本文转载自：/article/p-vxdntdgc-bkq.html
由于个人是从事音视频开发相关的工作，所以也把自己的一些过程写下来，方便大家以及自己查看，时间关系就不多瞎说了，具体过程，都是图文教程
在搭建开发环境之前，首先需要下载ffmpeg源码 (dev版本+share版本) 提醒下 ffmpeg 源码应该是 32bit, 因为当前新建工程也是32位 注意头文件的引用
main函数代码如下: int main (int argc, char **argv) { AVFormatContext *fmt_ctx = NULL; AVDictionaryEntry *tag = NULL; int ret; av_register_all(); if ((ret = avformat_open_input(&fmt_ctx, "love.mp4", NULL, NULL))) return ret; while ((tag = av_dict_get(fmt_ctx->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) { printf("%s=%s\n", tag->key, tag->value); } //运行结果为打印音视频媒体文件基本信息 avformat_close_input(&fmt_ctx); return 0; } 运行结果截图:提醒：VS安装目录:E:\software_setup\VS\VC\include 需要添加两个头文件stdint.h 和inttypes.h
遇到问题：
1.编译失败，
Error 1 error LNK: unresolved external symbol _av_register_all referenced in function _wmain C:\Users\Andres\Documents\Visual Studio \Projects\PruebaFFMPEG\PruebaFFMPEG\PruebaFFMPEG.obj PruebaFFMPEG
除了要查明c++引用C文件的文件名有变化失败，还要检查
0down voteaccepted
Open Project properties -> click Configuration Manager... -> Active Solution Platform -> New.. -> Select x64 (see screenshotgoo.gl/54ND5t)–pogorskiy
2.缺少的头文件
Ffmpeg使用的是C99，但是vs不支持c99。在VS编译ffmpeg时会用到的两个C99标准的头文件。，所以需要你自己下载。并放至相应目录。对于VS来说通常是：C:\ProgramFiles (x86)\Microsoft Visual Studio10.0\VC\include。下载地址：/detail/mfcai_blog/9540995
在cpp文件里调用ffmpeg函数要注意.extern“C”是使C++能够调用C写的库文件的一种方式。如果在c++代码中要使用C库中的函数的话，那么就要使用extern”C”来说明。
一个用C写成的库如果想被C/C++同时可以使用，那在头文件应该加上
#ifdef__cplusplus
extern "C"{
#endif
#ifdef__cplusplus
} // endof extern"C"
#endif
3.
VS下配置SDL开发环境：
1.下载SDL-devel-1.2.15-VC.zip（在/download-1.2.php可见）
2.解压缩SDL-devel-1.2.13-VC8.zip，docs里面包含了官方文档，这将是你学习SDL的主要参考资料。找到你在硬盘上安装VC的位置，类似：C:\Program Files\Microsoft Visual Studio 9.0\VC，打开include文件夹，在里面建立一个新文件夹，取名为SDL，打开这个新的文件夹：C:\Program Files\Microsoft Visual Studio 9.0\VC\include\SDL，然后，将SDL Development Libraries中include文件夹里面的文件全部拷贝到刚才建立起来的那个新文件夹中。
然后，回到VC的.\VC文件夹下，打开lib文件夹：C:\Program Files\Microsoft Visual Studio 9.0\VC\lib，将SDL Development Libraries中lib文件夹下的SDL.lib和SDLmain.lib两个文件拷贝到刚才的那个VC的lib文件夹下
（注意库可以这么取，但是位置不要这么放，要像上面放置ffmpeg库那样去配置）
4.代码示例
#include <stdafx.h> #include <stdio.h> #define __STDC_CONSTANT_MACROS extern "C" { #include "libavcodec/avcodec.h" #include "libavformat/avformat.h" #include "libswscale/swscale.h" #include "libavutil/imgutils.h" }; #include "SDL_include/SDL.h" //Refresh Event #define SFM_REFRESH_EVENT (SDL_USEREVENT + 1) #define SFM_BREAK_EVENT (SDL_USEREVENT + 2) int thread_exit=0; int thread_pause=0; int sfp_refresh_thread(void *opaque){ thread_exit=0; thread_pause=0; while (!thread_exit) { if(!thread_pause){ SDL_Event event; event.type = SFM_REFRESH_EVENT; SDL_PushEvent(&event); } SDL_Delay(40); } thread_exit=0; thread_pause=0; //Break SDL_Event event; event.type = SFM_BREAK_EVENT; SDL_PushEvent(&event); return 0; } int main(int argc, char* argv[]) { AVFormatContext *pFormatCtx; int i, videoindex; AVCodecContext *pCodecCtx; AVCodec *pCodec; AVFrame *pFrame,*pFrameYUV; unsigned char *out_buffer; AVPacket *packet; int ret, got_picture; //------------SDL---------------- int screen_w,screen_h; SDL_Window *screen; SDL_Renderer* sdlRenderer; SDL_Texture* sdlTexture; SDL_Rect sdlRect; SDL_Thread *video_tid; SDL_Event event; struct SwsContext *img_convert_ctx; //char filepath[]="bigbuckbunny_480x272.h265"; char filepath[]="bigbuckbunny_480x272.h264"; av_register_all(); avformat_network_init(); pFormatCtx = avformat_alloc_context(); if(avformat_open_input(&pFormatCtx,filepath,NULL,NULL)!=0){ printf("Couldn't open input stream.