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
   6 #include <atomic>
   7 #include <condition_variable>
   8 #include <deque>
   9 #include <mutex>
  10 #include <thread>
  11 #include <utility>
  12
  13 #include <movit/resource_pool.h>
  14 #include <movit/init.h>
  15 #include <movit/util.h>
  16
  17 #include "defs.h"
  18 #include "post_to_main_thread.h"
  19 #include "video_stream.h"
  20
  21 using namespace movit;
  22 using namespace std;
  23
  24 bool operator< (const JPEGID &a, const JPEGID &b) {
  25         return make_pair(a.stream_idx, a.pts) < make_pair(b.stream_idx, b.pts);
  26 }
  27
  28 struct LRUFrame {
  29         shared_ptr<Frame> frame;
  30         size_t last_used;
  31 };
  32
  33 mutex cache_mu;
  34 map<JPEGID, LRUFrame> cache;  // Under cache_mu.
  35 condition_variable any_pending_decodes;
  36 deque<pair<JPEGID, JPEGFrameView *>> pending_decodes;  // Under cache_mu.
  37 atomic<size_t> event_counter{0};
  38 extern QGLWidget *global_share_widget;
  39
  40 // TODO: Decode using VA-API if available.
  41 shared_ptr<Frame> decode_jpeg(const string &filename)
  42 {
  43         shared_ptr<Frame> frame(new Frame);
  44
  45         jpeg_decompress_struct dinfo;
  46         jpeg_error_mgr jerr;
  47         dinfo.err = jpeg_std_error(&jerr);
  48         jpeg_create_decompress(&dinfo);
  49
  50         FILE *fp = fopen(filename.c_str(), "rb");
  51         if (fp == nullptr) {
  52                 perror(filename.c_str());
  53                 exit(1);
  54         }
  55         jpeg_stdio_src(&dinfo, fp);
  56
  57         jpeg_read_header(&dinfo, true);
  58
  59         if (dinfo.num_components != 3) {
  60                 fprintf(stderr, "Not a color JPEG. (%d components, Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
  61                         dinfo.num_components,
  62                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
  63                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
  64                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
  65                 exit(1);
  66         }
  67         if (dinfo.comp_info[0].h_samp_factor != dinfo.max_h_samp_factor ||
  68             dinfo.comp_info[0].v_samp_factor != dinfo.max_v_samp_factor ||  // Y' must not be subsampled.
  69             dinfo.comp_info[1].h_samp_factor != dinfo.comp_info[2].h_samp_factor ||
  70             dinfo.comp_info[1].v_samp_factor != dinfo.comp_info[2].v_samp_factor ||  // Cb and Cr must be identically subsampled.
  71             (dinfo.max_h_samp_factor % dinfo.comp_info[1].h_samp_factor) != 0 ||
  72             (dinfo.max_v_samp_factor % dinfo.comp_info[1].v_samp_factor) != 0) {  // No 2:3 subsampling or other weirdness.
  73                 fprintf(stderr, "Unsupported subsampling scheme. (Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
  74                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
  75                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
  76                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
  77                 exit(1);
  78         }
  79         dinfo.raw_data_out = true;
  80
  81         jpeg_start_decompress(&dinfo);
  82
  83         frame->width = dinfo.output_width;
  84         frame->height = dinfo.output_height;
  85         frame->chroma_subsampling_x = dinfo.max_h_samp_factor / dinfo.comp_info[1].h_samp_factor;
  86         frame->chroma_subsampling_y = dinfo.max_v_samp_factor / dinfo.comp_info[1].v_samp_factor;
  87
  88         unsigned h_mcu_size = DCTSIZE * dinfo.max_h_samp_factor;
  89         unsigned v_mcu_size = DCTSIZE * dinfo.max_v_samp_factor;
  90         unsigned mcu_width_blocks = (dinfo.output_width + h_mcu_size - 1) / h_mcu_size;
  91         unsigned mcu_height_blocks = (dinfo.output_height + v_mcu_size - 1) / v_mcu_size;
  92
  93         unsigned luma_width_blocks = mcu_width_blocks * dinfo.comp_info[0].h_samp_factor;
  94         unsigned chroma_width_blocks = mcu_width_blocks * dinfo.comp_info[1].h_samp_factor;
  95         unsigned luma_height_blocks = mcu_height_blocks * dinfo.comp_info[0].v_samp_factor;
  96         unsigned chroma_height_blocks = mcu_height_blocks * dinfo.comp_info[1].v_samp_factor;
  97
  98         // TODO: Decode into a PBO.
