Method

VipsImageconvasep

Declaration [src]

int
vips_convasep (
  VipsImage* in,
  VipsImage** out,
  VipsImage* mask,
  ...
)

Description [src]

Optional arguments:

  • layers: %gint, number of layers for approximation

Approximate separable integer convolution. This is a low-level operation, see vips_convsep() for something more convenient.

The image is convolved twice: once with mask and then again with mask rotated by 90 degrees. mask must be 1xn or nx1 elements. Elements of mask are converted to integers before convolution.

Larger values for layers give more accurate results, but are slower. As layers approaches the mask radius, the accuracy will become close to exact convolution and the speed will drop to match. For many large masks, such as Gaussian, layers need be only 10% of this value and accuracy will still be good.

The output image always has the same VipsBandFormat as the input image.

See also: vips_convsep().

This method is not directly available to language bindings.

Parameters

out

Type: VipsImage

Output image.

The argument will be set by the function.
The caller of the method takes ownership of the returned data, and is responsible for freeing it.
mask

Type: VipsImage

Convolve with this mask.

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.