利用ffmpeg来进行视频解码的完整示例代码（H.264）

int Decode() { FILE * inpf; int nWrite; int i,p; int nalLen; unsigned char* Buf; int got_picture, consumed_bytes; unsigned char *DisplayBuf; DisplayBuf=(unsigned char *)malloc(60000); char outfile[] = "test.pgm"; //1.打开输入文件 inpf = fopen("test.264", "rb"); //outf = fopen("out.yuv", "wb"); if(!inpf) { goto Decodereturn; } nalLen = 0; Buf = (unsigned char*)calloc ( 1000000, sizeof(char)); //准备解码文件缓冲 //2.注册解码器，并且找到H264解码器 avcodec_init(); avcodec_register_all(); codec = avcodec_find_decoder(CODEC_ID_H264); if (!codec) { return 0; } //allocate codec context //分配解码器内存 c = avcodec_alloc_context(); if(!c){ return 0; } //open codec //3.打开解码器 if (avcodec_open(c, codec) < 0) { return 0; } //allocate frame buffer //分配解码器用的帧缓冲 picture = avcodec_alloc_frame(); if(!picture){ return 0; } rgbdatanew = (unsigned char *)malloc(sizeof(unsigned char)*(3 * width * height));while(!feof(inpf)) { //4.获取下一个NAL的长度,并且将NAL放入Buf nalLen = getNextNal(inpf, Buf); //5.对改NAL解码，解码的YUV数据存在picture中 consumed_bytes= avcodec_decode_video(c, picture, &got_picture, Buf, nalLen); if(consumed_bytes > 0) { //6.将picture中的YUV数据显示或者保存到文件 p=0; for(i=0; i<c->height; i++) { memcpy(DisplayBuf+p,picture->data[0] + i * picture->linesize[0], c->width); p+=c->width; } for(i=0; i<c->height/2; i++) { memcpy(DisplayBuf+p,picture->data[1] + i * picture->linesize[1], c->width/2);p+=c->width/2; } for(i=0; i<c->height/2; i++) { memcpy(DisplayBuf+p,picture->data[2] + i * picture->linesize[2], c->width/2);p+=c->width/2; } //显示画面 DisplayVideo(DisplayBuf); } } //7.关闭输入文件 if(inpf) fclose(inpf); Decodereturn: //8.关闭解码器,释放解码器内存 if(c) { avcodec_close(c); av_free(c); c = NULL; } //9.释放解码画面内存 if(picture) { av_free(picture); picture = NULL; } //10.释放解码文件缓冲 if(Buf) { free(Buf); Buf = NULL; } free(DisplayBuf); }