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• how to change the frame rate and capturing image size from IP camera

  6 décembre 2015, par rockycai

  Now I have a IP camera and I want to capture image from it through RTSP.I use below code and it works well.But the camera’s frame rate is 25/s.So I got a lot of images per second.I don’t want it.And per image is 6.2MB.I also don’t want need to get high quality image.What can I do to slower the frame rate and smaller the size of image ?

  #ifndef INT64_C
  
  #define INT64_C(c) (c ## LL)
  
  #define UINT64_C(c) (c ## ULL)
  
  #endif
  
  
  
  #ifdef __cplusplus
  
  extern "C" {
  
  #endif
  
      /*Include ffmpeg header file*/
  
  #include <libavformat></libavformat>avformat.h>
  
  #include <libavcodec></libavcodec>avcodec.h>
  
  #include <libswscale></libswscale>swscale.h>
  
  #include 
  
  #ifdef __cplusplus
  
  }
  
  #endif
  
  
  
  #include 
  
  
  
  
  
  static void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame);
  
  
  
  int main (int argc, const char * argv[])
  
  {
  
      AVFormatContext *pFormatCtx;
  
      int             i, videoStream;
  
      AVCodecContext  *pCodecCtx;
  
      AVCodec         *pCodec;
  
      AVFrame         *pFrame; 
  
      AVFrame         *pFrameRGB;
  
      AVPacket        packet;
  
      int             frameFinished;
  
      int             numBytes;
  
      uint8_t         *buffer;
  
  
  
      // Register all formats and codecs
  
      av_register_all();
  
  //  const char *filename="C:\libraries\gfjyp.avi";
  
      // Open video file
  
      //AVDictionary *options = NULL;
  
      //av_dict_set(&amp;options,"rtsp_transport","tcp",0);
  
      if(av_open_input_file(&amp;pFormatCtx, argv[1], NULL, 0, NULL)!=0)
  
          return -1; // Couldn't open file
  
  
  
      // Retrieve stream information
  
      if(av_find_stream_info(pFormatCtx)&lt;0)
  
          return -1; // Couldn't find stream information
  
  
  
      // Dump information about file onto standard error
  
      dump_format(pFormatCtx, 0, argv[1], false);
  
  
  
      // Find the first video stream
  
      videoStream=-1;
  
      for(i=0; inb_streams; i++)
  
          if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO)
  
          {
  
              videoStream=i;
  
              break;
  
          }
  
          if(videoStream==-1)
  
              return -1; // Didn't find a video stream
  
  
  
          // Get a pointer to the codec context for the video stream
  
          pCodecCtx=pFormatCtx->streams[videoStream]->codec;
  
  
  
          // Find the decoder for the video stream
  
          pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
  
          if(pCodec==NULL)
  
              return -1; // Codec not found
  
  
  
          // Open codec
  
          if(avcodec_open(pCodecCtx, pCodec)&lt;0)
  
              return -1; // Could not open codec
  
  
  
          // Hack to correct wrong frame rates that seem to be generated by some codecs
  
  
  
          if(pCodecCtx->time_base.num>1000 &amp;&amp; pCodecCtx->time_base.den==1)
  
              pCodecCtx->time_base.den=1000;
  
  
  
          //pCodecCtx->time_base.den=1;
  
          //pCodecCtx->time_base.num=1;
  
          // Allocate video frame
  
          pFrame=avcodec_alloc_frame();
  
  
  
          // Allocate an AVFrame structure
  
          pFrameRGB=avcodec_alloc_frame();
  
          if(pFrameRGB==NULL)
  
              return -1;
  
  
  
          // Determine required buffer size and allocate buffer
  
          numBytes=avpicture_get_size(PIX_FMT_RGB24, pCodecCtx->width,
  
              pCodecCtx->height);
  
  
  
          //buffer=malloc(numBytes);
  
          buffer=(uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
  
  
  
          // Assign appropriate parts of buffer to image planes in pFrameRGB
  
          avpicture_fill((AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24,
  
              pCodecCtx->width, pCodecCtx->height);
  
  
  
          // Read frames and save first five frames to disk
  
          i=0;
  
          while(av_read_frame(pFormatCtx, &amp;packet)>=0)
  
