G’MIC
Use filters for image and video editing
Nick Peers reveals how the G’MIC plugin can transform the way you repair and enhance both photographs and videos.
OUR EXPERT
Nick Peers has hundreds of old family history photos he needs to tidy up. G’MIC might be the plugin to help him achieve his goal.
When it comes to image and video editing, there’s nothing like applying a filter. Filters enable you to perform all kinds of digital processing – from simple corrections and fixes to transformative special effects – on your movies and photos, and you’ll find most video and image editors come with a selection built-in.
G’MIC – or GREYC’s Magic for Image Computing – is an open-source framework providing tools for creating such filters. Thanks to the efforts of dozens of volunteers, the G’MIC language has been used to develop hundreds of filters for both images and video, and its collections are expanding all the time.
G’MIC can be used several different ways. You can install it as a standalone tool to run from the shell – in this guise it’s effectively an interpreter for running the G’MIC language. But it’s also available as a QT-based plugin, which makes it possible to incorporate over 500 different filters into GIMP and Krita, which will be the main focus of this tutorial. We’ll also reveal how you can use G’MIC filters to transform video clips using the open-source Flowblade tool.
EXPLORING G’MIC-QT
1 Smart preview
Use this to see what effect your chosen filter will have on your image. Use the Preview tick box to toggle before and after views.
2 Settings
Click this button to customise the plugin’s interface, as well as configure automatic updates and output messages.
3 Filter list
Either browse filters by category or use the Search tool to find one quickly. Select a filter to preview and use it.
4 Bookmark filters
Use the add, remove and rename buttons to put together a collection of favourite filters for speedy access.
5 Filter controls
Use this section in conjunction with the real-time preview to fine-tune the filter’s effects using the options provided.
6 Input/Output
Use this option to set which part of the image is affected by the filter, and how the effect will be applied.
Support for G’MIC is built into both GIMP and Krita – no need to download or install anything. That’s the theory, at any rate. The problem is that both GIMP and Krita don’t ship with the latest version of G’MIC, and while that’s not necessarily a problem for Krita (the version of the plugin shipped with the latest 5.x release – 3.0.0 – works fine), you’ll find that if you install GIMP via snap, you’ll be stuck with a plugin – 2.9.6 – that throws up multiple errors with the smart preview on various filters.