CIImageProvider Protocol Reference
(informal protocol)
| Adopted by | |
| Framework | Library/Frameworks/QuartzCore.framework |
| Availability | Available in OS X v10.4 and later |
| Companion guide | |
| Declared in | CIImageProvider.h |
Overview
The CIImageProvider informal protocol defines methods for supplying bitmap data to create or initialize a CIImage object.
Instance Methods
provideImageData:bytesPerRow:origin:size:userInfo:
Supplies data to a CIImage object.
Parameters
- data
A pointer to image data. Note that
data[0]refers to the first byte of the requested subimage, not the larger image buffer.- rowbytes
The number of bytes per row.
- x
The x origin of the image data.
- y
The y origin of the image data.
- width
The width of the image data.
- height
The height of the image data.
- info
User supplied data, which is optional.
Discussion
You can supply the image provider to these methods of the CIImage class:
imageWithImageProvider:size::format:colorSpace:options:to create a CIImage object from image datainitWithImageProvider:size::format:colorSpace:options:to initialize an existing CIImage with data
You initialize the given bitmap with the subregion specified by the arguments x, y, width, and height. The subregion uses the local coordinate space of the image, with the origin at the upper-left corner of the image. If you change the virtual memory mapping of the buffer specified by the data argument (such as by using vm_copy to modify it), the behavior is undefined.
That this callback always requests the full image data regardless of what is actually visible. All of the image is loaded or none of it is. The exception is when you create a tiled image by specifying the kCIImageProviderTileSize option. In this case, only the needed tiles are requested.
Constants
Image Provider Options
Keys for the options dictionary of an image provider.
NSString *kCIImageProviderTileSize; NSString *kCIImageProviderUserInfo;
Constants
kCIImageProviderTileSizeA key for the image tiles size. The associated value is an
NSArraythat containsNSNumberobjects for the dimensions of the image tiles requested from the image provider.Available in OS X v10.4 and later.
Declared in
CIImageProvider.h.kCIImageProviderUserInfoA key for data needed by the image provider. The associated value is an object that contains the needed data.
Available in OS X v10.4 and later.
Declared in
CIImageProvider.h.
Discussion
You can use these options when you create or initialize an image provider with such methods as imageWithImageProvider:size::format:colorSpace:options: or initWithImageProvider:size::format:colorSpace:options:.
© 2009 Apple Inc. All Rights Reserved. (Last updated: 2009-11-17)