Re: image offset

On Thu, 11 Jul 2019, mick crane wrote:

> I think what happens is $image -> crop
> is some  memorized code that says take all these pixels from the x,y, width 
> and height and save just those in a way identifiable as an image file.
> But what is this offset thing ?

Sometimes it is useful to remember the offset that the cropped image 
came from.  It is sometimes an annoyance that PNG (and some other 
formats) remembers this and software may use it unexpectedly, but 
sometimes it is of great benefit.

There is a way to crop an entire image into a sequence of image tiles, 
and in this case is very useful for each tile to remember its original 
offset.

Bob
-- 
Bob Friesenhahn
[email protected], http://www.simplesystems.org/users/bfriesen/
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