演示環境：CentOS 7

FFmpeg的H264編碼，需要x264庫支持

[root@localhost ~]# wget ftp://ftp.videolan.org/pub/x264/snapshots/last_x264.tar.bz2
[root@localhost ~]# tar xf last_x264.tar.bz2 
[root@localhost ~]# cd x264-snapshot-20171020-2245/
[root@localhost x264-snapshot-20171020-2245]# ./configure --prefix=/home/x264_dev --enable-shared --enable-static --disable-asm
[root@localhost x264-snapshot-20171020-2245]# make && make install 
[root@localhost x264-snapshot-20171020-2245]# echo ‘/home/x264_dev/lib/‘ >> /etc/ld.so.conf && ldconfig -v #添加x264庫到系統路路徑

編譯安裝FFmpeg：

[root@localhost ~]# wget http://ffmpeg.org/releases/ffmpeg-3.4.tar.bz2
[root@localhost ~]# tar xf ffmpeg-3.4.tar.bz2 
[root@localhost ~]# cd ffmpeg-3.4
[root@localhost ffmpeg-3.4]# export PKG_CONFIG_PATH=/home/x264_dev/lib/pkgconfig/:$PKG_CONFIG_PATH #根據PKG_CONFIG_PATH的值尋找x264庫路徑
[root@localhost ffmpeg-3.4]# ./configure --prefix=/home/ffmpeg_dev --enable-shared           --enable-static           --disable-optimizations   --disable-x86asm          --enable-libx264          --enable-gpl              --disable-cuvid           --disable-cuda            

[root@localhost ffmpeg-3.4]# make && make install
[root@localhost ffmpeg-3.4]# echo ‘/home/ffmpeg_dev/lib/‘ >> /etc/ld.so.conf && ldconfig -v #添加FFmpeg的庫到系統路路徑
#說明：若需使用x264需要 安裝x264庫：--enable-libx264 --enable-gpl 
#      關閉GPU視頻硬件加速的庫：    --disable-cuda   --disable-cuvid
#      生成靜態庫與動態庫           --enable-shared  --enable-static

下載測試視頻，截取一段轉為yuv格式（從第5秒，截取20秒）

[root@localhost ~]# cd /home/
[root@localhost home]# wget http://sh.yinyuetai.com/uploads/videos/common/0E3E014EBF3448D901AF3519C4A1D4E0.mp4
[root@localhost home]# /home/ffmpeg_dev/bin/ffmpeg -ss 5 -t 20 -i 0E3E014EBF3448D901AF3519C4A1D4E0.mp4  -s 1280x720 -pix_fmt yuv420p 1280x720_yuv420p.yuv
[root@localhost home]# /home/ffmpeg_dev/bin/ffmpeg -ss 5 -t 20 -i 0E3E014EBF3448D901AF3519C4A1D4E0.mp4  -s 1280x720 -pix_fmt yuv422p 1280x720_yuv422p.yuv

FFmpeg 常見的結構體

YUV420轉h264源程序：

[root@localhost ffmpeg_dev]# cat main.c 
#include <stdio.h>
#include <stdlib.h>

#include "libavutil/imgutils.h"
#include "libavutil/samplefmt.h"
#include "libavutil/opt.h"
#include "libavformat/avformat.h"

const char *inputFileName = NULL;
const char *outputFileName = NULL;
int frameWidth = 0;
int frameHeight = 0;
int bitRate = 0;
int frameTotal = 0;
FILE *pFileInput = NULL;
FILE *pFileOutput = NULL;

AVCodec *codec = NULL;
AVCodecContext *codecCtx = NULL;
AVFrame *frame = NULL;
AVPacket pkt;

static int parse_input_paramaters(int argc, char **argv)
{
    inputFileName = argv[1];
    outputFileName = argv[2];

    pFileInput = fopen(inputFileName, "rb");
    if(NULL == pFileInput)
    {
        printf("open file ERR: [%s] \n", inputFileName);
        return -1;
    }

    pFileOutput = fopen(outputFileName, "wb+");
    if(NULL == pFileInput)
    {
        printf("open file ERR: [%s] \n", outputFileName);
        return -1;
    }

    frameWidth = atoi(argv[3]);
    frameHeight = atoi(argv[4]);
    bitRate = atoi(argv[5]);
    frameTotal = atoi(argv[6]);
    return 0;
}

static int read_yuv_data(int color)
{
    //color = 0 -> Y
    //color = 1 -> U
    //color = 2 -> V
    int color_height = color == 0 ? frameHeight : frameHeight / 2;
    int color_width  = color == 0 ? frameWidth  : frameWidth  / 2;
    int color_size = color_height * color_width;
    int color_stride = frame->linesize[color];

    if(color_width == color_stride)
    {
        //printf("color_width == color_stride,color=[%d],color_stride=[%d] \n", color, color_stride);
        fread(frame->data[color], color_size, 1, pFileInput);
    }
    //else
    //{
    //    printf("color_width != color_stride,color=[%d] \n", color);
    //    int i;
    //    for(i = 0; i < color_height; i++)
    //    {
    //        fread(frame->data[color] + i * color_stride, color_width, 1, pFileInput);
    //    }
    //}
    return color_size;
}


