Harlequin RIP SDK

This example provides a core color management example module that acts as an interface to Microsoft's Image Color Management (ICM2) library. More...

Files

file  cmm_icm2.h
 Interface to an example CMM using Microsoft's Image Color Management.
 
file  cmm_icm2.c
 CMM Implementation of the interface to the Microsoft's Image Color Management.
 

Functions

sw_cmm_apiicm2_getInstance (void)
 Return the singleton instance of a sw_cmm_api object containing details specific to the ICM2 CMM example module. More...
 
static HqBool icm2_init (sw_cmm_api *implementation, const sw_cmm_init_params *params)
 Callback function to ask us to initialise the module. More...
 
static void icm2_finish (sw_cmm_api *implementation)
 Callback function to ask us to tidy up when closing the module. More...
 
static sw_cmm_result icm2_construct (sw_cmm_instance *instance)
 Construct an instance of the sw_cmm_api interface. More...
 
static sw_cmm_result icm2_open_profile (sw_cmm_instance *instance, sw_blob_instance *ICC_profile, sw_cmm_profile *handle)
 Create an internal profile structure for ICC profile data stored in memory. More...
 
static void icm2_close_profile (sw_cmm_instance *instance, sw_cmm_profile profile)
 Close a profile with a handle previously created with icm2_open_profile(). More...
 
static sw_cmm_result icm2_open_transform (sw_cmm_instance *instance, sw_cmm_profile profiles[], uint32 num_profiles, int32 intents[], HqBool black_point_compensations[], uint32 *num_input_channels, uint32 *num_output_channels, sw_cmm_transform *handle)
 Create a transform structure. More...
 
static void icm2_close_transform (sw_cmm_instance *instance, sw_cmm_transform transform)
 Close a transform previously opened with icm2_open_transform(). More...
 
static sw_cmm_result icm2_invoke_transform (sw_cmm_instance *instance, sw_cmm_transform transform, float *input_data, float *output_data, uint32 num_pixels)
 Use the specified transform to adjust color data. More...
 

Detailed Description

This example provides a core color management example module that acts as an interface to Microsoft's Image Color Management (ICM2) library.

To configure the RIP to use this color management module, use this fragment in the configuration PostScript:

(CMM_ICM2) setalternatecmm

With this configuration, color transforms involving ICC profiles will be directed to this module, which in turn will use the ICM2 API. Further details in the extensions manual.

This example module is registered by calling SwRegisterCMM() with the singleton API instance returned by icm2_getInstance(). The module implements the CMM API methods icm2_init(), icm2_finish(), icm2_construct(), icm2_destruct(), icm2_open_profile(), icm2_close_profile(), icm2_open_transform(), icm2_close_transform() and icm2_invoke_transform().

Function Documentation

◆ icm2_close_profile()

static void icm2_close_profile ( sw_cmm_instance instance,
sw_cmm_profile  profile 
)
static

Close a profile with a handle previously created with icm2_open_profile().

Parameters
[in]instanceThe alternate CMM instance owning the profile.
[in]profileA profile handle previous opened by an open_profile() or open_custom_colorspace() calls on the same alternate CMM instance. The alternate CMM implementation should discard any resources associated with the profile.
See also
icm2_open_profile()

◆ icm2_close_transform()

static void icm2_close_transform ( sw_cmm_instance instance,
sw_cmm_transform  transform 
)
static

Close a transform previously opened with icm2_open_transform().

Parameters
[in]instanceThe alternate CMM instance owning the color transform.
[in]transformA valid transform handle created by an open_transform() or open_transform2() call on the same alternate CMM instance. The alternate CMM implementation should discard any resources associated with the transform.
See also
icm2_open_transform()

◆ icm2_construct()

static sw_cmm_result icm2_construct ( sw_cmm_instance instance)
static

Construct an instance of the sw_cmm_api interface.

