ffmpeg API录制rtsp视频流

妖狐艹你老母 2022-08-26 00:55 176阅读 0赞

这里在录制时，并没有进行转码，只是相当于把rtsp视频直接保存到一个文件中。

#include <stdio.h>
    
    #ifdef __cplusplus
    extern "C" {
    #endif
    #include <libavcodec/avcodec.h>
    #include <libavformat/avformat.h>
    //#include <libswscale/swscale.h>
    
    #ifdef _MSC_VER
    int strcasecmp(const char *s1, const char *s2)
    {
    	while ((*s1 != '\0')
    		&& (tolower(*(unsigned char *) s1) ==
    		tolower(*(unsigned char *) s2))) 
    	{
    		s1++;
    		s2++;
    	}
    
    	return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);
    }
    int strncasecmp(const char *s1, const char *s2, unsigned int n)
    {
    	if (n == 0)
    		return 0;
    
    	while ((n-- != 0)
    		&& (tolower(*(unsigned char *) s1) ==
    		tolower(*(unsigned char *) s2))) {
    			if (n == 0 || *s1 == '\0' || *s2 == '\0')
    				return 0;
    			s1++;
    			s2++;
    	}
    
    	return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);
    }
    #endif //_MSC_VER
    
    #ifdef __cplusplus
    }
    #endif
    
    /***********************************************************
    '** stream_component_open
    *	Description: 
    *			 //open the stream component for video/audio
    *
    *
    *	Params:ic-pointer which contains the url and codec details 
    :stream_index-index denoting video or audio stream
    ***********************************************************/
    int stream_component_open(AVFormatContext *ic, int stream_index)
    {
    	AVCodecContext *enc;
    	AVCodec *codec;
    
    	if (stream_index < 0 || stream_index >= (int)ic->nb_streams)
    		return -1;
    	enc = ic->streams[stream_index]->codec;
    
    	/* prepare audio output */
    	if (enc->codec_type == CODEC_TYPE_AUDIO)
    	{
    		if (enc->channels > 0)
    			enc->request_channels = FFMIN(2, enc->channels);
    		else
    			enc->request_channels = 2;
    
    		/*Hardcoding the codec id to PCM_MULAW if the audio
    		codec id returned by the lib is CODEC_ID_NONE */
    
    		if(enc->codec_id == CODEC_ID_NONE)
    		{
    			enc->codec_id = CODEC_ID_PCM_MULAW;
    			enc->channels = 1;
    			enc->sample_rate = 16000;
    			enc->bit_rate = 128;
    		}
    	}
    
    	codec = avcodec_find_decoder(enc->codec_id);
    	enc->idct_algo			= FF_IDCT_AUTO;
    	enc->flags2   |= CODEC_FLAG2_FAST;
    	enc->skip_frame			= AVDISCARD_DEFAULT;
    	enc->skip_idct			= AVDISCARD_DEFAULT;
    	enc->skip_loop_filter	= AVDISCARD_DEFAULT;
    	enc->error_concealment	= 3;
    
    	if (!codec || avcodec_open(enc, codec) < 0)
    		return -1;
    	avcodec_thread_init(enc, 1);
    	enc->thread_count= 1;
    	ic->streams[stream_index]->discard = AVDISCARD_DEFAULT;
    
    	return 0;
    }
    //声明函数
    int enable_local_record(AVFormatContext *ic/*已经打开的视频文件上下文*/,
    						int videostream,int audiostream,
    						AVFormatContext **out_oc,const char * ofile,const char * ofileformat);
    
    int exit_onerr(const char * err_desc/*错误描述*/,int err_code/*错误码*/)
    {
    	printf("%s\n",err_desc);
    	system("pause");//暂停，查看错误描述
    	return err_code;
    }
    int main(int argc, char* argv[])
    {
    	//初始化ffmpeg链表结构
    	avcodec_register_all();						// Register all formats and codecs
    	av_register_all();
    
    	AVPacket  packet;
    
    	//打开文件
    	AVFormatContext * ic = NULL;
    	const char * rtsp_url = "rtsp://192.168.0.168:8557/PSIA/Streaming/channels/2?videoCodecType=H.264";
    	if(av_open_input_file(&ic, rtsp_url, NULL, 0, NULL)!=0)
    	{						
    		return exit_onerr("can't open file.",-1);
    	}
    	if(!ic)
    	{
    		return exit_onerr("unknow error.",-2);
    	}
    	ic ->max_analyze_duration = 1000;
    
    	//get streams information
    	if(av_find_stream_info(ic)<0)
    	{
    		av_close_input_file(ic);//退出前，记得释放资源
    		ic = NULL;
    		return exit_onerr("con't init streams information.",-3);
    	}
    
