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A comment on Impressive JPEG Recompression. Parent comment

Re:Impressive JPEG Recompression by waitwhat on Tuesday August 30, 2011 @05:43AM (#2940727)
But the compressed version actually exposes more detail.

No. It really doesn't.

It adds a couple of visual filters (brightening, sharpening) before recompressing, but these don't "expose more detail", but rather all three steps actually introduce additional errors. Errors that trick they eye into seeing a "better" image, but errors nonetheless.

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Re:Impressive JPEG Recompression by sharoncarmel10 on Tuesday August 30, 2011 @08:02AM (#2941050)
JPEGmini does not apply any filters on the photo, no pre processing whatsoever. JPEGmini went through BT.500 certification, the result was that given 2 images 1. source 2. recompressed, the tester could not tell which is the source and which is the recompressed. Enjoy.
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Re:Impressive JPEG Recompression by CJefferson on Tuesday August 30, 2011 @10:23AM (#2941541)
I'm not sure what BT.500 certification is, but I can certainly tell the difference on some (not all) images, when recomposed.

Are you attached to JPEGmini? If so, would you be willing to bet that I cannot tell if a photo of my choice has gone through your system and been compressed?

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Re:Impressive JPEG Recompression by waitwhat on Tuesday August 30, 2011 @11:35AM (#2941874)
I'm on a 3G connection today, so relied on this thread for before/after images. Unfortunately, it seems that the original poster had labelled his photos the wrong way around...
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