The RIP constructs an instance for each CMM module after booting the interpreter. RIP fills in the implementation pointer, and pointers to the memory API and blob API instances. The module is expected to fill in the remaining fields, which contains flags defining of the implementation capabilities of the module. Some of the information returned will be used by the RIP to determine whether a particular profile or transform can be handled by this module, and in other cases the RIP will use this information to divert color conversions through its built-in CMM if appropriate.

Parameters
[in,out]instanceAn incomplete instance of the sw_cmm_instance structure to complete. The RIP will allocate a structure of the size presented in the implementation's sw_cmm_api::info.instance_size field, fill in the implementation and callback API instance pointers, and then pass it to this routine. The construct() method is expected to fill in the remaining fields. The implementation may sub-class the instance to allocate private workspace by initialising the implementation's sw_cmm_api::info.instance_size larger than the size of the sw_cmm_instance structure, then downcasting the instance pointer in method calls.
Returns
SW_CMM_SUCCESS if the instance is fully constructed, otherwise one of the SW_CMM_RESULT error codes.

◆ icm2_finish()

static void icm2_finish ( sw_cmm_api implementation)
static

Callback function to ask us to tidy up when closing the module.

The implementation instances should not access any data owned by the RIP after this call, nor should they call any implementation or RIP callback API methods after this call. This method is optional; if not required, set to NULL.

Parameters
implementationA registered alternate CMM implementation to finalise.

◆ icm2_getInstance()

sw_cmm_api* icm2_getInstance ( void  )

Return the singleton instance of a sw_cmm_api object containing details specific to the ICM2 CMM example module.

Returns
A single instance of the CMM.
See also
SwRegisterCMM()

If compiled normally, the "clrip" application layer registers this module during RIP startup. CMM module examples may be excluded from "clrip" by building with NO_CMMEG defined.

◆ icm2_init()

static HqBool icm2_init ( sw_cmm_api implementation,
const sw_cmm_init_params params 
)
static

Callback function to ask us to initialise the module.

This method may be used to initialise any implementation-specific data. This method is optional; if not required, set to NULL.

Parameters
implementationThe registered alternate CMM implementation to be initialised.
[in]paramsA structure containing callback APIs and parameters valid for the lifetime of the module. Any parameters that the implementation needs access to should be copied out of this structure into private storage for the registered implementation.
Return values
TRUESuccess, indicating that the implementation is fully initialised.
FALSEFailure to initialize the implementation. If this is returned, the implementation will not be finalized.

◆ icm2_invoke_transform()

static sw_cmm_result icm2_invoke_transform ( sw_cmm_instance instance,
sw_cmm_transform  transform,
float *  input_data,
float *  output_data,
uint32  num_pixels 
)
static

Use the specified transform to adjust color data.

The RIP will place color data in memory beginning at input_data. This function should convert the data using the transform and place the output values in memory beginning at output_data.

ICM2 and the RIP store pixel data in different formats so this code uses convertFloatToWORDArray() and convertWORDToFloatArray() to convert the data to the appropriate format.

Parameters
[in]instanceThe alternate CMM instance owning the color transform.
[in]transformA valid transform handle created by an open_transform() call on the same alternate CMM instance.
[in]input_dataAn array of num_pixels sets of pixel-interleaved color values to transform. Colors are interleaved in the order specified by the input space of the first profile in the transform.
[out]output_dataAn array in which to store num_pixels sets of pixel-interleaved color values. Colors are interleaved in the order specified by the output space of the last profile in the transform.
num_pixelsThe number of sets of input pixel colorvalues to convert from the input space to the output space of the transform.
Returns
SW_CMM_SUCCESS if the invocation succeeded, one of the SW_CMM_RESULT error codes otherwise.