    
    	//find stream
    	int videoStream=-1;	// Didn't find a video stream
    	int audioStream=-1;	// Didn't find a audio stream 
    	// Find the first video stream
    	for(int i=0; i<ic ->nb_streams; i++)
    	{
    		if( ic ->streams[i]->codec->codec_type==CODEC_TYPE_VIDEO)
    		{ 
    			videoStream=i;
    			break;
    		}
    	}
    	// Find the first audio stream
    	for(int i=0; i<ic ->nb_streams; i++)
    	{
    		if( ic ->streams[i]->codec->codec_type==CODEC_TYPE_AUDIO)
    		{
    			audioStream=i;
    			break;
    		}
    	}
    	//判断视频文件中是否包含音视频流，如果没有，退出
    	if(audioStream<0 && videoStream<0)
    	{
    		av_close_input_file(ic);//退出前，记得释放资源
    		ic = NULL;
    		return exit_onerr("con't find a audio stream or video stream",-4);
    	}
    
    	//open the stream component for video
    	int videoComponent = -1;
    	if(videoStream >= 0)
    	{
    		videoComponent = stream_component_open(ic, videoStream); 
    		if(videoComponent<0)
    		{
    			av_close_input_file(ic);//退出前，记得释放资源
    			return exit_onerr("not supported video stream",-5);//要求重新编译ffmpeg以支持该种编码格式
    		}
    	}
    	//open the stream component for audio
    	int audioComponent = -1;
    	if(audioStream >= 0)
    	{
    		audioComponent = stream_component_open(ic, audioStream); 
    		if(audioComponent<0)
    		{
    			av_close_input_file(ic);//退出前，记得释放资源
    			return exit_onerr("not supported audio stream",-6);//要求重新编译ffmpeg以支持该种编码格式
    		}
    	}
    
    
    	//
    	int ret = 0;
    	//初始化并打开录像
    	AVFormatContext * oc = NULL;
    	const char * out_file_name = "D:\\test.avi";
    
    	//获取一帧完整的图像用于初始化ffmpeg内部的一些结构体数据(这里使用什么数据尚未清楚，请自行查看)，否则会出现写文件头失败
    	int got_picture = 0;
    	AVFrame *frame = avcodec_alloc_frame();
    	while( 1 )
    	{
    		if(av_read_frame( ic, &packet)<0)
    		{
    			av_free_packet(&packet);
    			av_close_input_file(ic);//退出前，记得释放资源
    			return exit_onerr("read frame error.",-7);//读取视频帧失败
    		}
    		if(packet.stream_index == videoStream)
    		{
    			avcodec_decode_video(ic->streams[videoStream]->codec, frame, &got_picture, packet.data, packet.size);
    		}
    		av_free_packet(&packet);
    		if(got_picture)
    			break;
    	}
    	av_free(frame);
    
    	ret = enable_local_record(ic,videoStream,audioStream,&oc,out_file_name,"avi");
    
    	if(ret <0 || !oc)
    	{
    		//退出前，记得释放资源，现在又多了个oc参数需要释放
    		if(oc)
    		{
    			///cleanup the output contents format
    			for(unsigned int i=0;i< oc->nb_streams;i++)
    			{
    				av_metadata_free(&oc ->streams[i]->metadata);
    				av_free(oc ->streams[i]->codec);
    				av_free(oc ->streams[i]);
    			}
    			for(unsigned int i=0;i<oc ->nb_programs;i++) 
    			{
    				av_metadata_free(&oc ->programs[i]->metadata);
    			}
    			for(unsigned int i=0;i<oc ->nb_chapters;i++) 
    			{
    				av_metadata_free(&oc ->chapters[i]->metadata);
    			}
    			av_metadata_free(&oc ->metadata);
    			av_free(oc);
    		}
    		av_close_input_file(ic);
    		return exit_onerr("can't init out file.",-8);
    	}
    
