ffmpeg(2)：ffmpeg结合SDL2.0解码视频流
看了http://blog.csdn.net/leixiaohua1020/article/details/8652605后，想学习在windows下面使用ffmpeg库播放视频。
《100行代码实现最简单的基于FFMPEG+SDL的视频播放器》：
该文章里面是使用ffmpeg结合SDL1.2解码视频的。其中用到了SDL_CreateYUVOverlay，SDL_Overlay等函数在SDL2.0已经不存在了。
因此需要想新的办法。
这里需要给自己先补点知识：
SDL（Simple DirectMedia Layer）: 是一套开放源代码的跨平台多媒体开发库，使用C语言写成。SDL提供了数种控制图像、声音、输出入的函数，让开发者只要用相同或是相似的代码就可以开发出跨多个平台（Linux、Windows、Mac OS X等）的应用软件。目前SDL多用于开发游戏、模拟器、媒体播放器等多媒体应用领域。
经过多方的查询，参考了N多资料。解决了。
参考资料：
1. http://blog.csdn.net/ashqal/article/details/17640179
2. http://stackoverflow.com/questions/17579286/sdl2-0-alternative-for-sdl-overlay
3. http://wiki.libsdl.org/MigrationGuide
4. http://blog.csdn.net/leixiaohua1020/article/details/12747899
5. http://blog.csdn.net/leixiaohua1020/article/details/8652605
6. https://github.com/chelyaev/ffmpeg-tutorial
下面的代码，是我自己根据上面帖子里面代码修改的。
#include <stdio.h>
#include <tchar.h>
#include <io.h>
#include <direct.h>
extern "C"
{
// ffmpeg
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libswscale/swscale.h"
// SDL
#include "sdl/SDL.h"
#include "sdl/SDL_thread.h"
};
#pragma comment(lib,"avutil.lib")
#pragma comment(lib,"avcodec.lib")
#pragma comment(lib,"avformat.lib")
#pragma comment(lib,"swscale.lib")
#pragma comment(lib,"sdl2.lib")
int _tmain(int argc, char *argv[])
{
///////////////////////////////////////////////////////////////////////////////
// ffmpeg
// Register all formats and codecs
av_register_all();
// Open video file
AVFormatContext *pFormatCtx = NULL;
const char* filename = "cuc_ieschool.flv";
if( avformat_open_input(&pFormatCtx, filename, NULL, NULL) != 0 ) {
return -1; // Couldn't open file
}
// Retrieve stream information
if( avformat_find_stream_info(pFormatCtx, NULL) < 0 ) {
return -1; // Couldn't find stream information
}
// Dump information about file onto standard error
av_dump_format(pFormatCtx, 0, filename, 0);
// Find the first video stream
int videoStream = -1;
for(int i=0; i < pFormatCtx->nb_streams; i++) {
if( pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO ) {
videoStream = i;
break;
}
}
if( videoStream == -1) {
return -1; // Didn't find a video stream
}
// Get a pointer to the codec context for the video stream
AVCodecContext * pCodecCtx = pFormatCtx->streams[videoStream]->codec;
// Find the decoder for the video stream
AVCodec* pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if( pCodec == NULL ) {
fprintf(stderr, "Unsupported codec!\n");
return -1; // Codec not found
}
// Open codec
AVDictionary* optionsDict = NULL;
if( avcodec_open2(pCodecCtx, pCodec, &optionsDict) < 0 ) {
return -1; // Could not open codec
}
// Allocate video frame
AVFrame* pFrame = av_frame_alloc();
AVFrame* pFrameYUV = av_frame_alloc();
if( pFrameYUV == NULL ) {
return -1;
}
struct SwsContext* sws_ctx = sws_getContext(
pCodecCtx->width,
pCodecCtx->height,
pCodecCtx->pix_fmt,
pCodecCtx->width,
pCodecCtx->height,
PIX_FMT_YUV420P,
SWS_BILINEAR,
NULL,
NULL,
NULL);
int numBytes = avpicture_get_size(
PIX_FMT_YUV420P,
pCodecCtx->width,
pCodecCtx->height);
uint8_t* buffer = (uint8_t *)av_malloc( numBytes*sizeof(uint8_t) );
avpicture_fill((AVPicture *)pFrameYUV, buffer, PIX_FMT_YUV420P,
pCodecCtx->width, pCodecCtx->height);
// Read frames and save first five frames to disk
SDL_Rect sdlRect;
sdlRect.x = 0;
sdlRect.y = 0;
sdlRect.w = pCodecCtx->width;
sdlRect.h = pCodecCtx->height;
//////////////////////////////////////////////////////
// SDL
if( SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER )) {
fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
exit(1);
}
SDL_Window* sdlWindow = SDL_CreateWindow("My Game Window",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
pCodecCtx->width, pCodecCtx->height,
0);
if( !sdlWindow ) {
fprintf(stderr, "SDL: could not set video mode - exiting\n");
exit(1);
}
SDL_Renderer* sdlRenderer = SDL_CreateRenderer(sdlWindow, -1, 0);
SDL_Texture* sdlTexture = SDL_CreateTexture(
sdlRenderer,
SDL_PIXELFORMAT_YV12,
SDL_TEXTUREACCESS_STREAMING,
pCodecCtx->width,
pCodecCtx->height);
AVPacket packet;
SDL_Event event;
while( av_read_frame(pFormatCtx, &packet) >= 0 ) {
// Is this a packet from the video stream?
if( packet.stream_index == videoStream ) {
// Decode video frame
int frameFinished;
avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
// Did we get a video frame?
if( frameFinished ) {
sws_scale(
sws_ctx,
(uint8_t const * const *)pFrame->data,
pFrame->linesize,
0,
pCodecCtx->height,
pFrameYUV->data,
pFrameYUV->linesize
);
SDL_UpdateTexture( sdlTexture, &sdlRect, pFrameYUV->data[0], pFrameYUV->linesize[0] );
SDL_RenderClear( sdlRenderer );
SDL_RenderCopy( sdlRenderer, sdlTexture, &sdlRect, &sdlRect );
SDL_RenderPresent( sdlRenderer );
}
SDL_Delay(50);
}
// Free the packet that was allocated by av_read_frame
av_free_packet(&packet);
SDL_PollEvent(&event);
switch( event.type ) {
case SDL_QUIT:
SDL_Quit();
exit(0);
break;
default:
break;
}
}
SDL_DestroyTexture(sdlTexture);
// Free the YUV frame
av_free(pFrame);
av_free(pFrameYUV);
// Close the codec
avcodec_close(pCodecCtx);
// Close the video file
avformat_close_input(&pFormatCtx);
return 0;
}
PS: 由于写这篇文章的时候，CSDN上传资源有问题，待可以上传的时候，我再上传。
步骤：
1.下载SDL2.0 地址：http://www.libsdl.org/
2.下载ffmpeg在Windows下的SDK 地址：http://ffmpeg.zeranoe.com/builds/
3.下载MinGW // 可以在CSDN下载绿色版 地址：http://download.csdn.net/detail/piano7heart/3651248
下面打算学习如何使用ffmpeg解码音频流。。。