Re: kosher jpgs

On Fri, 31 Oct 2008 12:33:22 -0700, Roedy Green wrote:

I noticed that winzip sometimes issues a warning message that it can't
compress a jpg with its proprietary jpg compression method. This
suggests that some of my jpgs are not completely kosher.

This lead be to wonder if there is some java code to detect if jpgs are
completely kosher, ditto pngs, and possibly correct them if not.

Alternatively, perhaps some utility will do this.

I also wondered what it might be about the images that Winzip does not
like.

This made me wonder.. how much more can you really expect to compress
a .jpg file? It is already compressed using a lossy compression
algorithm. Would taking on another lossless compression algorithm on top
really buy you much if anything?

--
Kenneth P. Turvey <kt-usenet@xxxxxxxxxxxxxxxxxx>

I think the world is run by C students.
-- Al McGuire
.

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