darktable-org / darktable-org/rawspeed
"zero_is_not_bad" hint implemented for RW2, never active
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- Dominant language
- C++
- Stars
- 456
- Forks
- 147
- PR merge metrics
- No merged PRs in 30d
Description
On my local darktable installation
/usr/share/darktable/rawspeed$ grep "Hint " * | sort
shows that none of the cameras defined in cameras.xml implements the hint "zero_is_not_bad".
In rawspeed implementation, zero_is_not_bad is only used in the context of RW2 processing. It is always used in such a fashion that zero_is_bad = !zero_is_not_bad.
This implies that for all RW2 formats, zero_is_bad == true, always.
Why is there implementation for such an implied metadata hint if there is nothing that exploits that hint?
Given the current implementation, it would appear to be
- safe (and prudent) to remove handling of the unused zero_is_not_bad metadata hint
- necessary (still) to review how exactly to handle zero values in raw data in the V5 format
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by inspecting cameras.xml and the RW2 processing implementation where zero_is_not_bad is read. Confirm whether any camera uses the hint, then review the V5 zero-value behavior before deciding whether the unused metadata handling can be removed. Done means the hint's status and V5 zero semantics are addressed with appropriate validation.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- computer-graphics
- Issue type
- Refactor
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 28/100