transcoder for mpeg4?

[olnima]

Maybe not the right forum, but one question please:
Is transcodeing (like DVDShrink, InstantCopy f.E.) possible for mpeg4-streams or is it just a mpeg 1/2 - thing because of the kind of compression?

Greetz
Olnima

[Leak]

Originally posted by olnima
Maybe not the right forum, but one question please:
Is transcodeing (like DVDShrink, InstantCopy f.E.) possible for mpeg4-streams or is it just a mpeg 1/2 - thing because of the kind of compression?

I can't think of a reason why it shouldn't be possible, but I guess since MPEG-4 usually is waaay smaller than MPEG-2 there's less need for a transcoder - after all, you're probably hard pressed to find MPEG-4 files (except perhaps files at HDTV resolution) that don't fit on a single-layer DVD...

np: Dntel - Superpitcher Kompakt Remix ((This Is) The Dream Of Evan And Chan)

[olnima]

Thanks Leak,
I ask for two reasons. First - if the kind of transcoding is technically possible with mpeg4, second - sometimes You want to put f.E. 4 movies on a DVD but together they are let's say 4.8 Gigs.
In cases like this transcoding one or all movies would make sense IMO.

Greetz
Olnima

[Didée]

After I got myself a DVD burner, there was some major swearing going on on my side -- when I actually started to realize that the ratio 4480/800 ~= 5.6 is as odd as it can only be :devil:

I really would like to reduce that huge pile of Mode2-CDs by copying them to DVD. But ~500 MB loss per DVD disc is way too much for my taste!

I *do* have plenty of "small" files to use as filler ... but that would mean to spread all those music videos over manymany disks, instead of having them all together on just a few. I particularily dislike that idea, either.

Life is a b*tch sometimes ... /*starts swearing again*/


- Didée

[Leak]

Originally posted by olnima
I ask for two reasons. First - if the kind of transcoding is technically possible with mpeg4,

Sure it is - it's not as if MPEG-4 is sooo different from MPEG-2, it's still using quantized DCT blocks, and you still can re-use the motion vectors and just quantize the DCT coefficients more. Of course, if your file contains B-frames and you want a file without or with less B-frames the transcoder can't do that (at least not without totally decompressing and recompressing those frames), but just shrinking the size of the frames via heavier quantization should be possible.

second - sometimes You want to put f.E. 4 movies on a DVD but together they are let's say 4.8 Gigs.
In cases like this transcoding one or all movies would make sense IMO.

I don't know... I'd rather use an extra DVD in that case, but obviously your mileage may vary. :)

I like DVD Shrink in case a whole movie doesn't fit on a DVD, as swapping the disc in the middle of it would be really annoying, but if we're talking about putting 3 instead of 4 movies on a DVD I can live with that - also, I really wouldn't watch 3 or 4 movies in a row without getting up in between... :D

np: T.Raumschmiere - Musick (The Great Rock'n'Roll Swindle)

[olnima]

> ... but if we're talking about putting 3 instead of 4 movies on a DVD I can live with that... <

I surely also can live with that but hundred years ago everyone could live without having washing-machines, cars and mpeg4-codecs ... ;)

I agree that transcoding a dvd is more important than mpeg4-files. But (as Didee mentioned above) it would not be useless having a good transcoder for mpeg4.
Greetz
Olnima

[unmei]

How long do i have to wait till your avatar stumbles?

[Selur]

mpeg4->mpeg4
hmm,.. thinking,.. 'hinted me' didn't work so well, but maybe if one could extract enough information out of the 'original' mpeg4 file one could lower the size be doing a reencode with another quant matrix for lowering the file size,..

Cu Selur

Ps.: personally I would welcome a gpu using mpeg4 encoder more than a mpeg4->mpeg4 transcoder.

[izx]

When this problem hits me (for a few MB more... :-) , I shrink the audio. I generally deal with AC3 sources, but your existing rips would probably be MP3. Think about re-encoding the audio of one or more files, to something like HE-AAC, for example.

Originally posted by Didée
After I got myself a DVD burner, there was some major swearing going on on my side -- when I actually started to realize that the ratio 4480/800 ~= 5.6 is as odd as it can only be :devil:

- Didée

[Didée]

No, that's not an option. Doing the math, I'd have to shrink the audio by ~55MB on average. Now, taking an ~100 kbps Vorbis stream (often encoded from mp2 [DVB cap]), and re-encoding this to the "needed" bitrate of 48~55 kbps, perhaps even to yet another coding technology ... hah, no. Not really. My ears are not bad enough for that.

[vinetu]

DVD Overburning is the best (Me Think)
Remember Old Times -the first CD-R was 650 Mb and no more!
Now on the same media you can burn up to 850 Mb (99min).

For now I did not found the way to do some with DVD media...still trying ;)

Best Regards!

[Borat Sagdiyev]

But....

A mpeg4 transcoder would be nice if speed is an issue.

So it doesn't exist?

[Teegedeck]

I really would like to reduce that huge pile of Mode2-CDs by copying them to DVD. But ~500 MB loss per DVD disc is way too much for my taste!Regard it a safety-margin - with most recorder/media combos, the quality of a write degrades dramatically to the end of a disc. :)

[bill_baroud]

when I actually started to realize that the ratio 4480/800 ~= 5.6 is as odd as it can only be :devil:

Then just buy crappy dvd media, and leave the last 500Mb alone, because you will not be able to re-read it anyway :D
That's saving you time and money, w00t :D

-->[]