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
  20 using namespace movit;
  21 using namespace std;
  22
  23 string filename_for_frame(unsigned stream_idx, int64_t pts);
  24
  25 struct JPEGID {
  26         unsigned stream_idx;
  27         int64_t pts;
  28 };
  29 bool operator< (const JPEGID &a, const JPEGID &b) {
  30         return make_pair(a.stream_idx, a.pts) < make_pair(b.stream_idx, b.pts);
  31 }
  32
  33 struct LRUFrame {
  34         shared_ptr<Frame> frame;
  35         size_t last_used;
  36 };
  37
  38 mutex cache_mu;
  39 map<JPEGID, LRUFrame> cache;  // Under cache_mu.
  40 condition_variable any_pending_decodes;
  41 deque<pair<JPEGID, JPEGFrameView *>> pending_decodes;  // Under cache_mu.
  42 atomic<size_t> event_counter{0};
  43 extern QGLWidget *global_share_widget;
  44
  45 // TODO: Decode using VA-API if available.
  46 shared_ptr<Frame> decode_jpeg(const string &filename)
  47 {
  48         shared_ptr<Frame> frame(new Frame);
  49
  50         jpeg_decompress_struct dinfo;
  51         jpeg_error_mgr jerr;
  52         dinfo.err = jpeg_std_error(&jerr);
  53         jpeg_create_decompress(&dinfo);
  54
  55         FILE *fp = fopen(filename.c_str(), "rb");
  56         if (fp == nullptr) {
  57                 perror(filename.c_str());
  58                 exit(1);
  59         }
  60         jpeg_stdio_src(&dinfo, fp);
  61
  62         jpeg_read_header(&dinfo, true);
  63
  64         if (dinfo.num_components != 3 ||
  65             dinfo.comp_info[0].h_samp_factor != 2 ||
  66             dinfo.comp_info[0].v_samp_factor != 2 ||
  67             dinfo.comp_info[1].h_samp_factor != 1 ||
  68             dinfo.comp_info[1].v_samp_factor != 2 ||
  69             dinfo.comp_info[2].h_samp_factor != 1 ||
  70             dinfo.comp_info[2].v_samp_factor != 2) {
  71                 fprintf(stderr, "Not 4:2:2 JPEG! (%d components, Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
  72                         dinfo.num_components,
  73                         dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
  74                         dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
  75                         dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
  76                 exit(1);
  77         }
  78         dinfo.raw_data_out = true;
  79
  80         jpeg_start_decompress(&dinfo);
  81
  82         frame->width = dinfo.output_width;
  83         frame->height = dinfo.output_height;
  84
  85         unsigned chroma_width_blocks = (dinfo.output_width + 15) / 16;
  86         unsigned width_blocks = chroma_width_blocks * 2;
  87         unsigned height_blocks = (dinfo.output_height + 15) / 16;
  88
  89         // TODO: Decode into a PBO.
  90         frame->y.reset(new uint8_t[width_blocks * (height_blocks * 2) * DCTSIZE2]);
  91         frame->cb.reset(new uint8_t[chroma_width_blocks * (height_blocks * 2) * DCTSIZE2]);
  92         frame->cr.reset(new uint8_t[chroma_width_blocks * (height_blocks * 2) * DCTSIZE2]);
  93
  94         JSAMPROW yptr[16], cbptr[16], crptr[16];
  95         JSAMPARRAY data[3] = { yptr, cbptr, crptr };
  96         for (unsigned y = 0; y < height_blocks; ++y) {
  97                 for (unsigned yy = 0; yy < DCTSIZE * 2; ++yy) {
  98                         yptr[yy] = frame->y.get() + (y * DCTSIZE * 2 + yy) * width_blocks * DCTSIZE;
  99                         cbptr[yy] = frame->cb.get() + (y * DCTSIZE * 2 + yy) * chroma_width_blocks * DCTSIZE;
 100                         crptr[yy] = frame->cr.get() + (y * DCTSIZE * 2 + yy) * chroma_width_blocks * DCTSIZE;
 101                 }
 102
 103                 jpeg_read_raw_data(&dinfo, data, /*num_lines=*/16);
 104         }
 105
 106         (void) jpeg_finish_decompress(&dinfo);
 107         jpeg_destroy_decompress(&dinfo);
 108         fclose(fp);
 109
 110         return frame;
 111 }
 112
 113 void prune_cache()
 114 {
 115         // Assumes cache_mu is held.
 116         vector<size_t> lru_timestamps;
 117         for (const auto &key_and_value : cache) {
 118                 lru_timestamps.push_back(key_and_value.second.last_used);
 119         }
 120
 121         size_t cutoff_point = CACHE_SIZE / 10;  // Prune away the 10% oldest ones.
 122         nth_element(lru_timestamps.begin(), lru_timestamps.begin() + cutoff_point, lru_timestamps.end());
 123         size_t must_be_used_after = lru_timestamps[cutoff_point];
 124         for (auto it = cache.begin(); it != cache.end(); ) {
 125                 if (it->second.last_used < must_be_used_after) {
 126                         it = cache.erase(it);
 127                 } else {
 128                         ++it;
 129                 }
 130         }
 131 }
 132
 133 void jpeg_decoder_thread()
 134 {
 135         size_t num_decoded = 0, num_dropped = 0;
 136
 137         pthread_setname_np(pthread_self(), "JPEGDecoder");
 138         for ( ;; ) {
 139                 JPEGID id;
 140                 JPEGFrameView *dest;
 141                 shared_ptr<Frame> frame;
 142                 {
 143                         unique_lock<mutex> lock(cache_mu);
 144                         any_pending_decodes.wait(lock, [] {
 145                                 return !pending_decodes.empty();
 146                         });
 147                         id = pending_decodes.front().first;
 148                         dest = pending_decodes.front().second;
 149                         pending_decodes.pop_front();
 150
 151                         auto it = cache.find(id);
 152                         if (it != cache.end()) {
 153                                 frame = it->second.frame;
 154                                 it->second.last_used = event_counter++;
 155                         }
 156                 }
 157
 158                 if (frame == nullptr) {
 159                         // Not found in the cache, so we need to do a decode or drop the request.
