Log in

View Full Version : Why DVD transcoding is dumb


oddball
27th February 2004, 01:20
Wasn't sure whether I should post this in the one click DVD backup section or not. Please move if you feel it is in the wrong place.
---

I don't see the point. So you save download and can get it on 1 disc. Big deal. I can see the point if transcoding to DiVX/XviD but if I want a DVDR of the movie I want it uncompressed. As it is supposed to be. Id rather download the few extra gigs and put it on 2 discs if needs be.

DVDR releases that transcode are worse than DiVX/XviD in the sense that you are spending all that extra download time and DVDR space on something that is subpar to the original.

I look at it this way. It's like some record company releasing a CD that is manufactured at the factory to fit 90 minutes of audio on it and then someone making a rip of it only shaving off enough data through "lossy" compression making it small enough so someone can fit that onto 1x 80 minute CD-R instead of 2x 80 minutes CD-R's uncompressed.

I don't care if the difference can be impercievable to the eye. That's not the point.

Or as another example. Someone zipping/rar'ing a bunch of MP3 files at full compression saving hardly anything in the process (Which also results in longer extraction/decompression times. I hate that).

DiVX/XviD compression makes sense from a bandwidth saving perspective (As does MP3 since you can get more on your portable digital player etc) but DVDR transcoding is just plain dumb.

Of course this is not just based on transferring data over the net (Which some may call copyright infringement anyhow).

But even if you are transcoding for home use you are fooling youself. Sure you save the original disc from being scratched. But unless it's for backups for children because you don't want them scratching the originals then you are losing out on the full quality of viewing the original (Just because you could not be bothered to do a proper 2 disc backup and compressed it to 1 disc in order to save 1 disc and not have to get up half way through the viewing).

Oh well. I guess it's up to you if that's what you want to do. Perhaps this won't be such an issue once dual layer burners are out there.

Just my opinion.

Gaia
27th February 2004, 01:37
I don't understand what you are trying to say... But if i understand right you're talking about piracy?

All real DVDR releases(released by some release group) are encoded with CCE not transcoded.

I just backed up Asian movie with DVD Shrink. Compression ratio was 96%. You're are saying it was stupid and i should have splitted it to 2 DVD's?

To me it looks like you just bought DVD burner...

You don't have to transcode you can encode it with CCE to smaller size.

JustinH
27th February 2004, 03:14
I back my dvd's up to watch them in the truck, when my passengers are watching movies in the truck, they don't care about perfect video quality.

Its nice because my dvd's can sit in the changer at home, and I don't have to worry about one of my buddies scratching them up in the truck or whatever.

DVD Shrink is a good program, I find myself cutting all the menus out of the dvd's and everything except the movie. When you cut out all the filler its so much easier to manage, pop it in and it autoplays.

JH

r6d2
27th February 2004, 03:30
Originally posted by oddball
I don't care if the difference can be impercievable to the eye. That's not the point.I understand that somehow you think DVDs are losslessy compressed, and that DivX/XviD are lossless too. :confused:

Well, just in case, in fact they are not. If the source was uncompressed a 2 hour movie would require about 100-GB, which would not fit on any consumer removable media.

Anyway, that download thing you are talking about is either another clear misunderstanding of the scope of this forum or you really think you'll be able to download a 100-GB file in real time.

oddball
27th February 2004, 06:01
You really did not understand my post at all did you? I am saying that transcoding (Re-encoding the MPEG2 stream) to make it fit onto a single DVDR is not a great idea. Recompression is fine for DiVX/XviD because it's the equivalent of MP3's It allows the transfer of movies at a reasonable quality onto smaller media (CD-R's) or via the internet for low to mid bandwidth users.

DVDR's on the other hand are big in themselves and do not lend themselves to low to mid bandwidth users but high bandwidth users. If you are going to transfer DVD images then recompressing them by only a small amount makes no sense to me. If I want a DVD image I wasn an NON-RECOMPRESSED image with all the extras stripped out. If it still does not fit on 1 DVDR so be it. Just split it. All these people talking about 30% recompression with DVD Shrink and CCE etc well...it may be fine for taking out to your car or loaning to a friend or for the kids but for anything else I'd rather it be the exact same untouched MPEG2 VOB's that were on the original DVD thanks (Minus extraneous crap and protections of course).

Of course thinking on what I have written it mainly refers to stuff I really should not be talking about on this forum so I will leave it at that and if the mods want to lock this thread or delete it I will leave it to them. I was just ranting :)

Doom9
27th February 2004, 08:25
just from a theoretical standpoint, downloading 4.3 or 8.5 GB, there's a definite difference in time. And your comparison to MP3 is flawed. Audio CDs are lossless. To be able to compare DivX to audio CDs, you'd have to use an uncompressed 100+GB video as the source (and uncompressed 6 ch PCM sound).

On a more practical note, you are talking about things we don't talk about here.