12 * ffmpeg -i big_buck_bunny_720p_10mb.mp4 -c:v rawvideo -pix_fmt yuv420p out.yuv
14 * Play YUV with ffplay
15 * ffplay -f rawvideo -pixel_format yuv420p -video_size 1280x720 -i ./out.yuv
18 * 1. press 'P' to pause or play as the given framerate
19 * 2. press 'q' to quit
20 * 3. press RIGHT to next frame, LEFT to previous frame
21 * 4. color space transform
27 YuvPlayer(int width, int height, const string& title = "YUV Player");
28 void play(string fname, int fps = -1);
33 bool readFrame(ifstream& in, uint8_t *raw, size_t size);
34 void updateRenderer(uint8_t *raw);
39 SDL_Renderer *renderer;
41 unsigned int frameCnt = 0;
43 ifstream::pos_type last_pos;
44 bool isShowingGrid = false;
49 class ImageOperation {
51 ImageOperation(uint8_t *r, int width, int height);
60 YuvPlayer::YuvPlayer(int w, int h, const string& t)
65 SDL_Init(SDL_INIT_VIDEO);
66 window = SDL_CreateWindow(title.c_str(), SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, width, height, SDL_WINDOW_SHOWN);
67 if (window == nullptr){
68 cout << "create error: " << SDL_GetError() << endl;
70 renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
71 texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, width, height);
74 YuvPlayer::~YuvPlayer()
76 SDL_DestroyTexture(texture);
77 SDL_DestroyRenderer(renderer);
78 SDL_DestroyWindow(window);
82 void YuvPlayer::play(string file, int fps)
84 size_t frame_size = width * height * 3 / 2;
85 raw = (uint8_t *) malloc(sizeof(uint8_t) * frame_size);
86 ifstream in (file, ios::binary);
88 cout << "failed to open " << file << endl;
94 bool isPlaying = true;
95 int interval = 1000 / fps;
98 interval = isPlaying ? 1000 / fps : -1;
99 SDL_WaitEventTimeout(&event, interval);
100 if(fps > 0 && isPlaying){
101 if(readFrame(in, raw, frame_size)){
110 switch(event.key.keysym.sym){
115 if(readFrame(in, raw, frame_size)){
120 frameCnt = frameCnt >= 2 ? frameCnt - 2 : 0;
121 in.seekg(frameCnt * frame_size);
122 if(readFrame(in, raw, frame_size)){
128 isPlaying = !isPlaying;
143 void YuvPlayer::toggleGrid()
145 isShowingGrid = !isShowingGrid;
150 bool YuvPlayer::readFrame(ifstream& in, uint8_t *raw, size_t size)
152 last_pos = in.tellg();
153 bool ret = (bool) in.read(reinterpret_cast<char *>(raw), size);
157 ss << this->title << " [" << setw(4) << to_string(frameCnt) << "]";
158 SDL_SetWindowTitle(window, ss.str().c_str());
160 cout << "read error" << endl;
165 void YuvPlayer::updateRenderer(uint8_t *raw)
167 SDL_UpdateTexture(texture, nullptr, raw, width * SDL_BYTESPERPIXEL(SDL_PIXELFORMAT_IYUV));
168 SDL_RenderClear(renderer);
169 SDL_RenderCopy(renderer, texture, nullptr, nullptr);
172 SDL_SetRenderDrawColor( renderer, 0x00, 0x00, 0xFF, 0xFF );
173 //SDL_RenderDrawLine( renderer, 0, height / 2, width, height / 2 );
174 SDL_RenderDrawLine( renderer, 0, height / 3, width, height / 3 );
175 SDL_RenderDrawLine( renderer, 0, height * 2 / 3, width, height * 2 / 3 );
177 SDL_RenderDrawLine( renderer, width / 3, 0, width / 3, height );
178 SDL_RenderDrawLine( renderer, width * 2 / 3, 0, width * 2 / 3, height );
182 SDL_RenderPresent(renderer);
185 int main(int argc, char* argv[])
187 string fname = "out.yuv";
188 YuvPlayer player(1280, 720);
189 player.play(fname, 25);
190 //player.play(fname);