DV video compression artifacts - Reduce with post-processing?

Discussion in 'Amateur Video Production' started by Marc Brown, Feb 26, 2004.

  1. Marc Brown

    Marc Brown Guest

    I've thrown this one back and forth a bit on other forums. Basically, I'm
    after the best possible quality for my upcoming home movie-to-DVD projects.
    Determining the best Mpeg encoder and DVD authoring software were a couple
    of the steps I took. Now I'm looking at reducing image degradation as
    much as possible.

    I'm quite familiar with the phenomenon that encoding video that already has
    Mpeg-like artifacts will tend to MORE than double the prevalence of
    compression artifacts. So it makes a lot of sense to take some steps to
    reduce those artifacts, since the result will be, in theory, better than
    twice as much improvement over what you get without taking such steps.

    My (newbie) research eventually revealed what sort of video DV actually is.
    Constant bitrate, discreet cosine transform (DCT)-aided lossy compression.
    Keyword, there: Lossy. Of course it becomes quite obvious the video is
    lossy just by watching it. But it's nice to be able to put words to the
    observation. In fact, I find it tempting to compare DV compression
    artifacts to those prevalent in standard DVD Mpeg2. They appear similar
    to me, enough so that if I had been told DV is really Mpeg2, I would not
    have been surprised.

    The point is, the artifacts are frequently quite nasty. Ways to reduce
    them must surely have been pondered by plenty of folks.

    So, we have Mpeg2 and the various Mpeg4 codecs out there, and we have this
    thing called "post-processing" which one can typically access from within
    their media player of choice. It specifically addresses compression
    artifacts like blockiness or "ringing", taking advantage of the known
    interdependency between frames of video in any such encoding, and works to
    reduce them. The process is somewhat CPU-sensitive but not so much as to
    make it infeasible for processing on the fly.

    As one might expect, this generally produces a more desirable result than
    simply taking the whole video and passing it through a blur filter or
    whatever.

    So, the obvious question: What software exists that can perform this sort
    of tailored compression artifact reduction on DV video? (To avoid any
    possible confusion, I'm talking about the video one gets when they
    "capture" it from their MiniDV camcorder via firewire, onto their hard
    drive.) I don't in the least think it's a far-fetched concept. This sort
    of post-processing is, after all, quite mundane for most other video
    formats. And it does a good job. Certainly, better than the *absolutely
    nothing* which is probably what people generally do to their DV video
    before burning it off.

    Thanks for reading!
     
    Marc Brown, Feb 26, 2004
    #1
    1. Advertisements

  2. Marc Brown

    Bariloche Guest

    If what you want to do is some kind of pre-processing, akin to what
    players do as post-processing, you can try VirtualDub and Avisynth,
    and their many plugins/filters.
     
    Bariloche, Feb 26, 2004
    #2
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.