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Video Shrinks With MP4
molda writes: "The The BBC is reporting that the New MP4 format is now appearing on websites. The compression routine utilised by MP4 is cable of converting an hours worth of video to a 350mb file. " Until there are cross platform players and encoders I don't see it making each inroads, and there still are some compression issues (but then again, a 128kb/s MP3 wacks out music's treble and bass pretty badly too and that hasn't slowed down its acceptance).
Ok, saying "MP3 wacks out music's treble and bass" is pretty inaccurate.
The overall frequency response of MP3 is essentially flat. If you do the standard audio tests of sine waves at various frequencies, you'll get basically perfect fidelity. That's because sine tones are not very complex and thus compress very well.
MP3, like all lossy compression schemes, removes information complexity from the signal, so that it fits into a much smaller bitrate channel. The function of the magical "psycho-acoustic model" is to separate out the complexity that you can hear easily (for example, the attack on a snare drum) from complexity that you can't (ie small signals at frequencies that are close to frequency peaks, so are masked out). At any given bitrate, MP3 encodes as much as possible of the former signal and ditches the rest. The higher the bitrate, the more gets encoded.
Now, that said, at 128kbps, the better quality MP3 encoders suppress frequencies higher than 16kHz. The reasoning for this is very sound: most people (myself included) can't hear these frequencies at all. Nonetheless, because they're up there in the frequency spectrum, they can encode quite a bit of informational complexity - in fact, the 16kHz to 22.05 kHz band has almost exactly enough bandwidth to encode two telephone conversations. By ditching this band, the MP3 encoder gets rid of a lot of informational complexity that generally can't be heard anyway, leaving more for the actual music.
If you insist that you can hear near-ultrasonics, then simply encode at 160kbps, or use a better encoding format than MP3, such as Vorbis.
Speaking of which, my understanding is that MPEG-4 is absolutely riddled with patent problems. I'm surprised this wasn't mentioned in the article. If you rush to adopt MPEG-4, you've given up the right to whine about big evil corps and their patents - it's you who's adopted patented technology. Support a free video codec instead.
LILO boot: linux init=/usr/bin/emacs
Whats this about MP3 ruining high and low end? At 128kbs the psychoacoustic alogrithms should just remove 'redunant' sounds that people don't hear anyways. Sounds like someone is judging MP3 quality through 1-inch PC speakers.
Boy, that BBC article is riddled with errors. The format is known as MPEG-4, not MP4. If you recall, MP3 is actually MPEG-1 Layer III audio encoding. MPEG-2 is a video and audio encoding format (as used on DVDs). MPEG-3 was never released. MPEG-4 is the successor video and audio compression format to MPEG II, not the successor to MP3.
DivX is not, as reported "the name of a failed technology that tried to create limited-life video cassettes", it was an attempt to create time-limit DVD discs, that's an important distinction.
The MPEG-4 standard is based on the QuickTime file format. It was only formalized in March of 2000, more than six months after the Microsoft "codec" was released. So the Microsoft "MP4" codec is an incomplete implementation of an earlier draft spec of the format and is not compatible with real MPEG-4 bitstreams. See this link for the real scoop on MPEG-4.
Sailing over the event horizon
Actually, it's MPEG-1, Audio Layer 3, but I imagine you knew that..
please correct/update this where I am wrong.
Mp3 = file extension and popular name given to audio encoded with MPEG1 layer 3.
MPEG1=Standard for compressing Video and Audio
MPEG2=Standard for compressing Video and Audio
MPEG4 version1=Standard for compressing Video and Audio
MPEG4 version2=Enhanced version of MPEG4, backwards compatible with MPEG4 version1
Microsoft MPEG4=Typical Microsoft (incompatible) implementation of open standard. Hacked together from unfinished draft of MPEG4 (version 1?)
DivX(consumer product)=Defunct comsumer Digital Video format (like DVD, except no one bought it)
Div-X(codec)=Hacked version of Microsoft's hacked version of MPEG4
"MP4" (as used in this article)=Div-X codec (see above)
Hope this is usefull (and accurate)
One of the Mpeg-4 hacks is called Div-X.
