MPEG file is 4 seconds longer

[JHL]

I am trying to encode HDTV bitrate MPEG-2 at an acceptable bitrate for DVD. Everything seems to work fine, but I noticed that the output file is mysteriously 4 seconds shorter that the original file. What happened?

Original: 1 hour 2 minutes 1 second
New file: 1 hour 1 minute 57 seconds

This is making it awfully difficult to synchronize the audio.

[b00zed]

Is it significant that the ratio between your two times is 30:29.97?

[Dimmer]

Just a guess: the original length is in non-drop frame timecode format, and the new length is in drop frame timecode format. This would mean that the number of frames remained the same, you simply have to change the authoring software settings.

[JHL]

Where is non-drop frame timecode available as an option? I could not find anything related to timecodes in the settings. I am trying to sychronize the MPEG audio/video BEFORE authoring the DVD, isn't that the easiest way to do that?

[Dimmer]

Originally posted by JHL
Where is non-drop frame timecode available as an option? I could not find anything related to timecodes in the settings. I am trying to sychronize the MPEG audio/video BEFORE authoring the DVD, isn't that the easiest way to do that? Well, how do you synchronize audio and video? Do you multiplex them into .mpg file? Whatever program you're using, it might have some settings related to the timecodes.

There is also a program around called Pulldown that allows to change drop frame flag within .m2v header without re-encoding.