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View Full Version : VHS to DIVX - File sizes and Quality Issues




dbainbri
23 Mar 2003, 05:27 PM
Hi all,
I've tried to find some info on this in the forum but nothing answers my question directly.

I, like many, want to convert my VHS library to a digital format. I was going to go to VCD (I have a realtime MPG cap card). My main aim is not so much to go to a removable media (eg VCD, DVD) rather, I'd be happy to just play straight from the PCs HDD (I have a MPG decoder card and therefore can view on a TV).

If I go to Divx I can theoretically save much space over MPG1 or 2 (I'll have to get a hardware Divx decoder card but I have one in my sights already...).

I have done some compression tests and I have some questions:

1. The programs I am wanting to convert are basically half hour long. In MPG1 format that is about 250Mb. Divx seems to claim a ~90% compression of DVD (eg compress a MPG2 DVD down to a 10th ot 11th of the original size - correct me if I am wrong here...) So I should be able to get my MPG1 down to 25Mb??? unless there is a minimum size. Using a 1pass encode I got a 250Mb MPG1 down to about 110Mb (at 600kps) but Of course I want to go lower... The quality is acceptable at this rate but I can't see how a DVD movie compressed to 10% can look any good based on my results.
I have just found out how to properly do the multipass so I'll try that later tonight...

2. I also realise now that it is better to do the divx compression on an uncompressed video file - which is going to be any option for me in a few days when I get a new 2.4G PC and MiniDV camcorder which will act as an analogue to DV convertor - then I can use VDub to do DV to Divx. Still... what should I be expecting? - can I get 30minutes of video into 25 - 30Mb which Divx (assuming use of DV format say)?

I'd appreciate any assistance anyone can provide. I have over 1000hours of video that I'd love to archive in divx format if it's small enough..

Thanks
Dave









I am thnking of going to a Divx Decoder card to view Divx

UncasMS
23 Mar 2003, 10:03 PM
compressing some 6000/7000mb of vob files on a dvd down to 700mb is possible and works with divx.

you cannot, however, compare an 250mb mpeg1 file to the source material VOB!

your mpeg1 is a compressed format already.

60-120 MINUTES could be (heavily depends on the source) compressed down on one cd - i.e. 700mb - but dont expect a ratio of 1minute=1mb to provide you with any decent quality!

1minute=5-10mb will be more realistic if you ever plan to enjoy those films!