Annex I (Normative) - DVD MPEG2 Interchange Profiles

I.1 Profile Identification

This Annex defines an Application Profile Class for all multi-frame Media Image Storage SOP Classes compressed with MPEG2.

Table I.1-1 STD-DVD-MPEG2-MPML and STD-DVD-SEC-MPEG2-MPML Profiles

Application Profile Identifier Description
DVD Interchange with MPEG2 MP@ML STD-DVD-MPEG2-MPML Handles interchange of multi-frame images as MPEG2 MP@ML compressed video sequences.
Secure DVD Interchange with MPEG2 MP@ML STD-DVD-SEC-MPEG2-MPML Handles interchange of multi-frame images as MPEG2 MP@ML compressed video sequences. Offers confidentiality, integrity and, depending on the File-set creator’s choice, data origin authentication.

Equipment claiming conformance to this Application Profile shall list the subset of Media Storage SOP Classes that it supports in its Conformance Statement.

I.2 Clinical Context

This Application Profile Class facilitates the interchange of images data on DVD media. Typical interchange would be between acquisition devices, archives and workstations.

I.2.1 Roles and Service Class Options

This Application Profile Class uses the Media Storage Service Class defined in PS3.4.

The Application Entity shall support one or more of the roles of File Set Creator (FSC) or File Set Reader (FSR), defined in PS 3.10. The File Set Updater (FSU) role is not defined.

I.2.1.1 File Set Creator

The role of File Set Creator shall be used by Application Entities that generate a File Set under this Image Interchange Class of Application Profiles.

File Set Creators shall be able to generate the Basic Directory SOP Class in the DICOMDIR file with all the subsidiary Directory Records related to the Image SOP Classes stored in the File Set. The Application Entity acting as a File Set Creator generates a File Set under a STD-DVD-MPEG2-MPML or STD-DVD-SEC-MPEG2-MPML Application Profile.

FSC shall offer the ability to either finalize the physical volume at the completion of the most recent write session (no additional information can be subsequently added to the volume) or to allow multi-session (additional information may be subsequently added to the volume). An FSC may allow packet-writing, if supported by the media and file system specified in the profile.

Note: A multiple volume (i.e. a logical volume that can cross multiple physical media) is not supported by this class of Application profile. If a set of Files, e.g., a Study, cannot be written entirely on one physical volume (side of one piece of media), the FSC will create multiple independent DICOM File Sets such that each File Set can reside on a single physical volume (side of a single piece of media) controlled by its individual DICOMDIR file. The user of the FSC can opt to use written labels on the physical volumes to indicate that there is more than one physical volume for this set of files (e.g., a study).

I.2.1.2 File Set Reader

The role of File Set Reader shall be used by Application Entities that receive a transferred File Set under the Image Interchange Class of Application Profiles. Typical entities using this role would include image generating systems, display workstations, and archive systems that receive a patient record; e.g. transferred from another institution.

File Set Readers shall be able to read the DICOMDIR directory file and all the SOP Instance files defined for this Application Profile, for which a Conformance Statement is made, using all the defined Transfer Syntaxes for the Profile.

I.2.1.3 File Set Updater

The FSU role is not defined for the STD-DVD-MPEG2-MPML and STD-DVD-SEC-MPEG2-MPML profiles.

I.3 STD-DVD-MPEG2-MPML and STD-DVD-SEC-MPEG2-MPML Profile ClassES

I.3.1 SOP Classes and Transfer Syntaxes

This Application Profile is based on the Media Storage Service Class (see PS 3.4).

Table I.3-1STD-DVD-MPEG2-MPML and STD-DVD-SEC-MPEG2-MPML SOP Classes and Transfer Syntaxes

Information Object Definition Service Object Pair Class UID Transfer Syntax and UID FSC Requirement FSR Requirement
Basic Directory 1.2.840.10008.1.3.10 Explicit VR Little Endian Uncompressed 1.2.840.10008.1.2.1 Mandatory Mandatory
Multi-frame Composite IODs for which a Media Storage SOP Class is defined in PS 3.4 See PS 3.4 MPEG2 MP@ML Image Compression 1.2.840.10008.1.2.4.100 Defined in Conformance Statement Mandatory for all SOP Classes defined in Conformance Statement
The SOP Classes and corresponding Transfer Syntax supported by this Application Profile are specified in the Table I.3-1. The supported Storage SOP Class(es) shall be listed in the Conformance Statement using a table of the same form.

