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Published 20 hours ago • verified publisher icon google

Color of JPG changes significantly

Open raphaelschaad opened this issue 7 years ago • 3 comments

The file size compression worked well and I don't see any artifacts but the colors changed "significantly" (for the field of photography) in all three examples I tested. One is attached (original and Guetzli-compressed -- best seen when downloaded and switched back and forth in place). All Guetzi-compressed ones seemed more red. What is the reason for that and can color somehow be preserved?

PS: As I was opening both images in Chrome browser tabs and switching back and forth, I didn't notice the red-shift. I suspect the experienced difference might stem from the way I previewed the files (e.g. using macOS quick look)?

Photo by VisibleCommunities.mit.edu / CC BY 4.0

Original: dsc00096

Guetzli-compressed: dsc00096-guetzli

raphaelschaad avatar Mar 26 '17 03:03 raphaelschaad

Awesome work guy.

On Mar 25, 2017 9:23 PM, "Raphael Schaad" [email protected] wrote:

The file size compression worked well and I don't see any artifacts but the colors changed "significantly" (for the field of photography) in all three examples I tested. One is attached (original and Guetzli-compressed -- best seen when downloaded and switched back and forth in place). All Guetzi-compressed ones seemed more red. What is the reason for that and can color somehow be preserved?

Photo by VisibleCommunities.mit.edu / CC BY 4.0

Original: [image: dsc00096] https://cloud.githubusercontent.com/assets/439447/24328215/abf01890-11b1-11e7-85f6-290077cd5a61.jpg

Guetzli-compressed: [image: dsc00096] https://cloud.githubusercontent.com/assets/439447/24328220/bc1ef34e-11b1-11e7-9d13-a8fe026094a6.jpg

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thehelp1 avatar Mar 26 '17 03:03 thehelp1

Same problem Original (it's too big for github): https://goo.gl/QiJwDY Guetzli-compressed: oute Most likely Guetzli has problems with the gamma of the image

brualan avatar Mar 26 '17 07:03 brualan

Hi there. Can confirm. Right side is the original file, left file the compressed one with quality 100.

Using version 1.0.1-3 from the AUR repository

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