Saturday 16 March 2019

Gimp resource usage challenges

Whilst Gimp has been great for the NZ Rail Maps mosaics, one of its challenges has been with the layer group feature. This feature unfortunately does a lot more than just organise layers in the layer list. Apparently it adds extra stuff that you may not need.

From my experience I have found the layer groups add significant resource usage, adding in the case of a particular project that was 16 GB, adding about 3 GB of file size for no apparent reason, and when doing a layer crop and export, massively increasing the time to do the crop, export and uncrop. The file save operations from experience have also been very slow.

I now use layer groups only to perform very basic operations, mainly for the grids for layer segmenting, which is only because I can duplicate the grids layers with one click, since you can't select multiple layers for duplicating but you can select a layer group and duplicate that.

It is a great pity as some of these mosaic projects have dozens of layers and I just have to put up with scrolling through a massive layer list to get to the ones I want, but it seems whatever Gimp is trying to achieve was not designed with the intention of allowing a simple reorganisation of the layers in a project with a large number of them.