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mp3dom
30th November 2005, 00:45
Hi to all,
sorry if this post could be a bit OT... It's quite "general" but involves a bit AviSynth.
Well, I have an MPEG 50 Mbps source (NTSC) that I'm converting to PAL via AviSynth (applying also some AviSynth filters) so at the end of all the process I'm in YUY2 colorspace (no colorspace conversion since here). To make post-production I need to make an Uncompressed RGB32 AVI (the NLE application supports only MPEG-50 Mpbs, Uncompressed AVI and AVI DV-50... and making post-production directly on the source NTSC causes a re-compression which lead to a lower quality). So my doubt is: It's better to append at the end of the AVS the "ConvertToRGB32()" or it's better to stay in YUY2 in the AVS and let VDubMod do the conversion (when I made the Uncompressed AVI)? Or the quality is the same in both cases? Clearly at the end I'm obliged to "reconvert" the final AVI to YUY2 colorspace to make the DVD mpeg encoding since I'm using a YUY2 mpeg encoder and TMPGEnc (which I think works in RGB) is quite poor in mpeg-2 quality compared to (i.e) CCE or ProCoder.
Thanks!

Wilbert
30th November 2005, 01:04
the NLE application supports only MPEG-50 Mpbs, Uncompressed AVI and AVI DV-50
Ok, i won't make any comment on the quality of this NLE.

It's better to append at the end of the AVS the "ConvertToRGB32()" or it's better to stay in YUY2 in the AVS and let VDubMod do the conversion (when I made the Uncompressed AVI)?
No, that doesn't matter.

TMPGEnc (which I think works in RGB)
True.

TMPGEnc is quite poor in mpeg-2 quality compared to (i.e) CCE or ProCoder.
I don't think the difference is that large.

Btw, dvd mpeg-2 is stored as YV12.

Guest
30th November 2005, 01:17
Best method for colorspace conversion You've ignored or forgotten about forum rule 12. Please re-acquaint yourself with it.

mp3dom
30th November 2005, 09:40
Ok, Thanks Wilbert for the explanation and Neuron2 for the warning :) (sorry)

mimungr
30th November 2005, 10:29
I always do the conversion in AVS since it allows you to specify the color coefficients used: BT.601 vs. BT.709. I don't know if this is possible in VDM.

Wilbert
30th November 2005, 10:55
I always do the conversion in AVS since it allows you to specify the color coefficients used: BT.601 vs. BT.709. I don't know if this is possible in VDM.
No, it isn't. VD/VDM uses BT.601.