GNOME Video Effects is a collection of GStreamer effects that can be used in GNOME applications. It is currently used by Cheese, meaning it has all those nice effects that are used in Cheese.

Effects are described in a very simple format, so it’s very easy to add a new effect if you know a little about GStreamer. The famous hulk effect is as simple as:

[Effect]
Encoding=UTF-8
Name=Hulk
Name[pt_BR]=Hulk
Comment=Transform yourself into the amazing Hulk
Comment[pt_BR]=Transforme-se no incrível Hulk
PipelineDescription=videobalance saturation=1.5 hue=-0.5

It couldn’t be simpler, but it doesn’t allow us to change anything. In many effects, it would be nice to have configurable properties, such as making hulk more or less green or choosing delaying time in timedelay for 2 or for 20 seconds. This would allow other applications to use GNOME Video Effects as well.

The new format to specify configurable properties is being discussed in bug number 626533. We are heading to something like this, with some details to be decided:

[Effect]
Encoding=UTF-8
Name=Hulk
Name[pt_BR]=Hulk
Comment=Transform yourself into the amazing Hulk
Comment[pt_BR]=Transforme-se no incrível Hulk
PipelineDescription=videobalance saturation=1.5 hue=-0.5 name=balance1

[Property::angriness]
Name=Angriness
Name[pt_BR]=Raiva
Comment=Change the angriness of Hulk by making yourself more or less green.
Comment[pt_BR]=Mude a raiva do Hulk ficando mais verde ou menos verde.
Type=double
Min=1.2
Max=1.6
Element=balance1
Property=saturation

Currently, GNOME Video Effects only provides a collection of effects, but parsing should be done by the application using it. As this format will be a little more complicated, I’m also thinking about writing a library that could be used by the applications and, off course, use it in Cheese.