In all cases, both the input and output data should be pixel interleaved with each color value contained in a 32-bit IEEE floating value. The interleaving of the input data is in the same order as that expected by the first profile in a transform and the interleaving of the output data should be in the same order as produced by the last profile in the transform. It is the responsibility of the alternate CMM to marshal the data into and out of the format required for its internal use. As an example, if five pixels of RGB data were to be converted to CMYK, the RIP will arrange the input data as follows:

RGBRGBRGBRGBRGB

and invoke_transform() will produce this arrangement of output data:

CMYKCMYKCMYKCMYKCMYK

The number of channels for each pixel is derived from the first and last profiles in the transform as returned by open_transform().

The memory referenced by input_data and output_data is managed by the RIP and can be assumed to contain valid memory for the appropriate amount of data. The size, in bytes, allocated by the RIP to each is:

  • input_data: num_pixels * num_input_channels * sizeof(float)
  • output_data: num_pixels * num_output_channels * sizeof(float)
See also
icm2_open_transform()

◆ icm2_open_profile()

static sw_cmm_result icm2_open_profile ( sw_cmm_instance instance,
sw_blob_instance ICC_profile,
sw_cmm_profile handle 
)
static

Create an internal profile structure for ICC profile data stored in memory.

Parameters
[in]instanceThe alternate CMM implementation instance owning the ICC profile.
[in]ICC_profileA blob data source, giving access to the raw ICC profile data through the blob's sw_blob_api implementation methods. This blob will have been opened for non-exclusive read access. If the alternate CMM wishes to use the data source after the open_profile() method returns, it must create a new blob reference using the sw_blob_api::open_blob() method, and use that reference for all access after open_profile() terminates. If a new blob reference is created, the alternate CMM implementation must close that reference when it has finished accessing to it.
[out]handleA pointer in which a CMM profile handle is stored. This handle will be used to refer to the profile by close_profile(), open_transform(), and open_transform2().
Returns
SW_CMM_SUCCESS if the profile was successfully opened, in which case a non-NULL profile pointer should have been stored in handle. If the profile could not be opened, one of the SW_CMM_RESULT error codes is returned.

If a valid profile handle is returned, the close_profile() method will be called to destroy the profile later.

See also
icm2_close_profile(), icm2_open_transform()

◆ icm2_open_transform()

static sw_cmm_result icm2_open_transform ( sw_cmm_instance instance,
sw_cmm_profile  profiles[],
uint32  num_profiles,
int32  intents[],
HqBool  black_point_compensations[],
uint32 num_input_channels,
uint32 num_output_channels,
sw_cmm_transform handle 
)
static

Create a transform structure.

Prior to creating a transform the RIP will ensure compatibility with the capabilities of this CMM as indicated by its optional capabilities. If the transform isn't compatible then color conversion will be attempted using the RIP's built-in CMM instead.

The RIP will have previously opened the profiles that are passed in as arguments.

In this example the rendering intent is obtained from the first profile specified in the sequence.

Parameters
[in]instanceThe alternate CMM instance owning the profiles.
[in]profilesAn array of num_profiles profile handles, returned by calls to open_profile() or open_custom_colorspace().
num_profilesThe number of profiles in the transform chain.
[in]intentsAn array of length num_profiles-1 specifying the rendering intents use for color conversions between adjacent profiles in the profiles parameter.
[in]black_point_compensationsAn array of length num_profiles-1 containing boolean flags, indicating if black point compensation is performed when converting colors between adjacent profiles in the profiles parameter.
[out]num_input_channelsA location for the alternate CMM to fill in the number of color channels in the input space of the first profile in the transform.
[out]num_output_channelsA location for the alternate CMM to fill in the number of color channels in the output space of the last profile in the transform.
[out]handleA pointer in which a CMM transform handle is stored by the alternate CMM implementation. This handle will be used to refer to the transform by close_transform() and invoke_transform() methods.
Returns
SW_CMM_SUCCESS if the transform was successfully opened, in which case a non-NULL transform pointer should have been stored in handle. If the profile could not be opened, one of the SW_CMM_RESULT error codes is returned.

If a valid transform handle is returned, the close_transform() method will be called to destroy the transform later.

See also
icm2_close_transform(), icm2_invoke_transform()