. html
It's widely used in the pirate scene, and apparently works very VERY well for compressing 2 hours of video/audio into about 650 MB worth (1 cd). The only issue is in order to play these types of files you need a fast CPU, about P2/300.
Although this use is not legal, it shows that Mpeg-4 is here and should quickly replace the current defacto standard.
http://www.digital-digest.com/dvd/support/mpeg4
Above is one site , explaining lots about MPEG-4 including the various formats MPEG-4 can be applied to (avi, divx, etc), as well as platform-related information.
Another Div-x related site at:
http://www.mydivx.com/
It seems this page is requesting help to make a Linux div-x port, but there seems to be little and/or no substance.
http://linux.divx.st
Here's a link to an Open-source Div-x contest, albeit for the Mac, but it's here:
http://www.flashingyellow.com/contest.html
Where are the specs on the MP4 format? By encoding, do they mean from MPEG2 -> MP4? The "hacked" codec from M$, does anyone have it out there (source?)??
"MP4" is really called MPEG-4 Version 2. The full spec. can be found here.
MPEG-4 defines how to compress and decompress raw video into the MPEG-4 bitstream format. "Encoding" refers to the compress half of this process. If you are converting from one compression form (e.g. MPEG-2) to another (e.g. MPEG-4) you are "transcoding".
The Microsoft codec, whether hacked or not, is based on an early draft of the MPEG-4 format and is incompatible with real MPEG-4 bitstreams.
Sailing over the event horizon
If I'm not mistaken, Microsoft's ASF format has been using MPEG4 for a while now.
With ASF, you can easily fit a movie onto a CD. This works great with really BRIGHT footage, but for dark titles, like The Matrix and the 6th Sense, it pretty much sucks the nut. The darks all blend together, and become quite.. uh.. MPEGgy. Weird artifactish type things start showing up, and the video gets pretty chunky.
It's like losing low tones on music. The darks become all chunky, vague, and distorted.
Then again, what do you expect, for a movie that fits on a CD?
Geez... DivX has been around for ages!! And it was created from the SOURCE CODE of Microsoft's own MPEG-4 encoder. These two "formats" are interchangable; one is a hack that has seen improvements, the other is Microsoft's own "branch" of the original codec.
As for playability, I can compress an entire 2 hour DVD into around 600MB with a 96kbps MP3 soundtrack, maintaining original letterbox (720x288) resolution.
While CommanderTaco's been sleeping, several companies have already announced set-top players for MPEG-4, and there's even a version of the codec (and player) available for the Mac.
OLD NEWS!
Part of EFF's strategy was to prove to the judge that no piracy using DeCSS was occuring. The rise of "DivX" and sites explaining in gory detail how to pirate DVDs with it and DeCSS completely derails that.
Just think, we're going to lose all "fair use" rights in the US so some warez kiddiez can avoid paying $7 for a movie (or $17 for the DVD). Gives ya a warm fuzzy feeling, no?
MSK
No, no, no....
.asf. It's my understanding, though I could be wrong, that it's just a patch to the MS binaries, so no source code available.
.asf files.)
There is no relationship between DIVX, the lame pay-per-view DVD scheme, and DivX, the video codec.
DivX, the codec, is simply a version of Microsoft's MPEG4 codec which has been hacked to allow it to be used for file types other than
(btw, look about half-way down this page to see what Microsoft has to say about other folks writing software that reads
Actaully, MP4 is a work in progress, M$ decided to jump the gun and release their own MP4 codec before the standard is finalised. Then the DivX team hacked the codec to make it faster. All of this seems to be lost on the BBC, whom i had a damn good laugh at when i read the article....
Syllable : It's an Operating System
While MP3 probably shouldn't have been named such, let's not exacerbate the mistake by making another one.
I'm guessing that MP3 probably gained its name not so much because the standard was MPEG-I, layer 3 (or something like that) but because that's just the file extension. Even with FAT32 and NTFS supporting long filenames (knock on wood) Microsoft still pushes for 8.3 filenames, or 3-character extensions to say the least. To top it off, people like having easy-to-pronounce and -remember three-character abbreviations. (Why was the PlayStation abbreviated to PSX, instead of just PS?)
