }
 286
 287 ResourcePool *resource_pool = nullptr;
 288
 289 void JPEGFrameView::initializeGL()
 290 {
 291         glDisable(GL_BLEND);
 292         glDisable(GL_DEPTH_TEST);
 293         check_error();
 294
 295         static once_flag once;
 296         call_once(once, [] {
 297                 resource_pool = new ResourcePool;
 298                 std::thread(&jpeg_decoder_thread).detach();
 299         });
 300
 301         chain.reset(new EffectChain(1280, 720, resource_pool));
 302         ImageFormat image_format;
 303         image_format.color_space = COLORSPACE_sRGB;
 304         image_format.gamma_curve = GAMMA_sRGB;
 305         ycbcr_format.luma_coefficients = YCBCR_REC_709;
 306         ycbcr_format.full_range = false;
 307         ycbcr_format.num_levels = 256;
 308         ycbcr_format.chroma_subsampling_x = 2;
 309         ycbcr_format.chroma_subsampling_y = 1;
 310         ycbcr_format.cb_x_position = 0.0f;  // H.264 -- _not_ JPEG, even though our input is MJPEG-encoded
 311         ycbcr_format.cb_y_position = 0.5f;  // Irrelevant.
 312         ycbcr_format.cr_x_position = 0.0f;
 313         ycbcr_format.cr_y_position = 0.5f;
 314         ycbcr_input = (movit::YCbCrInput *)chain->add_input(new YCbCrInput(image_format, ycbcr_format, 1280, 720));
 315
 316         ImageFormat inout_format;
 317         inout_format.color_space = COLORSPACE_sRGB;
 318         inout_format.gamma_curve = GAMMA_sRGB;
 319
 320         check_error();
 321         chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 322         check_error();
 323         chain->set_dither_bits(8);
 324         check_error();
 325         chain->finalize();
 326         check_error();
 327
 328         overlay_chain.reset(new EffectChain(overlay_base_width, overlay_base_height, resource_pool));
 329         overlay_input = (movit::FlatInput *)overlay_chain->add_input(new FlatInput(image_format, FORMAT_GRAYSCALE, GL_UNSIGNED_BYTE, overlay_base_width, overlay_base_height));
 330
 331         overlay_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 332         overlay_chain->finalize();
 333 }
 334
 335 void JPEGFrameView::resizeGL(int width, int height)
 336 {
 337         check_error();
 338         glViewport(0, 0, width, height);
 339         check_error();
 340
 341         // Save these, as width() and height() will lie with DPI scaling.
 342         gl_width = width;
 343         gl_height = height;
 344 }
 345
 346 void JPEGFrameView::paintGL()
 347 {
 348         glViewport(0, 0, gl_width, gl_height);
 349         if (current_frame == nullptr) {
 350                 glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
 351                 glClear(GL_COLOR_BUFFER_BIT);
 352                 return;
 353         }
 354
 355         check_error();
 356         chain->render_to_screen();
 357
 358         if (overlay_image != nullptr) {
 359                 if (overlay_input_needs_refresh) {
 360                         overlay_input->set_width(overlay_width);
 361                         overlay_input->set_height(overlay_height);
 362                         overlay_input->set_pixel_data(overlay_image->bits());
 363                 }
 364                 glViewport(gl_width - overlay_width, 0, overlay_width, overlay_height);
 365                 overlay_chain->render_to_screen();
 366         }
 367 }
 368
 369 void JPEGFrameView::setDecodedFrame(std::shared_ptr<Frame> frame)
 370 {
 371         post_to_main_thread([this, frame] {
 372                 current_frame = frame;
 373                 ycbcr_format.chroma_subsampling_x = frame->chroma_subsampling_x;
 374                 ycbcr_format.chroma_subsampling_y = frame->chroma_subsampling_y;
 375                 ycbcr_input->change_ycbcr_format(ycbcr_format);
 376                 ycbcr_input->set_width(frame->width);
 377                 ycbcr_input->set_height(frame->height);
 378                 ycbcr_input->set_pixel_data(0, frame->y.get());
 379                 ycbcr_input->set_pixel_data(1, frame->cb.get());
 380                 ycbcr_input->set_pixel_data(2, frame->cr.get());
 381                 ycbcr_input->set_pitch(0, frame->pitch_y);
 382                 ycbcr_input->set_pitch(1, frame->pitch_chroma);
 383                 ycbcr_input->set_pitch(2, frame->pitch_chroma);
 384                 update();
 385         });
 386 }
 387
 388 void JPEGFrameView::mousePressEvent(QMouseEvent *event)
 389 {
 390         if (event->type() == QEvent::MouseButtonPress && event->button() == Qt::LeftButton) {
 391                 emit clicked();
 392         }
 393 }
 394
 395 void JPEGFrameView::set_overlay(const string &text)
 396 {
 397         if (text.empty()) {
 398                 overlay_image.reset();
 399                 return;
 400         }
 401
 402         float dpr = QGuiApplication::primaryScreen()->devicePixelRatio();
 403         overlay_width = lrint(overlay_base_width * dpr);
 404         overlay_height = lrint(overlay_base_height * dpr);
 405
 406         overlay_image.reset(new QImage(overlay_width, overlay_height, QImage::Format_Grayscale8));
 407         overlay_image->setDevicePixelRatio(dpr);
 408         overlay_image->fill(0);
 409         QPainter painter(overlay_image.get());
 410
 411         painter.setPen(Qt::white);
 412         QFont font = painter.font();
 413         font.setPointSize(12);
 414         painter.setFont(font);
 415
 416         painter.drawText(QRectF(0, 0, overlay_base_width, overlay_base_height), Qt::AlignCenter, QString::fromStdString(text));
 417
 418         // Don't refresh immediately; we might not have an OpenGL context here.
 419         overlay_input_needs_refresh = true;
 420 }