[v26] incorrect lossless encoding

[Kadet]

On XnPC, converting jpg to png gives the same CRC in pixel-level file comparison (Shift-C). The same file converted to png on XnMOBI gives a different CRC. After enlarging it, I can't visually notice the difference, but there must be a difference since there is a different CRC.

[xnview]

Please send me the original file and the one converted by XnView & XnMobile?

[Kadet]

Please send me the original file and the one converted by XnView & XnMobile?

https://drive.google.com/file/d/1ahUyaS ... sp=sharing

[xnview]

i've check on XnView, and the CRC is different between original.jpg & xnview.png

[Kadet]

Hmm. It's my:

XnView CRC Screen-2026-08-05_14-52-03.jpg

I set read the JPG files method as Floating-point (if it makes any difference).

In my opinion, this is the right behavior to keep the CRC the same. Of course, it is true if the same JPG decoding method is used to covert and to compare.

[Kadet]

I set read the JPG files method as Floating-point (if it makes any difference).

When I changed this setting now I have different CRC in compared function XnView on Windows.

This seems to explain everything. One method should be used to read (and encode?) JPG files. For me it should be Floating-point. Nowadays computers are so fast that others don't matter.

[xnview]

ok, now i understand. I've added settings for JPEG
Please check v28

[Kadet]

I set JPG reading to FP, but the CRC still does not match. It does not match any DCT reading method in XnPC at all.

[xnview]

I set JPG reading to FP, but the CRC still does not match. It does not match any DCT reading method in XnPC at all.

After some search, on ARM you can't get same CRC using 'float' as intel x64.