Surface Point Color CIELab Value Data Attribute
| Tag | (0080,0007) |
|---|---|
| Type | Optional (3) |
| Keyword | SurfacePointColorCIELabValueData |
| Value Multiplicity | 3-3n |
| Value Representation | Unsigned Short (US) |
Contains a vector of color triplets to assign colors to each point.
The number of triplets shall be equal to the value of Number Of Surface Points (0066,0015) in the Points Macro.
The units are PCS-Values, and the value is encoded as CIELab. See Section C.10.7.1.1.
Each triplet shall correspond to the respective point in the Point Coordinates Data (0066,0016).
Points Macro
C.27.2 Points Macro
Table C.27-2 specifies the Attributes of the Points Macro.
Table C.27-2. Points Macro Attributes
|
Attribute Name |
Tag |
Type |
Attribute Description |
|---|---|---|---|
|
Number Of Surface Points |
(0066,0015) |
1 |
Specifies the number of points in the point set. See Section C.27.2.1.1. |
|
Point Coordinates Data |
(0066,0016) |
1 |
|
|
Point Position Accuracy |
(0066,0017) |
3 |
A single standard deviation of the error for all the points' spatial positions. The units shall be the same as the units of the coordinate system in which the point coordinates are specified. |
|
Mean Point Distance |
(0066,0018) |
3 |
The mean point distance of the point set. It is given by the mean of the distances to the nearest neighbor over all points. The units shall be the same as the units of the coordinate system in which the point coordinates are specified. |
|
Maximum Point Distance |
(0066,0019) |
3 |
The maximum distance of one point to its nearest neighbor. The units shall be the same as the units of the coordinate system in which the point coordinates are specified. |
|
Points Bounding Box Coordinates |
(0066,001A) |
3 |
Two 3D locations defining the cuboid bounding box, parallel to the coordinate system axes, encompassing the point set. |
|
Axis of Rotation |
(0066,001B) |
3 |
A 3D location that combined with Center of Rotation (0066,001C) specifies the preferred axis of rotation of this object. |
|
Center of Rotation |
(0066,001C) |
1C |
A 3D location defining the preferred center of rotation for this point set. Required if Axis of Rotation (0066,001B) is present. May be present otherwise. |
C.27.2.1 Points Macro Attribute Descriptions
All Attributes within this Macro containing points or vectors are in x-y-z order. If multiple elements are encoded, the ordering is x1,y1,z1,…,xn,yn,zn.
The points are in the coordinate system identified by the Frame of Reference UID (0020,0052). To map these points into the coordinate system of another SOP Instance a Spatial Registration Instance can be used.
C.27.2.1.1 Point Coordinates Data
When referencing individual points the index of the first point shall be 1.
Section C.10.7.1.1
C.10.7.1.1 Encoding of CIELab Values
Attributes such as Graphic Layer Recommended Display CIELab Value (0070,0401) consist of three unsigned short values:
-
An L value linearly scaled to 16 bits, such that 0x0000 corresponds to an L of 0.0, and 0xFFFF corresponds to an L of 100.0.
-
An a* then a b* value, each linearly scaled to 16 bits and offset to an unsigned range, such that 0x0000 corresponds to an a* or b* of -128.0, 0x8080 corresponds to an a* or b* of 0.0 and 0xFFFF corresponds to an a* or b* of 127.0
Note
This is the same form of encoding as used for the PCS in ICC Profiles.