Quote:
Originally Posted by hello_hello
.....It seems to me most (PAL 4:3) DVDs use a PAR of 16:15 regardless of whether the extra 8 pixels each side contain image or not, but I'm still trying to understand this properly.
|
Well, one simply has to
accept that anamorphic DVD's can use the Generic or ITU PAR (or a mod-16 compliant approximation of it).
My experience: The majority of those (older?) DVDs which have about 8 pixels borders left and right follow the ITU PAR. This is
no proof however, as the picture could also have been scaled to accommodate overscan. Those DVD with an active picture width of 720 (no left and right borders) are likely to follow the generic PAR.
One can try to do the "circle test" to conclude on the PAR (unfortunately a reliable circle may not be readily found in the source), or one can try to 'reverse-engineer' the PAR starting from the Movie Aspect Ratio (like 2.39, 2.35, 1.85, 1.7778 etc. as indicated on the cover or found on imdb).
What the playback device eventually does with it is a totally different story. For example, my standalone plays ITU DVDs via HDMI including the black borders left and right as 4:3 or 16:9, means the
active picture is in fact 2.5% too narrow, wheras my old DVD player using the SCART interface to an analog TV plays these DVDs undistorted ...