title: Reading encoded data using muxing in ffmpeg
body: <p>I am trying to read an encoded video using ffmpeg c++. When I try to build my code error appears as identifier options is undefined. But it is already defined as  <code>AVDictionary *options = NULL</code>. </p>
  
  <p>What is wrong with my code?</p>
  
  <pre><code>void CFfmpegmethods::VideoRead(){
  
      const char *url = "H:/Sanduni_projects/ad_2.mp4";
  
      AVFormatContext *s = NULL;
      int ret = avformat_open_input(&amp;s, url, NULL, NULL);
      if (ret &lt; 0)
          abort();
  
      avformat_find_stream_info(s, &amp;options);
  
      AVDictionary *options = NULL;
  
      av_dict_set(&amp;options, "video_size", "640x480", 0);
      av_dict_set(&amp;options, "pixel_format", "rgb24", 0);
  
      if (avformat_open_input(&amp;s, url, NULL, &amp;options) &lt; 0){
          abort();
      }
  
      av_dict_free(&amp;options);
  
      AVDictionaryEntry *e;
  
      if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
          fprintf(stderr, "Option %s not recognized by the demuxer.\n", e-&gt;key);
          abort();
      }
  
      avformat_close_input(&amp;s);
  }
  </code></pre>