Computed Radiography ImageCIOD
CT ImageCIOD
MR ImageCIOD
Nuclear Medicine ImageCIOD
Ultrasound ImageCIOD
Ultrasound Multi-frame ImageCIOD
Secondary Capture ImageCIOD
Multi-frame Single Bit Secondary Capture ImageCIOD
Multi-frame Grayscale Byte Secondary Capture ImageCIOD
Multi-frame Grayscale Word Secondary Capture ImageCIOD
Multi-frame True Color Secondary Capture ImageCIOD
X-Ray Angiographic ImageCIOD
X-Ray Radiofluoroscopic ImageCIOD
RT ImageCIOD
RT DoseCIOD
RT Structure SetCIOD
RT PlanCIOD
Positron Emission Tomography ImageCIOD
Digital X-Ray ImageCIOD
Digital Mammography X-Ray ImageCIOD
Digital Intra-Oral X-Ray ImageCIOD
RT Beams Treatment RecordCIOD
RT Brachy Treatment RecordCIOD
RT Treatment Summary RecordCIOD
VL Endoscopic ImageCIOD
VL Microscopic ImageCIOD
VL Slide-Coordinates Microscopic ImageCIOD
VL Photographic ImageCIOD
Video Endoscopic ImageCIOD
Video Microscopic ImageCIOD
Video Photographic ImageCIOD
VL Whole Slide Microscopy ImageCIOD
Real-Time Video Endoscopic ImageCIOD
Real-Time Video Photographic ImageCIOD
Dermoscopic Photography ImageCIOD
Grayscale Softcopy Presentation StateCIOD
Color Softcopy Presentation StateCIOD
Pseudo-Color Softcopy Presentation StateCIOD
Blending Softcopy Presentation StateCIOD
Basic Structured DisplayCIOD
XA/XRF Grayscale Softcopy Presentation StateCIOD
Advanced Blending Presentation StateCIOD
Variable Modality LUT Softcopy Presentation StateCIOD
Basic Voice Audio WaveformCIOD
12-Lead ECGCIOD
General ECGCIOD
Ambulatory ECGCIOD
Hemodynamic WaveformCIOD
Basic Cardiac Electrophysiology WaveformCIOD
Arterial Pulse WaveformCIOD
Respiratory WaveformCIOD
General Audio WaveformCIOD
Real-Time Audio WaveformCIOD
Routine Scalp ElectroencephalogramCIOD
ElectromyogramCIOD
ElectrooculogramCIOD
Sleep ElectroencephalogramCIOD
Multi-channel Respiratory WaveformCIOD
Body Position WaveformCIOD
General 32-bit ECGCIOD
Basic Text SRCIOD
Enhanced SRCIOD
Comprehensive SRCIOD
Key Object Selection DocumentCIOD
Mammography CAD SRCIOD
Chest CAD SRCIOD
Procedure LogCIOD
X-Ray Radiation Dose SRCIOD
Spectacle Prescription ReportCIOD
Colon CAD SRCIOD
Macular Grid Thickness and Volume ReportCIOD
Implantation Plan SR DocumentCIOD
Comprehensive 3D SRCIOD
Radiopharmaceutical Radiation Dose SRCIOD
Extensible SRCIOD
Acquisition Context SRCIOD
Simplified Adult Echo SRCIOD
Patient Radiation Dose SRCIOD
Planned Imaging Agent Administration SRCIOD
Performed Imaging Agent Administration SRCIOD
Rendition Selection DocumentCIOD
Enhanced X-Ray Radiation Dose SRCIOD
Enhanced MR ImageCIOD
MR SpectroscopyCIOD
Enhanced MR Color ImageCIOD
Raw DataCIOD
Enhanced CT ImageCIOD
Spatial RegistrationCIOD
Deformable Spatial RegistrationCIOD
Spatial FiducialsCIOD
Ophthalmic Photography 8 Bit ImageCIOD
Ophthalmic Photography 16 Bit ImageCIOD
