Infinite loop when comparing with snaphot

[kofa73]

Is there an existing issue for this?

• I checked and did not find my issue in the already reported ones

Describe the bug

Comparing re-imported JPG with raw results in infinite processing loop. The UI is updated, but darktable keeps logging; 'working' may be seen on the screen. It is possible to end this by disabling the snapshot. Side-by-side or split display does not matter.

Steps to reproduce

1. Get the original JPG and the raw from https://discuss.pixls.us/t/old-edits-appear-darker-after-darktable-5-4-0-update/55324
2. Load the history stack from the JPG, applying it to the raw.
3. Load the JPG in the darkroom, create a snapshot
4. Switch to the raw.
5. Disable the composite module, we don't have the referenced image.
6. Enable comparison with JPG via the snapshot.
7. Observe the console.

Alternatively, try the attached XMP for the raw.

Expected behavior

No loop

Logfile | Screenshot | Screencast

The following messages are repeated:

   407.0539 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.0539 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.0539 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.0539 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.0540 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.0540 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.0540 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.0540 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.0566 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.814
   407.0566 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.0566 [dev_process_image] pixel pipeline took 0.003 secs (0.005 CPU) processing `_MG_4826.CR2'
   407.1383 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.1384 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.1384 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.1384 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.1384 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.1384 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.1384 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.1384 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.1406 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.815
   407.1406 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.1406 [dev_process_image] pixel pipeline took 0.002 secs (0.004 CPU) processing `_MG_4826.CR2'
   407.2195 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.2195 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.2195 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.2195 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.2195 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.2195 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.2196 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.2196 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.2217 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.816
   407.2217 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.2217 [dev_process_image] pixel pipeline took 0.002 secs (0.004 CPU) processing `_MG_4826.CR2'
   407.3373 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.3373 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.3373 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.3373 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.3373 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.3374 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.3374 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.3374 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.3394 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.817
   407.3394 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.3394 [dev_process_image] pixel pipeline took 0.002 secs (0.004 CPU) processing `_MG_4826.CR2'
   407.4202 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.4202 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.4202 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.4202 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.4202 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.4202 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.4203 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.4203 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.4231 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.818
   407.4231 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.4231 [dev_process_image] pixel pipeline took 0.003 secs (0.006 CPU) processing `_MG_4826.CR2'
   407.5129 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.5129 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.5129 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.5129 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.5130 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.5130 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.5130 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.5130 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.5150 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.819
   407.5151 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.5151 [dev_process_image] pixel pipeline took 0.002 secs (0.004 CPU) processing `_MG_4826.CR2'
   407.5947 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.5947 dev_pixelpipe_change          [full HQ]                                     zoomed, 
   407.5947 get dimensions                [full HQ]                                          (0/0)  5568x3708 sc=1.000; ID=19472
   407.5947 modified roi OUT              [full HQ]        rawprepare              100       (0/0)  5568x3708 sc=1.000 -->       (0/0)  5494x3666 sc=1.000; 
   407.5947 pipe cache check              [full HQ]                                     64 lines (important=1, used=13). Freed: invalid 0MB used 0MB. Using 1983MB, limit=2007MB
   407.5947 pipe starting             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472 using 43894MB
   407.5948 cache HIT                     [full HQ]        gamma                  12800  IOP_CS_RGB 2.219 1.000 1.423, hash=a4c2865e8538d9e1
   407.5948 pipe data: from cache         [full HQ]        gamma                  12800       (0/0)  2283x1524 sc=0.416; 
   407.5969 cache report                  [full HQ]                                     64 lines (important=1, used=13, invalid=0). Using 1983MB, limit=2007MB. Hits/run=0.99. Hits/test=0.820
   407.5969 pipe finished             CPU [full HQ]                                          (0/0)  2283x1524 sc=0.416; '_MG_4826.CR2' ID=19472
   407.5969 [dev_process_image] pixel pipeline took 0.002 secs (0.005 CPU) processing `_MG_4826.CR2'
   407.6764 [dt_dev_process_image_job] loading image. took 0.000 secs (0.000 CPU)
   407.6764 dev_pixelpipe_change          [full HQ]                                     zoomed, 

Sidecar:
_MG_4826.CR2.xmp.txt

Commit

No response

Where did you obtain darktable from?

self-compiled

darktable version

5.5.0+77~g161c75be3e

What OS are you using?

Linux

What is the version of your OS?

Ubuntu 25.10

Describe your system

No response

Are you using OpenCL GPU in darktable?

None

If yes, what is the GPU card and driver?

OpenCL on/off does not matter

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

No response

[TurboGit]

@kofa73 : I cannot reproduce.

[kofa73]

I cannot reproduce it with (edit!) master the release AppImage, even if using the same darktablerc as in my normal installation, but if I run my locally built 5.5.0+77~g161c75be3e, I get the issue.
The best way I have been able to find: enable the color assessment frame. Have darktable full-screen on a 4K display. Use Alt+tab to toggle between darktable and the terminal.
For now, it's not infinite (with a new config dir, only these 2 images in the DB, using the XMP I shared above, removing darktablerc before starting dt), but longer than it should be.

2026-01-09_19-03-28.mp4