FFMPEG研究: ubuntu下录制/dev/video0/设备视频保存为mp4格式

学习参考，雷博系列文章：http://blog.csdn.net/column/details/ffmpeg-devel.html

1. 以下代码有详细注释，我就不写文字了。

2. 另外本代码今天刚刚移植完成，只实现了录制保存的功能，还有BUG和细节没有考虑，后面持续更新。

3. 本文章只贴出最新的代码，不保留以前版本的代码，需要的同学可以联系我要-QQ 1356438802。

4. 这个demo实际上是根据雷博的两个demo融合的，

最简单的基于FFmpeg的AVDevice例子（读取摄像头）/ 最简单的基于FFmpeg的视频编码器(YUV to h264)

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更新LOG（）：

v1.0-20150915: 刚刚移植完成，第一次上传。

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v1.0

/** * 最简单的基于FFmpeg的AVDevice例子（读取摄像头） * Simplest FFmpeg Device (Read Camera) * * 雷霄骅 Lei Xiaohua * [e-mail] * 中国传媒大学/数字电视技术 * Communication University of China / Digital TV Technology * http://blog.csdn.net/leixiaohua1020 * * 本程序实现了本地摄像头数据的获取解码和显示。是基于FFmpeg * 的libavdevice类库最简单的例子。通过该例子，可以学习FFmpeg中 * libavdevice类库的使用方法。 * 本程序在Windows下可以使用2种方式读取摄像头数据： *  1.VFW: Video for Windows 屏幕捕捉设备。注意输入URL是设备的序号， *          从0至9。 *  2.dshow: 使用Directshow。注意作者机器上的摄像头设备名称是 *         “Integrated Camera”，使用的时候需要改成自己电脑上摄像头设 *          备的名称。 * 在Linux下则可以使用video4linux2读取摄像头设备。 * * This software read data from Computer's Camera and play it. * It's the simplest example about usage of FFmpeg's libavdevice Library.  * It's suiltable for the beginner of FFmpeg. * This software support 2 methods to read camera in Microsoft Windows: *  1.gdigrab: VfW (Video for Windows) capture input device. *             The filename passed as input is the capture driver number, *             ranging from 0 to 9. *  2.dshow: Use Directshow. Camera's name in author's computer is  *             "Integrated Camera". * It use video4linux2 to read Camera in Linux. *  */#include "al_common.h"#define __STDC_CONSTANT_MACROS//Linux...#ifdef __cplusplusextern "C"{#endif#include <libavcodec/avcodec.h>#include <libavformat/avformat.h>#include <libswscale/swscale.h>#include <libavdevice/avdevice.h>#include <SDL/SDL.h>#ifdef __cplusplus};#endifstatic int flush_encoder(AVFormatContext *fmt_context, unsigned int stream_index);int main(int argc, char* argv[]){inti;intvideoindex;//输入视频流的序号AVFormatContext*pInFmtContext;//输入码流的上下文属性描述AVCodecContext*pInCodecContext;//输入视频流的编码信息AVCodec*pInCodec;//输入视频流需要的解码器AVInputFormat *input_fmt;//输入视频流格式AVFormatContext* pOutFmtContext;//输出码流的上下文属性描述AVCodecContext* pOutCodecContext;//输出视频流的编码信息AVCodec* pOutCodec;//输出视频流需要的编码器AVOutputFormat* output_fmt;//输出视频流格式AVStream* out_vd_stream;//AVStream是存储每一个视频/音频流信息的结构体AVPacket out_packet;//压缩数据包const char* out_file = "luo.mp4";av_register_all();//初始化所有的编解码器，复用解复用器avformat_network_init();//初始化流媒体网络相关协议//分配空间pInFmtContext = avformat_alloc_context();//分配空间pOutFmtContext = avformat_alloc_context();//初始化libavdevice库avdevice_register_all();    //寻找video4linux2的视频流输入格式 input_fmt = av_find_input_format("video4linux2");//根据输出文件名取得文件编码格式，也就是视频流输出格式output_fmt = av_guess_format(NULL, out_file, NULL);pOutFmtContext->oformat = output_fmt;/*根据input_fmt和设备文件"/dev/video0"初始化pInFmtContext码流可以理解为，pInFmtContext码流是从/dev/video0设备以ifmt的格式读出来的视频流，avformat_open_input第四个参数option是对input_fmt格式的操作，如分辨率；NULL——>不操作*/if(avformat_open_input(&pInFmtContext, "/dev/video0", input_fmt, NULL)!=0){printf("Couldn't open input stream.\n");return -1;}/*打开输出流out_file（与打开输入流类似）根据上面取得的output_fmt以及out_file的形式（可以是RMTP/UDP/TCP/file）初始化输出码流*/if (avio_open(&pOutFmtContext->pb, out_file, AVIO_FLAG_READ_WRITE) < 0){printf("Failed to open output file! \n");return -1;}//查询输入码流中的所有流信息if(avformat_find_stream_info(pInFmtContext,NULL)<0){printf("Couldn't find stream information.\n");return -1;}//寻找输入码流中的视频流，保存序号videoindexvideoindex=-1;for(i=0; i<pInFmtContext->nb_streams; i++) if(pInFmtContext->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){videoindex=i;break;}if(videoindex==-1){printf("Couldn't find a video stream.