    	//开始录像
    	int video_dts = 0,audio_dts = 0;//时间戳
    	int total_frame = 300;//写300帧文件
    	while(total_frame--)
    	{
    		if( av_read_frame( ic, &packet) <0 )		//read the packet
    		{		
    			//读取数据出错
    			av_free_packet(&packet);
    			break;
    		}
    		if(packet.data && (packet.stream_index == videoStream || packet.stream_index == audioStream) )
    		{
    			//计算时间视频戳，顺序+1，这里可以多研究几种编码的音视频文件，求其时间戳生成格式，h264编码顺序加1即可
    			if(packet.stream_index == videoStream)
    			{
    				packet.dts = video_dts++;
    				packet.pts = video_dts;
    			}
    			else if(packet.stream_index == audioStream)//计算音频时间戳
    			{
    				packet.dts = audio_dts++;
    				packet.pts = audio_dts * (1000 * packet.size /ic ->streams[packet.stream_index]->codec ->sample_rate);
    			}
    			packet.flags |= PKT_FLAG_KEY;
    			if(av_interleaved_write_frame(oc,&packet)<0)
    			{
    				printf("st:%d\twrite frame failed.\n",packet.stream_index);
    			}
    		}
    		av_free_packet(&packet);
    	}
    
    	//关闭录像文件和输入文件
    
    	//写文件尾
    	av_write_trailer(oc);
    
    	/* close the output file if need.*/
    	if (!(oc ->oformat->flags & AVFMT_NOFILE)) 
    	{
    		url_fclose(oc->pb);
    	}
    
    	//释放资源
    	/*cleanup the output contents format*/
    	for(unsigned int i=0;i< oc->nb_streams;i++)
    	{
    		av_metadata_free(&oc ->streams[i]->metadata);
    		av_free(oc ->streams[i]->codec);
    		av_free(oc ->streams[i]);
    	}
    	for(unsigned int i=0;i<oc ->nb_programs;i++) 
    	{
    		av_metadata_free(&oc ->programs[i]->metadata);
    	}
    	for(unsigned int i=0;i<oc ->nb_chapters;i++) 
    	{
    		av_metadata_free(&oc ->chapters[i]->metadata);
    	}
    	av_metadata_free(&oc ->metadata);
    	av_free(oc);
    
    	av_close_input_file(ic);
    
    	return 0;
    }
    
    //初始化录像文件，代码较长，可写成函数
    /*
    *return <0  failed, 0 success
    */
    int enable_local_record(AVFormatContext *ic/*已经打开的视频文件上下文*/,int videostream,int audiostream,AVFormatContext **out_oc,const char * ofile,const char * ofileformat)
    {
    	AVFormatContext *oc		= NULL;//
    	AVOutputFormat  *fmt	= NULL;
    
    	if( ofileformat )
    	{
    		fmt = av_guess_format(ofileformat, NULL, NULL);
    	}
    	if(!fmt)
    	{
    		printf("out file format \"%s\" invalidate.\n",ofileformat);
    		return -1;
    	}
    
    	/*******************************************init output contents begin**********************************************************/
    	/* allocate the output media context */
    	oc = avformat_alloc_context();
    	if (!oc) 
    	{
    		printf("out of memory.\n");
    		return -2;//内存分配失败
    	}
    
    	*out_oc = oc;
    
