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Video Shrinks With MP4 254

Posted by CmdrTaco from the little-yellow-better dept.
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).
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Video Shrinks with MP4 More

Video Shrinks with MP4

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  • DAT is either 44.1 or 48kHz sampling - peak frequency is ~24kHz... not the sampling rate.

    Most CD players apply a fairly high order filter ~20kHz anyway, to block out noise, prevent aliasing, etc...
  • Look, I love open source as much as the next guy, but the fact is that Windows still runs on 90% of the world's desktops. So would that make this kinda like DVD, which is officially limited to Windows. Hell, that never caught on, it's a dead technology. How about .asf format? That's out the door. Come on, you can be a zealot all you want, just make some sense with it.
  • But what about me - I'm a digital audiophile - I demand at least 24/96!

    [/OT]
  • Yeah right no cross-platform support is going to slow it down much. Most college-age people, who would use this the most (like MP3), are either running windows systems or linux/windows dual boot.
  • "MP3 Layer4" ? You're an idiot.

  • MPEG 1 or 2, or maybe even 1.5 depending on the encoder you're using, but who gives a fuck?

    In any case, "MP4" is incorrect, but will be used anyway because, remember, half the human race have below-average intelligence. (George Carlin said that, no?)

  • But a version that can turn massive movie files into a handier size has escaped on to the internet thanks to Microsoft.

    It developed the software to compress and decompress video, called a codec, to help the Windows Media Player program handle moving pictures sent over the internet.

    I'd like to see the MPAA sue Microsoft for developing code that could potentially make it possible for someone to pirate DVDs. That's what they're suing the DeCSS people for, afterall. I wonder whose laywers will run out of money first....

    --GrouchoMarx

  • What you are doing is cool nonetheless, but Mpeg-1 is not the best format.. there's a lot of quality loss

    Well, yeah, there's quality loss. But consider my source material (VHS EP mode). The CD's I'm creating may not be DVD quality, but they are acceptable quality and definitely watchable.

    I can easily see DVD players that may allow to play Mpeg-4 formats, amongst other things..

    So can I, but they're not here yet. One of my goals for this project was to turn out discs that were playable on _current_ technology. When better solutions appear, maybe I'll start over. Although, the discs I'm creating are very similar in quality to the VHS tapes that I'm pulling the video from.

    Of course, right now, mpeg1 (vcd) is one of the only standards. (not all dvd players support it)

    Not all, but nearly all. The big problem with homemade VCD is that while most DVD players support the VCD format, only a select few are capable of reading CDR or CDRW media.
  • Many websites are now offering MP4 versions of popular movies such as The Wizard of Oz, Saving Private Ryan and The Matrix.

    The Wizard of Oz? It's ironic that under any sane copyright system, this film would have passed into the public domain long ago. Indeed I expect that in many countries, this is the case.

    A Project Gutenberg equivalent (names please?) for old movies and TV programmes might be useful.

  • What the hell? What happened to Mpeg-3 than!
    Ahhhhhhhhhhhh!!!!!!!

  • (Why was the PlayStation abbreviated to PSX, instead of just PS?)

    Because maybe Abode would get a little pissed at it?


    --
    Marcelo Vanzin

  • Cross Platform? (Score:1)

    by Anonymous Coward
    Yeah, and Microsoft Office won't gain acceptance until it's cross-platform either.

    AC
  • 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."

    Actually I think most people will call it "Divx ;)" (which have AVI extensions for some reason). But seriously. Why would you call it MP4? It isn't an "MP4", its an MPEG-4. No one calls MPEG-2 movies MP2s. MP2 is something completly different :) It's easier to remember cuz it has three letters? MPEG-4 and MP4 have the same number of sylabils, so I really don't see how that will work. That's a really silly argument.

  • DivX installs itself as a standard windows video codec. That means any mpeg conpression software (Xing, panasonic, etc) will give you the option to encode in divX.

  • MP3 compression (Score:3)

    by raph ( 3148 ) on Friday June 02, 2000 @09:13AM (#1029650) Homepage
    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 [xiph.org].

    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.

  • Adobe, I mean... (fingers faster than brain.)