  99         frame->y.reset(new uint8_t[luma_width_blocks * luma_height_blocks * DCTSIZE2]);
 100         frame->cb.reset(new uint8_t[chroma_width_blocks * chroma_height_blocks * DCTSIZE2]);
 101         frame->cr.reset(new uint8_t[chroma_width_blocks * chroma_height_blocks * DCTSIZE2]);
 102         frame->pitch_y = luma_width_blocks * DCTSIZE;
 103         frame->pitch_chroma = chroma_width_blocks * DCTSIZE;
 104
 105         JSAMPROW yptr[v_mcu_size], cbptr[v_mcu_size], crptr[v_mcu_size];
 106         JSAMPARRAY data[3] = { yptr, cbptr, crptr };
 107         for (unsigned y = 0; y < mcu_height_blocks; ++y) {
 108                 // NOTE: The last elements of cbptr/crptr will be unused for vertically subsampled chroma.
 109                 for (unsigned yy = 0; yy < v_mcu_size; ++yy) {
 110                         yptr[yy] = frame->y.get() + (y * DCTSIZE * dinfo.max_v_samp_factor + yy) * frame->pitch_y;
 111                         cbptr[yy] = frame->cb.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
 112                         crptr[yy] = frame->cr.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
 113                 }
 114
 115                 jpeg_read_raw_data(&dinfo, data, v_mcu_size);
 116         }
 117
 118         (void) jpeg_finish_decompress(&dinfo);
 119         jpeg_destroy_decompress(&dinfo);
 120         fclose(fp);
 121
 122         return frame;
 123 }
 124
 125 void prune_cache()
 126 {
 127         // Assumes cache_mu is held.
 128         vector<size_t> lru_timestamps;
 129         for (const auto &key_and_value : cache) {
 130                 lru_timestamps.push_back(key_and_value.second.last_used);
 131         }
 132
 133         size_t cutoff_point = CACHE_SIZE / 10;  // Prune away the 10% oldest ones.
 134         nth_element(lru_timestamps.begin(), lru_timestamps.begin() + cutoff_point, lru_timestamps.end());
 135         size_t must_be_used_after = lru_timestamps[cutoff_point];
 136         for (auto it = cache.begin(); it != cache.end(); ) {
 137                 if (it->second.last_used < must_be_used_after) {
 138                         it = cache.erase(it);
 139                 } else {
 140                         ++it;
 141                 }
 142         }
 143 }
 144
 145 shared_ptr<Frame> decode_jpeg_with_cache(JPEGID id, CacheMissBehavior cache_miss_behavior, bool *did_decode)
 146 {
 147         *did_decode = false;
 148         {
 149                 unique_lock<mutex> lock(cache_mu);
 150                 auto it = cache.find(id);
 151                 if (it != cache.end()) {
 152                         it->second.last_used = event_counter++;
 153                         return it->second.frame;
 154                 }
 155         }
 156
 157         if (cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE) {
 158                 return nullptr;
 159         }
 160
 161         *did_decode = true;
 162         shared_ptr<Frame> frame = decode_jpeg(filename_for_frame(id.stream_idx, id.pts));
 163
 164         unique_lock<mutex> lock(cache_mu);
 165         cache[id] = LRUFrame{ frame, event_counter++ };
 166
 167         if (cache.size() > CACHE_SIZE) {
 168                 prune_cache();
 169         }
 170         return frame;
 171 }
 172
 173 void jpeg_decoder_thread()
 174 {
 175         size_t num_decoded = 0, num_dropped = 0;
 176
 177         pthread_setname_np(pthread_self(), "JPEGDecoder");
 178         for ( ;; ) {
 179                 JPEGID id;
 180                 JPEGFrameView *dest;
 181                 CacheMissBehavior cache_miss_behavior = DECODE_IF_NOT_IN_CACHE;
 182                 {
 183                         unique_lock<mutex> lock(cache_mu);  // TODO: Perhaps under another lock?