\n");return -1;}//在输出码流中新建一个视频流out_vd_stream = avformat_new_stream(pOutFmtContext, 0);out_vd_stream->time_base.num = 1; out_vd_stream->time_base.den = 25; if (out_vd_stream == NULL){return -1;}//取出输入视频流的编码信息pInCodecContext=pInFmtContext->streams[videoindex]->codec;LOGI("--line %d--in_w = %d\t in_h = %d't fmt = %d\n", __LINE__, pInCodecContext->width, pInCodecContext->height, pInCodecContext->pix_fmt);//根据编码信息里面的编码器ID，找到对应的解码器pInCodec=avcodec_find_decoder(pInCodecContext->codec_id);if(pInCodec==NULL){printf("Codec not found.\n");return -1;}//打开并初始化pInCodec解码器if(avcodec_open2(pInCodecContext, pInCodec,NULL)<0){printf("Could not open codec.\n");return -1;}LOGI("--line %d--in_w = %d\t in_h = %d't fmt = %d\n", __LINE__, pInCodecContext->width, pInCodecContext->height, pInCodecContext->pix_fmt);//获取视频流的编码信息存储地址，然后进行赋值初始化pOutCodecContext = out_vd_stream->codec;pOutCodecContext->codec_id = output_fmt->video_codec;//编码器IDpOutCodecContext->codec_type = AVMEDIA_TYPE_VIDEO;//IO流类型：视频流，音频流pOutCodecContext->pix_fmt = PIX_FMT_YUV420P;//视频流的帧格式pOutCodecContext->width = pInCodecContext->width;  //帧宽（使用输入视频流的帧宽）pOutCodecContext->height = pInCodecContext->height;//帧高（使用输入视频流的帧高）pOutCodecContext->time_base.num = 1;  pOutCodecContext->time_base.den = 25;  //设置帧率25pOutCodecContext->bit_rate = 400000;//比特率  pOutCodecContext->gop_size=250;//设置GOP大小：每250帧插入一个I帧//H264//pOutCodecContext->me_range = 16;//pOutCodecContext->max_qdiff = 4;//pOutCodecContext->qcompress = 0.6;pOutCodecContext->qmin = 10;pOutCodecContext->qmax = 51;//Optional Param//该值表示在两个非B帧之间，允许插入的B帧的最大帧数pOutCodecContext->max_b_frames=3;//Show some Information//将输出码流的信息显示到终端av_dump_format(pOutFmtContext, 0, out_file, 1);//根据解码器ID找到对应的解码器pOutCodec = avcodec_find_encoder(pOutCodecContext->codec_id);if (!pOutCodec){printf("Can not find encoder! \n");return -1;}//------------------------------------------------------------------------------//设置一些参数AVDictionary *param = 0;//H.264if(pOutCodecContext->codec_id == AV_CODEC_ID_H264) {av_dict_set(¶m, "preset", "slow", 0);av_dict_set(¶m, "tune", "zerolatency", 0);//av_dict_set(¶m, "profile", "main", 0);}//H.265if(pOutCodecContext->codec_id == AV_CODEC_ID_H265){av_dict_set(¶m, "preset", "ultrafast", 0);av_dict_set(¶m, "tune", "zero-latency", 0);}//打开并初始化pOutCodec解码器if (avcodec_open2(pOutCodecContext, pOutCodec, ¶m) < 0){printf("Failed to open encoder! \n");return -1;}//------------------------------------------------------------------------------/*存储：1. 原始数据（即非压缩数据，例如对视频来说是YUV，RGB，对音频来说是PCM）2. 帧信息*/AVFrame*pInFrame;//输入的视频流中取出来的视频帧AVFrame*pOutFrame;//转换成YUV420P格式后的视频帧//初始化帧pInFrame = av_frame_alloc();pOutFrame = av_frame_alloc();/*由于pInFrame是来自于视频流，解码函数会自动为其分配帧数据空间而pFrameYUV是转换格式后的帧，需要预先分配空间给它**注意:几乎所有的编码器编码用的数据源格式都必须是YUV420P，所以当视频设备取出来的帧格式不是这个格式时，需要用libswscale库来进行格式和分辨率的转换，至YUV420P之后，才能进行编码压缩。解码过程：AVStream --> AVPacket --> AVFrame（AVFrame是非压缩数据包，可直接用于显示）编码过程：AVFrame --> AVPacket --> AVStream*/int buf_size;uint8_t* out_buf;//avpicture_get_size(目标格式，目标帧宽，目标帧高)buf_size = avpicture_get_size(pOutCodecContext->pix_fmt, pOutCodecContext->width, pOutCodecContext->height);out_buf = (uint8_t *)av_malloc(buf_size);avpicture_fill((AVPicture *)pOutFrame, out_buf, pOutCodecContext->pix_fmt, pOutCodecContext->width, pOutCodecContext->height);int ret, got_picture;/*存储压缩编码数据相关信息的结构体。AVFrame是非压缩的*/AVPacket *in_packet=(AVPacket *)av_malloc(sizeof(AVPacket));//根据Frame大小，初始化一个Packetav_new_packet(&out_packet,buf_size);//往输出码流中写入headeravformat_write_header(pOutFmtContext,NULL);  /*libswscale是一个主要用于处理图片像素数据的类库。