Does the term MPEG4 mean anything by itself anymore?

Discussion in 'Amateur Video Production' started by Ken Maltby, Feb 4, 2006.

  1. Ken Maltby

    Ken Maltby Guest

    Has MPEG4 become like "AVI" a term that needs to be
    qualified to have any real meaning?

    For many MPEG4 is the format of the video on their cell
    phone or iPod. (Really small image size and very highly
    compressed)

    For some MPEG4 is the format to use with HD material
    and still have reasonable sized files. (Large image size and
    highly compressed)

    For others MPEG4 is the format that their downloaded TV
    episodes comes in. (Small image size and very highly
    compressed )

    For me, I use MPEG4 to store DVD quality video in smaller
    files. (D1 image size and very highly compressed)

    So when you find out that a poster's question : "How do I put
    my AVI on a DVD? - is really "How do I put my MPEG4 video
    on a DVD?" You still have to establish whether this is cell
    phone video, HD video, or something in between we are talking
    about.

    Of course if all that is needed is the conversion then responses
    like "Use 'XYZ' program and it will do all the work for you" ,
    make some sense. But many times the question is being posted
    because such simple approaches are not working.

    I guess it is really a mute point, as just like trying to get people
    to stop using the term AVI, by itself, as if it meant something;
    there is little that can be done about it.

    Luck;
    Ken
     
    Ken Maltby, Feb 4, 2006
    #1
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  2. Ken Maltby

    Rick S. Guest

    MPEG has always been nothing but sets of file specifications, just
    like AVI. For any individual file, neither of these terms specify
    anything about codecs, or even which format within the
    specification the file uses.

    MPEG-4 simply has far more options for allowable formats,
    that's why it seems more ambiguous than earlier MPEG
    specifications.
     
    Rick S., Feb 4, 2006
    #2
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  3. Ken Maltby

    DanR Guest

    I've seen posts here that refer to AVI as only a container of sorts. I never
    understood what that meant. For us at my work... we refer to AVI as
    "un-compressed AVI" and define it as an uncompressed video file to be
    manipulated after encoding from video tape. We could encode from tape directly
    to a Windows media file for example but if we want to use a 2 pass method to
    create the Windows media file we would use our "uncompressed AVI" setting to
    first get the video on the computer in as pure a state as possible. Or we may
    want multiple formats so the uncompressed AVI file is imported into Cleaner and
    it will batch out multiple formats. So as users of the encoding software,
    Stream, we just choose "un-compressed AVI" from a menu and encode. What are the
    "file specifications" for un-compressed AVI? Whatever they might be we don't
    think about them. What am I missing?
     
    DanR, Feb 4, 2006
    #3
  4. Ken Maltby

    Jukka Aho Guest

    An AVI file can contain uncompressed data, but it can contain compressed
    data as well. (What defines the actual raw storage format of the video
    data? The codec that you use. AVI just defines a common framework in
    which various different codecs can store their data.)

    Uncompressed video data can be formatted and stored in the memory in
    many different ways. Hence, there are several possible types of
    uncompressed AVI. For example, you may have an uncompressed AVI file in
    the 24-bit RGB format, or another uncompressed AVI file in YUY2 (YCbCr
    4:2:2) format. Both are uncompressed (i.e. the plain pixel data is
    readable from the file without any special algorithm), but the data is
    still in a different format.

    See the following pages for more information about uncompressed formats
    that are commonly used for video data:

    <http://www.fourcc.org/yuv.php>
    <http://www.fourcc.org/rgb.php>
     
    Jukka Aho, Feb 4, 2006
    #4
  5. Ken Maltby

    Ken Maltby Guest

    Just did a Google of "AVI" and came across this; which provides
    a good grounding of AVI's development.
    www.jmcgowan.com/avi.html

    Luck;
    Ken
     
    Ken Maltby, Feb 4, 2006
    #5
  6. It means that "AVI" (and "WAV" for that matter) are two (of
    several) kinds of RIFF (Resource Interchange File Format)
    files.

    http://support.microsoft.com/default.aspx?id=kb;en-us;Q316992

    RIFF files contain a code at the begining of the file identifying
    what is in the file and how it was encoded (i.e. which codec
    was used). Without this codec information (and a compatible
    codec installed on your machine) the contents of the file are
    random, indecipherable ones and zeroes.

    The codec identifying codes at the head of RIFF files are
    called a FourCC codes and the www.fourcc.com website
    has a reasonably complete (>200) listing of them. Click on
    the "Video Codecs" page.
    Of course you can use whatever terminology works for
    your co-workers. But in reality, AVI files can contain any
    of several hundered different encodings (codecs), only a
    very few of which are actually "uncompressed". Most of
    the reason for codecs is to implement compression since
    uncompressed NTSC video takes ~70GB per hour and
    few of us want to deal with that!
    OK. But unless your files are 68.5GB/hour, chances are
    very good that your "uncompressed AVI" files are actually
    compressed with some sort of codec. As long as nothing
    changes, you are OK not knowing which codec you are
    using. But if your hard drive crashes and you have to re-
    install everything, or if you want to gen up annother PC to
    handle additional workload, or you want to send your AVI
    file to somebody else, you will need to know what codec
    you are using.

