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Copying A DVD To A CD?
Kreed wrote to us about an article on Tom's Hardware that details the process of compressing the content of DVDs down to CD length. Pretty cool compression.
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Reviewing something for the pure geek nature of it all, regardless of the wrath the RIAA will bring down ;)
:)
Yeah.. let's see them try to silence Tom
My idea is to scan a DVD into Photoshop, then resize it way the hell down and burn it onto a cd. Or even better, just photocopy the disc, cut out the circles, and glue or tape them onto some of your old AOL promo discs. Try it, it works!
Compression ratios like that make me very happy. Any guesses to what ogg video will look like? I'm anxiously awaiting ogg vorbis (audio format) myself. I hope this project catches on, because I would like to see a suite of fully-opena and free multimedia formats. Vorbis promises to be very flexible, and it would be nice if we could get the same kind of compression in MPEG-4 into a free package, and this looks like it could be the outlet for it, with the right modifications.
WARNING: there is a trojan on your
This isn't news, and it isn't something I want to hear about...
It *is* very cool, and arguably fair use, but unfortunately, if the media ever really gets wind of this, we'll see the entire stupid mp3 war over 'mp4', only ten times worse.
Ok, I suppose it's unavoidable, but if you thought all the mp3 stuff we've heard about for the past few years was stupid, well, this will be ten times stupider with the MPAA backing it.
Also, I suppose no one will mention Microsoft in this, even though everyone traffics in '.asf' files. (Just like everyone talks about Napster, even though many college students share their hard drives, and use Windows File Sharing as their mp3-pirating platform...) Of course, the entire format/medium issue is incredibly stupid; it's just a tool. But rational argument hasn't stopped these people so far...
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pb Reply or e-mail; don't vaguely moderate.
pb Reply or e-mail; don't vaguely moderate.
In a year's time, most if not all new PCs will be shipping with DVD drives. And most of those who have not upgraded will not be target customers for the pirate CDs this will presumably produce. Likewise, anyone who uses this technology for their own copying obviously already has a DVD drive.
So who would really use this?
from the FlaskMPEG home page:
The authors of FlasKMPEG have come across a program called 'FlasKMPEG DeCSS'.
We want to express very clearly that such program or any other derived from the original is no way related with the official 'FlasKMPEG' project in any way. FlasKMPEG sources are available under the GPL license and it's totally out of our responsibility the legal implications caused by the modifications or variations from other developers performed over our code. The original FlasKMPEG can't and won't read files from encrypted DVDs, and even then, copyrighted material should not be processed with FlasKMPEG.
Opus: the Swiss army knife of audio codec
Seriously...speaking of DivX encoding (or MPEG-4 or whatever you want to call it) will all you people out there stop leaving these files with the .AVI extension? Is it that hard to put use a new extension like .divx or .dvx? Are Windows users that lazy that they can't be bothered to register a new extension to Media Player? Maybe we need to get some of those DivX warez groups on IRC to change the name of the file before they release them. Just imagine the chaos that would ensue if people started releasing .WAV files encoded with using the MPEG-1, Audio Layer 3 codec instead of .MP3 versions.
= -=-=-=-=-=-=-
PS - I'm looking at you Microsoft. Quit naming a billion files ".DOC" when not single version is intercompatible.
Bleah! The one thing I miss from the Macintosh is the fact that every file had a four byte header that identified the type of file so that this whole extension mess was unnecessary.
- JoeShmoe
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
- Warning:
This is kinda like selling guns unrestricted and saying "please don't shoot anyone, cuz that would be against the law". Oh wait, you guys already do that.The author declines any responsability from the use of this program. This software can not be used with copyrighted material because doing so, would infringe many laws all around the world.
The author doesn't intend to promote piracy by any means, and the scope of the application is limited to video processing tasks with home made digital video material.
Joke, okay. Calm down and don't flame.
But seriously, I want the ability to back up my DVDs, and play them back on machines without DVD drives, in exactly the same way that I can backup audio CDs to tape, and play them in my car.
I don't see anything in the least bit illegal about FlaskMPEG, but I'm sure that the MPAA lawyers will be doing their best to take a different view on that.
I wonder whether this could have any impact on the DeCSS situation? Surely, it would be better to let people view DVDs unrestricted under Linux, rather than be a pain in our ass and encourage us to start backing our DVDs up on CD.
cheers,
G
Back when DivX;-) first appeared, I took a DVD, a handful of programs, and a lot of spare time to see what I could come up with. Here are my results:
But it's not that easy, either. If you're a CS major, you should be able to do it in three or four hours. If you're an average Joe, good luck. You'll need it. MPAA, your day is coming, but it's not here yet. (See below.)