 184                         any_pending_decodes.wait(lock, [] {
 185                                 return !pending_decodes.empty();
 186                         });
 187                         id = pending_decodes.front().first;
 188                         dest = pending_decodes.front().second;
 189                         pending_decodes.pop_front();
 190
 191                         size_t num_pending = 0;
 192                         for (const pair<JPEGID, JPEGFrameView *> &decode : pending_decodes) {
 193                                 if (decode.second == dest) {
 194                                         ++num_pending;
 195                                 }
 196                         }
 197                         if (num_pending > 3) {
 198                                 cache_miss_behavior = RETURN_NULLPTR_IF_NOT_IN_CACHE;
 199                         }
 200                 }
 201
 202                 bool found_in_cache;
 203                 shared_ptr<Frame> frame = decode_jpeg_with_cache(id, cache_miss_behavior, &found_in_cache);
 204
 205                 if (frame == nullptr) {
 206                         assert(cache_miss_behavior == RETURN_NULLPTR_IF_NOT_IN_CACHE);
 207                         ++num_dropped;
 208                         continue;
 209                 }
 210
 211                 if (!found_in_cache) {
 212                         ++num_decoded;
 213                         if (num_decoded % 1000 == 0) {
 214                                 fprintf(stderr, "Decoded %zu images, dropped %zu (%.2f%% dropped)\n",
 215                                         num_decoded, num_dropped, (100.0 * num_dropped) / (num_decoded + num_dropped));
 216                         }
 217                 }
 218
 219                 dest->setDecodedFrame(frame);
 220         }
 221 }
 222
 223 JPEGFrameView::JPEGFrameView(QWidget *parent)
 224         : QGLWidget(parent, global_share_widget) {
 225 }
 226
 227 void JPEGFrameView::update_frame()
 228 {
 229         unique_lock<mutex> lock(cache_mu);
 230         pending_decodes.emplace_back(JPEGID{ stream_idx, pts }, this);
 231         any_pending_decodes.notify_all();
 232 }
 233
 234 ResourcePool *resource_pool = nullptr;
 235
 236 void JPEGFrameView::initializeGL()
 237 {
 238         glDisable(GL_BLEND);
 239         glDisable(GL_DEPTH_TEST);
 240         check_error();
 241
 242         static once_flag once;
 243         call_once(once, [] {
 244                 resource_pool = new ResourcePool;
 245                 std::thread(&jpeg_decoder_thread).detach();
 246         });
 247
 248         chain.reset(new EffectChain(1280, 720, resource_pool));
 249         ImageFormat image_format;
 250         image_format.color_space = COLORSPACE_sRGB;
 251         image_format.gamma_curve = GAMMA_sRGB;
 252         ycbcr_format.luma_coefficients = YCBCR_REC_709;
 253         ycbcr_format.full_range = false;
 254         ycbcr_format.num_levels = 256;
 255         ycbcr_format.chroma_subsampling_x = 2;
 256         ycbcr_format.chroma_subsampling_y = 1;
 257         ycbcr_format.cb_x_position = 0.0f;  // H.264 -- _not_ JPEG, even though our input is MJPEG-encoded
 258         ycbcr_format.cb_y_position = 0.5f;  // Irrelevant.
 259         ycbcr_format.cr_x_position = 0.0f;
 260         ycbcr_format.cr_y_position = 0.5f;
 261         ycbcr_input = (movit::YCbCrInput *)chain->add_input(new YCbCrInput(image_format, ycbcr_format, 1280, 720));
 262
 263         ImageFormat inout_format;
 264         inout_format.color_space = COLORSPACE_sRGB;
 265         inout_format.gamma_curve = GAMMA_sRGB;
 266
 267         check_error();
 268         chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 269         check_error();
 270         chain->set_dither_bits(8);
 271         check_error();
 272         chain->finalize();
 273         check_error();
 274 }
 275
 276 void JPEGFrameView::resizeGL(int width, int height)
 277 {
 278         check_error();
 279         glViewport(0, 0, width, height);
 280         check_error();
 281 }
 282
 283 void JPEGFrameView::paintGL()
 284 {
 285         if (current_frame == nullptr) {
 286                 glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
 287                 glClear(GL_COLOR_BUFFER_BIT);
 288                 return;
 289         }
 290
 291         check_error();
 292         chain->render_to_screen();
 293 }
 294
 295 void JPEGFrameView::setDecodedFrame(std::shared_ptr<Frame> frame)
 296 {
 297         post_to_main_thread([this, frame] {
 298                 current_frame = frame;
 299                 ycbcr_format.chroma_subsampling_x = frame->chroma_subsampling_x;
 300                 ycbcr_format.chroma_subsampling_y = frame->chroma_subsampling_y;
 301                 ycbcr_input->change_ycbcr_format(ycbcr_format);
 302                 ycbcr_input->set_width(frame->width);
 303                 ycbcr_input->set_height(frame->height);
 304                 ycbcr_input->set_pixel_data(0, frame->y.get());
 305                 ycbcr_input->set_pixel_data(1, frame->cb.get());
 306                 ycbcr_input->set_pixel_data(2, frame->cr.get());
 307                 ycbcr_input->set_pitch(0, frame->pitch_y);
 308                 ycbcr_input->set_pitch(1, frame->pitch_chroma);
 309                 ycbcr_input->set_pitch(2, frame->pitch_chroma);
 310                 update();
 311         });
 312 }