2.10.36, 2.99.18 - GIMP does not import/export non-standard PNG tEXt chunks
Environment/Versions
- GIMP version: 2.10.36 AND 2.99.18
- Package: Installer from gimp.org
- Operating System: Windows 11
Description of the bug
When importing a PNG file (a.png), then exporting it (b.png), the metadata in a.png is missing from b.png
Reproduction
Is the bug reproducible? Always
Reproduction steps:
- Ensure all metadata export options are enabled in "Preferences" > "Image Import & Export"
- Import a PNG file with metadata (such as one produced by StableDiffusion sd.webui, which will contain generation parameters).
- Observe the metadata in the imported PNG in "Image" > "Metadata" > "View Metadata"
- Export the PNG file, ensure all metadata export options are enabled in "Export Image as PNG".
- Compare the metadata of the original and exported PNG files. (This can be done by opening the PNG files in a text editor.)
Expected result:
- After importing, the metadata contained in the original PNG file is visible in "Image" > "Metadata" > "View Metadata"
- The metadata found in the original PNG file is contained in the exported PNG file.
Actual result:
- After importing, the metadata contained in the original PNG file is MISSING from "Image" > "Metadata" > "View Metadata"
- The metadata found in the original PNG file is ABSENT from the exported PNG file; the exported PNG file contains useless metadata.
Additional information
This is important for certain plugins used by sd.webui.
Edited by Stephen Smolley