花了好几天的时间，终于把这东东搞出来了
sdl2相比sdl1，api有了比较大的变化，尤其是绘图方面
网上基本上找不到用sdl2编写的，只好自己不断探索尝试
ffmpeg和sdl都可以直接去官网下载，现在已经有编译好的vc库文件下载，怎么配置网上有很多，这里就不多说了
推荐几个sdl2的教程：
http://adolfans.github.io/sdltutorialcn/blog/2013/01/25/sdl-2-dot-0-tutorial-index/
http://www.sdltutorials.com/tutorials
ffmpeg的api文档可以在这里看：
http://ffmpeg.org/doxygen/2.0/index.html
需要注意的一点是，建立工程的时候最好选择 控制台应用程序，加上预编译头文件，即有stdafx.h头文件的那种
再推荐一个学习的博客，我的代码就是参考他的写出来的
http://blog.csdn.net/leixiaohua1020/article/details/8652605
还有一个很好的教程，虽然有点过时，但是基本思想是不变的，很值得参考
最后你需要了解一下像素格式，可以参考：
在sdl的头文件SDL_Pixel.h中有各种像素格式的声明
其他不多说了，直接上代码
#include "stdafx.h"
extern "C"{
#include "libavcodec\avcodec.h"
#include "libavformat\avformat.h"
#include "libswscale\swscale.h"
}
#include "SDL.h"
#include "SDL_image.h"
#include "SDL_thread.h"
#include <iostream>
using namespace std;
/*
void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame){
FILE *pFile;
char szFilename[32];
int y;
sprintf(szFilename, "frame%d.ppm", iFrame);
pFile = fopen(szFilename, "wb");
if (pFile == NULL){
cout << "open file:" << szFilename << " error." << endl;
return;
}
//Write header
}*/
int _tmain(int argc, char *agrv[]){
av_register_all(); //注册了所有的文件格式和编解码的库，它们将被自动的使用在被打开的合适格式的文件上
AVFormatContext *pFormatCtx;
pFormatCtx = avformat_alloc_context();
char filepath[] = "../../resource/test.mp4";
//Open an input stream and read the header
if (avformat_open_input(&pFormatCtx, filepath, NULL, NULL) != 0){
printf("Can‘t open the file\n");
return -1;
}
//Retrieve stream information
if (avformat_find_stream_info(pFormatCtx, NULL) < 0){
printf("Couldn‘t find stream information.\n");
return -1;
}
int i, videoIndex;
AVCodecContext *pCodecCtx;
AVCodec *pCodec;
//Find the first video stream
videoIndex = -1;
for (i = 0; i < pFormatCtx->nb_streams; i++){//视音频流的个数
if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO){
videoIndex = i;
break;
}
}
if (videoIndex == -1)
return -1;
//Get a pointer to the codec context for the video stream
//流中关于编解码器的信息就是被我们叫做"codec context"（编解码器上下文）
//的东西。这里面包含了流中所使用的关于编解码器的所有信
pCodecCtx = pFormatCtx->streams[videoIndex]->codec;
//Find the decoder for the video stream
pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if (pCodec == NULL){
printf("Unsupported codec!\n");
return -1;
}
//Open codec
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0){
printf("Could not open codec.\n");
return -1;
}
//allocate video frame and set its fileds to default value
AVFrame *pFrame, *pFrameYUV;
pFrame = av_frame_alloc();
pFrameYUV = av_frame_alloc();
//即使我们申请了一帧的内存，当转换的时候，我们仍然需要一个地方来放置原始
//的数据。我们使用avpicture_get_size 来获得我们需要的大小， 然后手工申请
//内存空间：
uint8_t *out_buffer;
int numBytes;
numBytes = avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
//av_malloc 是ffmpeg 的malloc，用来实现一个简单的malloc 的包装，这样来保
//证内存地址是对齐的（4 字节对齐或者2 字节对齐）。它并不能保 护你不被内
//存泄漏，重复释放或者其它malloc 的问题所困扰。
out_buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
//Assign appropriate parts of buffer to image planes in pFrameYUV
//Note that pFrameYUV is an AVFrame, but AVFrame is a superset of AVPicture
avpicture_fill((AVPicture*)pFrameYUV, out_buffer, PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
//----------------SDL--------------------------------------//
if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)){
printf("Could not initialize SDL -%s\n", SDL_GetError());
exit(1);
}
SDL_Window *window = nullptr;
window = SDL_CreateWindow("MyPlayer", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
pCodecCtx->width, pCodecCtx->height, SDL_WINDOW_SHOWN);
if (!window){
cout << SDL_GetError() << endl;
return 1;
}
SDL_Renderer *ren = nullptr;
ren = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
if (ren == nullptr){
cout << SDL_GetError() << endl;
return -1;
}
SDL_Texture *texture = nullptr;
texture = SDL_CreateTexture(ren, SDL_PIXELFORMAT_YV12,
SDL_TEXTUREACCESS_STREAMING, pCodecCtx->width, pCodecCtx->height);
SDL_Rect rect;
rect.x = 0, rect.y = 0;
rect.w = pCodecCtx->width;
rect.h = pCodecCtx->height;
//*************************************************************//
//通过读取包来读取整个视频流，然后把它解码成帧，最后转换格式并且保存
int frameFinished;
//int psize = pCodecCtx->width * pCodecCtx->height;
AVPacket packet;
av_new_packet(&packet, numBytes);
//output file information
cout << "文件信息----------------------------------" << endl;
av_dump_format(pFormatCtx, 0, filepath, 0);
cout << "--------------------------------------------" << endl;
i = 0;
int ret;
static struct SwsContext *img_convert_ctx;
img_convert_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height,
pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height, PIX_FMT_YUV420P,
SWS_BICUBIC, NULL, NULL, NULL);
//Read the next frame of a stream
while (av_read_frame(pFormatCtx, &packet) >= 0){
//Is this a packet from the video stream?
if (packet.stream_index == videoIndex){
//decode video frame of size packet.size from packet.data into picture
ret = avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
//Did we get a video frame?
if (ret >= 0){
//Convert the image from its native format to YUV
if (frameFinished){
sws_scale(img_convert_ctx, (const uint8_t* const*)pFrame->data,
pFrame->linesize, 0, pCodecCtx->height, pFrameYUV->data, pFrameYUV->linesize);
SDL_UpdateYUVTexture(texture, &rect, pFrameYUV->data[0], pFrameYUV->linesize[0],
pFrameYUV->data[1], pFrameYUV->linesize[1], pFrameYUV->data[2], pFrameYUV->linesize[2]);
SDL_RenderClear(ren);
SDL_RenderCopy(ren, texture, &rect, &rect);
SDL_RenderPresent(ren);
}
SDL_Delay(50);
}
else{
cout << "decode error" << endl;
return -1;
}
}
}
av_free_packet(&packet);
SDL_Event event;
SDL_PollEvent(&event);
switch (event.type){
case SDL_QUIT:
SDL_Quit();
exit(0);
break;
default:
break;
}
SDL_DestroyTexture(texture);
av_frame_free(&pFrame);
av_frame_free(&pFrameYUV);
avcodec_close(pCodecCtx);
avformat_close_input(&pFormatCtx);
return 0;
}
ffmpeg+sdl2.0编写最简单的视频播放器,布布扣,bubuko.com
原文：http://blog.csdn.net/jiqiujia/article/details/20547231