---
name: "gdal_sieve"
section: "1"
platform: "linux"
package: "gdal"
version: "3.13.3-6"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/gdal_sieve"
---

# gdal\_sieve(1)

Removes small raster polygons.

## NAME

gdal\_sieve - Removes small raster polygons.

## SYNOPSIS

```
gdal_sieve [--help] [--help-general]
              [-q] [-st threshold] [-4] [-8] [-o name=value]
              <srcfile> [-nomask] [-mask filename] [-of format] [<dstfile>]
```

## DESCRIPTION

**gdal\_sieve** removes raster polygons smaller than a provided threshold size (in pixels) and replaces them with the pixel value of the largest neighbour polygon. The result can be written back to the existing raster band, or copied into a new file.

The input dataset is read as integer data which means that floating point values are rounded to integers. Re-scaling source data may be necessary in some cases (e.g. 32-bit floating point data with min=0 and max=1).

Additional details on the algorithm are available in the *GDALSieveFilter()* docs.

**NOTE:**

gdal\_sieve is a Python utility, and is only available if GDAL Python bindings are available.

**TIP:**

Equivalent in new "gdal" command line interface:

See *gdal raster sieve*.

## RETURN STATUS CODE

The program returns status code 0 in case of success, and non-zero in case of error (non-blocking errors emitted as warnings are considered as a successful execution).

## AUTHOR

Frank Warmerdam \<warmerdam@pobox.com\>

## COPYRIGHT

1998-2026