No kidding here, guys. On a PIII 350mghz, playback was choppy. Tom here used an 800mghz Thunderbird. You probably need around that to get decent playback.
It took, on my aforementioned PIII, about seven hours to encode half an hour of Wallace and Gromit. Even with a smokin' computer, you'll probably need to let it run for a while.
It's not perfect, guys. Especially in scenes with lots of movement of colours (like an explosion), you get some fuzzies. It's about the quality difference from mp3 from cd, though, I'd say. I certainly wouldn't mind watching a movie in DivX;-) format, but it's no home theatre.
DeCSS makes it easy to rip a movie quickly, but other programs exist that are just as simple. I've heard rumours of one that brute-forces the key to the DVD--anybody know about this one? At any rate, I don't think it can be argued that DeCSS's even main purpose is for this sort of thing. It's obvious that DeCSS is used more often for some easy-listening music and t-shirt wear than for piracy.
Conclusion:
MPAA, your day is coming. But take note that it's because of DivX;-), just like the RIAA's problems are mp3 (not RealJukebox). As for DeCSS? You're barking up the wrong tree with that one. Of course, if you're worried about people disabling region codes and/or watching their DVDs on their Linux machines, DeCSS is your man.
Dlugar, bearer of the spork
Computer Go: Writing Software to Play the Ancient Game of Go
Really, we know how to do GOOD video compression, we just don't have the space/time to do it with modern computers.
I mean, if you do the following, you'll get great encoding, but it is EXPENSIVE.
step 1: drop the color space resolution in half, the eye can't see it. (this is the first step in JPEGs)
step 2: Resample the image in time to 30fps (this is ideal)
step 3: resample the image in space to a hexagonal, instead of a rectangular grid, this spreads the corner distance problem.
step 4: resample at half the luminance resolution, compress, but cycle the resampling offset in time. Persistance of vision reconstructs the proper luminance map.
step 5: search the (much reduced by this point) 3d matrix for domain/range mapings (this is the fractal step, it takes much processor power) You probably need to select smallish block sizes for this in time, or it gets much harder. Of course, the bigger the chunk you encode at a time, the better the encoding ratio.
and to view it, just reverse steps 5 and 3.
Its kind of like strong AI, its easy to say 'search for domain/range mappings', and it's easy to write code to do it. It just takes more memory and processor time than we have available to give useful results.
-- Crutcher --
#include <disclaimer.h>
-- Crutcher --
#include <disclaimer.h>
The result is that the MPAA's assertion that the DeCSS case is about piracy is gone. It was never true anyway but now any fool can see it for what it is - a smokescreen. So this actually helps the DeCSS defendants.
The language of the article above compared to the actual images within the article and observed quality are strikingly different.
I would score the difference as a 10 on the "I never had sexual relations with that woman" scale.
The difference in the propaganda and the actual images/sound has been a feature at all the levels of the compression discussion. Most of these disconnects come back to some fundamental misunderstandings about a little thing called "playback fidelity".
Playback Fidelity Recap follows:
As anyone who has ever chased "great sound" will know, half-decent stereo systems start at around $3000 with $1500 of these dollars being spent on the speakers alone. Listening to MP3s on half -decent stereo systems is a painful experience - fortunately outlawed as "cruel and unusual punishment".
But there are (at least) two other forces at work in the world of sound. Firstly, the bald fact that very very few people listen to music on half-decent stereo systems. Secondly, the bald fact that for around 20 years, the people making the music have had access to technologies known collectively (of course) as "compression". This is the process whereby, in post-production, the "raw" recorded sound is "dumbed down" or "compressed" to fit the sound qualities of most people's playback equipment. It is lossy compression - as parts of the sound are "thrown away" to concentrate on the most "noticed" parts.
This 20(odd)year process has resulted in a number of things, including the incredible "bass" that people feel that they get from ghetto blaster sized and priced playback units and (standard) car stereos. Also, people have become accustomed to the "compressed" sound and have actually come to really like it. Try playing these same tracks on half decent stereos (actually, don't) the experience is very different. Examples of extreme compression would include most rap/dance music, Britany Spears et al, etc. etc. Or really any music made for people with limited access to high quality playback.