可以完成图片像素格式的转换，图片的拉伸等工作sws_getContext()：初始化一个SwsContext。sws_scale()：处理图像数据。sws_freeContext()：释放一个SwsContext。其中sws_getContext()也可以用sws_getCachedContext()取代。几乎“万能”的图片像素数据处理类库srcW：源图像的宽srcH：源图像的高srcFormat：源图像的像素格式dstW：目标图像的宽dstH：目标图像的高dstFormat：目标图像的像素格式flags：设定图像拉伸使用的算法成功执行的话返回生成的SwsContext，否则返回NULL。*/struct SwsContext *img_convert_context;//img_convert_context描述了两个格式转换的协议：格式、分辨率、转码算法...img_convert_context = sws_getContext(pInCodecContext->width, pInCodecContext->height, pInCodecContext->pix_fmt, pOutCodecContext->width, pOutCodecContext->height, pOutCodecContext->pix_fmt, SWS_BICUBIC, NULL, NULL, NULL); int pix_size;pix_size = pOutCodecContext->width * pOutCodecContext->height;//================================================int framenum=500;int framecnt=0;//Frames to encode 经过编码的有效帧数for (;;) {/*读取码流中的音频若干帧或者视频一帧。例如，解码视频的时候，每解码一个视频帧，需要先调用 av_read_frame()获得一个视频的压缩数据包，然后才能对该数据进行解码（例如H.264中一帧压缩数据通常对应一个NAL）。packet是压缩数据*/if(av_read_frame(pInFmtContext, in_packet)>=0){//如果该数据包是视频数据包，则进行视频解码if(in_packet->stream_index == videoindex){/*从packet压缩数据里取出一帧AVFrame非压缩数据输入一个压缩编码的结构体AVPacket，输出一个解码后的结构体AVFrame*/ret = avcodec_decode_video2(pInCodecContext, pInFrame, &got_picture, in_packet);if(ret < 0){LOGE("Decode Error.\n");av_free_packet(in_packet);continue;}//成功从输入视频流中解码出一帧数据if(got_picture){//转换帧格式sws_scale(img_convert_context, (const uint8_t* const*)pInFrame->data, pInFrame->linesize, 0, pInCodecContext->height, pOutFrame->data, pOutFrame->linesize);//PTS: 帧时间戳pOutFrame->pts = framecnt;framecnt++;if(framecnt > framenum){LOGE("framecnt > %d \n", framenum);av_free_packet(in_packet);break;}//开始压缩数据got_picture = 0;/*将帧编码成包：输入一个帧，输出一个包**注意:几乎所有的编码器编码用的数据源格式都必须是YUV420P，所以当视频设备取出来的帧格式不是这个格式时，需要用libswscale库来进行格式和分辨率的转换，至YUV420P之后，才能进行编码压缩。解码过程：AVStream --> AVPacket --> AVFrame（AVFrame是非压缩数据包，可直接用于显示）编码过程：AVFrame --> AVPacket --> AVStream*/ret = avcodec_encode_video2(pOutCodecContext, &out_packet, pOutFrame, &got_picture);if(ret < 0){LOGE("Failed to encode! \n");av_free_packet(in_packet);continue;}if (got_picture == 1){LOGI("Succeed to encode frame: %5d\tsize:%5d \tindex = %d\n", framecnt, out_packet.size, out_vd_stream->index);out_packet.stream_index = out_vd_stream->index;//标识该视频/音频流: 序号//将视频包写入到输出码流ret = av_write_frame(pOutFmtContext, &out_packet);//释放该包av_free_packet(&out_packet);}}}av_free_packet(in_packet);}else{break;}}//=========================================//将编码器中剩余的帧数据冲刷到输出码流中，即写入文件，防止丢失帧ret = flush_encoder(pOutFmtContext, 0);if (ret < 0) {LOGE("Flushing encoder failed\n");}LOGI("av_write_trailer\n");//往输出码流中写入tailav_write_trailer(pOutFmtContext);sws_freeContext(img_convert_context);//Cleanif (out_vd_stream){//关闭输出视频流的编码器avcodec_close(pOutCodecContext);//释放帧av_free(pOutFrame);//释放缓存av_free(out_buf);}//关闭输出视频流avio_close(pOutFmtContext->pb);//关闭输出码流avformat_free_context(pOutFmtContext);//av_free(out_buffer);av_free(pInFrame);//关闭输入视频流的解码器avcodec_close(pInCodecContext);//关闭输入码流avformat_close_input(&pInFmtContext);return 0;}static int flush_encoder(AVFormatContext *fmt_context, unsigned int stream_index){int ret;int got_picture;AVPacket enc_packet;if (!(fmt_context->streams[stream_index]->codec->codec->capabilities & CODEC_CAP_DELAY))return 0;while (1) {enc_packet.data = NULL;enc_packet.size = 0;av_init_packet(&enc_packet);ret = avcodec_encode_video2 (fmt_context->streams[stream_index]->codec, &enc_packet,NULL, &got_picture);av_frame_free(NULL);if (ret < 0)break;if (!got_picture){ret=0;break;}LOGI("Flush Encoder: Succeed to encode 1 frame!\tsize:%5d\n", enc_packet.size);/* mux encoded frame */ret = av_write_frame(fmt_context, &enc_packet);if (ret < 0)break;}return ret;}

