另外，C99中添加了几个新的头文件，Visual Studio中没有，所以需要你自己下载。并放至相应目录。对于VS2010来说通常是：C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include。
// ffmpeg-example.cpp : Defines the entry point for the console application.
//
//#include "stdafx.h"
#define inline _inline
#ifndef INT64_C
#define INT64_C(c) (c ## LL)
#define UINT64_C(c) (c ## ULL)
#endif
#ifdef __cplusplus
extern "C" {
#endif
#include <libavformat/avformat.h>
#include <libavcodec/avcodec.h>
#include <libswscale/swscale.h>
#ifdef __cplusplus
}
#endif
#include <stdio.h>
static void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame);
int main (int argc, const char * argv[])
{
AVFormatContext *pFormatCtx;
int i, videoStream;
AVCodecContext *pCodecCtx;
AVCodec *pCodec;
AVFrame *pFrame;
AVFrame *pFrameRGB;
AVPacket packet;
int frameFinished;
int numBytes;
uint8_t *buffer;
// Register all formats and codecs
av_register_all();
// Open video file
//if(avformat_open_input(&pFormatCtx, argv[1], NULL, NULL)!=0)
if(avformat_open_input(NULL, argv[1], NULL, NULL)!=0)
return -1; // Couldn‘t open file
// Retrieve stream information
if(av_find_stream_info(pFormatCtx)<0)
return -1; // Couldn‘t find stream information
// Dump information about file onto standard error
av_dump_format(pFormatCtx, 0, argv[1], false);
// Find the first video stream
videoStream=-1;
for(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
pCodecCtx=pFormatCtx->streams[videoStream]->codec;
// Find the decoder for the video stream
pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
if(pCodec==NULL)
return -1; // Codec not found
// Open codec
if(avcodec_open(pCodecCtx, pCodec)<0)
return -1; // Could not open codec
// Hack to correct wrong frame rates that seem to be generated by some codecs
if(pCodecCtx->time_base.num>1000 && pCodecCtx->time_base.den==1)
pCodecCtx->time_base.den=1000;
// Allocate video frame
pFrame=avcodec_alloc_frame();
// Allocate an AVFrame structure
pFrameRGB=avcodec_alloc_frame();
if(pFrameRGB==NULL)
return -1;
// Determine required buffer size and allocate buffer
numBytes=avpicture_get_size(PIX_FMT_RGB24, pCodecCtx->width,
pCodecCtx->height);
//buffer=malloc(numBytes);
buffer=(uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
// Assign appropriate parts of buffer to image planes in pFrameRGB
avpicture_fill((AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24,
pCodecCtx->width, pCodecCtx->height);
// Read frames and save first five frames to disk
i=0;
while(av_read_frame(pFormatCtx, &packet)>=0)
{
// Is this a packet from the video stream?
if(packet.stream_index==videoStream)
{
// Decode video frame
avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
// Did we get a video frame?
if(frameFinished)
{
static struct SwsContext *img_convert_ctx;
#if 0
// Older removed code
// Convert the image from its native format to RGB swscale
img_convert((AVPicture *)pFrameRGB, PIX_FMT_RGB24,
(AVPicture*)pFrame, pCodecCtx->pix_fmt, pCodecCtx->width,
pCodecCtx->height);
// function template, for reference
int sws_scale(struct SwsContext *context, uint8_t* src[], int srcStride[], int srcSliceY,
int srcSliceH, uint8_t* dst[], int dstStride[]);
#endif
// Convert the image into YUV format that SDL uses
if(img_convert_ctx == NULL) {
int w = pCodecCtx->width;
int h = pCodecCtx->height;
img_convert_ctx = sws_getContext(w, h,
pCodecCtx->pix_fmt,
w, h, PIX_FMT_RGB24, SWS_BICUBIC,
NULL, NULL, NULL);
if(img_convert_ctx == NULL) {
fprintf(stderr, "Cannot initialize the conversion context!\n");
exit(1);
}
}
int ret = sws_scale(img_convert_ctx, pFrame->data, pFrame->linesize, 0,
pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
#if 0
// this use to be true, as of 1/2009, but apparently it is no longer true in 3/2009
if(ret) {
fprintf(stderr, "SWS_Scale failed [%d]!\n", ret);
exit(-1);
}
#endif
// Save the frame to disk
if(i++<=5)
SaveFrame(pFrameRGB, pCodecCtx->width, pCodecCtx->height, i);
}
}
// Free the packet that was allocated by av_read_frame
av_free_packet(&packet);
}
// Free the RGB image
//free(buffer);
av_free(buffer);
av_free(pFrameRGB);
// Free the YUV frame
av_free(pFrame);
// Close the codec
avcodec_close(pCodecCtx);
// Close the video file
av_close_input_file(pFormatCtx);
return 0;
}
static void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame)
{
FILE *pFile;
char szFilename[32];
int y;
// Open file
sprintf(szFilename, "frame%d.ppm", iFrame);
pFile=fopen(szFilename, "wb");
if(pFile==NULL)
return;
// Write header
fprintf(pFile, "P6\n%d %d\n255\n", width, height);
// Write pixel data
for(y=0; y<height; y++)
fwrite(pFrame->data[0]+y*pFrame->linesize[0], 1, width*3, pFile);
// Close file
fclose(pFile);
}
2. 设置ffmpeg的lib文件位置
鼠标右键点击工程名，选择属性， 然后选择 配置属性 -> 链接器 -> 常规 -> 附加库目录，添加目录为你下载的32-bit Builds (Dev)中的lib文件目录。
3. 设置ffmpeg的所引用的lib文件
鼠标右键点击工程名，选择属性， 然后选择 配置属性 -> 链接器 -> 输入 -> 附加依赖项，添加的文件为你下载的32-bit Builds (Dev)中的lib文件。
1. 虽然编译通过，但是并不表示就可以运行，当你运行代码时会出现以下错误
原因是，你虽然引用了LIB文件，但这并不是真正的静态库文件，而是对DLL的引用，所以当你调用ffmpeg库函数时，需要DLL文件在场。你可以用dumpbin(VS自带工具)来查看你生成的exe中引用了哪些DLL文件。你在命令行输入：
2. 上段代码中的变量argv[1]，如果你没有指定参数，则会报错。所以如果不指定，则需要将其改为一个const char *的字符串变量，字符串内容为你想读入的视频的全路径，例如
