title: Why PTS and DTS are same in my stream?
body: <p>I am testing a mp4 file with H264 video using ffprobe.
  I am using the following command to get frame information.</p>
  
  <pre><code>ffprobe -i &lt;input_mp4_file&gt; -show_frames -select_streams v
  </code></pre>
  
  <p>I get the following output.</p>
  
  <pre><code>[FRAME]
  media_type=video
  stream_index=0
  key_frame=1
  pkt_pts=0
  pkt_pts_time=0.000000
  pkt_dts=0
  pkt_dts_time=0.000000
  best_effort_timestamp=0
  best_effort_timestamp_time=0.000000
  pkt_duration=512
  pkt_duration_time=0.033333
  pkt_pos=48
  pkt_size=513516
  width=1920
  height=1920
  pix_fmt=yuv420p
  sample_aspect_ratio=1:1
  pict_type=I
  coded_picture_number=0
  display_picture_number=0
  interlaced_frame=0
  top_field_first=0
  repeat_pict=0
  [/FRAME]
  [FRAME]
  media_type=video
  stream_index=0
  key_frame=0
  pkt_pts=512
  pkt_pts_time=0.033333
  pkt_dts=512
  pkt_dts_time=0.033333
  best_effort_timestamp=512
  best_effort_timestamp_time=0.033333
  pkt_duration=512
  pkt_duration_time=0.033333
  pkt_pos=513564
  pkt_size=3299
  width=1920
  height=1920
  pix_fmt=yuv420p
  sample_aspect_ratio=1:1
  pict_type=P
  coded_picture_number=1
  display_picture_number=0
  interlaced_frame=0
  top_field_first=0
  repeat_pict=0
  [/FRAME]
  [FRAME]
  media_type=video
  stream_index=0
  key_frame=0
  pkt_pts=1024
  pkt_pts_time=0.066667
  pkt_dts=1024
  pkt_dts_time=0.066667
  best_effort_timestamp=1024
  best_effort_timestamp_time=0.066667
  pkt_duration=512
  pkt_duration_time=0.033333
  pkt_pos=823989
  pkt_size=40971
  width=1920
  height=1920
  pix_fmt=yuv420p
  sample_aspect_ratio=1:1
  pict_type=B
  coded_picture_number=4
  display_picture_number=0
  interlaced_frame=0
  top_field_first=0
  repeat_pict=0
  [/FRAME]
  [FRAME]
  media_type=video
  stream_index=0
  key_frame=0
  pkt_pts=1536
  pkt_pts_time=0.100000
  pkt_dts=1536
  pkt_dts_time=0.100000
  best_effort_timestamp=1536
  best_effort_timestamp_time=0.100000
  pkt_duration=512
  pkt_duration_time=0.033333
  pkt_pos=784312
  pkt_size=38785
  width=1920
  height=1920
  pix_fmt=yuv420p
  sample_aspect_ratio=1:1
  pict_type=B
  coded_picture_number=3
  display_picture_number=0
  interlaced_frame=0
  top_field_first=0
  repeat_pict=0
  [/FRAME]
  [FRAME]
  media_type=video
  stream_index=0
  key_frame=0
  pkt_pts=2048
  pkt_pts_time=0.133333
  pkt_dts=2048
  pkt_dts_time=0.133333
  best_effort_timestamp=2048
  best_effort_timestamp_time=0.133333
  pkt_duration=512
  pkt_duration_time=0.033333
  pkt_pos=516886
  pkt_size=267344
  width=1920
  height=1920
  pix_fmt=yuv420p
  sample_aspect_ratio=1:1
  pict_type=P
  coded_picture_number=2
  display_picture_number=0
  interlaced_frame=0
  top_field_first=0
  repeat_pict=0
  [/FRAME]
  </code></pre>
  
  <p>My mp4 file has I, P and B frames. I understand that DTS is decode time stamp and it will be in incrementing order in decoder input stream. PTS is presentation time stamp and it will be in incrementing order in decoder output stream. </p>
  
  <p>I do not understand why I am getting same PTS and DTS values for all frames. I think they should be different when B frames are present in the stream.</p>
  
  <p>Somebody please help me in understanding this?</p>