V5 reverse audio buggy - clicks and pops

ibliss wrote on 5/16/2004, 1:34 AM

This is really sucks, can anyone verify that this is a repeatable and not just my system?

When I reverse a wav file on the timeline, it plays back flawlessly.

When I reverse a wma file on the timeline it plays back with various clicks and pops, which are also rendered. Depending on where the playback head starts, the clicks will occur at different points, but ALWAYS in the same place if you always start playback from the same place.

It looks like this compressed format is causing the problem, but it's a burden on my workflow as I keep my sfx collection in wma format for storage space reason. Now I will have to convert any sounds I am using in a project to WAV just in case I use the reverse funtion on it.

Any fix for this Sony guys?

Thanks

Comments

SonyTSW wrote on 5/16/2004, 9:57 AM

We'll take a look at this, thanks for letting us know.

Which particular WMA audio format are you using? This information may help us reproduce the problem.

ibliss wrote on 5/16/2004, 11:11 AM

Thanks for taking time to reply on a Sunday!

Ok, you should be able to replicate by doing this:

In soundforge (I have version 6) create a new file, then use the tone generation tool to create a 100Hz tone for 20 seconds (frequency and time are not critical, but I find 100hz easy on the ears and you need a few seconds of sample time to hear the clicking).

Save in WMA format at 128kb

open in Vegas

Reverse the clip

start playback and you should here giltches approximately every 1.20 seconds. You can zoom in on the wave form and see the glitches in the sine wave where a few samples have been dropped. The clicks will seem to get louder/worse then quieter because of the phasing of the errors against the frequency of the sine wave.

MP3 files seems to be fine, Wave files seem to be fine (all tests at 16/44.1)

For the record, I first noticed the problem using wma files created with Windows media player, digitally extracted from CD, though I think the above rules out Media player as the source of the problem.

My system: AMD A64 3000+, 512MB ram, Emu 1820M soundcard, WinXP SP1, Vegas 5a build 134, direct X version 9a

ibliss wrote on 5/18/2004, 4:08 PM

Anyone replicate this behaviour?

SonyTSW wrote on 5/18/2004, 9:07 PM

Yes, I was able to reproduce this behavior and logged it into our bug database.

As a workaround, you'll need to render to WAV or some other format that doesn't exhibit this problem. If you want to minimize file size, you might want to try the Perfect Clarity Audio (PCA) format, it's a lossless compression format.

ibliss wrote on 5/19/2004, 1:19 AM

Thanks TSW