You can't change a picture's initial resolution if it's not the size fitting for a wide screen.
wide screens usually have a 16:9 ratio between their width and height.
that's why when you watch a wide screen DVD on a regular TV (4:3 ratio)
you don't see full-screen and have black 'stripes' above and below the image.
if you have a picture that was meant to be displayed on wide screens it would probably not need 'stretching'.
just like calvin_il said
you cant put a picture that doesn't fit wide screen on full screen mode unless you stretch it
if the picture doesn't have the same ratio as the wide screen than the only solution is to add her strips where ever there is a gap so it will be wider/taller and wont be distorted when you stretch it to a full screen
try to use photoshop or another image editor to add those stripes (or if possible try with the stamp tool to duplicate parts of the picture so it will get wider enough etc)
how do you get a computer video not to streching the image on a widescreen tv
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