Stereometric RelationshipCIOD
Hanging ProtocolCIOD
Encapsulated PDFCIOD
Encapsulated CDACIOD
Real World Value MappingCIOD
Enhanced XA ImageCIOD
Enhanced XRF ImageCIOD
RT Ion PlanCIOD
RT Ion Beams Treatment RecordCIOD
SegmentationCIOD
Ophthalmic Tomography ImageCIOD
X-Ray 3D Angiographic ImageCIOD
PatientMModule - Patient
(0008,1120) Referenced Patient Sequence3Sequence
(0010,0010) Patient's Name2Person Name
(0010,0020) Patient ID2Long String
(0010,0021) Issuer of Patient ID3Long String
(0010,0022) Type of Patient ID3Code String
(0010,0024) Issuer of Patient ID Qualifiers Sequence3Sequence
(0010,0026) Source Patient Group Identification Sequence3Sequence
(0010,0027) Group of Patients Identification Sequence3Sequence
(0010,0030) Patient's Birth Date2Date
(0010,0032) Patient's Birth Time3Time
(0010,0033) Patient's Birth Date in Alternative Calendar3Long String
(0010,0034) Patient's Death Date in Alternative Calendar3Long String
(0010,0035) Patient's Alternative Calendar1CCode String
(0010,0040) Patient's Sex2Code String
(0010,0200) Quality Control Subject3Code String
(0010,0212) Strain Description3Unlimited Characters
(0010,0213) Strain Nomenclature3Long String
(0010,0216) Strain Stock Sequence3Sequence
(0010,0218) Strain Additional Information3Unlimited Text
(0010,0219) Strain Code Sequence3Sequence
(0010,0221) Genetic Modifications Sequence3Sequence
(0010,1001) Other Patient Names3Person Name
(0010,1002) Other Patient IDs Sequence3Sequence
(0010,1100) Referenced Patient Photo Sequence3Sequence
(0010,2160) Ethnic Group3Short String
(0010,2201) Patient Species Description1CLong String
(0010,2202) Patient Species Code Sequence1CSequence
(0010,2292) Patient Breed Description2CLong String
(0010,2293) Patient Breed Code Sequence2CSequence
(0010,2294) Breed Registration Sequence2CSequence
(0010,2297) Responsible Person2CPerson Name
(0010,2298) Responsible Person Role1CCode String
(0010,2299) Responsible Organization2CLong String
(0010,4000) Patient Comments3Long Text
(0012,0062) Patient Identity Removed3Code String
(0012,0063) De-identification Method1CLong String
(0012,0064) De-identification Method Code Sequence1CSequence
Clinical Trial SubjectUModule - Patient
General StudyMModule - Study
Patient StudyUModule - Study
Clinical Trial StudyUModule - Study
General SeriesMModule - Series
Clinical Trial SeriesUModule - Series
Enhanced SeriesMModule - Series
Frame of ReferenceMModule - Frame of Reference
SynchronizationUModule - Frame of Reference
General EquipmentMModule - Equipment
Enhanced General EquipmentMModule - Equipment
Image PixelMModule - Image
Enhanced Contrast/BolusCModule - Image
DeviceUModule - Image
InterventionUModule - Image
Acquisition ContextMModule - Image
Multi-frame Functional GroupsMModule - Image