    --
    Marcelo Vanzin
  • basiccaly, you can get a something like 4.7Gb DVD recompressed in MP4 in 650Mb so you can burn it on a CD, which is great!
    --
    BeDevId 15453 - Download BeOS R5 Lite [be.com] free!
  • Actually, real headphones (read - didn't come with your $50 discman) have far *better* bass and treble extension than speakers. Lower levels = less breakup. The proximity to the ear makes this possible.

    Check out some Grado (SR-60), Sennheiser, or heck, even some nice Denons, and you'll be very surprised. Sony studio sets are decent, too (not the huge ass $10 ones at the Wiz that are the same driver in a plastic milk carton).

    You can hear far more with headphones. No room ineraction. Big difference. More clarity.
  • Where can I find info on burning VCDs to play on my DVD player? I'd love to do that!
  • Yeah, the 16kHz cut is _very_ crisp, especially when you don't turn off the filters.

    LAME, for instance, has a whole bunch of filter options, among which -k probably is the most important for such a test (it turns off all filtering).

    IMHO, those tests don't consider _anything_ beyond raw bit rate. Has nobody heard about variable bit rates?

    Personally, I can't hear above 16kHz any more, so that's not a problem... :-(

    In fact, I routinely encode my MP3s with LAME's VBR at what ends up being roughly 140 bps overall. I haven't found any encoding scheme out there that sounds better (for me).

    Another factor might be the different psychoacoustic model used by LAME (which is used to figure out which sound components can be safely thrown away). I'm not qualified to say it's better than the others, but it seems to fit what I _hear_ better.

  • Any chance this was leaked so that evidence could be produced in court that DeCSS was responsible for breach of copyright? (A couple of copies of The Matrix downloaded off the web should do the job.)

    GoodPint

  • Look on freshmeat.net, there are a lot of good mpeg players for Linux. The one I like best is called mtv. Unfortunately the license is shareware, but it sure beats xanim!

    It plays at 29 fps on a measly P133, not bad...

  • Impressive - thanks for clearing that up for me. :)
  • uuh there is no such thing as mp3 layer 4
    there is mpeg-1 layer III aka mp3

  • Do we have a chance, for a change, of having free (as in speech) MP(EG)?4 players at some point, or are we going to learn that the format is covered by n different patents, that it's specs are semi-secret and that sort of things?

    Whatever the case, I imagine there will be much pressure to suppress this format if it can fit a whole movie on a single CD-R without too much loss. The film industry is going to be scaaared to death, and we know too well the nasty things it does when it it scaaared to death.

  • Only 24/96?

    The next high-end version of Cubase will support 32-bit audio...Pro Tools as well, I think. I've already seen some softsynths that'll do that as well. Digital signal clipping begone!


    ----

  • MP3 low and high end? (Score:3)

    by gad_zuki! ( 70830 ) on Friday June 02, 2000 @08:14AM (#1029662)
    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.
  • It's both -- MS's nonstandard MPEG-4 stream inside an AVI container. The actual official MPEG4 file container format is QuickTime, IIRC.
  • This isn't actually MPEG4, but MS/MPEG4, which is a MPEG2 bloat MS tryed to push when MPEG4 was in call for papers. The MPEG board said "tkx for playing now sod off.". I doubt this thing is even bitstream compatible with real MPEG4.

    MPEG4/Audio is similar to MPEG2/Audio AAC.
  • MPEG4 Has structured audio! This means that eventaully we will be able to have most any content within one file, with a GIGANTIC header. Instrument definitions and loops, so bands can mix music directly into mp4 from the studio, and you can remix it at home (kinda like DVD with the track info, eh?). This will create incredibly small files, but the compatibility would be strange as far as studios using it. e.g. A band fitting a guitar loop through the end of a song, with a predefined volume map... aww yeah!

    Maybe eventually we can have a file format with a codec built into it, that could be compiled on a virtual machine.

    (midi on my cd player =)

  • I wasn't fooled.. the id gave it away. Plus it was pretty unbelievable that taco would get rid of one of the features that makes slashdot what it is.

    It was scary how many people fell for it, and even more scary how many said they would go for it. True maybe some were just brownnosing or karma whoring, but still scary.

  • The usually reliable BBC... (Score:4)

    by gwernol ( 167574 ) on Friday June 02, 2000 @08:14AM (#1029667)

    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 [cselt.it] for the real scoop on MPEG-4.

  • 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).

