Vips.Region¶

Subclasses:: None

Methods¶

Inherited:: Vips.Object (27), GObject.Object (37)
Structs:: Vips.ObjectClass (1), GObject.ObjectClass (5)

class	`new` (image)
	`black` ()
	`buffer` (r)
	`copy` (dest, r, x, y)
	`equalsregion` (reg2)
	`fetch` (left, top, width, height, len)
	`height` ()
	`image` (r)
	`invalidate` ()
	`paint` (r, value)
	`paint_pel` (r, ink)
	`position` (x, y)
	`prepare` (r)
	`prepare_to` (dest, r, x, y)
	`region` (dest, r, x, y)
	`shrink_method` (to, target, method)
	`width` ()

Virtual Methods¶

Inherited:: Vips.Object (9), GObject.Object (7)

Properties¶

Inherited:: Vips.Object (2)

Signals¶

Inherited:: Vips.Object (4), GObject.Object (1)

Fields¶

Inherited:: Vips.Object (4), GObject.Object (1)

Name	Type	Access	Description
bpl	`int`	r
data	`int`	r
im	`Vips.Image`	r	the `Vips.Image` that this region is defined on
invalid	`bool`	r
parent_object	`Vips.Object`	r
seq	`object`	r
thread	`GLib.Thread`	r
type	`object`	r
valid	`Vips.Rect`	r	the `Vips.Rect` of pixels that this region represents
window	`object`	r

Class Details¶

class Vips.Region(**kwargs)¶

Bases:: Vips.Object
Abstract:: No
Structure:: Vips.RegionClass

A small part of a Vips.Image. valid holds the left/top/width/height of the area of pixels that are available from the region.

See also: VIPS_REGION_ADDR(), Vips.Region.new(), Vips.Region.prepare().

classmethod new(image)¶

Parameters:: image (Vips.Image) – image to create this region on
Return type:: Vips.Region

Create a region. Vips.Region s start out empty, you need to call Vips.Region.prepare() to fill them with pixels.

See also: Vips.Region.paint().

equalsregion(reg2)¶

Parameters:: reg2 (Vips.Region) – region to test
Returns:: non-zero on equality.
Return type:: int

Do two regions point to the same piece of image? ie.

VIPS_REGION_ADDR(reg1, x, y) == VIPS_REGION_ADDR(reg2, x, y) &&
*VIPS_REGION_ADDR(reg1, x, y) ==
    *VIPS_REGION_ADDR(reg2, x, y) for all x, y, reg1, reg2.

fetch(left, top, width, height, len)¶

Parameters:

left (int) – area of pixels to fetch
top (int) – area of pixels to fetch
width (int) – area of pixels to fetch
height (int) – area of pixels to fetch
len (int) –

Returns:

A copy of the pixel data.

Return type:

int

Generate an area of pixels and return a copy. The result must be freed with GLib.free(). The requested area must be completely inside the image.

This is equivalent to Vips.Region.prepare(), followed by a memcpy. It is convenient for language bindings.

height()¶

Returns:: Height of the pixels held in region.
Return type:: int

image(r)¶

Parameters:: r (Vips.Rect) – Vips.Rect of pixels you need to be able to address
Returns:: 0 on success, or -1 for error.
Return type:: int

The region is transformed so that at least r pixels are available to be read from the image. The image needs to be a memory buffer or represent a file on disc that has been mapped or can be mapped.

invalidate()¶

Mark a region as containing invalid pixels. Calling this function means that the next time Vips.Region.prepare() is called, the region will be recalculated.

This is faster than calling Vips.Image.invalidate_all(), but obviously only affects a single region.

paint(r, value)¶

Parameters:

r (Vips.Rect) – area to paint
value (int) – value to paint

Paints value into self covering rectangle r. r is clipped against self->valid.

For int images, value is passed to memset(), so it usually needs to be 0 or 255. For float images, value is cast to a float and copied in to each band element.

r is clipped against self->valid.