Multi-frame DimensionUModule - Image
Cardiac SynchronizationCModule - Image
Respiratory SynchronizationCModule - Image
Patient OrientationUModule - Image
Image - Equipment Coordinate RelationshipUModule - Image
SpecimenUModule - Image
X-Ray 3D ImageMModule - Image
X-Ray 3D Angiographic Image Contributing SourcesUModule - Image
X-Ray 3D Angiographic AcquisitionUModule - Image
X-Ray 3D ReconstructionUModule - Image
SOP CommonMModule - Image
Common Instance ReferenceUModule - Image
Frame ExtractionCModule - Image
X-Ray 3D Craniofacial ImageCIOD
Breast Tomosynthesis ImageCIOD
Enhanced PET ImageCIOD
Surface SegmentationCIOD
Color PaletteCIOD
Enhanced US VolumeCIOD
Lensometry MeasurementsCIOD
Autorefraction MeasurementsCIOD
Keratometry MeasurementsCIOD
Subjective Refraction MeasurementsCIOD
Visual Acuity MeasurementsCIOD
Ophthalmic Axial MeasurementsCIOD
Intraocular Lens CalculationsCIOD
Generic Implant TemplateCIOD
Implant Assembly TemplateCIOD
Implant Template GroupCIOD
RT Beams Delivery InstructionCIOD
Ophthalmic Visual Field Static Perimetry MeasurementsCIOD
Intravascular Optical Coherence Tomography ImageCIOD
Ophthalmic Thickness MapCIOD
Surface Scan MeshCIOD
Surface Scan Point CloudCIOD
Legacy Converted Enhanced CT ImageCIOD
Legacy Converted Enhanced MR ImageCIOD
Legacy Converted Enhanced PET ImageCIOD
Corneal Topography MapCIOD
Breast Projection X-Ray ImageCIOD
Parametric MapCIOD
Wide Field Ophthalmic Photography Stereographic Projection ImageCIOD
Wide Field Ophthalmic Photography 3D Coordinates ImageCIOD
Tractography ResultsCIOD
RT Brachy Application Setup Delivery InstructionCIOD
Planar MPR Volumetric Presentation StateCIOD
Volume Rendering Volumetric Presentation StateCIOD
Content Assessment ResultsCIOD
CT Performed Procedure ProtocolCIOD
CT Defined Procedure ProtocolCIOD
Protocol ApprovalCIOD
XA Performed Procedure ProtocolCIOD
XA Defined Procedure ProtocolCIOD
Ophthalmic Optical Coherence Tomography En Face ImageCIOD
Ophthalmic Optical Coherence Tomography B-scan Volume AnalysisCIOD
Encapsulated STLCIOD
Encapsulated OBJCIOD
Encapsulated MTLCIOD
RT Physician IntentCIOD
RT Segment AnnotationCIOD
RT Radiation SetCIOD
C-Arm Photon-Electron RadiationCIOD
Tomotherapeutic RadiationCIOD
Robotic-Arm RadiationCIOD
RT Radiation Record SetCIOD
RT Radiation Salvage RecordCIOD
C-Arm Photon-Electron Radiation RecordCIOD
Tomotherapeutic Radiation RecordCIOD
Robotic-Arm Radiation RecordCIOD
RT Radiation Set Delivery InstructionCIOD
RT Treatment PreparationCIOD
Enhanced RT ImageCIOD
Enhanced Continuous RT ImageCIOD
RT Patient Position Acquisition InstructionCIOD
Microscopy Bulk Simple AnnotationsCIOD
InventoryCIOD
Photoacoustic ImageCIOD
Confocal Microscopy ImageCIOD
Confocal Microscopy Tiled Pyramidal ImageCIOD
Basic DirectoryCIOD

