make-image-access Function

Summary

Creates an Image Access object.

Package

graphics-ports

Signature

make-image-access port image => image-access

Arguments

port⇩	A graphics port.
image⇩	An image object.

Values

image-access⇩

An Image Access object.

Description

The function make-image-access returns an Image Access object for the given image image on port.

image can be any image object returned by make-image-from-port. An image object returned by load-image is also suitable, but only if it is a Plain Image (see below).

image-access is used when reading and writing the pixel values of the image. For an overview of using Image Access objects, see 13.10.8 Image access.

Notes

1. On some platforms (currently Windows) not every image object is a Plain Image. If needed, forcibly create a Plain Image suitable for passing to make-image-access as described in load-image.
2. Ensure that you eventually discard image-access, using free-image-access.

Examples

(example-edit-file "capi/graphics/image-access")

See also

free-image-access
image-access-transfer-from-image
image-access-transfer-to-image
image-access-height
image-access-pixel
load-image
make-image
13.10.8 Image access