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Old 3rd February 2006, 15:27   #13  |  Link
yaz
n00b ever
 
Join Date: May 2002
Posts: 627
Quote:
Originally Posted by bkman
But why is it that the "true" DAR includes black bars? Surely they are not part of the actual image, and it should be resized to 4:3 without them.
definitely not. really, black bars are not part of the movie but they are part of the image/stream. they are used to maintain the stream dimensions which must(!) be always 720x576 for pal dvd and 720x480 for ntsc dvd. whithin this fixed-size box u can place any stream having quite arbitrary dimensions. (say, 654x321 is ok, if its 'bordered' to 720x576/480)
this box is resized during the playback according to the 'par' value (which simply defines how much it should be streched horizontally) calculated as showed above.

don't ask me why is it figured out like this but that's what we have

Quote:
Originally Posted by bkman
Like if you cropped to 704x576 to give the full image, shouldn't that then be resized to 768x576 (instead of 751x as with counting the black bars) to give proper AR since the original T.V. show was 4:3 (and had no black bars originally)?
hmm ... can't get u here, but ... the stream must be shown 4/3 on your screen/display/tv but how it's stored in a file/dvd/whatever depends on the intention of the creator. there are possibilities (see above).
about the borders ... maybe they just cut away some dirty/bleeding/shifted/ringing/... pixels round the pictures for getting better compression. dunno

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