 160                         // Prune the queue if there are too many pending for this destination.
 161                         // TODO: Could we get starvation here?
 162                         size_t num_pending = 0;
 163                         for (const pair<JPEGID, JPEGFrameView *> &decode : pending_decodes) {
 164                                 if (decode.second == dest) {
 165                                         ++num_pending;
 166                                 }
 167                         }
 168                         if (num_pending > 3) {
 169                                 ++num_dropped;
 170                                 continue;
 171                         }
 172
 173                         frame = decode_jpeg(filename_for_frame(id.stream_idx, id.pts));
 174
 175                         unique_lock<mutex> lock(cache_mu);
 176                         cache[id] = LRUFrame{ frame, event_counter++ };
 177
 178                         if (cache.size() > CACHE_SIZE) {
 179                                 prune_cache();
 180                         }
 181                         ++num_decoded;
 182                         if (num_decoded % 1000 == 0) {
 183                                 fprintf(stderr, "Decoded %zu images, dropped %zu (%.2f%% dropped)\n",
 184                                         num_decoded, num_dropped, (100.0 * num_dropped) / (num_decoded + num_dropped));
 185                         }
 186                 }
 187
 188                 dest->setDecodedFrame(frame);
 189         }
 190 }
 191
 192 JPEGFrameView::JPEGFrameView(QWidget *parent)
 193         : QGLWidget(parent, global_share_widget) {
 194 }
 195
 196 void JPEGFrameView::update_frame()
 197 {
 198         unique_lock<mutex> lock(cache_mu);
 199         pending_decodes.emplace_back(JPEGID{ stream_idx, pts }, this);
 200         any_pending_decodes.notify_all();
 201 }
 202
 203 ResourcePool *resource_pool = nullptr;
 204
 205 void JPEGFrameView::initializeGL()
 206 {
 207         glDisable(GL_BLEND);
 208         glDisable(GL_DEPTH_TEST);
 209         glDepthMask(GL_FALSE);
 210         check_error();
 211
 212         static once_flag once;
 213         call_once(once, [] {
 214                 CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 215                 resource_pool = new ResourcePool;
 216
 217                 std::thread(&jpeg_decoder_thread).detach();
 218         });
 219
 220         chain.reset(new EffectChain(1280, 720, resource_pool));
 221         ImageFormat image_format;
 222         image_format.color_space = COLORSPACE_sRGB;
 223         image_format.gamma_curve = GAMMA_sRGB;
 224         YCbCrFormat ycbcr_format;
 225         ycbcr_format.luma_coefficients = YCBCR_REC_709;
 226         ycbcr_format.full_range = false;
 227         ycbcr_format.num_levels = 256;
 228         ycbcr_format.chroma_subsampling_x = 2;
 229         ycbcr_format.chroma_subsampling_y = 1;
 230         ycbcr_format.cb_x_position = 0.0f;  // H.264 -- _not_ JPEG, even though our input is MJPEG-encoded
 231         ycbcr_format.cb_y_position = 0.5f;  // Irrelevant.
 232         ycbcr_format.cr_x_position = 0.0f;
 233         ycbcr_format.cr_y_position = 0.5f;
 234         ycbcr_input = (movit::YCbCrInput *)chain->add_input(new YCbCrInput(image_format, ycbcr_format, 1280, 720));
 235
 236         ImageFormat inout_format;
 237         inout_format.color_space = COLORSPACE_sRGB;
 238         inout_format.gamma_curve = GAMMA_sRGB;
 239
 240         check_error();
 241         chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 242         check_error();
 243         chain->set_dither_bits(8);
 244         check_error();
 245         chain->finalize();
 246         check_error();
 247 }
 248
 249 void JPEGFrameView::resizeGL(int width, int height)
 250 {
 251         check_error();
 252         glViewport(0, 0, width, height);
 253         check_error();
 254 }
 255
 256 void JPEGFrameView::paintGL()
 257 {
 258         //glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
 259         //glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 260
 261         check_error();
 262         chain->render_to_screen();
 263 }
 264
 265 void JPEGFrameView::setDecodedFrame(std::shared_ptr<Frame> frame)
 266 {
 267         post_to_main_thread([this, frame] {
 268                 current_frame = frame;
 269                 int width_blocks = (frame->width + 15) / 16;
 270                 ycbcr_input->set_width(frame->width);
 271                 ycbcr_input->set_height(frame->height);
 272                 ycbcr_input->set_pixel_data(0, frame->y.get());
 273                 ycbcr_input->set_pixel_data(1, frame->cb.get());
 274                 ycbcr_input->set_pixel_data(2, frame->cr.get());
 275                 ycbcr_input->set_pitch(0, width_blocks * 16);
 276                 ycbcr_input->set_pitch(1, width_blocks * 8);
 277                 ycbcr_input->set_pitch(2, width_blocks * 8);
 278                 update();
 279         });
 280 }