Noise spikes in mpeg file created from dat file

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Hello Everyone,

I am a novice so please bear with me.

I had a VideoCD that was created on a Terrapin encoder. The VCD plays back fine on the Terrapin and plays fine in Windows using Windows Media Player.

I converted the VCD *.dat file to an mpeg file using vcdgear and it seemed to convert okay. The problem I am having is that there are intermittent (about one every 2 minutes or so) high frequency noise spikes. It's a very short high amplitude, high freqency blip that was not in the original track. I tried re-creating the mpeg to make sure it wasn't a one time glitch but the blips are in the same spots in the mpeg file.

I also tried using tmpgenc to convert it from an mpeg to another mpeg hoping that it might filter out the audio spikes but they are still there.

Man I am lost. Any suggestions or hints would be helpful.

Some info. => file is 696MB, about 1 hour long

Any questions just ask.

Thanks in advance for your help.

-- Nuke (jchumley@entrodyne.com), May 10, 2002

Answers

If it were possible I'd go and check out the original video source that was fed into the Terrapin; there is a possibility these noise spikes might have comes from there. If this was the case no amount of tweaking can remove them in the MPEG stream.

-- Mehmet Tekdemir (turk690@yahoo.com), May 11, 2002.

If the noise spikes were on the original media then wouldn't they be audible on the VCD? That's what confuses me. The VCD plays fine with no noise spikes. I'd appreciate help from anyone.

-- Nuke (jchumley@entrodyne.com), May 12, 2002.

This seems to happen when a conversion from 48kHz to 44.1kHz (cd- quality) takes place. WHatever does the conversion is apparently buggy. That's my best guess.

Tell me if that helped.

-- (remove the randomly inserted 'Z' characters - SPAM protection) (vksZgenZeric@hotZmaZil.com), May 14, 2002.


Are you saying that the VCD was at 48kHz?

What I did was go back and have another VCD made from the same source and I attempted to convert the VCD *.dat file to MPEG again. This time it worked with no glitches.

I am using a Terrapin VCD recorder. Anybody have any experience with whether the Terrapin might be the source of the noise and whether this is something that happens often.

I also am wondering why the noise was intermittent and why I couldn't hear the noise on the original VCD? If the VCD is in 48kHz and your experience is that the convertor sometimes has problems when converting 48kHz to 44kHz, what do you suggest that will allow me to prevent these on future conversions. I am using VCDGear but I am not really fluent on the features. Is there a feature that I can select which would prevent this problem during the conversion?

-- Nuke (jchumley@entrodyne.com), May 15, 2002.


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