C.8.12.4.1 VL Whole Slide Microscopy Image Attribute Descriptions

C.8.12.4.1.1 Image Type

Image Type (0008,0008) is specified to be Type 1 with the following constraints:

Value 1 shall have a value of ORIGINAL or DERIVED

Value 2 shall have a value of PRIMARY

Value 3 (Image Flavor) shall have the Defined Terms in Table C.8.12.4-2

Table C.8.12.4-2VL WHOLE SLIDE MICROSCOPY IMAGE FLAVORS

LOCALIZER Collected for the purpose of planning or navigating other images.
VOLUME Set of frames that define a regularly sampled volume
LABEL Purpose of image is to capture the slide label; any non-label area captured is incidental to that purpose.

Value 4 (Derived Pixel) shall have the Defined Terms specified in Table C.8.12.4-3.

Table C.8.12.4-3VL WHOLE SLIDE MICROSCOPY DERIVED PIXELS

NONE No derivation of pixels (original)
RESAMPLED Pixels were derived by down sampling a higher resolution image

No additional values shall be present.

C.8.12.4.1.2 Imaged Volume Width, Height, Depth

The full physical extent of the whole slide image target volume is described in the attributes Imaged Volume Width (0048,0001), Imaged Volume Height (0048,0002), and Imaged Volume Depth (0048,0003). These values reflect the maximum extent in these dimensions. There is no requirement that this entire extent is actually encoded in frames of the Image SOP Instance.

The value of Imaged Volume Depth (0048,0003) shall not be 0. If only a single focal plane is imaged, the Imaged Volume Depth may be the optical depth of field as encoded in the Slice Thickness (0018,0050) attribute of the Pixel Measures Functional Group (see C.7.6.16.2.1.1).

C.8.12.4.1.3 Total Pixel Matrix Columns, Rows

Total Pixel Matrix Columns (0048,0006) and Total Pixel Matrix Rows (0048,0007) describe the size of the entire imaged volume as a single extent across all frames (tiles).

The extent would be as described in these attributes if the whole volume would be imaged and encoded as a non-sparse pixel matrix with the pixel spacing as specified in the Pixel Spacing (0028,0030) attribute of the Pixel Measures Functional Group (see C.7.6.16.2.1.1).

C.8.12.4.1.4 Total Pixel Matrix Origin Sequence and Image Orientation (Slide)

Total Pixel Matrix Origin Sequence (0048,0008) specifies the location of the top leftmost pixel of the pixel matrix, and Image Orientation (Slide) (0048,0102) specifies the direction cosines of the first row and the first column of the pixel matrix, both with respect to the Slide Coordinate System Frame of Reference (see C.8.12.2). Although the image acquisition may vary the true row and column orientation at the pixel scale to account for local variation in the physical specimen, this attribute describes the orientation as if the Pixel Matrix were flat.

Note: Typically, the Image Orientation (Slide) attribute will describe only a planar rotation, as the image plane is usually nominally parallel to the slide surface.

C.8.12.4.1.5 Photometric Interpretation and Samples per Pixel

Photometric Interpretation (0028,0004) shall be one of these Enumerated Values (see C.7.6.3.1.2):

MONOCHROME2

RGB

YBR_FULL_422

YBR_ICT

YBR_RCT

The value shall be appropriate to the compression transfer syntax used, if any, and shall be MONOCHROME2 or RGB for uncompressed or lossless compressed transfer syntaxes that do not involve color space transformations, YBR_ICT for irreversible JPEG 2000 transfer syntaxes, YBR_RCT for reversible JPEG 2000 transfer syntaxes, and YBR_FULL_422 for other lossy compressed transfer syntaxes.

Note: Future lossless and lossy transfer syntaxes may lead to the need for new definitions and choices for Photometric Interpretation. The Enumerated Values may therefore be extended with additional Photometric Interpretation values directly associated with new transfer syntaxes that are negotiated, and hence do not render existing implementations non-conformant.

Multi-spectral images may be encoded as a single wavelength band (color) in each frame using MONOCHROME2, or with up to three bands in each frame using one of the color Photometric Interpretations.

Samples per Pixel (0028,0002) shall be 1 for MONOCHROME2, and 3 otherwise.