| DICOM PS3.3 2024c - Information Object Definitions |
|---|
Table C.8.17.2-1 specifies the Attributes of the Ophthalmic Photography Image Module, which describe an Ophthalmic Photography Image produced by Ophthalmic Photography equipment (OP) imaging Modalities.
Table C.8.17.2-1. Ophthalmic Photography Image Module Attributes
|
Image identification characteristics. See Section C.8.17.2.1.4 for specialization. |
|||
|
Number of samples (planes) in this image. See Section C.8.17.2.1.2 for further explanation. |
|||
|
The number of samples (planes) containing information. |
|||
|
Indicates whether the pixel data are encoded color-by-plane or color-by-pixel. Required if Samples per Pixel (0028,0002) has a value greater than 1. |
|||
|
Nominal physical distance at the focal plane (in the retina) between the center of each pixel, specified by a numeric pair - adjacent row spacing (delimiter) adjacent column spacing in mm. See Section 10.7.1.3 for further explanation of the value order. NoteThese values are specified as nominal because the physical distance may vary across the field of the images and the lens correction is likely to be imperfect. Shall not be present when Two Dimensional to Three Dimensional Map Sequence (0022,1518) or X Coordinates Center Pixel View Angle (0022,1528) and Y Coordinates Center Pixel View Angle (0022,1529) are present. Otherwise, required when Acquisition Device Type Code Sequence (0022,0015) contains an Item with the value (409898007, SCT, "Fundus Camera"). May be present otherwise. |
|||
|
The date and time that the acquisition of data started. NoteThe synchronization of this time with an external clock is specified in the Synchronization Module in Acquisition Time Synchronized (0018,1800). Required if Image Type (0008,0008) Value 1 is ORIGINAL. May be present otherwise. |
|||
|
A Sequence that identifies the Images that were used to derive this Image. Required if Image Type (0008,0008) Value 1 is DERIVED. Zero or more Items shall be included in this Sequence. See Section C.12.4.1.2 for further explanation. |
|||
|
>Include Table 10-3 “Image SOP Instance Reference Macro Attributes” |
|||
|
Describes the purpose for which the reference is made, that is what role the source image or frame(s) played in the derivation of this image. |
|||
|
>>Include Table 8.8-1 “Code Sequence Macro Attributes”. |
|||
|
Specifies whether an Image has undergone lossy compression (at a point in its lifetime). Enumerated Values: Once this value has been set to "01" it shall not be reset. See Section C.7.6.1.1.5. |
|||
|
Describes the approximate lossy compression ratio(s) that have been applied to this image. |
|||
|
A label for the lossy compression method(s) that have been applied to this image. |
|||
|
Specifies an identity transformation for the Presentation LUT, such that the output of all grayscale transformations defined in the IOD containing this Module are defined to be P-Values. Required if Photometric Interpretation (0028,0004) is MONOCHROME2. |
|||
|
Indicates whether a reference object (phantom) of known size is present in the image and was used for calibration. |
|||
|
Indicates whether or not image contains sufficient burned in annotation to identify the patient and date the image was acquired. |
|||
|
Indicates whether or not the image contains sufficiently recognizable visual features to allow the image or a reconstruction from a set of images to identify the patient. If this Attribute is absent, then the image may or may not contain recognizable visual features. |
|||
The Referenced Image Sequence (0008,1140) in the General Image Module (Section C.7.6.1) shall not convey stereoscopic information, which instead shall be encoded using the Stereometric Relationship IOD.
Samples per Pixel (0028,0002) shall be 1 or 3.
Cameras producing 2-color images are required to use a value of 3 for Samples per Pixel (0028,0002) and a value of 2 for Samples per Pixel Used (0028,0003). For 2-color images with a RGB Photometric Interpretation, the R and G channel shall be used and the B channel shall have all values set to zero.
Specifies the intended interpretation of the pixel data.
When Samples per Pixel (0028,0002) is greater than 1, Photometric Interpretation (0028,0004) shall be RGB for uncompressed or lossless compressed Transfer Syntaxes that do not have defined color space transformations, YBR_ICT for irreversible JPEG 2000 Transfer Syntaxes, YBR_RCT for reversible JPEG 2000 Transfer Syntaxes, YBR_PARTIAL_420 for MPEG2, MPEG-4 AVC/H.264 and HEVC/H.265 Transfer Syntaxes and YBR_FULL_422 for JPEG lossy compressed Transfer Syntaxes.
The Image Type (0008,0008) Attribute (General Image Module, Section C.7.6.1) identifies important image characteristics in a multiple valued Data Element. For the Ophthalmic Photography Image IOD, Image Type is specified as a Type 1 Attribute and further specialized as follows:
Value 1 shall identify the Pixel Data Characteristics in accordance with Section C.7.6.1.1.2.
Value 2 shall identify the Patient Examination Characteristics in accordance with Section C.7.6.1.1.2.
Value 4 (optionally present) shall identify the type of test performed for image acquisition.
Defined Terms for Value 4:
a picture take at "green" illumination light; or just the green channel of a color sensor
a picture take at "red" illumination light; or just the red channel of a color sensor
a picture take at "blue" illumination light; or just the blue channel of a color sensor
fluorescein injected; a picture taken at fluorescein exciting illumination light; a filter passing just the emitted wavelength to sensor applied
Indocyanine green injected; a picture taken at Indocyanine green exciting illumination light; a filter passing just the emitted wavelength to sensor applied
A Montage Image is constructed out of several individual images, which also can be exchanged separately. The images used to create the montage image will be included in the Source Image Sequence (0008,2112) if those images are also exchanged. A Montage Image is identified as Image Type DERIVED\PRIMARY\MONTAGE
| DICOM PS3.3 2024c - Information Object Definitions |
|---|