yuvPlayer.cpp

   1 #include<iostream>
   2 #include<fstream>
   3 #include "SDL2/SDL.h"
   4
   5 using namespace std;
   6
   7 /*
   8  * Convert MP4 to YUV
   9  * ffmpeg -i big_buck_bunny_720p_10mb.mp4 -c:v rawvideo -pix_fmt yuv420p out.yuv
  10  *
  11  * Play YUV with ffplay
  12  * ffplay -f rawvideo -pixel_format yuv420p -video_size 1280x720 -i ./out.yuv
  13  *
  14  */
  15
  16 class YuvPlayer
  17 {
  18 public:
  19     YuvPlayer(int width, int height);
  20     void play(string fname);
  21     ~YuvPlayer();
  22
  23 private:
  24     bool readFrame(ifstream& in, uint8_t *raw, size_t size);
  25     void updateRenderer(uint8_t *raw);
  26     string file;
  27     int width = 1280;
  28     int height = 720;
  29     SDL_Window *window;
  30     SDL_Renderer *renderer;
  31     SDL_Texture *texture;
  32 };
  33
  34 YuvPlayer::YuvPlayer(int w, int h)
  35 : width(w)
  36 , height(h)
  37 {
  38     SDL_Init(SDL_INIT_VIDEO);
  39     window = SDL_CreateWindow("YUV Player", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, width, height, SDL_WINDOW_SHOWN);
  40     if (window == nullptr){
  41         cout << "create error: " << SDL_GetError() << endl;
  42     }
  43     renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
  44     texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, width, height);
  45 }
  46
  47 YuvPlayer::~YuvPlayer()
  48 {
  49     SDL_DestroyWindow(window);
  50     SDL_Quit();
  51 }
  52
  53 void YuvPlayer::play(string file)
  54 {
  55     size_t frame_size = width * height * 3 / 2;
  56     uint8_t *raw = (uint8_t *) malloc(sizeof(uint8_t) * frame_size);
  57     ifstream in (file, ios::binary);
  58     if (!in.is_open()) {
  59         cout << "failed to open " << file << endl;
  60     }
  61
  62     SDL_Event event;
  63     bool quit = false;
  64     while(!quit) {
  65         SDL_WaitEvent(&event);
  66         switch(event.type){
  67             case SDL_QUIT:
  68                 quit = true;
  69                 break;
  70             case SDL_KEYDOWN:
  71                 switch(event.key.keysym.sym){
  72                     case SDLK_q:
  73                         quit = true;
  74                         break;
  75                     case SDLK_RIGHT:
  76                         readFrame(in, raw, frame_size);
  77                         updateRenderer(raw);
  78                         break;
  79                     default:
  80                         break;
  81                 }
  82             default:
  83                 break;
  84         }
  85     }
  86     free(raw);
  87 }
  88
  89 bool YuvPlayer::readFrame(ifstream& in, uint8_t *raw, size_t size)
  90 {
  91     in.read(reinterpret_cast<char *>(raw), size);
  92     return true;
  93 }
  94
  95 void YuvPlayer::updateRenderer(uint8_t *raw)
  96 {
  97     SDL_UpdateTexture(texture, nullptr, raw, width * SDL_BYTESPERPIXEL(SDL_PIXELFORMAT_IYUV));
  98     SDL_RenderClear(renderer);
  99     SDL_RenderCopy(renderer, texture, nullptr, nullptr);
 100     SDL_RenderPresent(renderer);
 101 }
 102
 103 int main()
 104 {
 105     string fname = "out.yuv";
 106     YuvPlayer player(1280, 720);
 107     player.play(fname);
 108 }