• windows下使用FFmpeg开源库进行视频编解码完整步聚

    最终解码效果:

    1.UI设计

     2.在控件属性窗口中输入默认值

    3.复制已编译FFmpeg库到工程同级目录下

     4.在工程引用FFmpeg库及头文件

     

    5.链接指定FFmpeg库

     

    6.使用FFmpeg库

    引用头文件 

    1. extern "C"
    2. {
    3. #include "libswscale/swscale.h"
    4. #include "libavdevice/avdevice.h"
    5. #include "libavcodec/avcodec.h"
    6. #include "libavcodec/bsf.h"
    7. #include "libavformat/avformat.h"
    8. #include "libavutil/avutil.h"
    9. #include "libavutil/imgutils.h"
    10. #include "libavutil/log.h"
    11. #include "libavutil/imgutils.h"
    12. #include "libavutil/time.h"
    13. #include 
    14.  
    15. }

    创建视频编解码管理类 

    实现视频编解码管理类

    1. #include "ffmpegmananger.h"
    2. #include 
    3. ffmpegMananger::ffmpegMananger(QObject *parent ):
    4.     QObject(parent)
    5. {
    6.     m_pInFmtCtx = nullptr;
    7.     m_pTsFmtCtx  = nullptr;
    8.     m_qstrRtspURL = "";
    9.     m_qstrOutPutFile = "";
    10. }
    11. ffmpegMananger::~ffmpegMananger()
    12. {
    13.     avformat_free_context(m_pInFmtCtx);
    14.     avformat_free_context(m_pTsFmtCtx);
    15. }
    16.  
    17. void ffmpegMananger::getRtspURL(QString strRtspURL)
    18. {
    19.     this->m_qstrRtspURL = strRtspURL;
    20. }
    21. void ffmpegMananger::getOutURL(QString strRute)
    22. {
    23.     this->m_qstrOutPutFile = strRute;
    24.     printf("===========%s\n",m_qstrOutPutFile.toStdString().c_str());
    25. }
    26. void ffmpegMananger::setOutputCtx(AVCodecContext *encCtx, AVFormatContext **pTsFmtCtx,int &nVideoIdx_out)
    27. {
    28.     avformat_alloc_output_context2(pTsFmtCtx , nullptr, nullptr, m_qstrOutPutFile.toStdString().c_str());
    29.     if (!pTsFmtCtx ) {
    30.         printf("Could not create output context\n");
    31.         return;
    32.     }
    33.     if (avio_open(&((*pTsFmtCtx)->pb), m_qstrOutPutFile.toStdString().c_str(), AVIO_FLAG_READ_WRITE) < 0)
    34.     {
    35.        avformat_free_context(*pTsFmtCtx);
    36.        printf("avio_open fail.");
    37.        return;
    38.     }
    39.     AVStream *out_stream = avformat_new_stream(*pTsFmtCtx, encCtx->codec);
    40.     nVideoIdx_out = out_stream->index;
    41.     //nVideoIdx_out = out_stream->index;
    42.     avcodec_parameters_from_context(out_stream->codecpar, encCtx);
    43.     printf("==========Output Information==========\n");
    44.     av_dump_format(*pTsFmtCtx, 0, m_qstrOutPutFile.toStdString().c_str(), 1);
    45.     printf("======================================\n");
    46. }
    47. int ffmpegMananger::ffmepgInput()
    48. {
    49.     int nRet = 0;
    50.     AVCodecContext *encCtx = nullptr;//编码器
    51.     //const char *pUrl = "D:/videos/264.dat";
    52.     std::string temp = m_qstrRtspURL.toStdString();
    53.     const char *pUrl = temp.c_str();
    54.     printf("===========%s\n",pUrl);
    55.     AVDictionary *options = nullptr;
    56.     av_dict_set(&options,"rtsp_transport", "tcp", 0);
    57.     av_dict_set(&options,"stimeout","10000000",0);
    58.     // 设置“buffer_size”缓存容量
    59.     av_dict_set(&options, "buffer_size", "1024000", 0);
    60.     nRet = avformat_open_input(&m_pInFmtCtx,pUrl,nullptr,&options);
    61.     if( nRet < 0)
    62.     {
    63.         printf("Could not open input file,===========keep trying \n");
    64.         return nRet;
    65.     }
    66.     avformat_find_stream_info(m_pInFmtCtx, nullptr);
    67.     printf("===========Input Information==========\n");