    In general people will choose convenience over quality to a certain threshold. The main problem here is that an hours worth of MP4 video (350 megs) is not something many people would want to attempt on a slow net connection - I imagine this would then be most usefull for distribution of small clips, or large clips on CD/DVD.
    -

  • Re:MPEG-4, not MP4 (Score:4)

    by Wrench ( 4256 ) on Friday June 02, 2000 @08:15AM (#1029671) Homepage
    As many of you know MP3 isn't MPEG-3. It's MPEG-2, Audio Layer 3, shortened to MP3.

    Actually, it's MPEG-1, Audio Layer 3, but I imagine you knew that..

  • First digit is five
    Second digit is seven
    Third digit is five

    numb
  • You are correct that MP3 only removes the "inaudible" frequencies from the data. However, this data is not without use.

    The reason for this is resonance. When I play a low Bb (233.082Hz) on my Trombone, there are artifacts from the F (339.288) above it and the Bb (466.164) above that... we can keep going for a fair while into inaudible frequencies. Also we can go down to inaudible frequencies again. (the Bb at 116.541 resonates with this grouping as well as others).

    Try taking the lid off a well-tuned piano sometime and play the Bb one octave and one tone down from middle-C. You will notice other strings vibrating. If you inspect closely, you will see that they are the ones I listed above.

    Likewise, inaudible frequencies cause resonation of other notes and thus add to the music even if you can't hear those sounds themselves.

    MP3 stripping out the inaudible sounds does have an effect on your music experience. I find your reply interesting, since you will notice this most with higher-quality speakers.

    -Dan
  • As all of the MPEG formats offer a sliding scale of compression, you should be able to make a video as compact as you like - at the espense of quality.

    What is the minimum size per minute of footage for decent visual quality video, for MP4 and for its predecessor?

  • Re:MP4? Some Definitions (Score:5)

    by xWakawaka ( 187814 ) on Friday June 02, 2000 @09:18AM (#1029683)
    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)
  • You don't need DeCSS to rip video from a DVD, although you can of course use it for that. On the other hand, you can hack up a version of PowerDVD to dump the video to a file, and let your licensed DVD Decoder do the work.

    DeCSS can be used to pirate DVD, but it's hardly necessary.

  • And here's tons of information you should read.. (Score:5)

    by toast- ( 72345 ) on Friday June 02, 2000 @08:16AM (#1029691)
    One of the Mpeg-4 hacks is called Div-X.

    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. html

    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

  • http://www.flashingyellow.com/contest.html

    Here's one for the Mac. I already posted this somewhere around Comment #47 of the origional article.

    There is even source code available at this site.. I don't know how far they are though. Evaluate it at your own risk =)

  • Why are slashdot posting 'DivX is the new mp3' stories masquerading as mpeg4 news? For those who don't know, DivX is simply a hacked version of Microsoft's preliminary version of the mpeg4 video codec, which removes some restrictions inherent in MS's implementation. It enables compression of a DVD movie onto a CD using DeCSS and mp3 for audio. The quality is good, not as good as DVD but better than VHS and pretty watchable.

    A lot of websites seem to be infering that people will distribute these films over the internet ala mp3. This seems unlikely, as not many people have the time or bandwidth do download CD images. What is more likely is that people will rent DVD's from Blockbusters & rip the film to DivX.

  • Re:Codec/Encoders? (Score:3)

    by gwernol ( 167574 ) on Friday June 02, 2000 @08:19AM (#1029696)

    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 [cselt.it].

    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.

  • Don't forget the abortive copy-protected MP4 music format that some rap group tried releasing their music in a year or so ago. It didn't stand for anything at the time--they just meant it to be MP3 incremented by 1.
    --
  • If I'm not mistaken, Microsoft's ASF format has been using MPEG4 for a while now.

    That's been my understanding also. ASF's have been around since before DeCSS (and have been being used to distribute pirated movies for quite some time.) Considering the overall quality of the format it seems ridiculous to use something like DeCSS to pirate stuff--it would be a lot of extra effort that would gain you nothing in the way of quality. To sum it up--this method of DVD piracy has been available to Windows users for at least a year now.

