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JPEG Quality Issue
#8
(06-30-2024, 04:51 PM)Ofnuts Wrote: JpegLi isn't a new format (otherwise Gimp wouldn't read it without additional plugins), but a new library implementation, published by Google in April 2024 (so, fairly recent...)

If you look at the number of colors, it is easy to guess how they achieve the result:
  • Q90 image: 39600
  • Q5 image: 2077
  • JpegLI Q20 image: 7753
  • JpegLI Q5 image: 1655
The image RGB histograms are also quite telling. Additionally, ImageMagick's identify can't find a quality setting in the JpegLi files).

So JPegLi is perhaps better at finding colors that mitigate the blocky look, but if you want to keep some image quality, you have better stick to good quality settings where it is not going to be much better than the "classic" library. And don't mistake the intent: Google has been in a crusade to reduce the internet bandwidth usage and has in the past provided many tools to reduce image size. But this is for distribution/publication, not archival nor editing...
I use the cjpegli.exe file included with the jxl format implementation reference library 
(https://github.com/libjxl/libjxl/releases/ v0.10.2 08-03-2024r)
Google did not influence me.

After all, when processing a photo, I save as Q100, and only then use the XL Converter program.
What was the point of lossy re-encoding.
I believe that
We should like the results more by eye, which are more important than the various indicators.
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Messages In This Thread
JPEG Quality Issue - by d0m1n1k - 06-29-2024, 08:50 AM
RE: JPEG Quality Issue - by Ofnuts - 06-29-2024, 04:21 PM
RE: JPEG Quality Issue - by d0m1n1k - 06-29-2024, 06:20 PM
RE: JPEG Quality Issue - by Ofnuts - 06-29-2024, 09:48 PM
RE: JPEG Quality Issue - by Zbyma72age - 06-30-2024, 03:29 PM
RE: JPEG Quality Issue - by d0m1n1k - 06-30-2024, 12:26 PM
RE: JPEG Quality Issue - by Ofnuts - 06-30-2024, 04:51 PM
RE: JPEG Quality Issue - by Zbyma72age - 06-30-2024, 05:41 PM
RE: JPEG Quality Issue - by Ofnuts - 06-30-2024, 09:52 PM

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