06-19-2025, 07:15 AM
For Gimp, you can only "Save" in XCF. A JPG/PNG will not save everything in an image (layer structure, elections, paths...). So all these file types that don't save all the Gimp data are "Export"s (in your favorite word processor, you "save" to DOCX/ODT, and "export" to PDF...).
The default behavior is to save with the initial image quality. If you export a hitherto non-Jeg image, and change the quality from the defautl value, this setting is reused for all subsequent non-Jpeg images.
Saving images with 50% quality is a bad idea. This is a Q90 image resaved at Q50:
Disk space is cheap. Keep your images at Q80 or higher. It is easy to degrade the quality, it is impossible to restore it later. If you are tight on disk space, it could be a "less bad" idea to scale down the images to a size that is sill useful (say, 2400px) and export at decent quality. And before you lower the quality, make sure you are using the quartered chroma-subsampling, this reduces the file size significantly without impacting the image quality as much.
Also, the fact that you don't mention PNG is disturbing because PNG is the format of choice for about all non-photo images (often smaller than JPEG, without any artifacts)? GIF is pretty much relegated to low-quality animations the days.
Last, there is no "macro" in Gimp. You can write scripts, but this another skill level. There are plugins to perform actions in batcj modes on images, and many non-Gimp utilities that will transform an set of images (from memory XNView, IrfanView...).
The default behavior is to save with the initial image quality. If you export a hitherto non-Jeg image, and change the quality from the defautl value, this setting is reused for all subsequent non-Jpeg images.
Saving images with 50% quality is a bad idea. This is a Q90 image resaved at Q50:
Disk space is cheap. Keep your images at Q80 or higher. It is easy to degrade the quality, it is impossible to restore it later. If you are tight on disk space, it could be a "less bad" idea to scale down the images to a size that is sill useful (say, 2400px) and export at decent quality. And before you lower the quality, make sure you are using the quartered chroma-subsampling, this reduces the file size significantly without impacting the image quality as much.
Also, the fact that you don't mention PNG is disturbing because PNG is the format of choice for about all non-photo images (often smaller than JPEG, without any artifacts)? GIF is pretty much relegated to low-quality animations the days.
Last, there is no "macro" in Gimp. You can write scripts, but this another skill level. There are plugins to perform actions in batcj modes on images, and many non-Gimp utilities that will transform an set of images (from memory XNView, IrfanView...).