\n"); return -1; } if(avformat_find_stream_info(pFormatCtx,NULL)<0){ printf("Couldn't find stream information.\n"); return -1; } videoindex=-1; for(i=0; i<pFormatCtx->nb_streams; i++) if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){ videoindex=i; break; } if(videoindex==-1){ printf("Didn't find a video stream.\n"); return -1; } pCodecCtx=pFormatCtx->streams[videoindex]->codec; pCodec=avcodec_find_decoder(pCodecCtx->codec_id); if(pCodec==NULL){ printf("Codec not found.\n"); return -1; } if(avcodec_open2(pCodecCtx, pCodec,NULL)<0){ printf("Could not open codec.\n"); return -1; } pFrame=av_frame_alloc(); pFrameYUV=av_frame_alloc(); out_buffer=(unsigned char *)av_malloc(av_image_get_buffer_size(AV_PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height,1)); av_image_fill_arrays(pFrameYUV->data, pFrameYUV->linesize,out_buffer, AV_PIX_FMT_YUV420P,pCodecCtx->width, pCodecCtx->height,1); //Output Info----------------------------- printf("---------------- File Information ---------------\n"); av_dump_format(pFormatCtx,0,filepath,0); printf("-------------------------------------------------\n");img_convert_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height, pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height, AV_PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL);if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)) { printf( "Could not initialize SDL - %s\n", SDL_GetError()); return -1; } //SDL 2.0 Support for multiple windows screen_w = pCodecCtx->width; screen_h = pCodecCtx->height; screen = SDL_CreateWindow("Simplest ffmpeg player's Window", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, screen_w, screen_h,SDL_WINDOW_OPENGL); if(!screen) { printf("SDL: could not create window - exiting:%s\n",SDL_GetError()); return -1; } sdlRenderer = SDL_CreateRenderer(screen, -1, 0); //IYUV: Y + U + V (3 planes) //YV12: Y + V + U (3 planes) sdlTexture = SDL_CreateTexture(sdlRenderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING,pCodecCtx->width,pCodecCtx->height); sdlRect.x=0; sdlRect.y=0; sdlRect.w=screen_w; sdlRect.h=screen_h; packet=(AVPacket *)av_malloc(sizeof(AVPacket)); video_tid = SDL_CreateThread(sfp_refresh_thread,NULL,NULL); //------------SDL End------------ //Event Loopfor (;;) { //Wait SDL_WaitEvent(&event); if(event.type==SFM_REFRESH_EVENT){ while(1){ if(av_read_frame(pFormatCtx, packet)<0) thread_exit=1; if(packet->stream_index==videoindex) break; } ret = avcodec_decode_video2(pCodecCtx, pFrame, &got_picture, packet); if(ret < 0){ printf("Decode Error.\n"); return -1; } if(got_picture){ sws_scale(img_convert_ctx, (const unsigned char* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameYUV->data, pFrameYUV->linesize); //SDL--------------------------- SDL_UpdateTexture( sdlTexture, NULL, pFrameYUV->data[0], pFrameYUV->linesize[0] ); SDL_RenderClear( sdlRenderer ); //SDL_RenderCopy( sdlRenderer, sdlTexture, &sdlRect, &sdlRect ); SDL_RenderCopy( sdlRenderer, sdlTexture, NULL, NULL); SDL_RenderPresent( sdlRenderer ); //SDL End----------------------- } av_free_packet(packet); }else if(event.type==SDL_KEYDOWN){ //Pause if(event.key.keysym.sym==SDLK_SPACE) thread_pause=!thread_pause; }else if(event.type==SDL_QUIT){ thread_exit=1; }else if(event.type==SFM_BREAK_EVENT){ break; } } sws_freeContext(img_convert_ctx); SDL_Quit(); //-------------- av_frame_free(&pFrameYUV); av_frame_free(&pFrame); avcodec_close(pCodecCtx); avformat_close_input(&pFormatCtx); return 0; }
