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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);
  
  }

• Class FFMPEG not found on Webfaction

  28 janvier 2016, par Luan Gabriel

  I’m trying to use FFMPEG on my application but its no working. The FFMPEG its install in my server (WebFaction) :

  FFmpeg version UNKNOWN, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration : —enable-gpl —enable-libamr-nb —enable-libamr-wb —enable-libfaac —enable-libfaad —enable-libmp3lame —enable-nonfree
  libavutil 49.14. 0 / 49.14. 0
  libavcodec 52.15. 0 / 52.15. 0
  libavformat 52.28. 0 / 52.28. 0
  libavdevice 52. 1. 0 / 52. 1. 0
  built on Jan 9 2015 12:30:52, gcc : 4.8.2 20140120 (Red Hat 4.8.2-16)

  But when I tried to do $mov = new ffmpeg_movie($movie); its showing me a error message : Class 'ffmpeg_movie' not found(...)

  Any ideas ?

• php exec ffmpeg how to get errors

  20 mars 2016, par Wiika

  exec("ffmpeg -i $flv -y -f mjpeg -ss 00:00:05 -s 120x90 -vframes 1 -an thumb.jpg",$error);

  $error return’s empty value
  but when i run this command using cron job
  this one send a notification email to me which contain informations like

  FFmpeg version 0.5.2, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration : —prefix=/usr —libdir=/usr/lib64 —shlibdir=/usr/lib64 —mandir=/usr/share/man —incdir=/usr/include —disable-avisynth —extra-cflags=-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector —param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC —enable-avfilter —enable-avfilter-lavf —enable-libdirac —enable-libfaac —enable-libfaad —enable-libfaadbin —enable-libmp3lame —enable-libopencore-amrnb —enable-libopencore-amrwb —enable-libtheora —enable-libx264 —enable-gpl —enable-nonfree —enable-postproc —enable-pthreads —enable-shared —enable-swscale —enable-vdpau —enable-version3 —enable-x11grab
  libavutil 49.15. 0 / 49.15. 0
  libavcodec 52.20. 1 / 52.20. 1
  libavformat 52.31. 0 / 52.31. 0
  libavdevice 52. 1. 0 / 52. 1. 0
  libavfilter 0. 4. 0 / 0. 4. 0
  libswscale 0. 7. 1 / 0. 7. 1
  libpostproc 51. 2. 0 / 51. 2. 0
  built on Jun 13 2010 23:44:18, gcc : 4.1.2 20080704 (Red Hat 4.1.2-48)

  I need to be able to get those errors in php so i can know if the thumb was created or not

  Thanks.