Built with by Innolitics, a team of medical imaging software developers.

Data synced with official DICOM standard on 18 April 2024. The DICOM Standard is under continuous maintenance, and the current official version is available at http://www.dicomstandard.org/current/. DICOM Parts 3, 4, and 6, © NEMA. Please note that the most recent PDF version of the standard is the official reference, and should checked when making technical decisions.

Quality Control Subject Attribute

Tag(0010,0200)
TypeOptional (3)
KeywordQualityControlSubject
Value Multiplicity1
Value RepresentationCode String (CS)

Indicates whether or not the subject is a quality control phantom.

Enumerated Values:

YES

NO

If this Attribute is absent, then the subject may or may not be a phantom.

This Attribute describes a characteristic of the Imaging Subject. It is distinct from Quality Control Image (0028,0300) in the General Image Module, which is used to describe an image acquired.

General Image Module

C.7.6.1 General Image Module

Table C.7-9 specifies the Attributes of the General Image Module, which identify and describe an image within a particular Series.

Table C.7-9. General Image Module Attributes

Attribute Name

Tag

Type

Attribute Description

Instance Number

(0020,0013)

2

A number that identifies this image.

Note

This Attribute was named Image Number in earlier versions of this Standard.

Patient Orientation

(0020,0020)

2C

Patient direction of the rows and columns of the image. Required if image does not require Image Orientation (Patient) (0020,0037) and Image Position (Patient) (0020,0032) or if image does not require Image Orientation (Slide) (0048,0102). May be present otherwise. See Section C.7.6.1.1.1 for further explanation.

Note

IODs may have Attributes other than Patient Orientation, Image Orientation, or Image Position (Patient) to describe orientation in which case this Attribute will be zero length.

Content Date

(0008,0023)

2C

The date the image pixel data creation started.

Required if image is part of a Series in which the images are temporally related. May be present otherwise.

Note

This Attribute was formerly known as Image Date.

Content Time

(0008,0033)

2C

The time the image pixel data creation started.

Required if image is part of a Series in which the images are temporally related. May be present otherwise.

Image Type

(0008,0008)

3

Image identification characteristics. See Section C.7.6.1.1.2 for Defined Terms and further explanation.

Image Comments

(0020,4000)

3

User-defined comments about the image.

Quality Control Image

(0028,0300)

3

Indicates whether or not quality control material (such as calibration or control material, or a phantom) is present in this image.

Enumerated Values:

YES

the image contains only quality control material

NO

the image does not contain quality control material

BOTH

the image contains both subject (patient) and quality control information

If this Attribute is absent, then the image may or may not be a quality control or phantom image. The phantom device or quality control material in the image can be described using the Device Module. See Section C.7.6.12.

Note

Examples of the presence of both subject and quality control information include:

  • presence of objects of known density in radiographic images for calibration

  • presence of control material for immunohistochemistry within slide images

Burned In Annotation

(0028,0301)

3

Indicates whether or not image contains sufficient burned in annotation to identify the patient and date the image was acquired.

Enumerated Values:

YES

NO

If this Attribute is absent, then the image may or may not contain burned in annotation.

Recognizable Visual Features

(0028,0302)

3

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.

Enumerated Values:

YES

NO

If this Attribute is absent, then the image may or may not contain recognizable visual features.

Lossy Image Compression

(0028,2110)

3

Specifies whether an Image has undergone lossy compression (at a point in its lifetime).

Enumerated Values:

00

Image has not been subjected to lossy compression.

01

Image has been subjected to lossy compression.

Once this value has been set to "01" it shall not be reset.

See Section C.7.6.1.1.5.

Lossy Image Compression Ratio

(0028,2112)

3

Describes the approximate lossy compression ratio(s) that have been applied to this image.

See Section C.7.6.1.1.5.2.

Lossy Image Compression Method

(0028,2114)

3

A label for the lossy compression method(s) that have been applied to this image.

See Section C.7.6.1.1.5.1.

Icon Image Sequence

(0088,0200)

3

This icon image is representative of the Image.

Only a single Item is permitted in this Sequence.

>Include Table C.7-11b “Image Pixel Macro Attributes”

See Section C.7.6.1.1.6 for further explanation.

Presentation LUT Shape

(2050,0020)

3

When present, specifies an identity transformation for the Presentation LUT such that the output of all grayscale transformations, if any, are defined to be in P-Values.

Enumerated Values:

IDENTITY

output is in P-Values - shall be used if Photometric Interpretation (0028,0004) is MONOCHROME2 or any color photometric interpretation.

INVERSE

output after inversion is in P-Values - shall be used if Photometric Interpretation (0028,0004) is MONOCHROME1.

When this Attribute is used with a color photometric interpretation then the luminance component is in P-Values.

Real World Value Mapping Sequence

(0040,9096)

3

The mapping of stored values to associated Real World values.

One or more Items are permitted in this Sequence.