And so at the playback fidelity that most people experience (PC speakers - $100) MP3s of course sound great. Likewise, at the playback fidelity of television tubes that are tuned for VHS in PAL or NTSC, I bet that DVD video ripped to 750MB looks fine.
Get a monitor quality TV set (you'll probably be able to afford one in a few years) - and suddenly VHS is unwatchable, free-to-air has chunks missing, cable "rips" every half minute or so, and DVD is almost acceptable, but you'll secretly hunger for something more.
I feel that playback fidelity shouldn't be forgotten when claims like "Barely noticible quality loss" are made.
besides that id like to mention that people should be way more exsited about this. people don't seem to relize that in about 2 years the MPAA is going to totally freak out because napster-forvideo will have every freaking movie and video for download.
that and your 2.5ghz computer can record a whole movie to a tiny 700megs on your 2.5 terrabyte drive.
think about it!
-Jon
oh ya, Tom didn't mention that DiVX is the actually Microsoft MPEG v4, just cracked to remove the copyright stuff. how they got hold of it, i can't tell you. also Microsoft and Real seem to have slightly better codecs now, Microsoft Video V7 (why 7? ,marketing) and Real 8, both are REALLY freaking amazing. even better then standard MPEG4, which as someone pointed out is bassicly Quicktime, which uses the sorenson codec. Not that Quicktime isn't da shit, it is.
this is my sig.
The quality is just not there.
You're right, it isn't a replacement for DVD. It wasn't meant to be. Just like MP3 isn't meant to be a replacement for CDs. It's a great way to compress the file down to be easily transferrable across the internet.
Compressing an 8GB file to 700MB will be lossy, and there's not much you can do about it. However, I'm willing to trade some picture quality for portability. I can burn several CDs with movies and watch them on the road on my DVD-less PC.
Besides, I'm spending $40 a month for this cable modem. At least I'll never have to rent another video.
No boom today. Boom tomorrow. There's always a boom tomorrow. - Cmdr. Susan Ivanova
It takes a good 10-15 hours on a fast machine, like Athlon 650, to do this.
*cough*BULLSHIT*cough*
if you add "in FlaskMPEG", then you're correct. i routinely do a whole DVD in 8-9 hours on a p3-500. granted, the CPU is spiked at 100% the whole time and i usually don't use the box for much else. but it doesn't take as long as everyone thinks if you use good software. check out the real howto.
From a motherboard manual, error beep codes: S-L-L-L-SS: Speaker Error
I've been downloading nAvi and DiVX for quite some time now and even lately have been hitting up the local Blockbuster for DVD's to rent and rip to DiVX ;-). I will say that I am suprised at how many people havent heard of the mpeg4 (divx) codec as of yet around here since the readers here at slashdot are supposed to be on top of this sort of thing, but anyway, i guess some of you guys have jobs lol. anyway, a few points...
- Tom's hardware exaggerates when they say the quality is almost unnoticable. In order to fit an entire movie onto one 700 MB CD you have to set the video bit rate at about 700kbits/sec. Even then, the DiVX codec will compensate for high motion scenes by raising the bitrate and will lower the bit rate for still scenes with only talking. However, the difference between a movie encoded at this bitrate and the DVD is still quite noticeable in scenes where there is a high amount of movement, and even in low motion scenes the background begins to look blocky since the compression algorithm somehow determines that the background data isnt as important as the foreground.
- another good thing about the DiVX codec is that you can use the new WMA 2.0 audio codecs for extremely high quality audio compression which crunches down 2 hours of audio in to approx 60 MB. the difference in the audio quality is negligible to me, but then again, i dont have a 5.1 surround system (you can only encode to WMA at stereo or mono).
- you STILL have to decrypt the movies using either DeCSS or a program similar to this. I've started to use CladDVD 1.6 over the past couple of weeks or so since it parses the VOB files as it decrypts them to check for multi-angle scenes and the sort (which can REALLY screw you up when ripping a DVD by desynching the audio and video). my method has been to decrypt using cladDVD, encode to DiVX using FlaskMPEG with PCM audio, opening the audio in sound forge and normalizing it (flaskmpeg has a bug in the latest version which causes the volume to be quite low), and then multiplexing the divx audio with the new normalized sound file with Virtual Dub (which will also compress the audio at the same time to your format of choice).
