Advice for Multimedia Project

[slinga]

Hey guys,

I'm working on a stupid school project to compare the quality of various video codecs. The plan is simple enough, take a dvd, rip it, and encode it with various encoders (Xvid, DivX 3.11, DivX5, Real, QuickTime, etc) and have people say which format is the best quality. Any advice on how to actually do this? I've ripped the DVD with DVD Decryptor and I know have a bunch of .vob files. How do I convert that to anything useful? Can I run an encoder directly on a .vob? Any advice is appreciated.

 

[mal]

Have a look around Videohelp.com.

 

[lordofduct]

wow, that test is a very poor assesment of video quality....

It can all depend on what software you use to do the encoding, the process one follows to do it, all sorts of stuff.

Id start by converting that into its mpeg2 and sound files. Using tmpgenc you can do that with the mpeg tools. The sound file comes out as an ac3 so you'd have to use some tool to turn it into a useable format like wav.

There is a lot of all in one software out there like DVD2AVI, simpledivx or highend software which will cost you money. They generally cause poorer quality (DVD2AVI just blows in my opinion) unless you use the highend software so you are going to want to split the vobs all on your own. Also the low end software usually is specific to one codec, causing you to have to DL and use all sorts of different processes.

videohelp.com is a great resource for all kinds of tools though. Have fun doing it and hope you have a fast computer (with a pentium preferably, my 2 Ghz P4 will encode faster then my roommates AMD clocked at I think 2.8... we both have the same amount of RAM, of course other things play a role, but I seriousily find the P4 much faster at it.) You will be spending several hours per encoding process for each codec format.

 

[Scared0o0Rabbit]

I would imagine hard drive speed is a huge bottleneck also...

 

[morlock]

It is mostly processor dependent. Go to Doom9.net. They have freeware tools and tutorials on how to do it right. One thing, if you are in the US violating the DMCA might not be a good basis for a school project.

 

[Scared0o0Rabbit]

I've done enough video encoding to know that hard drive speed is a bottleneck, especially once you start building systems like the one I have. Hard drive speed tends to be a bigger issue when working with large files and sets of files as compared to your typical 90MB episode of whatever, as it's trivial to write 90mb to a hard drive. However, writing 4GB to a hard drive can be rather time consuming, especially if the hard drive is fragmented. It probably also helps to have the source drive and destination drive on seperate IDE channels.

 

[RitualOfTheTrout]

No, your biggest bottle neck will be the processing of the video file. The hardrive wouldnt become a speed bottle neck until you could encode a video file at like 1000s of frames per second. Of course all of this is dependant on codec/software/quality settings.

Now transfering a 4gig file will take a little time, but not nearly the amount of time it will take encode one.

 

[Scared0o0Rabbit]

That may be true, but if you're attempting to read and write to the same hard drive at the same time let alone the same ide channel while doing video encoding, you are going to notice a speed hit.