in reply to BMP: Drawing or photograph?
Personally, I find ImageMagick to be hard to install, and find Imager far more pleasing and transparent in its API.
I have used ImageMagick, and it is very powerful. But its methods and parameters are underdocumented IMO, and there are subtle changes in behaviour between minor versions that make me prefer Imager.
Of course, the external helpers for ImageMagick make it highly convenient when one needs to convert from Postscript (or PDF?) to a raster image. But that's not my use case.
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