    68.     av_dump_format(m_pInFmtCtx, 0, pUrl, 0);
    69.     printf("======================================\n");
    70.     //1.获取视频流编号
    71.     int nVideo_indx = av_find_best_stream(m_pInFmtCtx,AVMEDIA_TYPE_VIDEO,-1,-1,nullptr,0);
    72.     if(nVideo_indx < 0)
    73.     {
    74.         avformat_free_context(m_pInFmtCtx);
    75.         printf("查找解码器失败\n");
    76.         return -1;
    77.     }
    78.     //2.查找解码器
    79.     AVCodec *pInCodec = avcodec_find_decoder(m_pInFmtCtx->streams[nVideo_indx]->codecpar->codec_id);
    80.     if(nullptr == pInCodec)
    81.     {
    82.         printf("avcodec_find_decoder fail.");
    83.         return -1;
    84.     }
    85.     //获取解码器上下文
    86.     AVCodecContext* pInCodecCtx = avcodec_alloc_context3(pInCodec);
    87.     //复制解码器参数
    88.     nRet = avcodec_parameters_to_context(pInCodecCtx, m_pInFmtCtx->streams[nVideo_indx]->codecpar);
    89.     if(nRet < 0)
    90.     {
    91.  
    92.         avcodec_free_context(&pInCodecCtx);
    93.         printf("avcodec_parameters_to_context fail.");
    94.         return -1;
    95.     }
    96.     //打开解码器
    97.     if(avcodec_open2(pInCodecCtx, pInCodec, nullptr) < 0)
    98.     {
    99.         avcodec_free_context(&pInCodecCtx);
    100.         printf("Error: Can't open codec!\n");
    101.         return -1;
    102.     }
    103.     printf("width = %d\n", pInCodecCtx->width);
    104.     printf("height = %d\n", pInCodecCtx->height);
    105.     int frame_index = 0;
    106.     int got_picture = 0;
    107.     AVStream *in_stream =nullptr;
    108.     AVStream *out_stream =nullptr;
    109.     AVFrame *pFrame= av_frame_alloc();
    110.     AVPacket *newpkt = av_packet_alloc();
    111.     AVPacket *packet = av_packet_alloc();
    112.     av_init_packet(newpkt);
    113.     av_init_packet(packet);
    114.     // alloc AVFrame
    115.     AVFrame*pFrameRGB = av_frame_alloc();
    116.     // 图像色彩空间转换、分辨率缩放、前后图像滤波处理
    117.     SwsContext *m_SwsContext = sws_getContext(pInCodecCtx->width, pInCodecCtx->height,
    118.             pInCodecCtx->pix_fmt, pInCodecCtx->width, pInCodecCtx->height,
    119.             AV_PIX_FMT_RGB32, SWS_BICUBIC, nullptr, nullptr, nullptr);
    120.  
    121.     int bytes = av_image_get_buffer_size(AV_PIX_FMT_RGB32, pInCodecCtx->width, pInCodecCtx->height,4);
    122.     uint8_t *m_OutBuffer = (uint8_t *)av_malloc(bytes * sizeof(uint8_t));
    123.  
    124.     // 将分配的内存空间给pFrameRGB使用
    125.     avpicture_fill((AVPicture *)pFrameRGB, m_OutBuffer, AV_PIX_FMT_RGB32, pInCodecCtx->width, pInCodecCtx->height);
    126.     if(encCtx == nullptr)
    127.     {
    128.         //打开编码器
    129.         openEncoder(pInCodecCtx->width, pInCodecCtx->height,&encCtx);
    130.     }
    131.     int videoindex_out = 0;
    132.     //设置输出文件上下文
    133.     setOutputCtx(encCtx,&m_pTsFmtCtx,videoindex_out);
    134.     //Write file header
    135.     if (avformat_write_header(m_pTsFmtCtx, nullptr) < 0)
    136.     {
    137.         avformat_free_context(m_pTsFmtCtx);
    138.         printf("Error occurred when opening output file\n");
    139.         return -1;
    140.     }
    141.     printf("==============writer trail===================.\n");
    142.     int count = 0;
    143.     nRet = 0;
    144.     while(av_read_frame(m_pInFmtCtx, packet) >= 0)//从pInFmtCtx读H264数据到packet；
    145.     {
    146.         if(packet->stream_index != nVideo_indx)//仅保留图像
    147.         {