    Anyway, here's an ASF a guy I know made. It's basically a short interview one of the local stations did regarding his new electric car. (Yeah, I got to drive the thing--pretty neat.)

    http://drive.to/mysparrow [drive.to] -- Click "Movies"

    numb
  • As somebody else has already said, it is quite a bit better than LP videotape. However, I don't think that it is up to snuff to SP videotape. If you sit back a bit from the monitor there isn't really anything noticably bad with it. If you sit a bit closer though (as close as I usually sit from my monitor) you can pick out the compression artifacts. Some of them get pretty bad in action intensive sequences. However, the framerate holds up just fine regardless.

    So far as compression ratio, I don't know exactly, but what I was watching was the Matrix ripped from the DVD onto a single CD-R. There was enough spare room on the CD-R to hold the CD-soundtrack as well, and a small bit of other stuff. I guess that would mean that "Saving Private Ryan" in under 350 Mb would look pretty bad compared to the original. Of course, I'm a little picky about a lack of compression artifacts (they jump out at me). So if I was a movie industry exec, I wouldn't get too worried about massive copying of movies using Div-X (although, I suppose if I was an industry exec, I'd be worried about 9th generation copies of somebody taking a camcorder into the theatre with them, so...)

    In any case, the problem isn't going to be transmitting these over the internet (350 meg is a lot to transfer to see a crappy copy of a movie). The big problem is going to be on college campuses, where a profusion of burners and 100mB/sec ethernet makes swapping a couple of gigabytes of files fairly trivial. The copy of the Matrix I saw was legal (space shifting by the owner), but I know that a lot of other movies are available on campus ethernet. I know that at least the Matrix, American Pie, The Phantom Menace, and South Park were all available near the beginning of the semester last year. I have no clue how much stuff will be up next year, but I don't think most people will be heading out to blockbuster to get their favorite movies...
  • If you thought that your favorite four-letter industry groups are pissed now, I can't wait to see what happens next.

    Yay! I can't wait to download 1984 off Gnutella as a form of protest!

  • MPEG4 ~ ASF? (Score:4)

    by TheTomcat ( 53158 ) on Friday June 02, 2000 @08:22AM (#1029722) Homepage
    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?

  • Where have you guys been? (Score:3)

    by BenJeremy ( 181303 ) on Friday June 02, 2000 @11:48AM (#1029729)
    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!

  • Yes, exactly (Score:3)

    by Ian Schmidt ( 6899 ) on Friday June 02, 2000 @09:38AM (#1029730)
    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?

  • Umn, no. CD audio is an uncompressed bitstream that doesn't throw away any of the information. It can be argued that using digital sampling innately loses information from the original waveform, but that's not the same thing. CD audio is full-bandwidth, zero-compression.

    DVD audio I'm no expert on, so I won't even speculate.


    --

  • Re:MPEG-4, not MP4 (Score:3)

    by kaphka ( 50736 ) <1nv7b001@sneakemail.com> on Friday June 02, 2000 @09:47AM (#1029739)
    No need to get excited. From The MPEG Patents FAQ [mit.edu]:
    While in the process of working on MPEG-2, MPEG requested another work item to cover high-definition television standards. However, when MPEG-2 was finished, it was found to satisfy the requirements and MPEG-3 was cancelled.
  • I believe Microsoft's Windows Media Encoder [microsoft.com] software will encode MP4 movies. That would make sense, anyway.

    --

  • Re:Structured audio: Finally! (Score:2)

    by Anonymous Coward
    Isn't this called a "module"?

    See Amiga, 1984.

  • Re:Open source MPEG-4 encoder/decoder? (Score:3)

    by bonehead ( 6382 ) on Friday June 02, 2000 @08:43AM (#1029746)
    No, no, no....

    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 .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.

    (btw, look about half-way down this page [geocities.com] to see what Microsoft has to say about other folks writing software that reads .asf files.)
  • News at 11: Metallica sues the BBC for passing along information about applications that compress videos, allowing the masses to trade pirate copies of Metallica videos previously available only on DVD. Quoth spokesdude Lars, "Well, like, yeah, they could actually be porn films with the names of Metallica videos on them. But admitting that would make us, like, look like idiots. And, um, and justice for all and stuff."
  • I've heard this before, about ASF perhaps using MPEG4. If it's true, I will be very amazed. The quality of MPG4 video compared to ASF is MUCH better. ASF video is around the quality of RealVideo, and VHS beats them both hands down.
  • First, you didn't say which encoder you're using. There is a tremendous amount of difference, and the most popular coders seem to be among the lowest quality.

