I edit the stuff i made wint ATI MMC8.1 in Vegas 4 and my question is, can i render a mpeg-2 in direct stream copy like virtual dub or i need to recompress the compressed stuff all the time???
The only time that Vegas can do a direct stream copy is if both the source and destination are uncompressed AVI or if both are DV AVI. If anything is different from this then the video will be decompressed and recompressed. Also, even if you do meet the above criteria, any sections with effects, compositing, fades, titles, etc. will also be decompressed and recompressed.
<little known fact>There are a select few AVI codecs that can also do direct stream copies, for example, some M-JPEG codecs. Since I haven't heard of the codec you mentioned, you might just have to try it. In particular, it cannot be a temporally compressed format.</little known fact>
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