H.4.9. Presentation LUT SOP Class

H.4.9.1 Information Object Description

The Presentation LUT Information Object is an abstraction of a Presentation LUT (see Section H.2.1.1). The objective of the Presentation LUT is to realize image display tailored for specific modalities, applications, and user preferences. It is used to prepare image pixel data for display on devices that conform to the Grayscale Standard Display Function defined In PS 3.14.

Note: The density range to be printed, Min Density to Max Density, is specified at either the Film Box or the Image Box. As follows from the definition for Min Density and Max Density in PS 3.3, if the requested minimum density is lower than the minimum printer density, or the requested maximum density is greater than the maximum printer density, the printer will use its minimum or maximum density, respectively, when computing the standard response.

The output of the Presentation LUT is Presentation Values (P-Values). P-Values are approximately related to human perceptual response. They are intended to facilitate common input for both hardcopy and softcopy display devices. P-Values are intended to be independent of the specific class or characteristics of the display device.

The Presentation LUT is not intended to alter the appearance of the pixel values, as specified as specified by the Photometric Interpretation (0028,0004) and Polarity (2020,0020).

The Basic Film Box Information Object, the Basic Image Box Information Object and the Referenced Image Box Object reference the Presentation LUT.

If the Configuration Information Attribute (2010,0150) of the Basic Film Box IOD contains information similar to the Presentation LUT, then the Presentation LUT Attributes shall take precedence.

H.4.9.1.1 Mapping of P-Values to Optical Density

The mathematical definition of the Grayscale Standard Display Function and mapping of P-Values to optical density for reflective and transmissive printers is contained in PS 3.14.

H.4.9.2 DIMSE Service Group

The following DIMSE Services are applicable to the association related Presentation LUT Information Object:

DIMSE Service Element Usage SCU/SCP
N-CREATE M/M
N-DELETE U/M

The meaning of the Usage SCU/SCP is described in section H.2.4.

This section describes the behavior of the DIMSE Services, which are specific for this Information Object. The general behavior of the DIMSE services is specified in Part 7 of this Standard.

H.4.9.2.1 N-CREATE

The N-CREATE Service Element is used to create an instance of the Presentation LUT SOP Class.

H.4.9.2.1.1 Attributes

The Attribute list of the N-CREATE Service Element is defined as shown in Table H.4-23.

Table H.4-23N-CREATE ATTRIBUTE LIST

Attribute name Tag Usage SCU/SCP
Presentation LUT Sequence (2050,0010) MC/M (Required if Presentation LUT Shape (2050,0020) is not present. Not allowed otherwise.)
>LUT Descriptor (0028,3002) MC/M (Required if sequence is present. The first value (number of entries in the LUT) shall be equal to 256 if Bits Stored = 8 4096 if Bits Stored = 12. The second value shall be equal to 0. The third value (number of bits for each LUT entry) shall be 10-16.) See the definition is PS 3.3 for further explanation.
>LUT Explanation (0028,3003) U/U
>LUT Data (0028,3006) MC/M (Required if sequence is present)
Presentation LUT Shape (2050,0020) MC/M (Required if Presentation LUT Sequence (2050,0010) is not present. Not allowed otherwise.) SCPs shall support the Enumerated Values IDENTITY and LIN OD

H.4.9.2.1.2 Status

The status values which are specific for this SOP Class are defined as follows:

Status Meaning Code
Success Presentation LUT successfully created 0000
Warning Requested Min Density or Max Density outside of printer’s operating range. The printer will use its respective minimum or maximum density value instead. B605

H.4.9.2.1.3 Behavior

The SCU uses the N-CREATE Service Element to request the SCP to create a Presentation LUT SOP Instance. The SCU shall initialize Attributes of the SOP Class as specified in section H.2.4.

The SCU shall create the Presentation LUT prior to referencing it from the Film Box or the Image Box.

The Presentation LUT persists in the SCP as long as the Association in which it was created is open or an explicit N-DELETE is issued by the SCU.

The SCP shall return the status code of the requested SOP Instance creation. The meaning of success, warning, and failure status codes is defined in Section H.2.5.

The SCP shall use the Grayscale Standard Display Function as specified in PS 3.14 to convert the output of the Presentation LUT to density for printing. If the SCU specifies values for Illumination (2010,015E) and/or Reflected Ambient Light (2010,0160), these values shall be used instead of the default or configured values of the SCP. If these values are not supplied, the SCP shall use its default or configured values. (See H.4.2.2.1.1 for suggested defaults).

H.4.9.2.2 N-DELETE

The N-DELETE Service Element is used to delete the Presentation LUT SOP Instance.

H.4.9.2.2.1 Status

There are no specific error codes

H.4.9.2.2.2 Behavior

The SCU uses the N-DELETE Service Element to request the SCP to delete the Presentation LUT SOP Instance. The SCU shall specify the Presentation LUT SOP Instance UID.

The SCP shall not delete a Presentation LUT SOP Instance as long as there are outstanding references to it. Otherwise, it shall delete the specified Presentation LUT SOP Instance. The N-DELETE of a Presentation LUT will prevent the SCU from further referencing it. The SCU shall not reference a previously deleted Presentation LUT. The SCP shall return the status code of the requested Presentation LUT SOP Instance deletion. The meaning of success, warning, and failure status codes is defined in Section H.2.5.

H.4.9.2.4 SOP Class Definition and UID

The Presentation LUT SOP Class UID is “1.2.840.10008.5.1.1.23”.