---
name: "im_lowpass"
section: "3"
platform: "linux"
package: "libvips-dev"
version: "7.20.7-1+b3"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/im_lowpass"
---

# im\_lowpass(3)

remove high frequencies quickly

## NAME

im\_lowpass - remove high frequencies quickly

## SYNOPSIS

\#include \<vips/vips.h\>

int im\_lowpass(in, out, x, y)\
 IMAGE \*in, \*out;\
 int x, y;

## DESCRIPTION

Expand image up to X by Y pixels. Linear interpolation. Used by lowpass(1X) for simple and nasty low-pass filtering. The result is very poor, but good enough for smoothing out whites. Any number of bands, output size == input size, any non-complex type.

## RETURN VALUE

The function returns 0 on success and -1 on error.

## SEE ALSO

[im\_shrink(3)](/im_shrink/3.md), [im\_similarity\_area(3)](/im_similarity_area/3.md).

## COPYRIGHT

National Gallery

## AUTHOR

Too embarrassed to say