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• ffmpeg c/c++ get frame count or timestamp and fps

  23 juin 2016, par broschb

  I am using ffmpeg to decode a video file in C. I am struggling to get either the count of the current frame I am decoding or the timestamp of the frame. I have read numerous posts that show how to calculate an estimated frame no based on the fps and frame timestamp, however I am not able to get either of those.

  What I need : fps of video file, timestamp of current frame or frame no(not calculated)

  What I have : I am able to get the time of the video using

  pFormatCtx->duration/AV_TIME_BASE

  I am counting the frames currently as I process them, and getting a current frame count, this is not going to work longterm though. I can get the total frame count for the file using

  pFormatCtx->streams[currentStream->videoStream]->nb_frames

  I have read this may not work for all streams, although it has worked for every stream I have tried.

  I have tried using the time_base.num and time_base.den values and packet.pts, but I can’t make any sense of the values that I am getting from those, so I may just need to understand better what those values are.

  Does anyone know of resources that show examples on how to get this values ?

• Unable to execute CLI commands through PHP

  13 janvier 2012, par user940154

  OS : ubuntu 11.10
  Webserver : Apache
  Code : PHP
  I am trying to display the output of command "ffmpeg -i " on the webpage using php.
  Required : The webpage should show the information about video (text).
  Whats happening : The webpage shows no text output on running the php code.
  If I was however doing system("ls") the code runs fine and outputs the list of files.
  Here's my code

  <?php
  
   echo "Details of video file:";
  
   system('ffmpeg -i /home/atish/Videos/T2V0040006_Angled_ride_720x576i_FLDCMB.avi');
  
  ?>

  The same command works fine on my shell, and my system has ffmpeg installed. Here's a snapshot of executing this command directly on shell :

  ThinkPad-T420:~/Videos$ ffmpeg -i /home/xx/Videos/T2V0040006_Angled_ride_720x576i_FLDCMB.avi
  
  ffmpeg version git-2012-01-10-7e2ba2d Copyright (c) 2000-2012 the FFmpeg developers
  
  built on Jan 10 2012 12:01:19 with gcc 4.6.1
  
  configuration: --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-    amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab
  
    libavutil      51. 34.100 / 51. 34.100
  
    libavcodec     53. 54.100 / 53. 54.100
  
    libavformat    53. 29.100 / 53. 29.100
  
    libavdevice    53.  4.100 / 53.  4.100
  
    libavfilter     2. 58.100 /  2. 58.100
  
    libswscale      2.  1.100 /  2.  1.100
  
    libswresample   0.  6.100 /  0.  6.100
  
    libpostproc    51.  2.100 / 51.  2.100
  
    Input #0, avi, from '/home/atish/Videos/T2V0040006_Angled_ride_720x576i_FLDCMB.avi':
  
    Metadata:
  
    encoder         : Lavf52.23.1
  
    Duration: 00:00:29.00, start: 0.000000, bitrate: 124422 kb/s
  
    Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 720x576, 25 tbr, 25 tbn, 25 tbc
  
    At least one output file must be specified

  I have tried appending "DISPLAY=:0" to my command and also done "xhost +" before running php code, but nothing is helping me out.

  Thanks.

• FFMPEG in android issue

  9 janvier 2012, par Antu

  I have successfully compiled the FFMPEG library to android using NDK.
  (using Rock Player FFMPEG implementation)http://www.rockplayer.com/download/rockplayer_ffmpeg_git_20100418.zip

  I know that FFMPEG supports .avi, divX, mov ect. But I created a mediaplayer and tried to run them but I was not able to play them. I is this the right way to use the FFMPEG library. Can Any one Help.I am able to play defaut video, mp4, 3gp etc. Here is the code for mediaplayer

     public native String  stringFromJNI();
  
        static {
  
           System.loadLibrary("ffmpeg");
  
           System.loadLibrary("ffmpeg-test-jni");
  
               }
  
      @Override
  
        public void onCreate(Bundle savedInstanceState) {
  
        super.onCreate(savedInstanceState);
  
  
  
  
  
      setContentView(R.layout.main);
  
  
  
      TextView  tv =(TextView) findViewById(R.id.textView1);
  
      tv.setText( stringFromJNI() );
  
  
  
  
  
      System.gc();
  
  
  
      Log.d("Video FFmpeg ", "**");
  
  
  
      getWindow().setFormat(PixelFormat.TRANSLUCENT);
  
      String filepath = Environment.getExternalStorageDirectory()+"/simple.avi";
  
  
  
      Log.d("File path", filepath);
  
  
  
      MediaController mc = new MediaController(this); 
  
  
  
      VideoView video=(VideoView) findViewById(R.id.video);
  
      mc.setMediaPlayer(video);
  
      video.setVideoPath(filepath);
  
      video.setMediaController(mc);
  
      mc.show();
  
      //video.setVideoPath("/mnt/sdcard/Movies/Ishq-Hothon-Se.3gp");
  
  
  
      video.start();     
  
      View nextButton = findViewById(R.id.button1);
  
      nextButton.setOnClickListener(this);
  
      }
  
  
  
  
  
  
  
    @Override
  
    public void onClick(View v) {
  
    // TODO Auto-generated method stub
  
    Intent i=new Intent(this,NextVideo.class);
  
     startActivity(i);
  
  
  
    }
  
  
  
    }