    Any MP3 coder is going to give you muddy hi-hats at 128kbps. That's because the hi-hat sound is incredibly complex. Getting all the nuances and subtleties perfect requires a lot of bits. At 128kpbs, the encoder does what it can, but can't possibly get it all in there. That's why they sound muddy.

    There is no reason for a good MP3 coder to significantly distort bass sounds. If it's changing a smoothly varying timbre into one that's "flittery," then you're seeing variation from frame to frame, a significant problem with all MP3 coders other than Fraunhofer's newer ones. If you're getting this effect with Fraun, I'd be very surprised.

    The 16KHz cutoff is frequency-based (not exactly an FFT, but similar). Look at some spectrum analysis data - you'll see it's pretty crisp.

    MP3 at 128kbps definitely does distort the sound. That rate is just at the knee - a lot of people can't hear the difference of going to a higher rate, while just about everybody starts hearing the degradation at lower bitrates.

    But my original point was not that MP3 is flawless, it was that the loss is in sonic complexity rather than frequency response. Because the degradation caused by traditional analog processes such as mic's, tapes, speakers, etc., can all be well quantified in terms of loss of frequency response, it's tempting to use the same criteria to judge digital compression. However tempting, though, it's wrong.
  • I suggested looking at spectrum analysis data. Here are some links to follow:


    I think you'll see the crispness of the 16kHz cutoff in these graphs.

  • Re:Quality vs compression level? (Score:4)

    by Vanders ( 110092 ) on Friday June 02, 2000 @12:01PM (#1029764) Homepage
    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....
  • IIRC the PlayStation was basically an SNES with a CD drive that Sony and Nintendo developed together. But Nintendo never used it and Sony got tired of getting jerked around. They built a better standalone unit.

    Since it wouldn't be the original PlayStation (even though that was never sold) it needed a different name. Just as 'extortion' sounds better because of the 'x', the new one was the PlayStation X. Then they dropped the X from the name, but not the acronym.

    The PS2 should have been the PS3 or the PSY of course, but what the hell.
  • Audio and Video compresion are two totaly seperate things. You have MP1, MP2 and MP3 for audio (MPEG1 Layer 1, Layer 2 and Layer 3, respectivley), then you have MPEG1, MPEG2 and MPEG4 for video. MPEG1 on VCD's, MPEG2 on DVD/Digital TV, and MPEG4 which is the codec in question in the article. You can combine the Audio & Video codecs as you wish, but most MPEG1 VCD's use MP2 or MP3 compresion for the audio....
  • Although 350MB is still ridiculously large, this will lend credence to the claims that DeCSS is aiding piracy.

    A good counter-argument to this is simple.

    When you encode video at such a low ratio, you lose a LOT of quality. I seriously doubt that I could tell the difference between VHS and DVD when encoded in this format.

    People trade movies that were recoded with 8MM Video, on a tripod in an empty theatre for that matter. If you want the quality you buy the DVD.

    Same as music. In my car, with the factory sound system (Chrysler makes some sweet Inifinity speakers), I can DEFINATELY tell the difference between tracks I've burned, from compressed and uncompressed audio. If you want the quality, you buy the CD.

  • Remember that a VHS video recorder also significantly reduces picture quality. Yet I'd bet that 90% of the public not only is not bothered by it, they are not even aware of it.

    I think this is a great point. Its amazing how many people have put up with the often stunningly low quality of many consumer VHS machines. What is interesting is how DVD has started to take off. A number of my (geek and non-geek) friends have got DVD and boy, they do notice the lack of quality in VHS after that.

    I suspect as more folks get exposed to high quality video sources (DVD, Net, Digital cable done right etc.) their tolerance for poor quality VHS will drop.

  • DivX is the name of the codec based on Microsoft's implementation of MP4. It's not the player.

    Also, the statement "no sources, so not for linux" is incorrect - just because you have source doesn't mean it's for linux.

    The links are correct though...
  • Be realistic: 128kb MP3 sounds like early MiniDisc players running ATRAC1 i.e. shite. On a 1" PC speaker you can't tell the difference, but put both your MP3 stream and your CD stream through a decent audio interface (thereby removing variation in the D/A) and out through a decent amp and speakers rather than a £50 "100W multimedia audio system" and tell me you can't tell the difference.

