JPEG XL .DNG not supported

[nghiatranol]

Describe the bug

We have tried to open the DNG file (which is the input.dng in the zip) in darktable without any success, the error just said that darktable cannot load the file

input.zip

Steps to reproduce

1. Open darktable desktop app
2. Click on 'add to library'
3. Choose the file input.dng
4. Click on 'add to library' in the popup
   ---> the error message shows up

Expected behavior

darktable should be able to open the file

Logfile | Screenshot | Screencast

this is the log file from https://www.darktable.org/about/faq/#:~:text=Windows%2010%3A%20C%3A%5CUsers%5C%5Busername%5D%5CAppData%5CLocal%5CMicrosoft%5CWindows%5CINetCache%5Cdarktable%5Cdarktable%2Dlog.txt

darktable-log.txt

Commit

No response

Where did you obtain darktable from?

downloaded from www.darktable.org

darktable version

4.6.1

What OS are you using?

Windows

What is the version of your OS?

windows 11 pro

Describe your system?

No response

Are you using OpenCL GPU in darktable?

None

If yes, what is the GPU card and driver?

No response

Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip

No response

[ralfbrown]

A quick look shows the file to have been generated by Lightroom. RawSpeed complains that it can't find any RAW chunks (since LR generated it, it's probably demosaiced), and ImageMagick complains that it can't handle floating-point samples. You probably need to adjust the export settings in LR.

[pehar1]

And the file contains lots of doubled tags, some of them inconsistent, see for example "Bits Per Sample" from the extract of the exif data :

...
[EXIF]          0x0102 Bits Per Sample                 : 8 8 8                                                 
[EXIF]          0x0103 Compression                     : JPEG                                                  
[EXIF]          0x0106 Photometric Interpretation      : YCbCr                                                 
[EXIF]          0x010f Make                            : SONY                                                  
[EXIF]          0x0110 Camera Model Name               : ILCE-7M4                                              
[EXIF]          0x0111 Preview Image Start             : 140700                                                
[EXIF]          0x0112 Orientation                     : Horizontal (normal)                                   
[EXIF]          0x0115 Samples Per Pixel               : 3                                                     
[EXIF]          0x0116 Rows Per Strip                  : 171                                                   
[EXIF]          0x0117 Preview Image Length            : 9168                                                  
[EXIF]          0x011c Planar Configuration            : Chunky                                                
[EXIF]          0x0131 Software                        : Adobe Photoshop Lightroom Classic 13.1 (Macintosh)    
[EXIF]          0x0132 Modify Date                     : 2024:03:05 08:59:35                                   
[EXIF]          0x00fe Subfile Type                    : Full-resolution image                                 
[EXIF]          0x0100 Image Width                     : 7008                                                  
[EXIF]          0x0101 Image Height                    : 4672                                                  
[EXIF]          0x0102 Bits Per Sample                 : 16 16 16
...

The sample format is

[EXIF] 0x0153 Sample Format : Float; Float; Float

which is not supported by ImageMagick (error message from your log file)

Magick: Sorry, can not handle images with IEEE floating-point samples. ().

[kmilos]

Float DNGs are in principle supported*, and this shouldn't end up w/ the GraphicsMagick/ImageMagick loader anyway, something else fails earlier. I'll check...

*Is this a from a very recent Lightroom? Latest DNG 1.7 w/ JPEG XL compression is not yet supported.

[kmilos]

Yep:

SubfileType                     : Full-resolution image
ImageWidth                      : 7008
ImageHeight                     : 4672
BitsPerSample                   : 16 16 16
Compression                     : JPEG XL
PhotometricInterpretation       : Linear Raw

P.S. @pehar1 There are multiple IFDs (subimages like thumbnails and main image), and each has its own tags so there is no wonder you see them as "duplicated". In exiftool you need to use -g1 or -G1 to group them by IFD.

[kmilos]

@nghiatranol Please upload a sample to https://raw.pixls.us/ @LebedevRI

In the meantime, try exporting w/ DNG 1.6 (or earlier) compatibility.

Tracked by darktable-org/rawspeed#516

[LebedevRI]

I've verified some sample that claimed to be an JXL DNG, so that's nice, thank you!
(i really need to redesign the admin for RPU...)

Is there a library that supports that compression?
If someone wants, it should be relatively rather straight-forward to implement,
just follow what is done for jpeg and deflate...

[kmilos]

Is there a library that supports that compression?

Yes, listed a couple of options in the RawSpeed tracking issue.

[kmilos]

I've verified some sample that claimed to be an JXL DNG

Hm, the one I see listed on RPU ("Canon - EOS 7D Mark II - 16bit (3:2).dng") does claim it is DNG 1.7, but it is not JPEG XL compressed?