All Manuals > CAPI User Guide and Reference Manual > 22 GRAPHICS-PORTS Reference Entries

list-known-image-formats Function

Summary

Returns the known image formats.

Package

graphics-ports

Signature

list-known-image-formats screen-spec &optional for-writing-too => formats

Arguments
screen-spec
A CAPI object, a plist, or nil.
for-writing-too
A generalized boolean.
Values
formats
A list of keywords.
Description

The function list-known-image-formats returns a list of keywords which specify known image formats.

screen-spec is an object that convert-to-screen can recognize, typically a pane or simply nil.

If for-writing-too is not supplied or is nil, then formats is a list of formats that can be loaded. All the formats in the list can be loaded, but on Cocoa and Windows the list is not exhaustive, and it may be possible to load formats that are not listed.

If for-writing-too is supplied as non-nil, then formats is a list of types that externalize-and-write-image can write. In this case the list is exhaustive on all platforms, and externalize-and-write-image can write a format if and only if it appears in the list.

All platforms (except Motif) can read and write :bmp, :jpg, :png and :tiff images, and also recognize :jpeg as an alias for :jpg, so the list will always include all of these keywords.

See also

convert-to-screen
externalize-and-write-image
13 Drawing - Graphics Ports


CAPI User Guide and Reference Manual (Macintosh version) - 01 Dec 2021 19:31:44