          {
  
              // Is this a packet from the video stream?
  
              if(packet.stream_index==videoStream)
  
              {
  
                  // Decode video frame
  
                  avcodec_decode_video2(pCodecCtx, pFrame, &amp;frameFinished, 
  
                      &amp;packet);
  
  
  
                  // Did we get a video frame?
  
                  if(frameFinished)
  
                  {
  
  
  
                      static struct SwsContext *img_convert_ctx;
  
  
  
  #if 0
  
                      // Older removed code
  
                      // Convert the image from its native format to RGB swscale
  
                      img_convert((AVPicture *)pFrameRGB, PIX_FMT_RGB24, 
  
                          (AVPicture*)pFrame, pCodecCtx->pix_fmt, pCodecCtx->width, 
  
                          pCodecCtx->height);
  
  
  
                      // function template, for reference
  
                      int sws_scale(struct SwsContext *context, uint8_t* src[], int srcStride[], int srcSliceY,
  
                          int srcSliceH, uint8_t* dst[], int dstStride[]);
  
  #endif
  
                      // Convert the image into YUV format that SDL uses
  
                      if(img_convert_ctx == NULL) {
  
                          int w = pCodecCtx->width;
  
                          int h = pCodecCtx->height;
  
  
  
                          img_convert_ctx = sws_getContext(w, h, 
  
                              pCodecCtx->pix_fmt, 
  
                              w, h, PIX_FMT_RGB24, SWS_BICUBIC,
  
                              NULL, NULL, NULL);
  
                          if(img_convert_ctx == NULL) {
  
                              fprintf(stderr, "Cannot initialize the conversion context!\n");
  
                              exit(1);
  
                          }
  
                      }
  
                      int ret = sws_scale(img_convert_ctx, pFrame->data, pFrame->linesize, 0, 
  
                          pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
  
  #if 0 
  
                      // this use to be true, as of 1/2009, but apparently it is no longer true in 3/2009
  
                      if(ret) {
  
                          fprintf(stderr, "SWS_Scale failed [%d]!\n", ret);
  
                          exit(-1);
  
                      }
  
  #endif
  
  
  
                      // Save the frame to disk
  
                      if(i++&lt;=1000)
  
                          SaveFrame(pFrameRGB, pCodecCtx->width, pCodecCtx->height, i);
  
                  }
  
              }
  
  
  
              // Free the packet that was allocated by av_read_frame
  
              av_free_packet(&amp;packet);
  
              //sleep(1);
  
          }
  
  
  
          // Free the RGB image
  
          //free(buffer);
  
          av_free(buffer);
  
          av_free(pFrameRGB);
  
  
  
          // Free the YUV frame
  
          av_free(pFrame);
  
  
  
          // Close the codec
  
          avcodec_close(pCodecCtx);
  
  
  
          // Close the video file
  
          av_close_input_file(pFormatCtx);
  
  
  
          return 0;
  
  }
  
  
  
  static void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame)
  
  {
  
      FILE *pFile;
  
      char szFilename[32];
  
      int  y;
  
  
  
      // Open file
  
      sprintf(szFilename, "frame%d.ppm", iFrame);
  
      pFile=fopen(szFilename, "wb");
  
      if(pFile==NULL)
  
          return;
  
  
  
      // Write header
  
      fprintf(pFile, "P6\n%d %d\n255\n", width, height);
  
  
  
      // Write pixel data
  
      for(y=0; ydata[0]+y*pFrame->linesize[0], 1, width*3, pFile);
  
  
  
      // Close file
  
      fclose(pFile);
  
  }

• How to overlay swf files on a video

  17 décembre 2015, par Harsha Vardhan

  Hi recently I started working with ffmpeg, there I overlay-ed images as well as gif files on videos. Where coming to swf files ffmpeg is unable to recognize that format.