    148.             continue;
    149.         }
    150.         if(avcodec_send_packet(pInCodecCtx, packet)<0)//送packet中H264数据给解码器码器进行解码，解码好的YUV数据放在pInCodecCtx,
    151.         {
    152.            break;
    153.         }
    154.         av_packet_unref(packet);
    155.         got_picture = avcodec_receive_frame(pInCodecCtx, pFrame);//把解码好的YUV数据放到pFrame中
    156.         if(0 == got_picture)//解码好一帧数据
    157.         {
    158.             //发送显示图像的信号
    159.             // 对解码视频帧进行缩放、格式转换等操作
    160.             sws_scale(m_SwsContext, (uint8_t const * const *)pFrame->data,
    161.                      pFrame->linesize, 0, pInCodecCtx->height,
    162.                      pFrameRGB->data, pFrameRGB->linesize);
    163.  
    164.             // 转换到QImage
    165.             QImage tmmImage((uchar *)m_OutBuffer, pInCodecCtx->width, pInCodecCtx->height, QImage::Format_RGB32);
    166.             QImage image = tmmImage.copy();
    167.  
    168.             // 发送QImage
    169.             emit Sig_GetOneFrame(image);
    170.  
    171.             setDecoderPts(newpkt->stream_index,count, pFrame);
    172.             count++;
    173.             //送原始数据给编码器进行编码
    174.             nRet = avcodec_send_frame(encCtx,pFrame);
    175.             if(nRet < 0)
    176.             {
    177.                 continue;
    178.             }
    179.             //从编码器获取编号的数据
    180.             while(nRet >= 0)
    181.             {
    182.                 nRet = avcodec_receive_packet(encCtx,newpkt);
    183.                 if(nRet < 0)
    184.                 {
    185.                     break;
    186.                 }
    187.                 setEncoderPts(nVideo_indx,frame_index,videoindex_out,newpkt);
    188.                 int _count = 1;
    189.                 printf("Write %d Packet. size:%5d\tpts:%lld\n", _count,newpkt->size, newpkt->pts);
    190.  
    191.                 if (av_interleaved_write_frame(m_pTsFmtCtx, newpkt) < 0)
    192.                 {
    193.                     printf("Error muxing packet\n");
    194.                     goto end;
    195.                 }
    196.                 _count++;
    197.                 av_packet_unref(newpkt);
    198.             }
    199.         }
    200.     }
    201.     while(1)//从pInFmtCtx读H264数据到packet；
    202.     {
    203.         if(packet->stream_index != nVideo_indx)//仅保留图像
    204.         {
    205.             continue;
    206.         }
    207.         if(avcodec_send_packet(pInCodecCtx, packet)<0)//送packet中H264数据给解码器码器进行解码，解码好的YUV数据放在pInCodecCtx,
    208.         {
    209.             continue;
    210.         }
    211.         av_packet_unref(packet);
    212.         got_picture = avcodec_receive_frame(pInCodecCtx, pFrame);//把解码好的YUV数据放到pFrame中
    213.         if(!got_picture)//解码好一帧数据
    214.         {
    215.             AVRational in_time_base1 = in_stream->time_base;
    216.             in_stream = m_pInFmtCtx->streams[newpkt->stream_index];
    217.  
    218.             //Duration between 2 frames (us)
    219.             int64_t in_duration = (double)AV_TIME_BASE / av_q2d(in_stream->r_frame_rate);
    220.             pFrame->pts = (double)(count*in_duration) / (double)(av_q2d(in_time_base1)*AV_TIME_BASE);
    221.             count++;
    222.             //送原始数据给编码器进行编码
    223.             nRet = avcodec_send_frame(encCtx,pFrame);
    224.             if(nRet < 0)
    225.             {
    226.                 break;
