Compiz Plugins



First appeared in Compiz 0.4

The Blur Windows plugin uses pixel shaders to blur the screen area behind translucent (regions of) windows, and also to blur the windows themselves. Its extensible interface allows for future shaders to be added.

<!> Due to bugs in certain problematic video drivers, both blur modes are disabled by default in order to prevent Compiz from recursively crashing and/or starting in software rendering mode.

Note that Blur will fail to function in AiGLX on non-NVIDIA hardware and on all rendering modes on Intel hardware. This is due to a limitation in the drivers.

Using Blur

The three types of blur effects -- alpha blur, focus blur and pulse effect -- use the same blur filter, as defined in the Blur Filter settings.

Alpha Blur

Alpha Blur blurs the screen area behind wholly translucent windows, or, in the case of alpha-transparent windows, it blurs the area behind the translucent regions. In order for windows to have this effect applied to them, they must be specified in the Alpha blur windows window matching rule (see WindowMatching on how to do that).

Focus Blur

Focus Blur applies a blur effect to the windows specified in the Focus blur windows matching rule when they are inactive. This has the overall effect of making inactive windows blurry, while the focused window remains unblurred.

Pulse Effect

This is enabled via the Pulse option. The pulse effect will momentarily blur the focused window when the system bell is triggered. This serves as a visual bell effect.

Blur Filters


This filter is used by-default for focus blur and alpha blur. Because of it's static nature, it cannot be configured

4xBilleniar Blur shader.


This filter can be used only if supported by the hardware. It requires the use of Framebuffer Objects (Sometimes known as FBO's). This filter can be configured, but cannot be used for focus blur.

Gaussian Blur shader.

Gaussian Radius

The higher the pixel radius the blur shader should re-arrange to blur. The higher this number, the more 'spread out' the blur will be

Gaussian Strengh

How much to sharpen the image after blurring. Having this at a low level will cause the image to be blurred too much


This filter uses the built in mimap filtering of openGL to blur images. Note that even though it is fast, it can produce bad-looking pixelly images. Use with care. It requires direct rendering.

Mipmap Blur shader.

Mipmap LOD

The amount of blur to apply

General Configuration

  • Blur Speed : How fast to blur in and out windows when using Focus Blur

  • Blur Saturation : How much to desaturate the blurred image

  • Blur Occlusion : Whether or not to blur areas that can't be seen because they are blocked by other windows. This saves on memory and processing power, however it should be used with care as it will produce strange results when used in combination with other plugins such as the 3D Window Plugin.

  • Independent Texture fetch : Use more memory and processing power to be more efficient in fetching textures to blur.