>Include Table C.7.6.16-12b “Real World Value Mapping Item Macro Attributes”

Image Laterality

(0020,0062)

3

Laterality of (possibly paired) body part (as described in Anatomic Region Sequence (0008,2218)) examined.

Enumerated Values:

R

right

L

left

U

unpaired

B

both left and right

Shall be consistent with any laterality information contained in Primary Anatomic Structure Modifier Sequence (0008,2230) and/or Laterality (0020,0060), if present.

Note

Laterality (0020,0060) is a Series level Attribute and must be the same for all Images in the Series, hence it must be absent if Image Laterality (0020,0062) has different values for Images in the same Series.

Include Table 10-7 “General Anatomy Optional Macro Attributes”

Anatomic Region Sequence BCID 4031 “Common Anatomic Region” for humans.

Anatomic Region Sequence BCID 7483 “Common Anatomic Regions for Animal” for non-human organisms.


Note

Previous releases of this Standard specified use of the Referenced Waveform Sequence (0008,113A), but that use has been superseded by Referenced Instance Sequence (0008,114A). See PS3.3-2004.

C.7.6.1.1 General Image Module Attribute Descriptions
C.7.6.1.1.1 Patient Orientation

Patient Orientation (0020,0020) relative to the image plane shall be specified by two values that designate the anatomical direction of the positive row axis (left to right) and the positive column axis (top to bottom). The first entry is the direction of the rows, given by the direction of the last pixel in the first row from the first pixel in that row. The second entry is the direction of the columns, given by the direction of the last pixel in the first column from the first pixel in that column. Shall be consistent with Image Orientation (Patient) (0020,0037), if both Attributes are present and Patient Orientation (0020,0020) is not zero length.

If Anatomical Orientation Type (0010,2210) is absent or has a value of BIPED, anatomical direction shall be designated by abbreviations using the capital letters:

  • A (anterior)

  • P (posterior)

  • R (right)

  • L (left)

  • H (head)

  • F (foot)

If Anatomical Orientation Type (0010,2210) has a value of QUADRUPED, anatomical direction shall be designated by the abbreviations using capital letters:

  • LE (Le or Left)

  • RT (Rt or Right)

  • D (Dorsal)

  • V (Ventral)

  • CR (Cr or Cranial)

  • CD (Cd or Caudal)

  • R (Rostral)

  • M (Medial)

  • L (Lateral)

  • PR (Pr or Proximal)

  • DI (Di or Distal)

  • PA (Pa or Palmar)

  • PL (Pl or Plantar)

Note

  1. These abbreviations are capitalized versions of those defined in Smallwood et al for describing radiographic projections. Because of the Code String (CS) Value Representation of Patient Orientation (0020,0020), lowercase letters cannot be used.

  2. It is unfortunate that the conventional veterinary abbreviations (e.g., R for rostral and Rt for right) differ from those chosen for humans for DICOM usage (e.g., R for right), but confusion with in the respective human and non-human organism domains will be reduced. Hanging protocols may need to account for the difference by checking for the correct species.

  3. Smallwood et al define an O (Oblique) abbreviation, which is useful for describing radiographic projections, but do not specify its use for directional terms, and hence it is not included here for describing the row and column directions.

  4. The terms "anterior" and "posterior" are commonly used in vertebrate zoology to describe the cranial and caudal directions respectively, the veterinary terms are used in preference here, also in order to avoid confusion with the contradictory human use of anterior and posterior to mean ventral and dorsal.

  5. For non-human organisms other than quadrupeds, for example, birds and fish, it is anticipated that the same nomenclature can be logically extended to describe, for example, wings and fins.

Each value of the orientation Attribute shall contain at least one of these abbreviations. If refinements in the orientation descriptions are to be specified, then they shall be designated by one or two additional abbreviations in each value. Within each value, the abbreviations shall be ordered with the principal orientation designated in the first abbreviations.

Note

  1. For bipeds, since each abbreviation is a single character, no delimiter is required within a single value and none is used. For quadrupeds, though lowercase letters cannot be used, delimiters are not necessary within a single value to eliminate ambiguity, since the abbreviations used are sufficiently distinct, and can be parsed from left to right with a single character of lookahead.

