NCWConcatColorWorld
Defines a color world for color transformations among a series of concatenated profiles.
Declaration
CMError NCWConcatColorWorld (
CMWorldRef *cw,
NCMConcatProfileSet *profileSet,
CMConcatCallBackUPP proc,
void *refCon
);Parameters
- cw:
A reference to a color world that the ColorSync Manager returns if the function completes successfully. You pass this reference to other functions that use the color world for color-matching and color-checking sessions.
- profileSet:
An array of profiles describing the processing to be carried out. The array is in processing order source through destination.
- proc:
A calling-program-supplied callback function that allows your application to monitor progress or abort the operation.
- refCon:
A reference constant containing data specified by the calling application program.
Return Value
A CMError value. See Result Codes.
Overview
The caller can override the color management module (CMM) that would normally be selected by ColorSync by providing a CMM identifier in the NCMConcatProfileSet structure, or pass 0 to accept ColorSync's CMM selection (note that this could either be the user's preferred CMM selection or the CMM called for in the profile). The flags and k parameters are provided to allow easy customization of such attributes as quality and gamut-checking, while preserving the other settings. Each profile in the set can be customized by overriding the intent, and the selection of the transform tag. Together with other profiles, a custom-rendering environment can be set up to transform to or from device-dependent spaces with a minimum of gamut compression and/or unnecessary transformations to and from connection spaces. This flexibility comes at the price of specific knowledge of the profile contents and how device gamuts overlap.
Note that for standard input and output device profiles, A2B and B2A tags represent transforms from data space to connection space and from connection space to data space, respectively. Under these circumstances, the caller would not normally be able to use the same transform tags (e.g., kUseAtoB ) consecutively, since a connection space would not be the same as the subsequent data space. If the spaces aren't the same, the caller will get a cmCantConcatenateError error returned. For profiles of type cmLinkClass, cmAbstractClass, cmColorSpaceClass , and cmNamedColorClass , these constants are not always meaningful, and the caller is encouraged to think in terms of the actual tags present in the profiles (e.g., A2B0 or B2A0 ). Under these conditions, it may well be appropriate to specify two transform tags of the same type consecutively, as long as the actual color spaces align in between tags. If this is not the case, a cmCantConcatenateError error is returned.
The callback proc is provided as protection against the appearance of a stalled machine during lengthy color world processing. If a CMM takes more than several seconds to process the information and create a color world, it will call the callback proc, if one is provided, and pass it the refCon provided. This is also true for NCWNewLinkProfile.