Is DV or MiniDV format lossy?

Discussion in 'Video Cameras' started by kash, Jul 13, 2003.

  1. kash

    kash Guest

    Is the DV or MiniDV compression format lossy in any way whatsoever
    or is it non lossy like for example the zip format?

    Tia
     
    kash, Jul 13, 2003
    #1
    1. Advertisements

  2. kash

    Ed Fielden Guest

    It's both lossy and non-lossy. Video is compressed in a lossy way, with a
    compression of 1:9.1
    Audio is uncompressed (i.e. non-lossy) PCM. Overall, the file will have a
    compression ratio of about 1:8.6

    To be honest, the compression barely makes a noticeable difference to the
    video. I don't know the ins and outs of exactly _how_ the video is
    compressed, but it doesn't seem to make it look too ropey!
     
    Ed Fielden, Jul 13, 2003
    #2
    1. Advertisements

  3. kash

    E. Greenbank Guest

    Could you possibly explain this ratio compression business to me. I've never
    quite understood what its on about.
     
    E. Greenbank, Jul 14, 2003
    #3
  4. As it was explained to me by a Sony engineer when DV first came out,
    full frame uncompressed digital video is 270Mbit/sec. DV reduces the
    area of the frame slightly and reduces the colour sampling to 'half'.
    That alone brings the data rate down to around 125 Mb/s, those bits are
    dumped never to be seen again. The remainder is 5:1 compressed to the
    familiar 25Mbits/sec. So there is an element of hype in the 5:1 claim,
    it could be argued it's nearer to 10:1. But it works well.

    The audio is not compressed at all.
     
    Malcolm Knight, Jul 14, 2003
    #4
    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.