  2. E.g., a medio-lateral oblique projection of the left breast of a human might be encoded with Patient Orientation values of "A\FR" rather than "A\F", since the plane is obliquely inclined such that the columns are directed both downwards and medially, which for a left breast is towards the right, though the downwards direction is the principal column orientation.

  3. E.g., a right dorsal-left ventral oblique view of a quadruped's abdomen might be encoded with Patient Orientation values of "LEV\CD", rather than "LE\CD", since the plane is obliquely inclined such that the rows are directed both to the left and ventrally, though the left direction is the principal row orientation. The abbreviations "LEV", "LE" and "CD", correspond to the designations in Smallwood et al of "LeV", "Le" and "Cd", respectively

C.7.6.1.1.2 Image Type

Image Type (0008,0008) identifies important image identification characteristics. These characteristics are:

  1. Pixel Data Characteristics

    1. is the image an ORIGINAL Image; an image whose pixel values are based on original or source data

    2. is the image a DERIVED Image; an image whose pixel values have been derived in some manner from the pixel value of one or more other images

  2. Patient Examination Characteristics

    1. is the image a PRIMARY Image; an image created as a direct result of the patient examination

    2. is the image a SECONDARY Image; an image created after the initial patient examination

  3. Modality Specific Characteristics

  4. Implementation specific identifiers; other implementation specific identifiers shall be documented in an implementation's conformance statement.

The Image Type Attribute is multi-valued and shall be provided in the following manner:

  1. Value 1 shall identify the Pixel Data Characteristics

    Enumerated Values:

    ORIGINAL

    identifies an Original Image

    DERIVED

    identifies a Derived Image

  2. Value 2 shall identify the Patient Examination Characteristics

    Enumerated Values:

    PRIMARY

    identifies a Primary Image

    SECONDARY

    identifies a Secondary Image

  3. Value 3 shall identify any Image IOD specific specialization (optional)

  4. Other Values that are implementation specific (optional)

Any of the optional values (value 3 and beyond) may be encoded either with a value or zero-length, independent of other optional values, unless otherwise specified by a specialization of this Attribute in an IOD.

If the pixel data of the derived Image is different from the pixel data of the source images and this difference is expected to affect professional interpretation of the image, the Derived Image shall have a UID different than all the source images.

C.7.6.1.1.3 Derivation Description

See Section C.12.4.1.1.

C.7.6.1.1.4 Source Image Sequence

Source Image Sequence (0008,2112) was formerly used in this Module but has been moved to the General Reference Module. See Section C.12.4.1.2 “Source Image Sequence”.

C.7.6.1.1.5 Lossy Image Compression

The Attribute Lossy Image Compression (0028,2110) conveys that the Image has undergone lossy compression. It provides a means to record that the Image has been compressed (at a point in its lifetime) with a lossy algorithm and changes have been introduced into the pixel data. Once the value has been set to "01", it shall not be reset.

Note

If an image is compressed with a lossy algorithm, the Attribute Lossy Image Compression (0028,2110) is set to "01". Subsequently, if the image is decompressed and transferred in uncompressed format, this Attribute value remains "01".

The value of Lossy Image Compression (0028,2110) in SOP Instances containing multiple frames in which one or more of the frames have undergone lossy compression shall be "01".

Note

It is recommended that the applicable frames be noted in the Attribute Derivation Description (0008,2111).

If an image is originally obtained as a lossy compressed image from the sensor, then Lossy Image Compression (0028,2110) is set to "01" and Value 1 of the Attribute Image Type (0008,0008) shall be set to ORIGINAL.

If an image is a compressed version of another image, Lossy Image Compression (0028,2110) is set to "01", Value 1 of the Attribute Image Type (0008,0008) shall be set to DERIVED, and if the predecessor was a DICOM image, then the Image shall receive a new SOP Instance UID.

