Questions and postings pertaining to the development of ImageMagick, feature enhancements, and ImageMagick internals. ImageMagick source code and algorithms are discussed here. Usage questions which are too arcane for the normal user list should also be posted here.
I know that, I want to change the depth 24 to 8 , reduce image size.
It's also a way to adjust the quality. I want to see if there are other ways to solve this problem.
"depth(8)" will reduce the image to 8 bits/channel/pixel. Perhaps you want "-type Palette". Some other function will do that. Sorry, I don't know IM for Java.