    227.             }
    228.             //从编码器获取编号的数据
    229.             while(nRet >= 0)
    230.             {
    231.                 nRet = avcodec_receive_packet(encCtx,newpkt);
    232.                 if(nRet < 0)
    233.                 {
    234.                     continue;
    235.                 }
    236.                 in_stream = m_pInFmtCtx->streams[newpkt->stream_index];
    237.                 out_stream = m_pTsFmtCtx->streams[videoindex_out];
    238.                 if (newpkt->stream_index == nVideo_indx)
    239.                 {
    240.                     //FIX：No PTS (Example: Raw H.264)
    241.                     //Simple Write PTS
    242.                     if (newpkt->pts == AV_NOPTS_VALUE)
    243.                     {
    244.                         //Write PTS
    245.                         AVRational time_base1 = in_stream->time_base;
    246.                         //Duration between 2 frames (us)
    247.                         int64_t calc_duration = (double)AV_TIME_BASE / av_q2d(in_stream->r_frame_rate);
    248.                         //Parameters
    249.                         newpkt->pts = (double)(frame_index*calc_duration) / (double)(av_q2d(time_base1)*AV_TIME_BASE);
    250.                         newpkt->dts = newpkt->pts;
    251.                         newpkt->duration = (double)calc_duration / (double)(av_q2d(time_base1)*AV_TIME_BASE);
    252.                         frame_index++;
    253.                     }
    254.                  }
    255.                 //Convert PTS/DTS
    256.                 newpkt->pts = av_rescale_q_rnd(newpkt->pts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
    257.                 newpkt->dts = av_rescale_q_rnd(newpkt->dts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
    258.                 newpkt->duration = av_rescale_q(newpkt->duration, in_stream->time_base, out_stream->time_base);
    259.                 newpkt->pos = -1;
    260.                 newpkt->stream_index = videoindex_out;
    261.                 int count = 1;
    262.                 printf("Write %d Packet. size:%5d\tpts:%lld\n", count,newpkt->size, newpkt->pts);
    263.  
    264.                 if (av_interleaved_write_frame(m_pTsFmtCtx, newpkt) < 0)
    265.                 {
    266.                     printf("Error muxing packet\n");
    267.                     goto end;
    268.                 }
    269.                 count++;
    270.                 av_packet_unref(newpkt);
    271.             }
    272.         }
    273.     }
    274.     //Write file trailer
    275.     av_write_trailer(m_pTsFmtCtx);
    276. end:
    277.     av_frame_free(&pFrame);
    278.     av_frame_free(&pFrameRGB);
    279.     av_packet_unref(newpkt);
    280.     av_packet_unref(packet);
    281.     std::cout<<"rtsp's h264 to ts end";  
    282.     return  0;
    283. }
    284. void ffmpegMananger::setDecoderPts(int idx,int count,AVFrame *pFrame)
    285. {
    286.     AVStream* in_stream = m_pInFmtCtx->streams[idx];
    287.     AVRational in_time_base1 = in_stream->time_base;
    288.     //Duration between 2 frames (us)
    289.     int64_t in_duration = (double)AV_TIME_BASE / av_q2d(in_stream->r_frame_rate);
    290.     pFrame->pts = (double)(count*in_duration) / (double)(av_q2d(in_time_base1)*AV_TIME_BASE);
    291. }
    292. void ffmpegMananger::setEncoderPts(int nVideo_indx,int frame_index,int videoindex_out,AVPacket *newpkt)
    293. {
