The setinterceptcolorspace operator

This page applies to Harlequin v14.0r0 and later; both Harlequin Core and Harlequin MultiRIP.

dict setinterceptcolorspace -

null setinterceptcolorspace -

This operator is used to modify the effects of the setcolorspace and setcolor PostScript language operators. The effects can be summarized as causing device dependent color spaces to be replaced, or intercepted, with other color spaces.

This operator is subject to gsave and grestore semantics of the PostScript language.

The operand is normally a dictionary containing a subset of supported keys. All keys are optional, and the effect of multiple calls is accumulative, like setpagedevice. A null operand resets all keys to their default values.

This operator also intercepts device dependent color spaces when used as the base space of /Pattern and /Indexed spaces, or the alternate space of /Separation and /DeviceN spaces.

The details for each key are described in the following subsections.

DeviceCMYK, DeviceRGB, DeviceGray in setinterceptcolorspace

Value: color space, object-based dictionary, or null. Default: null.

When converting colors to the output device, this set of keys configures a replacement, or intercept, color space to use instead of an untagged device space of /DeviceCMYK, /DeviceRGB, or /DeviceGray. Intercept color spaces must have same number of color components as the original device space. Any valid PostScript language or PDF color space is allowed as the intercept color space, with the exceptions of Indexed and Pattern. This includes the use of Harlequin extension color spaces such as CMM custom color spaces, see Alternate CMMs: CMM custom color spaces .

The intercept color space may convert colors to:

• the XYZ or Lab connection space used in all PostScript language and PDF device independent color spaces. These are rendered using color management configured in setreproduction.
• a device space. If so:
  • if setreproduction is configured with a /NextDevice transform, and 
  • the device space matches the input of the /NextDevice transform, color management implied by the /NextDevice transform is applied.
  • otherwise, if the device space matches the output device, colors are sent directly to the device.
  • otherwise, colors are converted to the output device using the device space rules in section 7.2 of [RB3].

The default intercept color space is null, which has this behavior:

• for /DeviceCMYK and /DeviceRGB, the device color space is not intercepted.
• for /DeviceGray, if the /DeviceCMYK intercept color space is not null, convert Gray colors to CMYK and use the /DeviceCMYK intercept color space. Gray interception may be disabled independently of CMYK by specifying /DeviceGray as the value of /DeviceGray intercept profile.
• if the Profile directly in the currentreproduction dictionary matches the color model of the source color, this output profile is used as the intercept profile. The most common case is where setreproduction has a CMYK Profile and can be used as the /DeviceCMYK intercept.

Profiles in /NextDevice entries of setreproduction are ignored for this purpose.

• if no interception is performed, untagged device spaces are converted using the device space rules in section 7.2 of [RB3].

The value may be an object-based dictionary (see Object-based color management) to allow the four object types to be set independently. All keys are optional. Any unspecified keys assume the default value:

<<
  /Default <color-space>
  /Picture <color-space>
  /Text <color-space>
  /Shading <color-space>
  /Other <color-space>
>>

BlendCMYK, BlendRGB, BlendGray in setinterceptcolorspace

Value: color space, object-based dictionary, or null. Default: null.

When converting colors between transparency blend spaces, this set of keys configures a replacement, or intercept, color space to use instead of an untagged device space of /DeviceCMYK, /DeviceRGB, or /DeviceGray. Intercept color spaces must have the same number of color components as the original device space.

The only valid color space is ICCBased with a bidirectional profile. This reversibility requirement is essential for transparency blend spaces. It is also valid, albeit rarely done, to set values of /DeviceCMYK, /DeviceRGB, or /DeviceGray, which disables the intercept color spaces between transparency blend spaces without affecting the use of intercepts for conversion to the output device using the /DeviceCMYK, /DeviceRGB, and /DeviceGray keys.

The main reason these keys are required is to allow DeviceLink profiles and non-ICC color spaces to be used for color conversions to the output device, as configured in the /DeviceCMYK, /DeviceRGB, and /DeviceGray keys. Otherwise, the /BlendCMYK, /BlendRGB, and /BlendGray keys would normally be set to the default value of null. One common use case for production quality output is to use a DeviceLink ICC profile as the device color space intercept; the blend intercept ICC profile is normally configured to an ICC profile that matched the input profile in the device link.

The default intercept color space is null, which has this behavior:

• if the color space found in the corresponding /DeviceCMYK, /DeviceRGB, or /DeviceGray key is ICCBased with an ICC profile that can convert in both directions between the device space and the PCS, inherit it and use it for conversions between blend spaces.
• for /BlendGray, if the inherited value is also null and the /BlendCMYK intercept color space is not null, convert Gray colors to CMYK and use the /BlendCMYK intercept color space.
• if no interception is performed, untagged device spaces are converted using the device space rules in section 7.2 of [RB3].

The value may be an object-based dictionary (see Object-based color management) to allow the four object types to be set independently. All keys are optional. Any unspecified keys assume the default value:

<<
  /Default <color-space>
  /Picture <color-space>
  /Text <color-space>
  /Shading <color-space>
  /Other <color-space>
>>

SourceCMYK,  SourceRGB, SourceGray in setinterceptcolorspace

Value: color space, object-based dictionary, or null. Default: null.

When converting the original color of an object into its transparency blend space, this set of keys configures a replacement, or intercept, color space to use instead of an untagged device space of /DeviceCMYK, /DeviceRGB, or /DeviceGray. Intercept color spaces must have the same number of color components as the original device space. Any valid PostScript language or PDF color space is allowed as the intercept color space, with the exceptions of /Indexed and /Pattern. This includes the use of Harlequin extension color spaces such as CMM custom color spaces, (see Alternate CMMs: CMM custom color spaces).