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更新LOG（）：

v2.0-20151019: 

1. 经过之前2个星期的调试，终于能够稳定录制了。

2. v1.0版本的源码有变量空间释放，以及录制视频时间轴的问题。经过本人深入理解（但不一定正确哈，只是以格物致知的态度去求知而已），并且实验，一些内存空间的使用和释放有一定的规律，特别是AVFrame和AVpacket的变量空间。

3. 另外由于v1.0的av_write_frame，写入输出码流的packet没有正确加入时间戳，最后录制的视频没有时间轴，不能正常播放。在研读了FFMPEG官方示例muxing.c后，进行了相应的修改，v2.0版本录制的视频可以正常播放，帧数也正常。

4. 其他修改则是数据结构的一些优化。

5. 由于在不同的环境搞来搞去，字符集搞乱了，注释乱码，可以忽略。看v1.0的注释就可以了。

附上源码包，平台是ubuntu-64：链接：http://pan.baidu.com/s/1jvzPk 密码：ht2q

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v2.0

#include "record_camera.h"//Linux...#ifdef __cplusplusextern "C"{#endif#define STREAM_FRAME_RATE 25 // 25 fpsstatic struct RecordContext *gRecordContext;static int flush_encoder(AVFormatContext *fmt_context, unsigned int stream_index){int ret;int got_picture;AVPacket encode_packet;if (!(fmt_context->streams[stream_index]->codec->codec->capabilities & CODEC_CAP_DELAY))return 0;while (1) {encode_packet.data = NULL;encode_packet.size = 0;av_init_packet(&encode_packet);ret = avcodec_encode_video2 (fmt_context->streams[stream_index]->codec, &encode_packet,NULL, &got_picture);av_frame_free(NULL);if (ret < 0)break;if (!got_picture){ret=0;break;}LOGI("Flush Encoder: Succeed to encode 1 frame!\tsize:%5d\n", encode_packet.size);/* mux encoded frame */ret = av_write_frame(fmt_context, &encode_packet);if (ret < 0)break;}return ret;}int SetShowBufferAddr(uint8 *ShowBuffer){//��ʼ���Դ�if(NULL == ShowBuffer){return -1;}else{gRecordContext->ShowBuffer = ShowBuffer;}return 0;}int RecordInit(char *RecordFile, int IsShow){int i;int ret = -1;char file[24] = {0};AVDictionary *option = NULL;AVDictionary *param = NULL;gRecordContext = (struct RecordContext *)calloc(1, sizeof(struct RecordContext));ERROR(NULL == gRecordContext, err1, "calloc gRecordContext");//memset(gRecordContext, 0, sizeof(struct RecordContext));LOGI("RecordInit start\n");//��ʼ������ļ���if(RecordFile == NULL){LOGI("create a random file to record video\n");srand((unsigned)time(NULL));sprintf(file, "/storage/sdcard0/Download/0917-%d-%d.mp4", rand()%10, rand()%10);gRecordContext->out_file_name = file;}else{gRecordContext->out_file_name = RecordFile;}gRecordContext->FrameCount = 0;//��������Ч֡������gRecordContext->IsShow = IsShow;gRecordContext->device_name = "/dev/video0";av_register_all();//��ʼ�����еı�����������ý⸴����avformat_network_init();//��ʼ����ý���������Э��//����ռ�gRecordContext->pInFmtContext = avformat_alloc_context();//����ռ�gRecordContext->pOutFmtContext = avformat_alloc_context();ERROR(((gRecordContext->pInFmtContext == NULL) || (gRecordContext->pOutFmtContext == NULL)), err2, "avformat_alloc_context");//��ʼ��libavdevice��avdevice_register_all();    //Ѱ��video4linux2����Ƶ�������ʽgRecordContext->input_fmt = av_find_input_format("video4linux2");ERROR((gRecordContext->input_fmt == NULL), err3, "Couldn't av_find_input_format\n");//��������ļ���ȡ���ļ������ʽ��Ҳ������Ƶ�������ʽgRecordContext->output_fmt = av_guess_format(NULL, gRecordContext->out_file_name, NULL);gRecordContext->pOutFmtContext->oformat = gRecordContext->output_fmt;//------------------------------------------------------------------------------//����������Ƶ����һЩ����av_dict_set(&option, "video_size", "640x480", 0);//���÷ֱ���av_dict_set(&option, "pixel_format", "mjpeg", 0);//------------------------------------------------------------------------------/*����input_fmt���豸�ļ�"/dev/video0"��ʼ��pInFmtContext�����������Ϊ��pInFmtContext�����Ǵ�/dev/video0�豸��ifmt�ĸ�ʽ����������Ƶ����avformat_open_input���ĸ�����option�Ƕ�input_fmt��ʽ�IJ�������ֱ��ʣ�NULL����>������*/ret = access(gRecordContext->device_name, F_OK);ERROR(ret < 0, err3, "device is not exsist!