    Or maybe I've just got golden ears - but sadly :-( I don't think so
    --
    Cheers

  • "The Codec" starring Keanu Reeves

    "Woah... I know algorithms

  • This didn't happen on the web, but when I lived in Bahrain (small island state next to Saudi Arabia) a few years ago we usually got to rent movies either a month before it hit the theatres or right after.

  • Ok I have watched a James Bond - The World is Not Enough movie. It was on SINGLE CD - 640Mb. The quality was more than what I expected - good, watchable, comparable to video tape.

    The player was only for Windows (and there is one for Mac I believe. I _think_ there is no player for Linux / UNIX. (_please_ email me if there is one) David Theactual James Bond film was so shit (first time I saw it) I could not believe it - I mean shit compared to other James Bond movies, otherwise it was good action movie.

  • Re:MPEG-4, not MP4 (Score:5)

    by generic-man ( 33649 ) on Friday June 02, 2000 @08:51AM (#1029794) Homepage Journal
    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."
  • CD audio throws away *ALL* of the information below 20hz and above 22,000hz.
    --

  • DivX is back but this time it's good. (Score:4)

    by toppk ( 135746 ) on Friday June 02, 2000 @08:02AM (#1029799)
    It is the name of the freeware mp4 player (no sources, so not for linux). Get it here:

    http://divx.forpresident.nl/
    http://divx.ctw.cc/

    I didn't make them links, so they wouldn't get /.'d as fast ;)

    Have fun. -toppk

  • You're on the right track, but you're wrong. The concept you're thinking of is the "contrapositive". Given a statement "A implies B", there are three related statements, the inverse ("Not A implies Not B"), the converse ("B implies A"), and the contrapositive ("Not B implies Not A").

    The statement "A implies B" is a true statement when A is false, or when A is true and B is also true. It's a false statement when A is true but B is false -- namely, A did not actually imply B. This is best illustrated with a truth table:


      • ABA->B
        --------------
        FFT
        FTT
        TFF
        TTT

    The contrapositive of the original statement is always true when the original statement is true, and is always false when the original statement is false. In other words, a statement and its contrapositive are logically equivalent statements. So, when a given statement is true, you can state with conviction that its contrapositive is true. Likewise, when a given statement is false, you can state with conviction that its contrapositive is also false. The two are equivalent statements.

    Consider the truth table for the contrapositive, as compared to the original statement:


      • ABA->B !B!A!B->!A
        -----------------------------
        FFT TT T
        FTT FT T
        TFF TF F
        TTT FF T

    For example, take the statement "If it's raining, the sidewalk must be wet." Here, A is "If it's raining", and B is "the sidewalk must be wet." If we accept this as a true statement, then we can say confidently "If the sidewalk is not wet, then it must not be raining." We cannot say, however, "If it's not raining, the sidewalk is not wet", or "If the sidewalk is wet, it's raining" -- at least, not on the basis of the original statement alone.

    In your example, you stated "No white feathers, so not a duck." A == "No white feathers," and B == "not a duck". The contrapositive would be "If it's a duck, it has white feathers." In other words, "All ducks have white feathers" is an equivalent statement to the initial statement "No white feathers, so not a duck."

    Got that?

    --Joe
    --
  • Call my post a flame, troll, off-topic, whatever, but certainly not redundant. Where else did you see a post ridiculing this haiku? I'm just tired of seeing these poorly written haiku all over slashdot lately, and your moderating down a dissenting voice isn't helping any.

    Best regards,
    Daniel.

    --

  • 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!

  • uh-oh (Score:3)

    by vsync64 ( 155958 ) <vsync@quadium.net> on Friday June 02, 2000 @08:04AM (#1029815) Homepage
    The timing on this could not have been worse. Although 350MB is still ridiculously large, this will lend credence to the claims that DeCSS is aiding piracy.

    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...

  • Re:hmm (Score:2)

    by 575 ( 195442 )
    "Clue", those shining gems
    The gods bestowed them to man
    Our friend slept that day
  • What does it look like? I can already encode "Saving Private Ryan" in under 350mb - the technique is called low framerates and low pixel resolution. How watchable is it? Does it slideshow in action intensive sequences? What's the average compression ratio?

    Any of you slashgeeks want to fill in the details?

    --Shoeboy
    (former microserf)
  • I disagree. This guy not only is writing some occasional gems, but his haiku responses to his criticism are effing brilliant.

