Divx & Mpeg4 noobie questions...

[Alacard]

I've been reading up on alot of Mpeg4 and Divx 6 threads, and I'd like to convert a few movies. My main question is... what is the advantage of converting to Mpeg4 (divx 6)? Is the quality better than DVD? Or are people doing it to be able to do things like have all their movies stored on a hard drive on their home theatre PC's? Just generally curious on the reasons some of you convert from dvd to mpeg4, and how you go about it.

BTW, do any of you convert to mpeg4 and then use dvd's to store multiple movies, etc..? Have any of you archived your whole DVD collection to mpeg4?

[jon.schaffer]

what is the advantage of converting to Mpeg4 (divx 6)? Is the quality better than DVD?
No, it's impossible. You cannot improve the quality. The codecs (such as DivX) cannot invent details on a picture.
But, one can prefer the picture looking after a conversion, because one can use filter to modify this picture (e.g. denoising, sharpening, bluring, de-interlacing, etc.)

Or are people doing it to be able to do things like have all their movies stored on a hard drive on their home theatre PC's?
It's (was?) without any doubt one of the main reason...
But the pleasure of converting without dropping the quality too much is a challenge that must lead some ones to convert...

I usually make 2 CDs backups for movies (encoded with XviD + Vorbis). All my DVDs are converted (or being converted... I'm late these times :rolleyes: )

edit: typos

[CWR03]

I archive everything DVD to MPEG-4 (specifically XviD, as it's better quality than DivX) for a few reasons: I can get three or more movies onto a DVD-ROM at extremely good quality, and I don't care so much about the menus or extras, plus friends like to borrow from my collection - I only loan out the backups now. It's not possible to get a "better than DVD" conversion from a DVD source, as the source cannot be improved, but I've seen stuff made from HD-broadcast that by far rivaled DVD and was still a manageable file size.

If you're interested in creating your own, the full Gordian Knot is the way to go if you want quality. It's a lot to learn, but it's well worth it.

[xDrJx]

The main advantage is the size. DVD's are stored in MPEG-2 which is quite space consuming. When I'm doing a movie night with my girlfriend I'd hate it to pack in 8 DVD cases or so. My MPEG-4 backups allow me to store 4 movies with multiple audio and subtitles on a single DVDR, which is quite handy. And there's also my Brother, who didn't treat my DVD's with the respect they deserve ;)

[Alacard]

I tried out the Divx Converter last night with an anime DVD. Does divx support dolby digital? Or does it convert everything to stereo?

Probably for another thread, but a number of things went wrong. I chose 700mb as the target size and it ended up being over 1 gig. Also the sound isn't in sync with the video. Overall the picture quality is quite nice. I know I asked if mpeg4 was better than dvd (mpeg2), but what I really meant to ask is will there be any loss of quality when going from dvd to divx?

[jon.schaffer]

will there be any loss of quality when going from dvd to divx?
Yes, definitively. DivX (like other MPEG4 codecs) is a lossy codec. That means it is based on a loss of details to compress the video data. There will be more or less loss depending on the compression that will be applied.

Does divx support dolby digital?
I know that we often talk about DivX to point out a movie file, but this question mustn't be asked this way. DivX is a video codec. It has nothing to do with sound. The Dolby Digital soundtrack can be used with a DivX video track without any problem but all depends on the container you use.
I guess DivX Converter use the "DivX" container (a .divx file is created... ?) [and this is confusing: the container use the same name as the codec - they're smart at DivX Network] and it should support Dolby Digital. But I don't know anything about this software. (ditto for the error in filesize... sorry).

[niann]

What anime did you attempt? If it was a bad Telecine or you forgot to check the IVTC in AVS correct frame count box in the encoder options, that could cause the huge filesize and the skew in audio sync. Generally if you encode properly you can get very nice looking results from a Divx (or XviD) encode. The loss people refer to using this codec is in the actual video data. You lose a portion of the original video data, while mainting the visual quality of the source. Anime in general can be compressed well, you should see some good results. A lot of older anime source is Telecined, so make sure you understand how the IVTC process works in GKnot. If you have further problems let us know.

Cheers!

When you talk about adding a Dolby Digital sound track I am going to assume you mean with 5.1 sound. Yes you can do this, but you must remember you will need a 5.1 sound device on the PC you wish to watch the moive on.