Developer Reference

  • 2021
  • 03/26/2021
  • Public Content
Contents

Median Filters

The median filter functions perform non-linear filtering of a source image data.
These functions use either an arbitrary rectangular mask, or the following predefined masks of the
IppiMaskSize
type to filter an image:
ippMskSize3x1
Horizontal mask of length 3
ippMskSize5x1
Horizontal mask of length 5
ippMskSize1x3
Vertical mask of length 3
ippMskSize3x3
Square mask of size 3
ippMskSize1x5
Vertical mask of length 5
ippMskSize5x5
Square mask of size 5
The size of the neighborhood and coordinates of the anchor cell in the neighborhood depend on the
mask
mean value. Table
“Median Filter Mask, Neighborhood, and Anchor Cell”
lists the mask types with the corresponding neighborhood sizes and anchor cell coordinates. Mask size in mask names is indicated in (
XY
) order. The anchor cell is specified by its coordinates
anchor.x
and
anchor.y
in the coordinate system associated with the upper left corner of the mask.
Median Filter Mask, Neighborhood, and Anchor Cell
Mask
Neighborhood Size
Anchor Cell
Columns
Rows
ippMskSize3x1
3
1
[1, 0]
ippMskSize5x1
5
1
[2, 0]
ippMskSize1x3
1
3
[0, 1]
ippMskSize3x3
3
3
[1, 1]
ippMskSize1x5
1
5
[0, 2]
ippMskSize5x5
5
5
[2, 2]
Median filters have the effect of removing the isolated intensity spikes and can be used to reduce noise in an image.
For details on algorithms used in Intel IPP for median filtering, see [APMF].

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.