So you can keep calling it MPEG-4, but to most people it'll be MP4. And for some reason it'll show up in the Windows property sheet as "Windows Media File."
For more information, click here.
It is the name of the freeware mp4 player (no sources, so not for linux). Get it here:
/.'d as fast ;)
http://divx.forpresident.nl/
http://divx.ctw.cc/
I didn't make them links, so they wouldn't get
Have fun. -toppk
From the article, it would appear the Microsoft has the lid on on the codec through their Media Player. Anyone know of people working on an open source version of this codec?
And how will this affect the DeCSS trial? Now the lawyers can prove that pirating is possible thanks to DeCSS putting the file on the hard drive, then compressing it. Comments? It shouldn't hurt that much (since the old "copying a video tape is fair use because the quality isn't as good" arguement would tie in here, but I'm not so sure.)
John "Dark Paladin" Hummel
We don't just like games, we love them!
52 Weeks, 52 Religions with John Hummel
On a more technical note, assuming you decrypted a DVD and re-encoded it with the new format, how much shrinkage would occur? Could you burn a DVD onto a CD? Or, more possibly, onto several CDs?
Now that I think about it, this could aid the fight against the MPAA. What if I want to buy a DVD, but don't have a player? Could I get a friend to copy my brand-new, legal DVD onto several CDs for me, so I could watch them at home? Copying for portability or backups is legal, remember...
TO BUY A NEW CAR WOULD MAKE YOU SEXUALLY ATTRACTIVE.
The author is a victim of M$ FUDding the issues. This is not MPEG-4, as has been pointed out already. What hasn't been pointed out is Microsoft "leaked" this codec to the Moviez and Pr0n kiddiez to establish momentum, as Microsoft's incomplete and Windows-biased implementation of MPEG-4 was rejected by the standards committee. Not only were current MS video implementations inferior to Apple QuickTime (even on Win32), but QT is *the* standard in professional video editing (even on Win32).
;)
Why leak an obsolete codec? Because it, and the FREE MS compression tools (what the FTC sometimes calls product dumping by a monopoly) have conditioned the video pirates into using this format for trading.
Heh... wait till they try switching their OS over to Linux, won't they feel stupid. Oh wait, never mind. Where's the |33t sense of danger in using an OS that can never be pirated?
350 Mb is a little much to download, though, even with DSL. But with 40 Gig hard drives selling for $259 at CostCO, some of those MPAA fears about copyright infringement may not be so far-fetched.
The cake is a pie
An average film can be burnt onto a CDR as that compression rate, and I think that the lower quality the image, the better the film. I know that Star Wars in MPEG format (with the wandering V) was much more enjoyable to watch than Star Wars at the cinema. South Park in Real Player was better than South Park on TV.
Better quality in these days of ultra-crisp films etc can detract from the film in my opinion. I like watching poor quality blurred, fuzzy illegal copies of films sometimes. If MP4 is better than MPEG1 in terms of quality, even if it is more compressed (they have had 8 years to improve their algorithms!) then I think it will gain a market.
But 600Mb to download an ISO image of the latest films... on a 1Mbit DSL connection say, that would take 4800seconds minimum, which is 80 minutes, just over an hour - you can watch it whilst downloading it as well! Not surprising actually, as it was developed for DSL TV applications.
Now on a modem getting 50kbit a second! 25hours, I don't see many people living with that, they will pay the £5.00 to see it at the cinema.
This will let them put so much more video footage in poor computer games though. Excellent. Wing Commander 10 anybody, with 30 hours of video footage and 1 hour of gameplay?
MP4 at hand!
Salvation! ev'ry South Park
On one shiny disc
Please, please, PLEASE let's not start calling this MP4. As many of you know MP3 isn't MPEG-3. It's MPEG-2, Audio Layer 3, shortened to MP3.
While MP3 probably shouldn't have been named such, let's not exacerbate the mistake by making another one. MPx should relate specifically to the audio compression specification, while MPEG-x should continue to relate to the entire audio/video specification.
Hopefully, when MPEG-4's audio specification catches on in audiophile circles, MP4 will be used specifically to mean audio files adhering to the MPEG-4 Audio Layer specs.
Kevin Fox
Kevin Fox