PDA

View Full Version : Perceptual Lossless DVD Transcodes


Supacon
8th October 2006, 21:18
I'm afraid that I'm rather unknowledgeable about video encoding, only understanding some of the basics, so please excuse my noob question.

I have a lot of music videos, and I've been ripping them from DVDs but the size is too much. I want to retain the highest level of quality possible, and DivX/MPEG-4 or not, I want to encode them in a way that reduces the size (perhaps to half or a third of the size) but has virtually no visible quality loss.

What would be the best way to acheive this?

I had been encoding a lot of my video into DivX but I don't really like how it seems to force me to change the resolution (i.e. my NTSC videos at 720 x 480 are resized to 640 x 480). And of course, there's some quality loss. I'm just not sure if there's a better way for me to do it. I'm not cropping anything of the borders off, and I have been encoding the audio (LPCM, generally) to ABR MP3, which I consider an inferior codec by today's standards, but it seems the best option that I'm allowed.

I think that music videos tend to be hard to compress because compared to a movie, there are way more scene changes, flashy effects, moving thinngs, etc, so this may be much more difficult to achieve than I would like.

Any advice or references to other threads would be much appreciated.
Thanks!

Your_Idol
9th October 2006, 14:13
For a beginner use divx. You can use the programs VirtualDubMod or DrDivX, the dr is easier. In both cases you can leave the resolution as is and use a setting called quality based one pass, with a quantizer of 3 or 4. This will bring the file size down and there will be loss of quality if you want to compress the video but you probably won’t notice.

Your videos are probably interlaced so I would suggest you use VirtualDubMod for its ability to deinterlace by discarding a field. I do not suggest leaving the file interlaced for compatibility reasons.

You will also need DVDDecypter to copy the dvds to your hard drive.

If you get stuck just ask here.

Your_Idol
9th October 2006, 14:16
You should crop the borders to save file space and to increase quality. (and so you don’t look like a noob)

The video may be animorphic and need to be resized. Open the file in virtualdubmod and see if it looks stretched one way or another.

Supacon
9th October 2006, 19:44
I figured that cropping borders would help increase quality, but I don't want to change the aspect ratio, because I need to play them back in a program that forces videos to 4:3, so it'll distort them if they are in 16:9 or the like... (Virtual DJ)

Maybe someday the authors of VirtualDJ will improve aspect ratio handling, so I don't have to be so worried about it.