Note

  1. It is recommended that the approximate compression ratio be provided in the Attribute Derivation Description (0008,2111). Furthermore, it is recommended that Derivation Description (0008,2111) be used to indicate when pixel data changes might affect professional interpretation (see Section C.12.4.1.1).

  2. The Attribute Lossy Image Compression (0028,2110) is defined as Type 3 for backward compatibility with existing IODs. It is expected to be required (i.e., defined as Type 1C) for new Image IODs and for existing IODs that undergo a major revision (e.g., a new IOD is specified).

C.7.6.1.1.5.1 Lossy Image Compression Method

Lossy Image Compression Method (0028,2114) may be multi-valued if successive lossy compression steps have been applied; the value order shall correspond to the values of Lossy Image Compression Ratio (0028,2112), if present.

Defined Terms for Lossy Image Compression Method (0028,2114):

ISO_10918_1

JPEG Lossy Compression [ISO/IEC 10918-1]

ISO_14495_1

JPEG-LS Near-lossless Compression [ISO/IEC 14495-1]

ISO_15444_1

JPEG 2000 Irreversible Compression [ISO/IEC 15444-1]

ISO_15444_15

High-Throughput JPEG 2000 Irreversible Compression [ISO/IEC 15444-15]

ISO_13818_2

MPEG2 Compression [ISO/IEC 13818-2]

ISO_14496_10

MPEG-4 AVC/H.264 Compression [ISO/IEC 14496-10]

ISO_23008_2

HEVC/H.265 Lossy Compression [ISO/IEC 23008-2]

C.7.6.1.1.5.2 Lossy Image Compression Ratio

The value of the "compression ratio" is encoded as a numeric value that represents the numerator of an implicit ratio in which the denominator is always one, consistent with the traditional representation in the literature.

Note

For example, a compression ratio of 30:1 would be described with a value of 30.

The value may be an estimate (e.g., the nominal value that is supplied to the compressor), or it may be a measured value (e.g., computed by dividing the uncompressed pixel data size by the size of the compressed bit stream).

Lossy Image Compression Ratio (0028,2112) may be multi-valued if successive lossy compression steps have been applied; if so, the value order shall correspond to the multiple values of Lossy Image Compression Method (0028,2114), if present.

Note

For historical reasons, the lossy compression ratio should also be described in Derivation Description (0008,2111).

C.7.6.1.1.6 Icon Image Sequence

An Icon Image may be used as a key representative of an Image. It is defined as a Sequence that contains a single Item encapsulating the Data Set made of the Data Elements of the Icon Image. The Data Elements are defined by the Section C.7.6.3.2 Image Pixel Macro. Unless otherwise specified in the Module or Macro table where the Icon Image Sequence (0088,0200) is used, the following restrictions shall apply on the Image Pixel Macro usage:

  1. Only monochrome and palette color images shall be used. Samples per Pixel (0028,0002) shall have a Value of 1, Photometric Interpretation (0028,0004) shall have a Value of either MONOCHROME 1, MONOCHROME 2 or PALETTE COLOR, Planar Configuration (0028,0006) shall not be present.

    Note

    True color icon images are not supported. This is due to the fact that the reduced size of the Icon Image makes the quality of a palette color image (with 256 colors) sufficient in most cases.

  2. There is no explicit limitation on the size of an Icon Image specified by Rows (0028,0010) and Columns (0028,0011).

  3. Pixel samples shall have a Value of either 1 or 8 for Bits Allocated (0028,0100) and Bits Stored (0028,0101). High Bit (0028,0102) shall have a Value of one less than the Value used in Bit Stored.

  4. Pixel Representation (0028,0103) shall specify an unsigned integer representation (Value 0000H).

  5. the pixels shall be square (i.e., their aspect ratio shall be 1:1) and therefore Pixel Aspect Ratio (0028,0034) shall not be present.

  6. If a Palette Color lookup Table is used, Bits Allocated (0028,0100) shall have a Value of 8.

C.7.6.1.1.7 Irradiation Event UID

See Section C.7.10.1.1.1.