Method

VipsImagereducev

Declaration [src] 

int
vips_reducev (
  VipsImage* in,
  VipsImage** out,
  double vshrink,
  ...
)

Description [src]

Reduce in vertically by a float factor.

The pixels in out are interpolated with a 1D mask generated by kernel.

Set gap to speed up reducing by having vips_shrinkv() to shrink with a box filter first. The bigger gap, the closer the result to the fair resampling. The smaller gap, the faster resizing. The default value is 0.0 (no optimization).

This is a very low-level operation: see vips_resize() for a more convenient way to resize images.

This operation does not change xres or yres. The image resolution needs to be updated by the application.

Optional arguments

See also

vips_shrink(), vips_resize(), vips_affine().

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.
vshrink

Type: double

Vertical reduce.

...

Type: 

NULL-terminated list of optional named arguments.

Return value

Type: int

0 on success, -1 on error.