    294.     AVStream*in_stream = m_pInFmtCtx->streams[newpkt->stream_index];
    295.     AVStream*out_stream = m_pTsFmtCtx->streams[videoindex_out];
    296.     if (newpkt->stream_index == nVideo_indx)
    297.     {
    298.         //FIX：No PTS (Example: Raw H.264)
    299.         //Simple Write PTS
    300.         if (newpkt->pts == AV_NOPTS_VALUE)
    301.         {
    302.             //Write PTS
    303.             AVRational time_base1 = in_stream->time_base;
    304.             //Duration between 2 frames (us)
    305.             int64_t calc_duration = (double)AV_TIME_BASE / av_q2d(in_stream->r_frame_rate);
    306.             //Parameters
    307.             newpkt->pts = (double)(frame_index*calc_duration) / (double)(av_q2d(time_base1)*AV_TIME_BASE);
    308.             newpkt->dts = newpkt->pts;
    309.             newpkt->duration = (double)calc_duration / (double)(av_q2d(time_base1)*AV_TIME_BASE);
    310.             frame_index++;
    311.         }
    312.      }
    313.     //Convert PTS/DTS
    314.     newpkt->pts = av_rescale_q_rnd(newpkt->pts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
    315.     newpkt->dts = av_rescale_q_rnd(newpkt->dts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
    316.     newpkt->duration = av_rescale_q(newpkt->duration, in_stream->time_base, out_stream->time_base);
    317.     newpkt->pos = -1;
    318.     newpkt->stream_index = videoindex_out;
    319. }
    320. void ffmpegMananger::writeTail()
    321. {
    322.     //Write file trailer
    323.     av_write_trailer(m_pTsFmtCtx);
    324. }
    325. void ffmpegMananger::openEncoder(int width, int height, AVCodecContext** enc_ctx)
    326. {
    327.     //使用libx264编码器
    328.     AVCodec * pCodec = avcodec_find_encoder_by_name("libx264");
    329.     if(nullptr == pCodec)
    330.     {
    331.         printf("avcodec_find_encoder_by_name fail.\n");
    332.         return;
    333.     }
    334.     //获取编码器上下文
    335.     *enc_ctx = avcodec_alloc_context3(pCodec);
    336.     if(nullptr == enc_ctx)
    337.     {
    338.         printf("avcodec_alloc_context3(pCodec) fail.\n");
    339.         return;
    340.     }
    341.     //sps/pps
    342.     (*enc_ctx)->profile = FF_PROFILE_H264_MAIN;
    343.     (*enc_ctx)->level = 30;//表示level是5.0
    344.     //分辨率
    345.     (*enc_ctx)->width = width;
    346.     (*enc_ctx)->height = height;
    347.     //gop
    348.     (*enc_ctx)->gop_size = 25;//i帧间隔
    349.     (*enc_ctx)->keyint_min = 20;//设置最小自动插入i帧的间隔.OPTION
    350.     //B帧
    351.     (*enc_ctx)->max_b_frames = 0;//不要B帧
    352.     (*enc_ctx)->has_b_frames = 0;//
    353.     //参考帧
    354.     (*enc_ctx)->refs = 3;//OPTION
    355.     //设置输入的yuv格式
    356.     (*enc_ctx)->pix_fmt = AV_PIX_FMT_YUV420P;
    357.     //设置码率
    358.     (*enc_ctx)->bit_rate = 3000000;
    359.     //设置帧率
    360.     //(*enc_ctx)->time_base = (AVRational){1,25};//帧与帧之间的间隔
    361.     (*enc_ctx)->time_base.num = 1;
    362.     (*enc_ctx)->time_base.den = 25;
    363.     //(*enc_ctx)->framerate = (AVRational){25,1};//帧率 25帧每秒
    364.     (*enc_ctx)->framerate.num = 25;
    365.     (*enc_ctx)->framerate.den = 1;
    366.     if(avcodec_open2((*enc_ctx),pCodec,nullptr) < 0)
    367.     {
    368.         printf("avcodec_open2 fail.\n");
    369.     }
    370.     return;
    371. }
    372.

     

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  • 原文地址：https://blog.csdn.net/fittec/article/details/134042078