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.
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JPEG is a lossy format. This means the compression code changes the pixel values when the file is written. Lower quality number gives better compression but causes more change.
The data is lost. You can't get it back by reading the JPEG and saving the image to another format.
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