The Independent JPEG Group's free implementation of JPEG (which is required for JPEG support in most any package, including ImageMagick) includes a program named "cjpeg" for doing exactly this. "djpeg" does the reverse.
The PerlMonk tr/// Advocate

In reply to Re: perl script to convert .ppm image to .jpeg image by Roy Johnson
in thread perl script to convert .ppm image to .jpeg image by Anonymous Monk

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