  I tried below command for overlaying :

  ffmpeg -i vid.mp4 -i swf.swf -filter_co
  
  mplex overlay=x=100:y=100:shortest=1  -q 15 -vcodec libx264 out.mp4
  
  ffmpeg version N-76822-g12a419d Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 5.2.0 (GCC)
  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
  
  isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
  
  le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
  
  enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-l
  
  ibilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enab
  
  le-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --en
  
  able-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --ena
  
  ble-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc
  
   --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enabl
  
  e-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --
  
  enable-lzma --enable-decklink --enable-zlib
  
    libavutil      55.  9.100 / 55.  9.100
  
    libavcodec     57. 16.100 / 57. 16.100
  
    libavformat    57. 19.100 / 57. 19.100
  
    libavdevice    57.  0.100 / 57.  0.100
  
    libavfilter     6. 15.100 /  6. 15.100
  
    libswscale      4.  0.100 /  4.  0.100
  
    libswresample   2.  0.101 /  2.  0.101
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'vid.mp4':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 1
  
      compatible_brands: mp42avc1
  
      creation_time   : 2009-03-02 14:42:39
  
    Duration: 00:00:10.56, start: 0.000000, bitrate: 663 kb/s
  
      Stream #0:0(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, flt
  
  p, 125 kb/s (default)
  
      Metadata:
  
        creation_time   : 2009-03-02 14:42:39
  
        handler_name    : Apple Sound Media Handler
  
      Stream #0:1(eng): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yu
  
  v420p(tv, smpte170m/smpte170m/bt709), 480x360, 196 kb/s, 24 fps, 24 tbr, 600 tbn
  
  , 1200 tbc (default)
  
      Metadata:
  
        creation_time   : 2009-03-02 14:42:40
  
        handler_name    : Apple Video Media Handler
  
      Stream #0:2(eng): Data: none (rtp  / 0x20707472), 202 kb/s
  
      Metadata:
  
        creation_time   : 2009-03-02 14:42:40
  
        handler_name    : hint media handler
  
      Stream #0:3(eng): Data: none (rtp  / 0x20707472), 129 kb/s
  
      Metadata:
  
        creation_time   : 2009-03-02 14:42:40
  
        handler_name    : hint media handler
  
  [swf @ 00000098cdb9e000] Could not find codec parameters for stream 0 (Audio: pc
  
  m_u8, 5512 Hz, mono, 44 kb/s): unspecified sample format
  
  Consider increasing the value for the 'analyzeduration' and 'probesize' options
  
  Input #1, swf, from 'swf.swf':
  
    Duration: 00:00:04.90, bitrate: 196 kb/s
  
      Stream #1:0: Audio: pcm_u8, 5512 Hz, mono, 44 kb/s
  
      Stream #1:1: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
      Stream #1:2: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
      Stream #1:3: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
      Stream #1:4: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
      Stream #1:5: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
      Stream #1:6: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
      Stream #1:7: Audio: mp3, 11025 Hz, mono, s16p, 16 kb/s
  
  Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_overlay
  
  _0

  Any one please suggest me, how to resolve this issue or even getting frames from swf format files by using ffmpeg or any other similar tools.

• format unknown error with ffmpeg

  6 février 2016, par Rambo Actionha

  I’m trying to convert .webm to .mp4 using :

  ffmpeg -fflags +genpts -i 1.webm -r 24 1.mp4

  it doesn’t work , this is what I get :

  C:\Users\mahmoud\Desktop\ffmpeg>ffmpeg -fflags +genpts -i v.webm -r 24 1.mp4
  
  FFmpeg version SVN-r18639, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  
    configuration: --enable-memalign-hack --enable-postproc --enable-gpl --enable-
  
  libfaac --enable-libfaad --enable-libgsm --enable-libmp3lame --enable-libvorbis
  
  --enable-libtheora --enable-libx264 --enable-libxvid --disable-ffserver --enable
  
  -avisynth --enable-pthreads
  
    libavutil     50. 3. 0 / 50. 3. 0
  
    libavcodec    52.27. 0 / 52.27. 0
  
    libavformat   52.32. 0 / 52.32. 0
  
    libavdevice   52. 2. 0 / 52. 2. 0
  
    libswscale     0. 7. 1 /  0. 7. 1
  
    libpostproc   51. 2. 0 / 51. 2. 0
  
    built on Apr 21 2009 13:44:38, gcc: 4.2.4 (TDM-1 for MinGW)
  
  v.webm: Unknown format

  any one can help ?