Overlaying an Image over a white background only
Posted: 2009-09-28T00:26:40-07:00
Hello
Is it possible overlaying an image over the white region of another image?
Suppose I have two images: large.pnm (500x70px) and copyright.png (16x8px)
The first large image contains only text: so it has only two colors (black for the text & white for background).
I would overlap copyright.png over a white part of large.pnm.
So I have to determinate (and locate) 16x8px of white part in large.pnm...
Is it possible to do using a single comman line? How to do?
I have found this pseudo solution to check white regions, but it is too elaborate and require several system calls.
Got anything more simple?
Thank you so much for replies
Is it possible overlaying an image over the white region of another image?
Suppose I have two images: large.pnm (500x70px) and copyright.png (16x8px)
The first large image contains only text: so it has only two colors (black for the text & white for background).
I would overlap copyright.png over a white part of large.pnm.
So I have to determinate (and locate) 16x8px of white part in large.pnm...
Is it possible to do using a single comman line? How to do?
I have found this pseudo solution to check white regions, but it is too elaborate and require several system calls.
Code: Select all
exec("convert large.pnm -crop 16x8+0+0 TXT:out.txt");
exec("convert large.pnm -crop 16x8+16+0 TXT:out.txt");
exec("convert large.pnm -crop 16x8+32+0 TXT:out.txt");
... etc ...
exec("convert large.pnm -crop 16x8+32+8 TXT:out.txt");
exec("convert large.pnm -crop 16x8+32+16 TXT:out.txt");
... etcThank you so much for replies