Just Curious…avi vs wmv

[John Rofrano]

> I noticed that both projects used the same amount of space on a DVD, how could this be?

This is because DVD Architect re-encoded them to MPEG-2 which is the only format allowed on a DVD. So the DVD does not contain WMV or uncompressed… it contains MPEG-2.

> Also, I hear people often remark that WMV files are highly compressed and not good for burning, but when watching a WMV file compared to an uncompressed AVI, I don’t notice any difference, or any quality loss as a result of export from vegas. Again… how could his be?

Don’t confuse compression entirely with quality. Quality has a lot of components, one of which is determined by the bit-rate (i.e., having enough bits to represent the scene). If the WMV file had enough bits to represent all of the details in the scene, it should look about the same as the uncompressed video. If a scene only needs 1Mbps to accurately represent the detail, it doesn’t matter if you encode it at 1Mbps, 3Mbps WMV or uncompressed, you still have plenty of bits to represent the scene. It’s when you have a lot of detail (like running water) that you’ll really see a difference if the bit-rate isn’t high enough.

As for the final DVD, the MPEG-2 on the DVD is also highly compressed (about 25:1 compared to DV video which is about 5:1). If the WMV file was compressed less than the MPEG-2 file then it was still higher quality. There is just no reason to render to WMV which is a PC/web format when going to DVD. Render directly to MPEG-2 to maintain the highest quality.

~jr

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