2013-10-12

Kdenlive Effect: Protune

In my article Grading of Hero 3 (Above Waterline) Footage I've shown how to create a new effect template in Kdenlive for uncompressing the tonal curve of Protune raw footage. This effect is really useful for working with Hero 3 video footage.

You can also directly create the effect outside of Kdenlive without fiddling around with the curve handles...

Simply copy the following text into a text editor, such as KDE's Kate:
<effect version="0.2" tag="frei0r.curves" type="custom" LC_NUMERIC="C" id="Protune RGB" disable="0">
 <name>Protune RGB</name>
 <description>Color curves adjustment</description>
 <author>Till Theato, Maksim Golovkin</author>
 <parameter default="0,5" type="list" value="0,5" name="Channel" paramlist="0,5;0;0,1;0,2;0,3;0,4;0,6;0,71">
  <paramlistdisplay>RGB,Red,Green,Blue,Alpha,Luma,Hue,Saturation</paramlistdisplay>
  <name>Channel</name>
 </parameter>
 <parameter default="1" type="list" value="1" name="Luma formula" paramlist="0;1">
  <paramlistdisplay>Rec. 601,Rec. 709</paramlistdisplay>
  <name>Luma formula</name>
 </parameter>
 <parameter default="-1;-1#0;0#0,1;0,1|0,9;0,9#1;1#2;2" depends="Channel" type="bezier_spline" value="-1,414;-1,73159e-16#0;0#0,387;0|0,619;1#1;1#2,41421;1" name="Bézier spline"/>
 <version>0,3</version>
</effect>
Then save this content to a file that needs to be in the directory for Kdenlive custom effects: .kde/share/apps/kdenlive/effects/,for instance, use the file name Protune RGB.xml. You'll find the directory .kde directly under your home directory. If you can't see this directory in the file dialog or file manager, then please press ALT+. (ALT key and dot key simultaneously): this shows all files and directories starting with a dot, which otherwise may be hidden on purpose.

Custom Protune effect for Kdenlive.
You will need to restart Kdenlive in order to see your newly added custom effect. You'll find it listed under the effects category Custom with the name Protune RGB.

This Bézier curve applies to all three color channels red, green, and blue simultaneously. This is also reflected in the name of the custom effect. Of course, you can specify any other name you want; make sure to specify it between the <name>...</name> tags. The file name can be choosen arbitrarily more or less.