darktable-org / darktable-org/darktable

TIFF/JPG snapshots are misaligned against raw file originals

Open
#16,357 16 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

no-issue-activity scope: UI
Dominant language
C
Stars
13.1k
Forks
1.4k
Avg merge
22h 14m
Merged PRs (30d)
198

Description

Describe the bug

When I export a raw file from DT into JPG or TIFF format and apply no changes, the snapshots are misaligned. The attached screenshot shows the issue.

Steps to reproduce
  1. Open a raw file
  2. Make no changes and export to JPG or TIFF format
  3. Import the exported file and create snapshot
  4. Return to the original raw file and activate snapshot. The two images will not line up one one another
Expected behavior

I'd expect the two images to lay on top of one another identically

Logfile | Screenshot | Screencast

Darktable screenshot anamoly

Commit

I just noticed this with version 4.7.0+339. My 4.6.0 version is corrupted so I wasn't able to determine if it applies there

Where did you obtain darktable from?

downloaded from www.darktable.org

darktable version

4.7.0+339~gf0f976dd7b

What OS are you using?

Windows

What is the version of your OS?

Window 11

Describe your system?

AMD Ryzen 5 5600X 6-Core Processor, 3701 Mhz, 6 Core(s), 12 Logical Processor(s)
NVIDIA GeForce RTX 3060
8 GB Ram

Are you using OpenCL GPU in darktable?

Yes

If yes, what is the GPU card and driver?

NVIDIA GeForce RTX 3060

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

The raw file is .CR3 format from a Canon R7, but the issue occurs with .CR2 files as well. Sometimes the misalignment can become quite severe.

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the issue with a CR3 or CR2 raw file on Windows: export it unchanged to JPG or TIFF, import the result, create a snapshot, and compare it with the original. Trace the export and snapshot comparison paths to identify the alignment discrepancy; done means the exported image and the raw-file snapshot overlay identically.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
computer-graphics
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Mostly clear
Newbie friendliness
45/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.