    Also his restraint in still posting at 1, even though my calculations show he's got to be past 20 karma by now. (Unless he's been a dick in moderating.)

    --
  • There's more information in a digital recording

    Which is bullshit, of course. ;)

    Analog assures you an infinite number of data points. Digital limits you to the precision of the A/D doing the initial recording. Any finite number is eclipsed by infinity!!
  • 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? ;)

  • However, that's also true of CDs, and DVDs for that matter.

    Yet most people can't tell the difference, or think a CD sounds better than an LP.

    Technology marches on, and I think we're better for it.

    --

  • VHS (Score:3)

    by ucblockhead ( 63650 ) on Friday June 02, 2000 @08:05AM (#1029842) Homepage Journal
    Remember that a VHS video recorder also significantly reduces picture quality. Yet I'd bet that 90% of the public not only is not bothered by it, they are not even aware of it.

    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.

  • Re:Great. Something else for the MPAA to kill (Score:3)

    by hattig ( 47930 ) on Friday June 02, 2000 @08:06AM (#1029843) Journal
    Something else for the Universities to Ban!

    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?

  • Ever hear of IE for UNIX and how bad it sucked? Don't bother with Media Player on the Mac.

    I tried playing one of these compressed clips on the MS Media Player for Mac, and it was dog slow and dropped frames like mad. It was totally unusable on a 350 MHz blue G3 with 196 megs RAM. I've seen MUCH better video using QuickTime on a PowerMac 6100... at 60 Mhz.

    This is just a MS play at locking in the pirate community and using that momentum to displace legitimately used codec.

    There are techniques such as smoothing that improve the usual compression rates of standard MPEG... it's just that bare bones software does not offer it. What Linux needs is something like Media Cleaner, for MPEG.

    Q: (Why is it that most of those MPEG music videos, played under Linux, have all bad colors and bad sync among the compression tiles? I've never seen a MPEG play fine even on a fast Linux box, but they work fine in Windows ro the Mac)??

  • uh... VideoCD Whitebook specs don't allow for either Layer 2 or 3 audio.

  • Haiku (Score:5)

    by 575 ( 195442 ) on Friday June 02, 2000 @08:07AM (#1029848) Journal
    MP4 at hand!
    Salvation! ev'ry South Park
    On one shiny disc
  • A good way to find out is to see how long it is until they find that the MP4 format infringes on their copyrights.

    My guess? MP4 goes the way of the dodo in 6 mos. BUT, a newer, higher quality version will come out in its place shortly thereafter. The only difference is that the new one will have some poor encryption all over it and a spinning MPAA logo at the bottom of the frame.

  • It's much nicer than VCD, which has been floating around for a while now. A Gnutella search for DivX will answer all your questions.
  • Until we(as a commercial populace) get bigger pipes, this is the sort of technology that will be popular. Even with the advent of bigger and badder video cards, this form of compression may fit very well with the ability of many people's systems. Someday we will all live in a fiber optic world with realtime streams that aren't compressed...but till then..
  • Ah. A good point, but somewhat a change in context. CD encoding does have a top-end brickwall of ~ 22KHz, and sometimes has a rumble filter of below 20Hz (although that information usually self-recreates to some degree through subharmonic interactions of speakers).

    This information is outside the range of hearing, theoretically (although we can argue all day about whether it's important; I'd probably agree that it was, but only very slightly so relative to, say, 1KHz); MP3 compression actually loses information that's in the unarguably audible frequencies. A perfect encoding algorithm would only lose "subperceptible" information, but I haven't heard a perfect one yet at anything less than about 256k bitrate, roughly 1:4 compression, like used on DCC and MiniDisk, only better. 128k and below cause perciptibly audible distortions to the original material; CD doesn't.

    And for that matter, almost ALL consumer media throw away the 20-20000 range you're talking about -- cassette tops out at about 18k on a REALLY good day, DAT gets up to 24k if you're doing everything right, and so forth. The new 96/24 pro standard can get frequencies up to about 48kHz, and at 24-bit resolution, but that always gets mastered down to 44/16 at best, and then typically played back through bookshelf speakers that only go down to 45Hz and up to 18.5k, so 20Hz and 20kHz is kind of moot unless you're in the mastering studio or have built a $15,000 listening room in your home.


