Vips.Image.labelregions (original) (raw)

Method

VipsImagelabelregions

Declaration [src]


int
vips_labelregions (
  VipsImage* in,
  VipsImage** mask,
  ...
)

Description [src]

Label regions of equal pixels in an image.

Repeatedly scans in for regions of 4-connected pixels with the same pixel value. Every time a region is discovered, those pixels are marked in mask with a unique serial number. Once all pixels have been labelled, the operation returns, setting segments to the number of discrete regions which were detected.

mask is always a 1-band VIPS_FORMAT_INT image of the same dimensions as in.

This operation is useful for, for example, blob counting. You can use the morphological operators to detect and isolate a series of objects, then usevips_labelregions() to number them all.

Use vips_hist_find_indexed() to (for example) find blob coordinates.

Optional arguments

This method is not directly available to language bindings.

Parameters

mask

Type: VipsImage

Write labelled regions here.

The data is owned by the caller of the method.

...

Type: ``

NULL-terminated list of optional named arguments.

Return value

Type: int

0 on success, -1 on error.