Re: Extracting a region from a Jpeg

Jeff wrote:
Hi

Does anyone know if it would be possible in principle to extract a rectangular region from a Jpeg file without decoding the pixels - or put another way could a jpeg file be cropped without first decoding it? I'd be prepared to accept that the width and height of the rectangle had to be aligned multiples of 8.

Try looking at jpegtran. Does (in the latest version)
what you want, and the source is available.

http://sylvana.net/jpegcrop/

BugBear
.

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