ffmpeg-截取视频段

目的

截取视频中的一段

思路

先是将源媒体文件copy一份 知道截取视频的起始点与结束点

主要API

1. av_seek_frame():跳一段时间

源码

#include
#include
#include

static void log_packet(const AVFormatContext *fmt_ctx,const AVPacket *pkt,const char *tag){
   
	AVRational *time_base = &fmt_ctx->streams[pkt->stream_index]->time_base;

	printf("%s: pts : %s pts_time:%s dts:%s dts_time:%s duration :%s duration_time:%s stream_index:%d\n",
	     tag,
	     av_ts2str(pkt->pts),av_ts2timestr(pkt->pts,time_base),
	     av_ts2str(pkt->dts),av_ts2timestr(pkt->pts,time_base),
	     av_ts2str(pkt->duration),av_ts2timestr(pkt->duration,time_base),
	     pkt->stream_index);


}

int cut_video(double from_seconds,double end_seconds,const char* in_filename, const char* out_filename){
   
	AVOutputFormat *ofmt =NULL;
	AVFormatContext *ifmt_ctx= NULL, *ofmt_ctx = NULL;
	AVPacket pkt;
	int ret,i;

	/*input*/

	//1.open in_filename
	if((ret = avformat_open_input(&ifmt_ctx,in_filename,0,0))<0){
   
		fprintf(stderr,"Could not open input file '%s'",in_filename);
		goto end;
	}

	if((ret = avformat_find_stream_info(ifmt_ctx,0))<0){
   
		fprintf(