\n")ret = avformat_open_input(&gRecordContext->pInFmtContext, "/dev/video0", gRecordContext->input_fmt, NULL);ERROR((ret != 0), err3, "Couldn't open input stream.\n");/*�������out_file��������������ƣ���������ȡ�õ�output_fmt�Լ�out_file����ʽ��������RMTP/UDP/TCP/file����ʼ���������*/ret = avio_open(&gRecordContext->pOutFmtContext->pb, gRecordContext->out_file_name, AVIO_FLAG_READ_WRITE);ERROR(ret < 0, err7, "Failed to open output file! \n");//��ѯ���������е���������Ϣret = avformat_find_stream_info(gRecordContext->pInFmtContext,NULL);ERROR(ret < 0, err8, "Couldn't find stream information.\n");//Ѱ�����������е���Ƶ�����������videoindexgRecordContext->videoindex = -1;for(i = 0; i < gRecordContext->pInFmtContext->nb_streams; i++){if(gRecordContext->pInFmtContext->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO){gRecordContext->videoindex = i;break;}}ERROR((gRecordContext->videoindex == -1), err9, "Couldn't find a video stream.\n");//������������½�һ����Ƶ��gRecordContext->out_vd_stream = avformat_new_stream(gRecordContext->pOutFmtContext, 0);ERROR((gRecordContext->out_vd_stream == NULL), err10, "avformat_new_stream");gRecordContext->out_vd_stream->time_base = (AVRational){1, STREAM_FRAME_RATE}; //ȡ��������Ƶ���ı�����ϢgRecordContext->pInCodecContext = gRecordContext->pInFmtContext->streams[gRecordContext->videoindex]->codec;LOGI("--line %d-- in_w = %d\t in_h = %d\t in_fmt = %d\t in_encode = %d\n",\__LINE__, gRecordContext->pInCodecContext->width, gRecordContext->pInCodecContext->height,\gRecordContext->pInCodecContext->pix_fmt, gRecordContext->pInCodecContext->codec_id);//���ݱ�����Ϣ����ı�����ID���ҵ���Ӧ�Ľ�����gRecordContext->pInCodec = avcodec_find_decoder(gRecordContext->pInCodecContext->codec_id);ERROR((gRecordContext->pInCodec == NULL), err11, "Codec not found.\n");//�⿪ү߽��ʼ��pInCodec������ret = avcodec_open2(gRecordContext->pInCodecContext, gRecordContext->pInCodec,NULL);ERROR(ret < 0, err12, "Could not open input codec.\n")LOGI("--line %d-- in_w = %d\t in_h = %d\t in_fmt = %d\t in_encode = %d\n",\__LINE__, gRecordContext->pInCodecContext->width, gRecordContext->pInCodecContext->height,\gRecordContext->pInCodecContext->pix_fmt, gRecordContext->pInCodecContext->codec_id);//��ȡ�����Ƶ���ı�����Ϣ�洢��ַ��Ȼ����и�ֵ��ʼ��gRecordContext->pOutCodecContext = gRecordContext->out_vd_stream->codec;gRecordContext->pOutCodecContext->codec_id = gRecordContext->output_fmt->video_codec;//������IDgRecordContext->pOutCodecContext->codec_type = AVMEDIA_TYPE_VIDEO;//IO�����ͣ���Ƶ������Ƶ��gRecordContext->pOutCodecContext->pix_fmt = PIX_FMT_YUV420P;//��Ƶ����֡��ʽgRecordContext->pOutCodecContext->width = gRecordContext->pInCodecContext->width;  //֡��ʹ��������Ƶ����֡��gRecordContext->pOutCodecContext->height = gRecordContext->pInCodecContext->height;//֡�ߣ�ʹ��������Ƶ����֡�ߣ�gRecordContext->pOutCodecContext->time_base = gRecordContext->out_vd_stream->time_base;gRecordContext->pOutCodecContext->bit_rate = 400000;//������gRecordContext->pOutCodecContext->gop_size=250;//����GOP��С��ÿ250֡����һ��I֡LOGI("--line %d-- out_w = %d\t out_h = %d\t out_fmt = %d\t out_encode = %d\n",\__LINE__, gRecordContext->pOutCodecContext->width, gRecordContext->pOutCodecContext->height,\gRecordContext->pOutCodecContext->pix_fmt, gRecordContext->pOutCodecContext->codec_id);//H264//pOutCodecContext->me_range = 16;//pOutCodecContext->max_qdiff = 4;//pOutCodecContext->qcompress = 0.6;gRecordContext->pOutCodecContext->qmin = 10;gRecordContext->pOutCodecContext->qmax = 51;//Optional Param//��ֵ��ʾ��������B֮֡�䣬��������B֡�����֡��gRecordContext->pOutCodecContext->max_b_frames=3;/* Some formats want stream headers to be separate. */    if (gRecordContext->pOutFmtContext->oformat->flags & AVFMT_GLOBALHEADER){LOGI("AVFMT_GLOBALHEADER\n");gRecordContext->pOutCodecContext->flags |= CODEC_FLAG_GLOBAL_HEADER;}        //Show some Information//�������������Ϣ��ʾ���նˡ�1,��ʾ�������; 0, ��ʾ��������av_dump_format(gRecordContext->pOutFmtContext, 0, gRecordContext->out_file_name, 1);//���ݽ�����ID�ҵ���Ӧ�Ľ�����gRecordContext->pOutCodec = avcodec_find_encoder(gRecordContext->pOutCodecContext->codec_id);ERROR(!gRecordContext->pOutCodec, err13, "Can not find encoder! \n");//------------------------------------------------------------------------------//����һЩ����//H.264if(gRecordContext->pOutCodecContext->codec_id == AV_CODEC_ID_H264) {av_dict_set(¶m, "preset", "slow", 0);av_dict_set(¶m, "tune", "zerolatency", 0);av_dict_set(¶m, "profile", "main", 0);}//H.265if(gRecordContext->pOutCodecContext->codec_id == AV_CODEC_ID_H265){av_dict_set(¶m, "preset", "ultrafast", 0);av_dict_set(¶m, "tune", "zero-latency", 0);}//20150929LOGI("extradata_size = %d\n", gRecordContext->pOutCodecContext->extradata_size);if(gRecordContext->pOutCodecContext->extradata_size > 0){printf_array(gRecordContext->pOutCodecContext->extradata, gRecordContext->pOutCodecContext->extradata_size);}//�⿪ү߽��ʼ��pOutCodec������if (avcodec_open2(gRecordContext->pOutCodecContext, gRecordContext->pOutCodec, ¶m) < 0){LOGE("Failed to open encoder! \n");return -1;}//20150929LOGI("extradata_size = %d\n", gRecordContext->pOutCodecContext->extradata_size);if(gRecordContext->pOutCodecContext->extradata_size > 0){printf_array(gRecordContext->pOutCodecContext->extradata, gRecordContext->pOutCodecContext->extradata_size);}//------------------------------------------------------------------------------//��ʼ��֡gRecordContext->pInFrame = av_frame_alloc();//avpicture_get_size(Ŀ���ʽ��Ŀ��֡��Ŀ��֡��)gRecordContext->InFrameBufSize = avpicture_get_size(gRecordContext->pInCodecContext->pix_fmt,\gRecordContext->pInCodecContext->width, gRecordContext->pInCodecContext->height);LOGI("ShowBufferSize = InFrameBufSize = %d\n", gRecordContext->InFrameBufSize);gRecordContext->ShowBufferSize = gRecordContext->InFrameBufSize;gRecordContext->pOutFrame = av_frame_alloc();/*����pInFrame����������Ƶ�������뺯�����Զ�Ϊ�����֡���ݿռ���pOutFrame��ת����ʽ���֡����ҪԤ�ȷ���ռ����**ע��:�������еı����������õ�����Դ��ʽ��������YUV420P�����Ե���Ƶ�豸ȡ������֡��ʽ���������ʽʱ����Ҫ��libswscale�������и�ʽ�ͷֱ��ʵ�ת������YUV420P֮�㣬ү߽�ܽ��б���ѹ����������̣�AVStream --> AVPacket --> AVFrame��AVFrame�Ƿ�ѹ�����ݰ�����ֱ��������ʾ��������̣�AVFrame --> AVPacket --> AVStream*///avpicture_get_size(Ŀ���ʽ��Ŀ��֡��Ŀ��֡��)gRecordContext->OutFrameBufSize = avpicture_get_size(gRecordContext->pOutCodecContext->pix_fmt,\gRecordContext->pOutCodecContext->width, gRecordContext->pOutCodecContext->height);LOGI("OutFrameBufSize = %d\n", gRecordContext->OutFrameBufSize);gRecordContext->OutFrameBuffer = (uint8_t *)av_malloc(gRecordContext->OutFrameBufSize);avpicture_fill((AVPicture *)gRecordContext->pOutFrame, gRecordContext->OutFrameBuffer, gRecordContext->pOutCodecContext->pix_fmt,\gRecordContext->pOutCodecContext->width, gRecordContext->pOutCodecContext->height);/*�洢ѹ���������������Ϣ�Ľṹ�塣AVFrame�Ƿ�ѹ����*/gRecordContext->in_packet = (AVPacket *)av_malloc(sizeof(AVPacket));//Be care full of these: av_new_packet should be callgRecordContext->out_packet = (AVPacket *)av_malloc(sizeof(AVPacket)); //20150918av_new_packet(gRecordContext->out_packet, gRecordContext->OutFrameBufSize);//20150918//img_convert_context������������ʽת����Э�飺��ʽ���ֱ��ʡ�ת���㷨...gRecordContext->img_convert_context = sws_getContext(gRecordContext->pInCodecContext->width,\gRecordContext->pInCodecContext->height, gRecordContext->pInCodecContext->pix_fmt,\gRecordContext->pOutCodecContext->width, gRecordContext->pOutCodecContext->height,\gRecordContext->pOutCodecContext->pix_fmt, SWS_BICUBIC, NULL, NULL, NULL); gRecordContext->pix_size = gRecordContext->pOutCodecContext->width * gRecordContext->pOutCodecContext->height;//�����������д��headeravformat_write_header(gRecordContext->pOutFmtContext,NULL);LOGI("RecordInit end\n");return gRecordContext->ShowBufferSize;err1:return -1;err2:LOGI("err2 11111\n");FREE(gRecordContext);LOGI("err2 22222\n");return -1;err3:LOGI("err3 11111\n");avformat_free_context(gRecordContext->pOutFmtContext);avformat_free_context(gRecordContext->pInFmtContext);FREE(gRecordContext);LOGI("err3 22222\n");return -1;err7:err8:err9:err10:err11:err12:err13:LOGI("err3 11111\n");avformat_close_input(&gRecordContext->pInFmtContext);avformat_free_context(gRecordContext->pOutFmtContext);avformat_free_context(gRecordContext->pInFmtContext);FREE(gRecordContext);LOGI("err3 22222\n");return -1;}int Recording(void){int ret = -1;int got_picture = -1;LOGI("Recording start\n");/*��ȡ�����е���Ƶ����֡������Ƶһ֡�����磬������Ƶ��ʱ��ÿ����һ����Ƶ֡����Ҫ�ȵ��� av_read_frame()���һ����Ƶ��ѹ�����ݰ���Ȼ����ܶԸ����ݽ��н��루����H.264��һ֡ѹ������ͨ����Ӧһ��NAL����packet��ѹ������*/ret = av_read_frame(gRecordContext->pInFmtContext, gRecordContext->in_packet);if(ret >= 0){LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);//��������ݰ�����Ƶ���ݰ����������Ƶ����if(gRecordContext->in_packet->stream_index == gRecordContext->videoindex){LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);/*��packetѹ��������ȡ��һ֡AVFrame��ѹ����������һ��ѹ������Ľṹ��AVPacket�����һ�������Ľṹ��AVFrame*/ret = avcodec_decode_video2(gRecordContext->pInCodecContext, gRecordContext->pInFrame, &got_picture, gRecordContext->in_packet);if(ret < 0){LOGE("Decode Error.\n");av_free_packet(gRecordContext->in_packet);return -1;}LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);//�ɹ���������Ƶ���н����һ֡����if(got_picture == 1){LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);if(1 == gRecordContext->IsShow){//��������Ƶ��������ͼƬ������apk���Դ�memcpy(gRecordContext->ShowBuffer, (const uint8_t* const*)gRecordContext->pInFrame->data, gRecordContext->ShowBufferSize);}LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);//ת��֡��ʽsws_scale(gRecordContext->img_convert_context, (const uint8_t* const*)gRecordContext->pInFrame->data, gRecordContext->pInFrame->linesize, 0, gRecordContext->pInCodecContext->height, gRecordContext->pOutFrame->data, gRecordContext->pOutFrame->linesize);LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);//PTS: ֡ʱ���gRecordContext->pOutFrame->pts = gRecordContext->FrameCount;gRecordContext->FrameCount++;if (gRecordContext->pOutFmtContext->oformat->flags & AVFMT_RAWPICTURE){LOGI("raw picture\n");}//��ʼѹ������got_picture = 0;av_init_packet(gRecordContext->out_packet);/*��֡����ɰ�������һ��֡�����һ����**ע��:�������еı����������õ�����Դ��ʽ��������YUV420P�����Ե���Ƶ�豸ȡ������֡��ʽ���������ʽʱ����Ҫ��libswscale�������и�ʽ�ͷֱ��ʵ�ת������YUV420P֮�㣬ү߽�ܽ��б���ѹ����������̣�AVStream --> AVPacket --> AVFrame��AVFrame�Ƿ�ѹ�����ݰ�����ֱ��������ʾ��������̣�AVFrame --> AVPacket --> AVStream*/ret = avcodec_encode_video2(gRecordContext->pOutCodecContext, gRecordContext->out_packet, gRecordContext->pOutFrame, &got_picture);if(ret < 0){LOGE("Failed to encode! \n");av_free_packet(gRecordContext->in_packet);return -1;}LOGI("lines= %d\tfunc = %s, frame count: %5d\n", __LINE__, __func__, gRecordContext->FrameCount);if (got_picture == 1){LOGI("Succeed to encode frame: %5d\tsize:%5d \tindex = %d\n", gRecordContext->FrameCount, gRecordContext->out_packet->size, gRecordContext->out_vd_stream->index);LOGI("before rescale: PTS = %d\t DTS = %d\n", gRecordContext->out_packet->pts, gRecordContext->out_packet->dts);LOGI("before rescale: duration = %d\t convergence_duration = %d\n", gRecordContext->out_packet->duration, gRecordContext->out_packet->convergence_duration);//重要！！！！时间戳av_packet_rescale_ts(gRecordContext->out_packet, gRecordContext->pOutCodecContext->time_base, gRecordContext->out_vd_stream->time_base);LOGI("after rescale: PTS = %d\t DTS = %d\n", gRecordContext->out_packet->pts, gRecordContext->out_packet->dts);LOGI("after rescale: duration = %d\t convergence_duration = %d\n", gRecordContext->out_packet->duration, gRecordContext->out_packet->convergence_duration);gRecordContext->out_packet->stream_index = gRecordContext->out_vd_stream->index;//��ʶ����Ƶ/��Ƶ��: ���//����Ƶ��д�뵽�������ret = av_write_frame(gRecordContext->pOutFmtContext, gRecordContext->out_packet);//�ͷŸð�av_free_packet(gRecordContext->out_packet);}}}av_free_packet(gRecordContext->in_packet);}LOGI("Recording end\n");return 0;}static int printf_array(uint8_t *array, int size){int i;for(i = 0; i < size; i++){printf("0x%x  ", *(array + i));}printf("\n");}int RecordUninit(void){int ret = -1;LOGI("RecordUninit start\n");//=========================================//����������ʣ���֡���ݳ�ˢ����������У���д���ļ�����ֹ��ʧ֡ret = flush_encoder(gRecordContext->pOutFmtContext, gRecordContext->out_vd_stream->index);if (ret < 0) {LOGE("Flushing encoder failed\n");}LOGI("av_write_trailer\n");//�����������д��tailav_write_trailer(gRecordContext->pOutFmtContext);sws_freeContext(gRecordContext->img_convert_context);//Cleanif (gRecordContext->out_vd_stream){//�ر������Ƶ���ı�����avcodec_close(gRecordContext->pOutCodecContext);//�ͷ�֡av_frame_free(&gRecordContext->pOutFrame);//�ͷŰ�av_free(gRecordContext->out_packet);//�ͷŻ���av_free(gRecordContext->OutFrameBuffer);}//�ر������Ƶ��avio_close(gRecordContext->pOutFmtContext->pb);//�ر��������avformat_free_context(gRecordContext->pOutFmtContext);//�ͷ�֡av_frame_free(&gRecordContext->pInFrame);//�ͷŰ�//av_free_packet(gRecordContext->in_packet);av_free(gRecordContext->in_packet);//�ر�������Ƶ���Ľ�����avcodec_close(gRecordContext->pInCodecContext);//�ر���������avformat_close_input(&gRecordContext->pInFmtContext);avformat_free_context(gRecordContext->pInFmtContext);FREE(gRecordContext);LOGI("RecordUninit end\n");return 0;}#ifdef __cplusplus};#endif