- this process takes TIME!!! an hour to decrypt the VOB's...10 hours or so for a 2 hour movie to encode in flask (my p3-550 averages about 4.71 frames per second)...an hour to normalize the audio, and another 20 minutes to create the final avi with the normalized audio track.
- everyone saying that you need an 800Mhz machine to playback DiVX is misinformed. My p3-550 plays them back just fine. i also have a friend with a k6-2 500 that is able to play them back without dropping frames.
- TV out on your video card is a MUST, unless you want to watch movies on your monitor. there's been rumors of a DiVX player for the Playstation 2 (oh, goh, i will have died and gone to heaven if that ever comes to light). until then, there are NO standalone divx players : (
here's some links for more info...
DiVX: http://divx.ctw.cc http://www.gdivx.com
FlaskMPEG: http://go.to/FlaskMPEG
VirtualDub: http://www.geocities.com/virtualdub
Divx-digest: http://www.divx-digest.net/
RACK ME!!!!
I think tkhe perfect culmination of all of this would be a MPEG4 copy of Valenti shooting an eggroll out of his arse when he finds out about this program. I'd pay quite a pretty penny to witness that, firsthand... Ten bucks says he keels over on the spot. Preferably after the eggroll, tho.
.02
My
Quux26
My
Quux26
www.crashspace.net
Has anyone actually tried to watch VHS on a monitor. I did once I got my ATi All-in-Wonder, damn was it crappy. TV is better resolution than VHS. DivX is far better than VHS, it doesn't stand up to DVD, but I think it is perfect for recording television. A 1 hour TV show usually is about 150-200 MB. Plus the encoding time isn't too bad, and it plays smoother than Quicktime with the Soreson codec. Actually the only DivX that I wasn't able to play on my K6-2 450 was the Matrix trailer from the DivX site.
And we know full well how futile it is to stand in the way of progress. History is full of people who tried to stand in the way of progress only to find out that progress is a steamroller that will squash you flat. History will not be kind to the MPAA or the RIAA. They'll probably be noted as a bunch of idiots who tried to stand in the way of progress. Hopefully they won't do too much damage before they go the way of the dodo.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Why would it be illegal to compress or change formats of copyrighted material? It is illegal to distribute copyrighted material without consent of the authors but compressing isn't illegal. Does anyone know an example where I am wrong?
Molog
So Linus, what are we doing tonight?
So Linus, what are we going to do tonight?
The same thing we do every night Tux. Try to take over the world!
recompress dvds, that is... :-)
:-) files is considerably (and very noticeably) below DVDs if you're squeezing the movie into a CDROM-sized disk. Many folks who do this scale the frame size down, which greatly improves image quality. If you don't, almost anyone would notice the extremely-obvious compression artifacts. I've found that using the "low motion" codec with bitrates of 1900-2100 kb/s works very well, and is very acceptable. You'll notice artifacts in scenes where the codec is having to make tough choices about where to spend its bits (like scrolling credits with live action behind them), but the result is otherwise *very* good. This gets you movies around 1.5GB (depends on length, etc...) that are too big for a CD, but fine for a HD.
.IFO files to rip just the files needed for the main video stream, Macrovision removal, etc...).
:-) distribution is also "illegal", in that I think it includes pirated codecs (ie, the Fraunhofer "professional" quality MP3 encoder).
I travel for work a lot, but my laptop doesn't support an internal DVD drive. So rather than lug DVD's and a clunky external drive around with me, I recompress and put them on the HD. Decompress speed is just fine on the laptop's 500MHz PIII once it gets going, but it is jerky for about 20 seconds until everything gets buffered and cached correctly. I know the MPAA disagrees with me, but I see this as fair use...
Anyway, a couple of points to add:
1. Video quality of DiVX
2. As you mention, DeCSS is not the best way to rip DVDs anymore. I much prefer "cladDVD". Other than the short delay to brute-force the encryption key (which is often almost instant) it's just as fast as DeCSS, is considerably easier to use, and has more features (like interpreting the
3. Besides DeCSS, the DiVX
4. How hard or easy doing this is depends on the movie. Fancy releases like the Matrix and T2 are hard because of all of the extra crap thrown in, especially multi-angle stuff. Subtitles are a real pain in the neck too. A few movies have poor telecining (the process of taking a 24fps movie and converting it to NTSC) that can't be removed. I won't go into the details, but the result is a crappy-looking conversion because every few frames is the interleaved result of the two two frames immediately before and after it. This is really annoying on a non-interleaved display like a computer monitor.