Re:Impressive JPEG Recompression
by est on Tuesday August 30, 2011 @05:21AM
(#2940679)
Looks like the compressed version is a bit sharper to me.
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Sorry, I pasted the links in the wrong order. The original is this one: http://postimage.org/image/14712qgjo/ and the compressed image: http://postimage.org/image/94ol50ck/
File size was reduced from 4.4mb to 1.2mb
If the compressed version is apparently sharper than the original file, that's an artifact surely? It might be pleasing in some contexts but it's not an accurate representation of the original file in that aspect.
I mean, vytis claimed that
> The resulting image has way less detail in higher frequencies.
But the compressed version actually exposes more detail.
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.
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.
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?
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...