!! Bug 2 Error !! Invalid Chroma Sampling

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jxl
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Joined: Fri Oct 08, 2021 1:05 am

!! Bug 2 Error !! Invalid Chroma Sampling

Post by jxl »

In the AVIF format. 444 422 420. The file size after the conversion is same. The converted MD5 is same. The picture used to test is 444 png.
AVIF.png
Thanks!

jpeg XL also has an error.
quality below 9. Bytes will be larger. You can test with 012345678 quality levels. They are all much larger than 9.
JXL.png
There's something wrong with my post. The contents of the first floor disappeared. Now I edit it again. Please re-read my edited post. Thank you very much for noticing my problem. Dear developer.
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Last edited by jxl on Fri Oct 08, 2021 2:03 pm, edited 3 times in total.
github.com/GoogleChromeLabs/squoosh
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xnview
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Re: !! Bug 2 Error !! Invalid Chroma Sampling

Post by xnview »

what do you means? Compression (effort) with 0 will create larger file
Pierre.
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jxl
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Re: !! Bug 2 Error !! Invalid Chroma Sampling

Post by jxl »

xnview wrote: Fri Oct 08, 2021 9:04 am what do you means? Compression (effort) with 0 will create larger file
I mean: in jpeg XL. Set the quality to 9. Get the smallest file at this point. Set the quality to 8. Get a larger file at this point. Much larger than 9. The quality 0 to 8 file sizes are the same. file MD5 is the same for 0 to 8.

Another problem for me: in AVIF. Chromose sampling is an invalid setting. Whether set to 4:4:4 or 4:2:2 or 4:2:0. You will get files of the same size. The MD5 of the three result files is the same. Normal behavior is: 4:2:0 is smaller than 4:4:4 file.
github.com/GoogleChromeLabs/squoosh
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xnview
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Re: !! Bug 2 Error !! Invalid Chroma Sampling

Post by xnview »

jxl wrote: Fri Oct 08, 2021 1:35 pm
xnview wrote: Fri Oct 08, 2021 9:04 am what do you means? Compression (effort) with 0 will create larger file
I mean: in jpeg XL. Set the quality to 9. Get the smallest file at this point. Set the quality to 8. Get a larger file at this point. Much larger than 9. The quality 0 to 8 file sizes are the same. file MD5 is the same for 0 to 8.
I've tried and can't reproduce, same with cjxl? which image file do you use?
Pierre.