FFmpge 剥离视屏文件的YUV

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#include <stdio.h>

#include "pch.h"

#define _CRT_SECURE_NO_WARNINGS

#define __STDC_CONSTANT_MACROS

extern "C"

{

#include "libavcodec/avcodec.h"

#include "libavformat/avformat.h"

#include "libswscale/swscale.h"

#include "libswscale/swscale.h"

};

int main(int argc, char* argv[])

{

AVFormatContext* pAVFormatContext;

AVCodecContext* pAVCodecContext;

AVCodec* pAVCodec;

AVPacket* pAVPacket;

AVFrame* pAvFrame;

AVFrame* pFrameYUV;

int videoindex = -1;

uint8_t *out_buffer;

int frame_cnt = 0;

int got_pic, ret;

struct SwsContext *img_convert_ctx;

char filepath[] = "cuc_ieschool.flv";

FILE* file_yuv = fopen("shao_test.yuv", "wb+");

av_register_all();

avformat_network_init();

pAVFormatContext = avformat_alloc_context();

if (avformat_open_input(&pAVFormatContext, filepath, NULL, NULL) != 0) {

printf("Couldn't open input stream.\n");

return -1;

}

if (avformat_find_stream_info(pAVFormatContext, NULL) < 0) {

printf("Couldn't find stream information.\n");

return -1;

}

printf("video duration: %d", pAVFormatContext->duration);

printf("video formatName: %s", pAVFormatContext->iformat->name);

for (int i = 0; i < pAVFormatContext->nb_streams;i ++) {

if (pAVFormatContext->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

videoindex = i;

break;

}

}

if (videoindex == -1) {

printf("Didn't find a video stream.\n");

return -1;

}

pAVCodecContext = pAVFormatContext->streams[videoindex]->codec;

pAVCodec = avcodec_find_decoder(pAVCodecContext->codec_id);

printf("video width=%d , height = %d\n", pAVCodecContext->width,pAVCodecContext->height);

if (pAVCodec == NULL) {

printf("cannot find codec");

return -1;

}

if (avcodec_open2(pAVCodecContext,pAVCodec,NULL) < 0) {

printf("can not open file \n");

return -1;

}

av_dump_format(pAVFormatContext, 0, filepath, 0);

pAvFrame = av_frame_alloc();

pFrameYUV = av_frame_alloc();

pAVPacket = reinterpret_cast<AVPacket*> (av_malloc(sizeof(AVPacket)));

out_buffer = (uint8_t*)av_malloc(avpicture_get_size(PIX_FMT_YUV420P, pAVCodecContext->width, pAVCodecContext->height));

avpicture_fill((AVPicture *)pFrameYUV, out_buffer, PIX_FMT_YUV420P, pAVCodecContext->width, pAVCodecContext->height);

img_convert_ctx = sws_getContext(pAVCodecContext->width, pAVCodecContext->height, pAVCodecContext->pix_fmt,

pAVCodecContext->width, pAVCodecContext->height, PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL);

int yuv_size = pAVCodecContext->width * pAVCodecContext->height;

while (av_read_frame(pAVFormatContext, pAVPacket) >= 0) {

if (pAVPacket->stream_index == videoindex) {

/*

* 在此处添加输出H264码流的代码

* 取自于packet，使用fwrite()

*/

ret = avcodec_decode_video2(pAVCodecContext, pAvFrame, &got_pic, pAVPacket);

if (ret < 0) {

printf("Decode Error.\n");

return -1;

}

if (got_pic) {

sws_scale(img_convert_ctx, (const uint8_t* const*)pAvFrame->data, pAvFrame->linesize, 0, pAVCodecContext->height,

pFrameYUV->data, pFrameYUV->linesize);

printf("Decoded frame index: %d\n", frame_cnt);

fwrite(pFrameYUV->data[0], 1, yuv_size, file_yuv);

fwrite(pFrameYUV->data[1], 1, yuv_size / 4, file_yuv);

fwrite(pFrameYUV->data[2], 1, yuv_size / 4, file_yuv);

/*

* 在此处添加输出YUV的代码

* 取自于pFrameYUV，使用fwrite()

*/

frame_cnt++;

}

}

av_free_packet(pAVPacket);

}

//FIX: Flush Frames remained in Codec

while (1) {

ret = avcodec_decode_video2(pAVCodecContext, pAvFrame, &got_pic, pAVPacket);

if (ret < 0)

break;

if (got_pic) {

fwrite(pAvFrame->data[0], 1, yuv_size, file_yuv);

fwrite(pAvFrame->data[1], 1, yuv_size / 4, file_yuv);

fwrite(pAvFrame->data[2], 1, yuv_size / 4, file_yuv);

printf("decode frame cuss %d\n", pAVPacket->dts);

}

av_free_packet(pAVPacket);

}

av_frame_free(&pAvFrame);

avcodec_close(pAVCodecContext);

avformat_close_input(&pAVFormatContext);

return 0;

}

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