These keys are rarely used, but are useful in some workflows. The default intercept color space is null, which has this behavior:

• if the color space in the corresponding /BlendCMYK, /BlendRGB, or /BlendGray key is not null, inherit it and use it.
• for /SourceGray, if the inherited value is also null and the /SourceCMYK intercept color space is not null, convert Gray colors to CMYK and use the /SourceCMYK intercept color space. Gray interception may be disabled independently of CMYK by specifying /DeviceGray as the value of the /SourceGray intercept profile.
• if no interception is performed, untagged device spaces are converted using the device space rules in section 7.2 of [RB3].

The value may be an object-based dictionary (see Object-based color management) to allow the four object types to be set independently. All keys are optional. Any unspecified keys assume the default value:

<<
  /Default <color-space>
  /Picture <color-space>
  /Text <color-space>
  /Shading <color-space>
  /Other <color-space>
>>

OverrideCMYK, OverrideRGB, OverrideGray in setinterceptcolorspace

Value: Boolean or object-based dictionary. Default: false.

This set of keys can be used to override, or ignore, device independent color spaces.

Device-independent color spaces are evaluated to determine if they are a tagged device space. If so, and the corresponding /OverrideCMYK, /OverrideRGB, or /OverrideGray value is true, the tagged device space is temporarily treated as the nearest device space and then replaced with the intercept color space using the appropriate intercept from the Device*, Blend*, and Source* keys.

The value may be an object-based dictionary (see Object-based color management)  to allow the four object types to be set independently. All keys are optional. Any unspecified keys assume the default value:

<<
  /Default <boolean>
  /Picture <boolean>
  /Text <boolean>
  /Shading <boolean>
  /Other <boolean>
>>

NamedColor in setinterceptcolorspace

Value: array of names, or null. Default: null.

This key configures named color management which is described in Named color management. It is used to replace the alternate space and tint transform of named colors when used in Separation and /DeviceN spaces.

The value is an array of the names of named color resources, NCDs. These are searched in turn for a reference to a named color and the alternate space and tint transform from that NCD is used as the replacements.

For example: [ /PantoneCoated /PantoneUncoated ]

A value of null disables named color management.

OverprintPreview in setinterceptcolorspace

Value: Boolean or /SpotsOnly. Default: false.

Switches the RIP into a mode where it emulates a virtual device that supports spot overprints along with other benefits. This option is described in detail in Understanding OverprintPreview.

The allowed values are: 

Black in setinterceptcolorspace 

Value: Boolean or object-based dictionary. Default: true.

With the default value of true, pure black (100%) is color managed the same as other colors. The resulting non-pure color could be undesirable for text or linework.

A value of false preserves 100% pure black colors, and ignores color management that may be applied to other colors. 100% pure black preservation only applies to Text and Other (linework) objects. It is, therefore, disabled for Picture and Shading objects. The feature is described in detail in Black preservation.

The value may be an object-based dictionary (see Object-based color management), which allows the valid object type/color model combinations to be set independently. All keys are optional:

<<
  /Default <boolean>
  /Text <color-model-dict>
  /Other <color-model-dict>
>>

where <color-model-dict> contains values for object type/color model combinations. All keys are optional. Any unspecified keys assume the default value:

<<
  /Default <boolean>
  /CMYK <boolean>
  /RGB <boolean>
  /Gray <boolean>
  /NamedColor <boolean>
  /CIE <boolean>
>>

BlackTint in setinterceptcolorspace

Value: boolean, or object-based dictionary. Default: true.

With the default value of true, tints of pure black are color managed the same as other colors. The resulting non-pure color could be undesirable for text or linework.

A value of false preserves tints of pure black colors, and ignores color management that may be applied to other colors. The value of the preserved black depends on the /BlackTintLuminance key and the details of the color configuration. Black tint preservation only applies to Text and Other (linework) objects. It is, therefore, disabled for Picture and Shading objects. The feature is described in detail in Black preservation.

If both 100% pure black and black tint preservation are active, 100% pure blacks are preserved in preference to the black tint.

The value may be an object-based dictionary (see Object-based color management), which allows the valid object type/color model combinations to be set independently. All keys are optional:

<<
  /Default <boolean>
  /Text <color-model-dict>
  /Other <color-model-dict>
>>

where <color-model-dict> contains values for object type/color model combinations. All keys are optional. Any unspecified keys assume the default value:

<<
  /Default <boolean>
  /CMYK <boolean>
  /RGB <boolean>
  /Gray <boolean>
  /NamedColor <boolean>
  /CIE <boolean>
>>

BlackTintLuminance in setinterceptcolorspace

Value: boolean. Default: true.

This value modifies the behavior of the black tint preservation when the /BlackTint value is false. The feature is described in detail in Black tint preservation).

If /BlackTintLuminance is true, the RIP preserves the luminance of the tint of pure black, where possible. If it is not possible to preserve the luminance, or if the value is false, the original black value is preserved.

ConvertRGBBlack in setinterceptcolorspace

ConvertRGBBlack has been deprecated and should not be used in new code.

This controls the conversion of RGB black to pure CMYK black. Use the /Black key instead.

MultipleNamedColors in setinterceptcolorspace

MultipleNamedColors has been deprecated and should not be used in new code.

The value should not be changed from the default of true.