接着上一篇
http://blog.csdn.net/openswc/article/details/51597755
二、ffmpeg 将YUV编码为.h264
1.下载安装ffmpeg
./configure --enable-libx264 --enable-gpl --enable-shared
make
make install
2.用安装好的ffmpeg用命令将YUV编码为.h264
ffmpeg -s 480x272 -i ds_480x272.yuv -r 25 -vcodec libx264 ds2.h264
yuv文件：
https://github.com/leixiaohua1020/simplest_ffmpeg_video_encoder/blob/master/ds_480x272.yuv
3.用C语言代码调用ffmpeg接口将YUV编码为.h264
编译命令：编译之前，执行下ldconfig命令，把libx264库更新到系统库路径；
gcc simplest_ffmpeg_video_encoder_pure.cpp -g -o sffmpegencoder -I /usr/local/include -L /usr/local/lib -lavformat -lavcodec -lavutil
代码如下
simplest_ffmpeg_video_encoder_pure.cpp
/*
* Simplest FFmpeg Video Encoder Pure
*
* Lei Xiaohua
* leixiaohua1020@126.com
* Communication University of China / Digital TV Technology
* http://blog.csdn.net/leixiaohua1020
*
* This software encode YUV420P data to video bitstream
* (Such as H.264, H.265, VP8, MPEG2 etc).
* It only uses libavcodec to encode video (without libavformat)
* It's the simplest video encoding software based on FFmpeg.
* Suitable for beginner of FFmpeg
*
*
* modify: openswc
* build:
* gcc simplest_ffmpeg_video_encoder_pure.cpp -g -o sffmpegencoder -I /usr/local/include -L /usr/local/lib -lavformat -lavcodec -lavutil
* before use sffmpegencoder: you need to excute the following command: su root; ldconfig;
* or there is an error:
* ./sffmpegencoder: error while loading shared libraries: libavcodec.so.57: cannot open shared object file: No such file or directory
*/
#include <stdio.h>
#define __STDC_CONSTANT_MACROS
#ifdef _WIN32
//Windows
extern "C"
{
#include "libavutil/opt.h"
#include "libavcodec/avcodec.h"
#include "libavutil/imgutils.h"
};
#else
//Linux...
#ifdef __cplusplus
extern "C"
{
#endif
#include <libavutil/opt.h>
#include <libavcodec/avcodec.h>
#include <libavutil/imgutils.h>
#ifdef __cplusplus
};
#endif
#endif
//test different codec
#define TEST_H264 1
#define TEST_HEVC 0
int main(int argc, char* argv[])
{
AVCodec *pCodec;
AVCodecContext *pCodecCtx= NULL;
int i, ret, got_output;
FILE *fp_in;
FILE *fp_out;
AVFrame *pFrame;
AVPacket pkt;
int y_size;
int framecnt=0;
char filename_in[]="../ds_480x272.yuv";
#if TEST_HEVC
AVCodecID codec_id=AV_CODEC_ID_HEVC;
char filename_out[]="ds.hevc";
#else
AVCodecID codec_id=AV_CODEC_ID_H264;
char filename_out[]="ds.h264";
#endif
int in_w=480,in_h=272;
int framenum=100;
avcodec_register_all();
pCodec = avcodec_find_encoder(codec_id);
if (!pCodec) {
printf("Codec not found\n");
return -1;
}
pCodecCtx = avcodec_alloc_context3(pCodec);
if (!pCodecCtx) {
printf("Could not allocate video codec context\n");
return -1;
}
pCodecCtx->bit_rate = 400000;
pCodecCtx->width = in_w;
pCodecCtx->height = in_h;
pCodecCtx->time_base.num=1;
pCodecCtx->time_base.den=25;
pCodecCtx->gop_size = 10;
pCodecCtx->max_b_frames = 1;
pCodecCtx->pix_fmt = AV_PIX_FMT_YUV420P;
if (codec_id == AV_CODEC_ID_H264)
av_opt_set(pCodecCtx->priv_data, "preset", "slow", 0);
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0) {
printf("Could not open codec\n");
return -1;
}
pFrame = av_frame_alloc();
if (!pFrame) {
printf("Could not allocate video frame\n");
return -1;
}
pFrame->format = pCodecCtx->pix_fmt;
pFrame->width = pCodecCtx->width;
pFrame->height = pCodecCtx->height;
ret = av_image_alloc(pFrame->data, pFrame->linesize, pCodecCtx->width, pCodecCtx->height,
pCodecCtx->pix_fmt, 16);
if (ret < 0) {
printf("Could not allocate raw picture buffer\n");
return -1;
}
//Input raw data
fp_in = fopen(filename_in, "rb");
if (!fp_in) {
printf("Could not open %s\n", filename_in);
return -1;
}
//Output bitstream
fp_out = fopen(filename_out, "wb");
if (!fp_out) {
printf("Could not open %s\n", filename_out);
return -1;
}
y_size = pCodecCtx->width * pCodecCtx->height;
//Encode
for (i = 0; i < framenum; i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
//Read raw YUV data
if (fread(pFrame->data[0],1,y_size,fp_in)<= 0|| // Y
fread(pFrame->data[1],1,y_size/4,fp_in)<= 0|| // U
fread(pFrame->data[2],1,y_size/4,fp_in)<= 0){ // V
return -1;
}else if(feof(fp_in)){
break;
}
pFrame->pts = i;
/* encode the image */
ret = avcodec_encode_video2(pCodecCtx, &pkt, pFrame, &got_output);
if (ret < 0) {
printf("Error encoding frame\n");
return -1;
}
if (got_output) {
printf("Succeed to encode frame: %5d\tsize:%5d\n",framecnt,pkt.size);
framecnt++;
fwrite(pkt.data, 1, pkt.size, fp_out);
av_free_packet(&pkt);
}
}
//Flush Encoder
for (got_output = 1; got_output; i++) {
ret = avcodec_encode_video2(pCodecCtx, &pkt, NULL, &got_output);
if (ret < 0) {
printf("Error encoding frame\n");
return -1;
}
if (got_output) {
printf("Flush Encoder: Succeed to encode 1 frame!\tsize:%5d\n",pkt.size);
fwrite(pkt.data, 1, pkt.size, fp_out);
av_free_packet(&pkt);
}
}
fclose(fp_out);
avcodec_close(pCodecCtx);
av_free(pCodecCtx);
av_freep(&pFrame->data[0]);
av_frame_free(&pFrame);
return 0;
}
三、如果播放.h264文件
用VLC media player即可播放yuv转换后的.h264视频文件；
VLC media player网站
http://www.videolan.org