title: Checking keyframe interval?
body: <p>How can I check keyframe interval of a video file?</p>
  
  <p>all I can see in ffmpeg output is:</p>
  
  <pre><code>  Metadata:
      metadatacreator : Yet Another Metadata Injector for FLV - Version 1.8
      hasKeyframes    : true
      hasVideo        : true
      hasAudio        : true
      hasMetadata     : true
      canSeekToEnd    : true
      datasize        : 256600272
      videosize       : 210054362
      audiosize       : 45214634
      lasttimestamp   : 5347
      lastkeyframetimestamp: 5347
      lastkeyframelocation: 256649267
    Duration: 01:29:07.24, start: 0.040000, bitrate: 383 kb/s
      Stream #0:0: Video: h264 (High), yuv420p, 720x304 [SAR 1:1 DAR 45:19], 312 kb/s, 25 tbr, 1k tbn, 50 tbc
      Stream #0:1: Audio: mp3, 44100 Hz, mono, s16p, 64 kb/s
  </code></pre>