DICOM PS3.3 2024e - Information Object Definitions

C.27.6 UV Mapping Module

Table C.27.6-1 specifies the Attributes of the UV Mapping Module.

Table C.27.6-1. UV Mapping Module Attributes

Attribute Name

Tag

Type

Attribute Description

UV Mapping Sequence

(0080,0008)

1

Maps each point of the Surface Points Sequence (0066,0011) in the Point Cloud Module or the Surface Mesh Module to the coordinates of a VL Photographic Image Instance.

One or more Items shall be included in this Sequence.

>Referenced Surface Number

(0066,002C)

1C

Identifies the Surface Number (0066,0003) of the Item in Surface Sequence (0066,0002) to which this UV Mapping applies.

Required when Surface Sequence (0066,0002) is present and contains more than one Item.

>Texture Label

(0080,0009)

1

Contains a label that uniquely identifies this UV map to distinguish it from other Items in the Sequence.

>U Value Data

(0080,0010)

1

Contains a vector of column offsets. Each value is normalized to the range of 0.0 to 1.0 pointing in the pixel data of the referenced textures Sequence image. Each value shall correspond to the respective point in the Point Coordinates Data (0066,0016).

The number of values must be equal to the number of points of the Point Cloud or the Surface Mesh.

>V Value Data

(0080,0011)

1

Contains a vector of row offsets. Each value is normalized to the range of 0.0 to 1.0 pointing in the pixel data of the referenced textures Sequence image. Each value shall correspond to the respective point in the Point Coordinates Data (0066,0016).

The number of values must be equal to the number of points of the Point Cloud or the Surface Mesh.

>Referenced Texture Sequence

(0080,0012)

1

The image that is being mapped to the point cloud or the surface mesh.

Only a single Item shall be included in this Sequence.

>>Include Table 10-3 “Image SOP Instance Reference Macro Attributes”


C.27.6.1 UV Mapping Attribute Description

C.27.6.1.1 U Value Data and V Value Data

UV texturing allows a 3D object to be colored with the color from a 2D image. The 2D image therefore is called texture map. During the UV mapping process pixels from the 2D image are assigned to each point in the point cloud or the surface mesh of the object. The 2D image shall fully cover the space of the scanned object. If more than one texture with different resolutions or different exposures is required separate SOP Instances shall be created.

The term U and V is used because X, Y and Z are already assigned to the coordinates of the points of the scanned object.

Example of mapping textures to point coordinates.

Figure C.27.6.1.1-1. Example of mapping textures to point coordinates.


DICOM PS3.3 2024e - Information Object Definitions