The Pixelize filter renders the image using large color blocks. It is very similar to the effect seen on television when obscuring a criminal during trial. It is used for the “Abraham Lincoln effect”: see [BACH04].
Here you can set the desired width and height of the blocks.
By default, width and height are linked, indicated by the chain symbol next to the input boxes. If you want to set width and height separately, click on that chain symbol to unlink them.
Using the unit selection box you can select the unit of measure for height and width.