    	oc ->oformat = fmt;
    	sprintf_s( oc ->filename, sizeof( oc ->filename), "%s", ofile);
    	av_metadata_conv(oc, fmt->metadata_conv, NULL);
    	if( videostream >=0 )
    	{
    		//AVCodecContext* pCodecCtx= ->streams[videostream]->codec;;
    		//add video stream
    		AVStream * st = av_new_stream(oc, videostream);
    		if(!st)
    		{
    			printf("can not add a video stream.\n");
    			return -3;
    		}
    		st->codec->codec_id			=  ic ->streams[videostream] ->codec->codec_id;
    		st->codec->codec_type		=  CODEC_TYPE_VIDEO;
    		st->codec->bit_rate			=  ic ->streams[videostream] ->codec->bit_rate;
    		st->codec->width			=  ic ->streams[videostream] ->codec->width;
    		st->codec->height			=  ic ->streams[videostream] ->codec->height;
    		st->codec->gop_size			=  ic ->streams[videostream] ->codec->gop_size;
    		st->codec->pix_fmt			=  ic ->streams[videostream] ->codec->pix_fmt;
    		st->codec->frame_size		=  ic ->streams[videostream] ->codec->frame_size;
    		st->codec->has_b_frames		=  ic ->streams[videostream] ->codec->has_b_frames;
    		st->codec->extradata		=  ic ->streams[videostream] ->codec->extradata;
    		st->codec->extradata_size	=  ic ->streams[videostream] ->codec->extradata_size;
    		st->codec->codec_tag		=  ic ->streams[videostream] ->codec->codec_tag;
    		st->codec->bits_per_raw_sample		=  ic ->streams[videostream] ->codec->bits_per_raw_sample;
    		st->codec->chroma_sample_location	=  ic ->streams[videostream] ->codec->chroma_sample_location;
    		st->time_base.den			=  ic ->streams[videostream] ->time_base.den;
    		st->time_base.num			=  ic ->streams[videostream] ->time_base.num;
    		st->cur_dts					=  ic ->streams[videostream] ->cur_dts;
    		st->stream_copy				=  1;
    		st->pts.den					=  ic ->streams[videostream] ->time_base.den;
    		st->pts.num					=  ic ->streams[videostream] ->time_base.num;
    		if( oc ->oformat->flags & AVFMT_GLOBALHEADER)
    			st ->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
    		if(av_q2d(ic ->streams[videostream] ->codec->time_base)*ic ->streams[videostream] ->codec->ticks_per_frame > av_q2d(ic ->streams[videostream]->time_base) && 
    			av_q2d(ic ->streams[videostream]->time_base) < 1.0/1000)
    		{
    			st->codec->time_base = ic ->streams[videostream] ->codec->time_base;
    			st->codec->time_base.num *= ic ->streams[videostream] ->codec->ticks_per_frame;
    		}
    		else
    		{
    			st->codec->time_base = ic ->streams[videostream] ->time_base;
    		}
    		st->disposition				=  ic ->streams[videostream] ->disposition;
    	}
    	if(audiostream >= 0 )
    	{
    		AVStream * st = av_new_stream( oc, audiostream);
    		if(!st)
    		{
    			printf("can not add a audio stream.\n");
    			return -4;
    		}
    		st->codec->codec_id			=  ic ->streams[audiostream] ->codec->codec_id;
    		st->codec->codec_type		=  CODEC_TYPE_AUDIO;
    		st->codec->bit_rate			=  ic ->streams[audiostream] ->codec->bit_rate;
    		st->codec->gop_size			=  ic ->streams[audiostream] ->codec->gop_size;
    		st->codec->pix_fmt			=  ic ->streams[audiostream] ->codec->pix_fmt;
    		st->codec->bit_rate			=  ic ->streams[audiostream] ->codec->bit_rate;
    		st->codec->channel_layout	=  ic ->streams[audiostream] ->codec->channel_layout;
    		st->codec->frame_size		=  ic ->streams[audiostream] ->codec->frame_size;
    		st->codec->sample_rate		=  ic ->streams[audiostream] ->codec->sample_rate;
    		st->codec->channels			=  ic ->streams[audiostream] ->codec->channels;	
    		st->codec->block_align		=  ic ->streams[audiostream] ->codec->block_align;	
    		st->time_base.den			=  ic ->streams[audiostream] ->time_base.den;
    		st->time_base.num			=  ic ->streams[audiostream] ->time_base.num;
    		st->stream_copy				=  1;
    		st->pts.den					=  ic ->streams[audiostream] ->time_base.den;
    		st->pts.num					=  ic ->streams[audiostream] ->time_base.num;
    		if( oc->oformat->flags & AVFMT_GLOBALHEADER)
    			st ->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
    		if(av_q2d(ic ->streams[audiostream] ->codec->time_base)*ic ->streams[audiostream] ->codec->ticks_per_frame > av_q2d(ic ->streams[audiostream]->time_base) && 
    			av_q2d(ic ->streams[audiostream]->time_base) < 1.0/1000)
    		{
    			st->codec->time_base = ic ->streams[audiostream] ->codec->time_base;
    			st->codec->time_base.num *= ic ->streams[audiostream] ->codec->ticks_per_frame;
    		}
    		else
    		{
    			st->codec->time_base = ic ->streams[audiostream] ->time_base;
    		}
    	}
    	/* set the output parameters (must be done even if no parameters). */
    	//AVFormatParameters params, *ap = ¶ms;
    	//memset(ap, 0, sizeof(*ap));
    	if (av_set_parameters(oc, NULL/*ap*/) < 0)
    	{
    		printf("invalid output format parameters.\n");
    		return -5;
    	}
    	oc ->flags |= AVFMT_FLAG_NONBLOCK;
    	/*******************************************init output contents end**********************************************************/
    
    	/* open the output file, if needed */
    	if (!(oc ->oformat ->flags & AVFMT_NOFILE)) 
    	{
    		try
    		{
    			if (url_fopen(&oc->pb, ofile, URL_WRONLY) < 0) 
    			{
    				printf("Could not open file.\n");
    				return -6;
    			}
    		}
    		catch(...)
    		{
    			printf("Could not open file.\n");
    			return -6;
    		}
    	}
    
    	/* write the stream header, if any */
    	if( 0 != av_write_header(oc))
    	{
    		printf("write the stream header failed.\n");
    		return -7;
    	}
    
    	return 0;
    }

转帖：http://blog.csdn.net/sloan6/article/details/8190638