int main(int argc, char **argv)
{
    if(parse_input_paramaters(argc, argv) == 0)
    {
        printf("inputFile:%s \n", inputFileName);
        printf("outputFile:%s \n", outputFileName);
        printf("Frame resolution::[%d*%d] \n", frameWidth, frameHeight);
        printf("freamToEncode=%d\n", frameTotal);
        printf("rate:%d \n", bitRate);
    }
    else
    {
        printf("init ERROR\n");
        return -1;
    }


    avcodec_register_all();//註冊編解碼組件
    codec = avcodec_find_encoder(AV_CODEC_ID_H264);//查找編解碼器
    if(NULL == codec)
    {
        printf("find AV_CODEC_ID_H264 fail! \n");
        return -1;
    }

    //分配AVCodecContex實例
    codecCtx = avcodec_alloc_context3(codec);
    if(NULL == codecCtx)
    {
        printf("avcodec_alloc_context3  ERROR\n");
        return -1;
    }

    //設置編解碼器的參數
    codecCtx->width = frameWidth;//幀高
    codecCtx->height = frameHeight;
    codecCtx->bit_rate = bitRate;//比特率
    AVRational r = {1, 25};//設置幀率
    codecCtx->time_base = r;//設置幀率
    codecCtx->gop_size =12;
    codecCtx->max_b_frames = 1;
    codecCtx->pix_fmt = AV_PIX_FMT_YUV420P;
    av_opt_set(codecCtx->priv_data, "preset", "slow", 0);

    //打開編碼器
    if(avcodec_open2(codecCtx, codec, NULL) < 0)
    {
        printf("avcodec_open2 ERR\n");
    }

    frame = av_frame_alloc();
    if(NULL == frame)
    {
        printf("av_frame_alloc err \n");
        return -1;
    }

    //分配AVframe及像素存儲空間
    frame->width = codecCtx->width;
    frame->height = codecCtx->height;
    frame->format = codecCtx->pix_fmt;
    if(av_image_alloc(frame->data, frame->linesize, frame->width, frame->height, frame->format, 32) < 0)//32 表示對齊
    {
        printf("ERROR av_image_alloc\n");
    }

    int i;
    for(i = 0; i < frameTotal; i++)
    {
        av_init_packet(&pkt);
        pkt.data = NULL;
        pkt.size = 0;

        read_yuv_data(0);
        read_yuv_data(1);
        read_yuv_data(2);
        frame->pts = i;

        int got_packet;
        //int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr);
        if(avcodec_encode_video2(codecCtx, &pkt, (const AVFrame *)frame, &got_packet) < 0)
        {
            printf("avcodec_encodec_video2 ERR \n");
            return -1;
        }
        if(got_packet)
        {
            printf("Write packet of frame [%d], size=[%d] \n", i, pkt.size);
            //size_t fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream);
            fwrite(pkt.data, 1, pkt.size, pFileOutput);
            av_packet_unref(&pkt);
        }


    }

    int got_packet = 1;
    while(got_packet)
    {
        if(avcodec_encode_video2(codecCtx, &pkt, NULL, &got_packet) < 0)
        {
            printf("avcodec_encodec_video2 ERR \n");
            return -1;
        }
        if(got_packet)
        {
            printf("Write cache packet of frame [%d], size=[%d] \n", i, pkt.size);
            fwrite(pkt.data, 1, pkt.size, pFileOutput);
            av_packet_unref(&pkt);
        }
    }


    fclose(pFileInput);
    fclose(pFileOutput);
    avcodec_close(codecCtx);
    av_free(codecCtx);
    av_freep(&frame->data[0]);
    av_frame_free(&frame);

    return 0;
}

[root@localhost ffmpeg_dev]#

makefile文件

[root@localhost ffmpeg_dev]# cat makefile 
FLAGS = -Wall -g
INCLUDEPATH = -I /home/ffmpeg_dev/include/
LIBPATH = -L  /home/ffmpeg_dev/lib/
LIBS= -l avcodec          -l pthread          -l avutil           -l m                -l dl               -l swresample 
exe=yuv2h264

$(exe):
	gcc main.c  ${FLAGS}  ${INCLUDEPATH} ${LIBPATH} ${LIBS} -o $@

clean:
	rm -rf ${exe}

[root@localhost ffmpeg_dev]#

編譯並運行，將YUV420文件轉為H264

[root@localhost ffmpeg_dev]# cat auto.sh 
make clean
make
#提示  : Potplayer可以直接播放H264文件
#程序名:  YUV420P文件名， H264輸出文件名， YUV的寬與高， 壓縮比特率， 需要編碼多少幀(不要大於YUV文件的幀數)
./yuv2h264 1280x720_420P.yuv  1280x720.h264 1280 720 819200 250

[root@localhost ffmpeg_dev]#

播放器打開H264文件：

本文出自 “李春利” 博客，請務必保留此出處http://990487026.blog.51cto.com/10133282/1974942

02 使用FFmpeg庫， YUV420轉H264編碼