    A (free) utility that many of us find useful is "Gspot" from
    http://gspot.headbands.com/ It will not only tell you which
    codec is used for a given file, but it will also identify all
    the codec(s) installed on your PC which can decode it.
    There is no "un-compressed AVI" file specification. Because
    "un-compressed AVI" is undefined. Download Gspot and
    use it to identify which codec you are using. The information
    you learn from this exercise might just save your bacon in
    the future.
     
    Richard Crowley, Feb 4, 2006
    #6
  7. "Ken Maltby" wrote ...
    I don't see it as a moot point. It is critical to know what
    file extension people are dealing with. If it is "AVI" then
    we know that it is a container file and they must use Gspot
    or something to discover the FourCC code and identify
    which codec was used.

    And "MPEG4" at least gives you a starting point from which
    to launch a more detailed investigation about exactly what
    is the nature of the file.

    OTOH, I agree that as video (and audio) gets more into the
    hands of dilettantes (without meaning anything pejorative!),
    terms like PCM and AVI and MPEG are bandied about
    without regard to what they mean (or what they imply about
    deeper levels of information).
     
    Richard Crowley, Feb 4, 2006
    #7
  8. Ken Maltby

    DanR Guest

    Thanks all for the info. I will use the gspot utility and the links to learn
    more about what we're doing.
    I was under the impression that uncompressed NTSC is about 96GB per hour. We are
    usually dealing with 30:00 spots or other very short programs when using this
    un-compressed format. Our Avid editors generally capture at 2:1 and once in a
    blue moon will use un-compressed.
     
    DanR, Feb 5, 2006
    #8
  9. Ken Maltby

    RS Guest

    Well said Ken. But I fear you will end up tilting at windmills here. The
    explosion of multimedia into the average persons life means that groups
    such as this, which were once the domain of a smallish bunch of video
    hobbiests, is now the 'ask first, look for yourself later', home for
    bittorrent pirates who want the easy button for moving all or part of
    whatever they have aquired onto any device they own, with the push of a
    single button.

    The keep saying that todays kids are so 'tech savvy', if by 'tech savvy'
    they mean, 'knows where the on switch is' then I agree, but overall,
    I've found that todays kids don't really know much about any of the
    gadgets they play with.
     
    RS, Feb 6, 2006
    #9
  10. Ken Maltby

    Ken Maltby Guest

    Sometimes I feel more like a guy trying to keep the windmill
    turning, who hears the hoofbeats getting louder and louder.

    I remember early critics of SciFi that complained about stories
    that had barbarous hoards arriving in spacecraft. Even Asamov's
    "Foundation" took some criticism for it's handling of the spread
    of rediscovered technology. I wonder what they would say if they
    could see the products of our educational ( actually more "social
    development" than education) institutions wielding our current
    technology? I have seen ample evidence that today's "Stoned
    Slackers" have no problem posting to a NG.

    Luck;
    Ken
     
    Ken Maltby, Feb 6, 2006
    #10
  11. Ken Maltby

    RS Guest

    A couple of my favorite SciFi short stores are by C.M Kornbluth "The
    Marching Morons" and "The Little Black Bag" imagine a world exactly like
    that. Where techology has advanced so far that an illiterate moron can
    be a doctor, and is.
     
    RS, Feb 6, 2006
    #11
  12. On 2/6/2006, Ken Maltby managed to type:

    Your writing here reminds me of a metaphor I've used for years with
    much the same intent: "The Visigoths are coming over the hill".
    Meaning, of course, that Rome is about to be sacked or whatever...

    Imagine how I felt a couple of years ago when here in California we
    elected an Austrian (Latin for Ostrogoth, more or less, which was a
    division or neighbor of the Visigoths) as governor!

    Gino
     
    Gene E. Bloch, Feb 6, 2006
    #12
  13. Ken Maltby

    Ken Maltby Guest

    The scary thing is that there are those who view that as a good
    thing. They see this as a worthwhile objective for technological and
    social development. But what is really scary, is that they are the
    ones in control of our educational institutions.

    In SciFi terms; contrast that with Gordon R. Dickson's "Wolfling"
    where a society succeeds by educating its members to a level that
    any of them could recreate their civilization; technology and all. They
    each know how everything works.

    As a goal, I prefer the self-sufficiency of Dickson's approach to the
    most capable/functional, technological illiterate approach. Not that we
    are presently capable of absorbing the knowledge needed, it just seems
    odd that we place those who show any interest in "how things work" on
    a very low social rung, as nerds or geeks. Intellectuals have never
    accepted the practical man into their ranks, be they "Scientists" or
    Technicians.

    Luck;
    Ken
     
    Ken Maltby, Feb 6, 2006
    #13
  14. Well, SOME of it is good. 100 years ago, only mechanics drove
    automobiles because they weren't reliable enough for regular folk
    to drive through the countryside. Several other examples of this
    kind of thing where either the technology improved, and/or where
    the knowledge/ability became commonplace.
     
    Richard Crowley, Feb 6, 2006
    #14
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