Bug 437706

Summary: Cannot open GIMP XCF files especially when color depth is higher than 8 bits
Product: [Frameworks and Libraries] frameworks-kimageformats Reporter: Syv <digikam>
Component: generalAssignee: Alex Merry <alex.merry>
Status: RESOLVED WORKSFORME    
Severity: normal CC: aacid, caulier.gilles, dnovomesky, kdelibs-bugs, martin.sandsmark, mircomir, nate
Priority: NOR    
Version: 5.82.0   
Target Milestone: ---   
Platform: Other   
OS: Other   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Syv 2021-05-26 17:25:49 UTC 
SUMMARY
Cannot open GIMP XCF files especially when color depth is higher than 8 bits

as described by Gilles Caulier from Digikam

STEPS TO REPRODUCE
1. Open the following gimp image from Digikam

I cannot attach the file since it much larger than 4mb. Here's the link

https://www.sritch.com/pages/cares-20170212-6640.xcf  (96Mb)

OBSERVED RESULT (quote from Gilles Caulier)

..........................
Hi,

Yes problem is fully reproducible here. the Unit test from digiKam trying
to load image report a message from the KImageIO XCF plugin as file is not
recognized :

digikam.dimg: "cares-20170212-6640.xcf" : "QIMAGE" file identified
digikam.dimg.qimage: Can not load " "cares-20170212-6640.xcf" " using DImg::DImgQImageLoader!
digikam.dimg.qimage: Error message from loader: "Unable to read image data"                              <=====!!!!!!!
digikam.dimg: "cares-20170212-6640.xcf" : Unknown image format !!!

This is a problem in the KDE plugin. The problem is the same for both
shared files.

Note  that Exiftool is able to load XCF metadata :

[gilles@localhost dimg]$ exiftool  cares-20170212-6640.xcf
ExifTool Version Number         : 12.00
File Name                       : cares-20170212-6640.xcf
Directory                       : .
File Size                       : 98 MB
File Modification Date/Time     : 2021:05:26 05:13:00+02:00
File Access Date/Time           : 2021:05:26 05:37:17+02:00
File Inode Change Date/Time     : 2021:05:26 05:37:05+02:00
File Permissions                : rw-r--r--
File Type                       : XCF
File Type Extension             : xcf
MIME Type                       : image/x-xcf
XCF Version                     : 12
Image Width                     : 4781
Image Height                    : 3586
Color Mode                      : RGB Color
Compression                     : RLE Encoding
X Resolution                    : 300
Y Resolution                    : 300
Tattoo                          : 2
Units                           : Inches
Metadata Tag Name               : Exif.Canon.0x0003
Metadata Tag                    : 0 0 0 0
Comment                         :
Image Size                      : 4781x3586
Megapixels                      : 17.1

So, please report this problem to KDE bugzilla component
"frameworks-kimageformats". Look like there are already some files open
about XCF support, and especially when color depth is higher than 8 bits.

https://bugs.kde.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=CONFIRMED&bug_status=ASSIGNED&bug_status=REOPENED&component=general&list_id=1874818&product=frameworks-kimageformats&query_format=advanced

Best

Gilles Caulier
.........................

SOFTWARE/OS VERSIONS
OS: Manjaro Linux x86_64 
Host: MS-7693 2.0 
Kernel: 5.10.36-2-MANJARO 
Uptime: 3 hours, 13 mins 
Packages: 1542 (pacman) 
Shell: bash 5.1.8 
Resolution: 2560x1080 
DE: Plasma 5.21.5 
WM: KWin 
WM Theme: Breeze 
Theme: Breath2 [Plasma], Breeze [GTK2/3] 
Icons: breath2 [Plasma], breath2 [GTK2/3] 
Terminal: konsole 
Terminal Font: Noto Mono 14 
CPU: AMD FX-8350 (8) @ 4.000GHz 
GPU: AMD ATI Radeon RX 470/480/570/570X/580/580X/590 
Memory: 1037MiB / 11992MiB 

Qt 5.15.2 (x86_64-little_endian-lp64 shared (dynamic) release build; by GCC 10.2.0) on "xcb" 
OS: Manjaro Linux [linux version 5.10.36-2-MANJARO]

Architecture: x86_64; features: SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 AVX

Thank you
Comment 1 Albert Astals Cid 2021-05-26 21:42:52 UTC 
That file has two features we don't support:
 * It identifies itself as version 12 and we fail if version > 11
 * It has a layer of type RGB_GIMAGE with bpp 6 and we only support RGB_GIMAGE layers of bpp3

I stopped debugging there, needs someone to put some time into it.

Martin you did the last big-ish refactor in the XCF loader, fancy having a go?

Or maybe you Daniel?
Comment 2 Albert Astals Cid 2021-05-26 22:00:07 UTC 
FWIW https://gitlab.gnome.org/GNOME/gimp/-/blob/master/devel-docs/xcf.txt has a relatively good description of the format
Comment 3 dnovomesky 2021-05-27 10:10:20 UTC 
There are more things to do.

I tried to save some XCF files from development GIMP 2.99.7
When option "Save this XCF file with better but slower compression" is selected, kimg_xcf will not load it.

We should also load color profile and set it to QImage via QColorSpace class.
Comment 4 caulier.gilles 2022-07-06 11:34:22 UTC 
Hi,

I just checked with digiKam 7.8.0 using KF5 5.95, and a XCF file saved with 16 bits as integer do not render a thumbnail in icon view.

Best

Gilles Caulier
Comment 5 Mirco Miranda 2024-10-02 19:30:03 UTC 
(In reply to caulier.gilles from comment #4)
> I just checked with digiKam 7.8.0 using KF5 5.95, and a XCF file saved with
> 16 bits as integer do not render a thumbnail in icon view.

With the 2013 patches (https://invent.kde.org/frameworks/kimageformats/-/merge_requests/171) the plugin is able to render images with color depth greater than 8 bits.

Unfortunately the "attached" image is no longer accessible. Does it work now?
Comment 6 Bug Janitor Service 2024-10-17 03:47:52 UTC 
🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 7 Bug Janitor Service 2024-11-01 03:47:15 UTC 
🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.