Encoding Shortens Video
by Michael D. Brown
on
Jan 14, 2008 at 4:56:44 pm
Running CS3
I have a short credit list that runs about 30 seconds. The MPEG was created by Sorenson 4.5. Encore wants to transcode this video - it usually doesn't transcode these files.
After transcoding, the video is now about 24 seconds; the sound track remains 30 seconds. Not a good thing.
Check project reveals "trims and/or chapters adjusted"
I appreciate any advice.
Mike Brown
Video/Film Producer
American Heart Association
Re: Encoding Shortens Video by Michael D. Brown on Jan 14, 2008 at 6:23:17 pm
Hi Jeff!
MPEG 2 Elementary; 2-pass VBR
MAX: 7812 AVG: 5859 MIN: 3735
720 X 480 NTSC UNCONSTRAINED
29.97, 4:3, LOWER FIELD
I FRAMES: 15; P FRAMES: 3; AUTO GOP: NONE (other options are "fast" & "vcsd")
Audio is just an ordinary 48k/16 .wav file exported from the Avid.
I may try a 1-pass CBR to see if that fixes things.
Thanks for your fast reply.
Mike
Re: Encoding Shortens Video by Jeff Bellune on Jan 14, 2008 at 6:41:36 pm
[Michael D. Brown]"The MPEG was created by Sorenson 4.5. Encore wants to transcode this video - it usually doesn't transcode these files."
This is the statement that concerns me the most.
Did you start with one of the DVD presets in Squeeze?
There is a checkbox next to the "Auto GOP" drop-down box. It forces Squeeze to close the GOPs, which is better for use in Encore. Is that box checked?
Are you saying your source audio is 48KHz/16-bit, or that you exported from Squeeze as MPEG PCM audio? Squeeze's default (as you are probably aware) is to transcode the audio to MPEG Layer 2 audio, which is often a very bad choice for DVD.
Are you accidentally multiplexing the audio and video streams? If Encore gets a muxed program stream with audio that is not matched to the project audio settings, it will re-transcode the whole muxed file, audio *and* video.
Re: Encoding Shortens Video by Michael D. Brown on Jan 14, 2008 at 9:04:58 pm
Did you start with one of the DVD presets in Squeeze?
MB: Yes. It is a preset.
There is a checkbox next to the "Auto GOP" drop-down box.
MB: no checkbox... just the options "none/fast/vcsd."
Are you saying your source audio is 48KHz/16-bit, or that you exported from Squeeze as MPEG PCM audio?
MB: No. The .wav file is exported directly from Avid.
Squeeze's default (as you are probably aware) is to transcode the audio to MPEG Layer 2 audio, which is often a very bad choice for DVD.
MB: Squeeze doesn't touch the audio. Whatever Encore is doing, it affects only the video. The audio asset comes in as "Transcoded."
Are you accidentally multiplexing the audio and video streams?
MB: No, I looked at that... "DVD MPEG 2" format; elementary stream.
Thanks for the ideas. --MB
Solved for now, but a mystery by Michael D. Brown on Jan 14, 2008 at 9:23:37 pm
I was using a QT reference for Sorenson as I've always done before. This last time, I made a plain old QT movie - not a reference - for Sorenson to crunch. Encore seems happy with the result so I'm moving on. May be something weird with the original media. Always blame the Avid...
--Mike
