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+--- Thread: ht set default compression level for png export? (/Thread-ht-set-default-compression-level-for-png-export)
ht set default compression level for png export? - ottenm - 01-31-2025
On the "Export Image as PNG" dialog, my compression level was set to 9, causing png exports to take over 60s. If I set it to 4, about 2s. Awesome, but the next time the dialog comes up: 9. Is there a way to set this permanently to 4? (either inside gimp, or somewhere out in config/options/settings files)
RE: ht set default compression level for png export? - programmer_ceds - 01-31-2025
(01-31-2025, 01:20 PM)ottenm Wrote: On the "Export Image as PNG" dialog, my compression level was set to 9, causing png exports to take over 60s. If I set it to 4, about 2s. Awesome, but the next time the dialog comes up: 9. Is there a way to set this permanently to 4? (either inside gimp, or somewhere out in config/options/settings files)If you are using V2.10.38 set the compression value that you want then click the "Save Defaults" button.
With V3.0.0 RC2 the last used values are presented when exporting a png - alternatively you can save and re-load settings - so V3.0.0.RC2 would do what you want.
RE: ht set default compression level for png export? - Tas_mania - 02-01-2025
PNG compression is set on a file by file basis.
[attachment=13034]
Does anyone know of a 'global' Gimp setting for the PNG compression value?
I use ofn-export-all-files and it uses the default compression of 9.
RE: ht set default compression level for png export? - Ofnuts - 02-01-2025
Did you try to export a PNG "manually", set the compression to 5, and hit Save defaults before hitting Export?
RE: ht set default compression level for png export? - Tas_mania - 02-01-2025
I investigated this.
First I found my ofn-export-layers was from 2018.
I upgraded to one from 2023 that has the pop-up 'Export Image as PNG'.
I found the PNG file size increased as I reduced 'compression level'.
I checked the built-in 'Export As...'
It did the same so I assume the ofn script uses the Gimp 'Export As'
The frames I used were jpg and about 800kb. By exporting as PNG they went up to 3.2Mb and as high as 4.2Mb.
I'm using Gimp 2.10.38 appimage that may have a bug in it.
RE: ht set default compression level for png export? - Ofnuts - 02-01-2025
(02-01-2025, 06:02 AM)Tas_mania Wrote: I investigated this.
First I found my ofn-export-layers was from 2018.
I upgraded to one from 2023 that has the pop-up 'Export Image as PNG'.
I found the PNG file size increased as I reduced 'compression level'.
I checked the built-in 'Export As...'
It did the same so I assume the ofn script uses the Gimp 'Export As'
The frames I used were jpg and about 800kb. By exporting as PNG they went up to 3.2Mb and as high as 4.2Mb.
I'm using Gimp 2.10.38 appimage that may have a bug in it.
Depending on content it is normal to find the PNG bigger than the JPG. In addition if you use high precision images (16-bit or more) the PNG is by default (automatic pixelformat) saved as a 16-bit PNG which doubles its size.
If you use the version with the dialog, the script uses the dialog values for all the layers.