> For the complete documentation index, see [llms.txt](https://astra-image.gitbook.io/astra-image-6.0/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://astra-image.gitbook.io/astra-image-6.0/processing-tools/arithmetic-filter.md).

# Arithmetic Filter

The Arithmetic Filter will perform simple mathematical operations on the image.

<div align="left"><figure><img src="/files/p6P13u6FG934AHi1nG2f" alt="The Arithmetic Filter tool."><figcaption><p>The Arithmetic Filter tool.</p></figcaption></figure></div>

**Filter Type**\
This contains the types of operations than can be performed on the image. Minimum will replace the pixel with the minimum value in the window size. Maximum will replace the pixel with the maximum value in the window size. Median and mean will replace the pixel with the median or mean value in the window size.

**Filter window size**\
This is the size of the window (in pixels) to use in the calculation of the new pixel value.