"Generating a thumbnail
Creates a thumbnail of original.jpg iff it is bigger than 100x100 in size. This also forces the aspect ratio to stay the same. Append a ! to the 100x100> to force an aspect ratio override. The convert "*" removes profile information so you end up with a smaller file.

convert -scale '100x100>' profile "*" original.jpg output.jpg

Sticking one image on another
sticks watermark.gif on top of atest.jpg starting at 20, 300 and outputs to aout.jpg. Note, the -geometry specifier has to be at the end because of a bug

composite -compose bumpmap watermark.gif atest.jpg -geometry " 20 300" aout.jpg

same thing, but orients it at the south
composite -compose bumpmap -gravity south watermark.jpg neon1.jpg aout.jpg"

1381 Also posted to: Home page . At: 8:26:27 PM  . .
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