Search found 43 matches

by WinnieW
Mon Aug 18, 2025 10:31 am
Forum: MP - General Support
Topic: WEBP
Replies: 3
Views: 118

Re: WEBP

I guess the WEBP developers use the same settings like JPEG,
set JPEG encoder to 100% quality means lossy compression, too.

The only difference is that WEBP has an additional lossless compression algorithm, which JPEG has not.

It might be confusing to users that a 100% setting doesn't mean ...
by WinnieW
Tue Aug 12, 2025 11:41 am
Forum: NConvert
Topic: XYB color space with JPEGLI ??
Replies: 7
Views: 773

Re: XYB color space with JPEGLI ??

A new release of libjxl is in the pipeline. It's just a matter of days.
This will also fix pending bugs in jpegli, incl. bugs related to XYB color space in jpegli.
by WinnieW
Tue Aug 12, 2025 11:14 am
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation

Wouldn't it be a better solution to ask the developers of JPEG XL how to modify the image orientation of existing JXL files instead of doing such a hackish approach?

Anybody is allowed to ask questions on the github plattform.

https://github.com/libjxl/libjxl/issues
by WinnieW
Mon Jul 07, 2025 10:09 am
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation


I was living under the impression that it is already finalized.

The format itself is finalized, but the encoder and decoder are still under development... JPEG XL is considered to be in a pre-release state, atm.
It's in a "use at your own risk" state of development. I would check every single ...
by WinnieW
Sun Jul 06, 2025 9:34 pm
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation

Wouldn't it be better to wait with mass conversations to JXL until the JPEG XL encoder is finalized?

Are you talking a developer into implementing a feature that is non-standard just to match your personal work flow?
by WinnieW
Sun Jul 06, 2025 8:06 pm
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation

There is one question that puzzles me. Why not encode the image with the desired orientation in first place?
Why all the hazzle with image orientation tags?

Why not rotate the image accordingly before encoding to JPEG XL?
by WinnieW
Sat Jul 05, 2025 7:26 pm
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation

Thats not a proper solution, golemus, imo. When it comes to interoperability with other software that handles JXL files as the standard demands.
Maybe ask a developer of JPEG XL where the orientation flag is located in the bitstream?
by WinnieW
Fri Jul 04, 2025 9:17 am
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation

Problem in this case: JPEG XL is free to use, however the JXL format specification is not for free.
by WinnieW
Wed Jul 02, 2025 5:17 pm
Forum: Closed/Resolved
Topic: JPEG XL Orientation
Replies: 26
Views: 3198

Re: JPEG XL Orientation

The JPEG XL format has its own flag for image orientation. libJXL ignores the image orientation information from the EXIF tag.

Source:
https://github.com/libjxl/libjxl/blob/f88745497118727f861cb00887cadcb395d10f1c/doc/format_overview.md
under section Metadata versus Image Data.

I don't know how ...
by WinnieW
Mon May 12, 2025 1:32 pm
Forum: NConvert
Topic: XYB color space with JPEGLI ??
Replies: 7
Views: 773

Re: XYB color space with JPEGLI ??

I noticed that.
Maybe the priority isn't high, or the developers assume that JPEG files with XYB are considered experimental and only a few people are using that coding option.
Anyway, in the meantime, until a proper bugfix is in the official code of jpegli,
a quick fix might be disabling color ...
by WinnieW
Thu May 08, 2025 1:47 pm
Forum: Classic - Suggestions
Topic: jpeg xl CMYK support...?
Replies: 2
Views: 330

Re: jpeg xl CMYK support...?

CMYK color space is primarily of interest for printing images. For displaying CMYK images on a monitor they have to be converted to RGB color space for that purpose.
by WinnieW
Thu May 01, 2025 10:01 am
Forum: MP - Suggestions
Topic: Better subsampling data
Replies: 3
Views: 355

Re: Better subsampling data


Are you sure that JXL (lossy) is always 444?
Raw 420 data consumes 60% of 444 data space. Seems akward if JXL didn't have opportunity to use this.

JPEG XL does use XYB color space by default. 420 subsampling is only defined for YUV color space.
Only legacy JPEG does use YUV color space by ...
by WinnieW
Wed Apr 30, 2025 9:24 am
Forum: NConvert
Topic: XYB color space with JPEGLI ??
Replies: 7
Views: 773

Re: XYB color space with JPEGLI ??

Ok, but there is a notice in the libjxl that further development of jpegli will happen in the jpegli repository.

https://github.com/libjxl/libjxl/blob/main/lib/jpegli/README.md

Maybe there will backport jpegli development to the libjxl repository.

Incorrect XYB subsampling in cjpegli hasn't ...
by WinnieW
Sun Apr 27, 2025 2:30 pm
Forum: NConvert
Topic: XYB color space with JPEGLI ??
Replies: 7
Views: 773

Re: XYB color space with JPEGLI ??

Important fix of JPEG with XYB color profile and subsampling is in git now. XYB color subsampling was incorrect in the past.

https://github.com/google/jpegli/pull/130
by WinnieW
Tue Feb 25, 2025 11:00 am
Forum: Closed/Resolved
Topic: Quality options for loading/decoding JPEG
Replies: 15
Views: 3621

Re: Quality options for loading/decoding JPEG

Yeah,
but the developers of jpegli claim their own jpeg decoder use floating point calculation and conversion to integer only once, so there are fewer rounding errors, which means possibly more accuracy.

https://github.com/google/jpegli#decoder-improvements

I compared decoding existing jpeg ...