    --

  • God damn! If you think mp3 sounds like crap, use something else! For most people, and this would explain the HUGE following mp3 has, they either can't hear the difference or don't care. I can't tell the difference when you take a mp3, decode to wav, and then burn the wav to a CD and play on a high quality CD player. I suspect a lot of the problems people have with sound quality are because their computer audio is crap, or their encoder is crap. Or the CD player used to rip the disc is crap.

    IMHO, I love mp3, it sounds great, the quality is incredible - I have a $2000 setup in my car, I use a diamond rio for the playback, and it's crystal clear. The rio sounds a lot better than any of the sound cards I've heard. (on the stereo - those headphones are crappy). The rio sounds good on my sony reference headphones at work, too.

    You might have a different opinion. Have you ever had your hearing tested to see exactly what you can hear? Most people (myself included) have a hard time with sounds over 18kHz. Some people are a lot worse.

    If you don't like it, DON'T use it. You didn't pay anything for it. If it's crap in your mind, just use something else, or make it better! Bitching doesn't help anyone.

    Mpeg-4 looks sweet, too - but the video source makes *all* the difference. Just pointing out there are a LOT of problems that could happen besides the codec.

    Kudos

  • So, mp4.com is owned by mp3.com!

    Domain Name: mp4.com
    Administrative Contact, Technical Contact, Zone Contact:Hostmaster, MP3.com (HM3936-ORG) hostmaster@MP3.COM

    So it looks like the folks at mp3 will be going through some interesting times again! They will have been thru the legal hassles again, at least they will have experience. Okay, next:

    Domain Name: mp5.com
    Administrative Contact, Technical Contact, Zone Contact, Billing Contact: Eom, Sang Sik (SSE20) kdns@KDNS.COM
    Korea Domain Name Services

    I didn't check all the way to mp666.com..but

    Domain Name: mp666.com
    Administrative Contact: Lucey, S Griffin (SGL32)
    griffin@TGG.COM
    The Gryphon Group, LLC

    I don't think I wil be alive to see this one....maybe you don't have to be!
    -rvr
  • It's not that simple. To store an analog sinewave at 1000Hz digitally, 44.1kHz sampling is WAY more than adequate -- you have 45 samples along each cycle of the sine wave to interpolate between. Unless you're expecting sudden single-cycle 80,000Hz spikes in the middle of this wave, you're losing nothing; reconstructing a waveform from sporadic individual points is high-school algebra stuff.

    When you get into more complicated waveforms, with higher frequencies, there's the possibility for distortion as you approach the Nyquist limit of half your sampling rate. This is one of the reasons that recording and mastering studios have moved to a 96kHz sampling rate, even though it gets mastered down to 44.1 later.

    So, yes, there's a subtle argument to be made that sampling an analog waveform can cause loss of information (although it doesn't necessarily cause that loss, per my sinewave example above), but at some point, this becomes moot even at the analog level, because there comes a level past which we're talking about information that CANNOT move the human eardrum, and even if we want to get more pedantic than that, energy itself is quantized, so if your sampling rate is fast enough, you're going to bump up against Planck time in measuring the motion of the molecules.

    Meaning there's no need for "infinite" storage space to get an analog waveform perfectly, just really large amounts, because an analog waveform is not actually infinitely complex; Fourier proved that a long time ago, and failing all else, Planck showed us that even nature is quantized at a super small level.
    --
  • Did anyone notice that mp3.com [mp3.com] already owns mp4.com [mp4.com]?

    Their legal troubles will never end!!

    --
  • The name has meaning
    Rejoice in revelation
    Grasp the obvious
  • Because if it is, I expect the film industry will do its level best to see it made inaccessible to open source, since it might result in a "filmapster" at some potential future time. Besides with digital video tech becoming cheap, they're likely worried about the people they see as "mere consumers" usurping their industry.

    If any of you techies out there are good at video codecs, perhaps you could look into helping the Ogg project's video compression design, so we can have a really good patent proof and free-to-use film codec.
  • I know, i realised that after i hit submit. I have no idea what i was thinking when i put those two together :)
  • Good question. If the quality is decent at 350MB per hour, that fits your average movie (1:45 == 612.5MB) on a CD. Of course you would have to dump the previews, commercials, etc.

    -L

  • MPEG-4, not MP4 (Score:4)

    by KFury ( 19522 ) on Friday June 02, 2000 @08:10AM (#1029889) Homepage
    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

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