使用FFMpeg进行H264编码

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使用FFMpeg可以很方便的对音视频进行编码，并且写文件。

下面的代码是将5幅1280*720大小的图片进行编码，并且写到文件中。

代码有些乱，但希望能抛砖引玉，对学习这方面的朋友有帮助。

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CFile file[5];

BYTE *szTxt[5];

int nWidth = 0;

int nHeight= 0;

int nDataLen=0;

int nLen;

CString csFileName;

for (int fileI = 1; fileI <= 5; fileI ++)

{

csFileName.Format("e:\\pics\\%d.bmp", fileI);

file[fileI - 1].Open(csFileName,CFile::modeRead | CFile::typeBinary);

nLen = file[fileI - 1].GetLength();

szTxt[fileI -1] = new BYTE[nLen];

file[fileI - 1].Read(szTxt[fileI - 1], nLen);

file[fileI - 1].Close();

//BMP bmi;//BITMAPINFO bmi;

//int nHeadLen = sizeof(BMP);

BITMAPFILEHEADER bmpFHeader;

BITMAPINFOHEADER bmpIHeader;

memcpy(&bmpFHeader,szTxt[fileI -1],sizeof(BITMAPFILEHEADER));

int nHeadLen = bmpFHeader.bfOffBits - sizeof(BITMAPFILEHEADER);

memcpy(&bmpIHeader,szTxt[fileI - 1]+sizeof(BITMAPFILEHEADER),nHeadLen);

nWidth = bmpIHeader.biWidth;// 464;// bmi.bmpInfo.bmiHeader.biWidth;// ;

nHeight = bmpIHeader.biHeight;//362;// bmi.bmpInfo.bmiHeader.biHeight;// ;

szTxt[fileI - 1] += bmpFHeader.bfOffBits;

nDataLen = nLen-bmpFHeader.bfOffBits;

}

av_register_all();

avcodec_register_all();

AVFrame *m_pRGBFrame = new AVFrame[1]; //RGB帧数据

AVFrame *m_pYUVFrame = new AVFrame[1];; //YUV帧数据

AVCodecContext *c= NULL;

AVCodecContext *in_c= NULL;

AVCodec *pCodecH264; //编码器

uint8_t * yuv_buff;//

//查找h264编码器

pCodecH264 = avcodec_find_encoder(CODEC_ID_H264);

if(!pCodecH264)

{

fprintf(stderr, "h264 codec not found\n");

exit(1);

}

c= avcodec_alloc_context3(pCodecH264);

c->bit_rate = 3000000;// put sample parameters

c->width =nWidth;//

c->height = nHeight;//

// frames per second

AVRational rate;

rate.num = 1;

rate.den = 25;

c->time_base= rate;//(AVRational){1,25};

c->gop_size = 10; // emit one intra frame every ten frames

c->max_b_frames=1;

c->thread_count = 1;

c->pix_fmt = PIX_FMT_YUV420P;//PIX_FMT_RGB24;

//av_opt_set(c->priv_data, /*"preset"*/"libvpx-1080p.ffpreset", /*"slow"*/NULL, 0);

//打开编码器

if(avcodec_open2(c,pCodecH264,NULL)<0)

TRACE("不能打开编码库");

int size = c->width * c->height;

yuv_buff = (uint8_t *) malloc((size * 3) / 2); // size for YUV 420

//将rgb图像数据填充rgb帧

uint8_t * rgb_buff = new uint8_t[nDataLen];

//图象编码

int outbuf_size=100000;

uint8_t * outbuf= (uint8_t*)malloc(outbuf_size);

int u_size = 0;

FILE *f=NULL;

char * filename = "e:\\pics\\myData.h264";

f = fopen(filename, "wb");

if (!f)

{

TRACE( "could not open %s\n", filename);

exit(1);

}

//初始化SwsContext

SwsContext * scxt = sws_getContext(c->width,c->height,PIX_FMT_BGR24,c->width,c->height,PIX_FMT_YUV420P,SWS_POINT,NULL,NULL,NULL);

AVPacket avpkt;

//AVFrame *pTFrame=new AVFrame

for (int i=0;i<250;++i)

{

//AVFrame *m_pYUVFrame = new AVFrame[1];

int index = (i / 25) % 5;

memcpy(rgb_buff,szTxt[index],nDataLen);

avpicture_fill((AVPicture*)m_pRGBFrame, (uint8_t*)rgb_buff, PIX_FMT_RGB24, nWidth, nHeight);

//将YUV buffer 填充YUV Frame

avpicture_fill((AVPicture*)m_pYUVFrame, (uint8_t*)yuv_buff, PIX_FMT_YUV420P, nWidth, nHeight);

// 翻转RGB图像

m_pRGBFrame->data[0] += m_pRGBFrame->linesize[0] * (nHeight - 1);

m_pRGBFrame->linesize[0] *= -1;

m_pRGBFrame->data[1] += m_pRGBFrame->linesize[1] * (nHeight / 2 - 1);

m_pRGBFrame->linesize[1] *= -1;

m_pRGBFrame->data[2] += m_pRGBFrame->linesize[2] * (nHeight / 2 - 1);

m_pRGBFrame->linesize[2] *= -1;

//将RGB转化为YUV

sws_scale(scxt,m_pRGBFrame->data,m_pRGBFrame->linesize,0,c->height,m_pYUVFrame->data,m_pYUVFrame->linesize);

int got_packet_ptr = 0;

av_init_packet(&avpkt);

avpkt.data = outbuf;

avpkt.size = outbuf_size;

u_size = avcodec_encode_video2(c, &avpkt, m_pYUVFrame, &got_packet_ptr);

if (u_size == 0)

{

fwrite(avpkt.data, 1, avpkt.size, f);

}

}

fclose(f);

delete []m_pRGBFrame;

delete []m_pYUVFrame;

delete []rgb_buff;

free(outbuf);

avcodec_close(c);

av_free(c);