I.3.2 Physical Medium And Medium Format

The STD-DVD-MPEG2-MPML and STD-DVD-SEC-MPEG2-MPML application profiles require any of the 120 mm DVD media other than DVD-RAM, as defined in PS 3.12.

I.3.3 Directory Information in DICOMDIR

Conformant Application Entities shall include in the DICOMDIR File the Basic Directory IOD containing Directory Records at the Patient and the subsidiary Study and Series levels, appropriate to the SOP Classes in the File Set.

All DICOM files in the File Set incorporating SOP Instances defined for the specific Application Profile shall be referenced by Directory Records.

Note: DICOMDIRs with no directory information are not allowed by this Application Profile.

All implementations shall include the DICOM Media Storage Directory in the DICOMDIR file. There shall only be one DICOMDIR file per File Set. The DICOMDIR file shall be in the root directory of the medium. The Patient ID at the patient level shall be unique for each patient directory record in one File Set.

I.3.3.1 Additional Keys

File Set Creators and Updaters are required to generate the mandatory elements specified in PS 3.3.

Table I.3-2 specifies the additional associated keys. At each directory record level other additional data elements can be added, but it is not required that File Set Readers be able to use them as keys. Refer to the Basic Directory IOD in PS 3.3.

Table I.3-2STD-DVD-MPEG2-MPML and STD-DVD-SEC-MPEG2-MPML Additional DICOMDIR Keys

Key Attribute Tag Directory Record Type Type Notes
Patient’s Birth Date (0010,0030) PATIENT 1C Required if present in any objects referenced by subordinate records with a non-zero length value.
Patient’s Sex (0010,0040) PATIENT 1C Required if present in any objects referenced by subordinate records with a non-zero length value.
Institution Name (0008,0080) SERIES 1C Required if present in any objects referenced by subordinate records with a non-zero length value.
Institution Address (0008,0081) SERIES 1C Required if present in any objects referenced by subordinate records with a non-zero length value.
Performing Physicians’ Name (0008,1050) SERIES 1C Required if present in any objects referenced by subordinate records with a non-zero length value.
Image Type (0008,0008) IMAGE 1C Required if present in image object.
Lossy Image Compression Ratio (0028,2112) IMAGE 1C Required if present in image object with a non-zero length value.
Rows (0028,0010) IMAGE 1
Columns (0028,0011) IMAGE 1

Note: The requirements with respect to the mandatory DICOMDIR keys in PS 3.3 imply that either these attributes are present in the Image IOD, or they are in some other way supplied by the File-set Creator. These attributes are (0010,0020) Patient ID, (0008,0020) Study Date, (0008,0030) Study Time, (0020,0010) Study ID, (0020,0011) Series Number, and (0020,0013) Instance Number.

I.3.4 Security Parameters

The STD-DVD-SEC-MPEG2-MPML application profiles require that all DICOM Files in the File-set including the DICOMDIR be Secure DICOM Files encapsulated in accordance with the requirements of the Basic DICOM Media Security Profile as defined in PS 3.15.

Note: These Application Profiles do not place any consistency restrictions on the use of the Basic DICOM Media Security Profile with different DICOM Files of one File-set. For example, readers should not assume that all Files in the File-set can be decoded by the same set of recipients. Readers should also not assume that all secure Files use the same approach (hash key or digital signature) to ensure Integrity or carry the same originators’ signatures.

I.3.5 “Dual-format” (Informative)

It is desirable that consumer DVD players (and computer software for playing conventional DVD movies) be able to play the video data that is encoded on the DICOM DVD. The MPEG2 bit stream that is “encapsulated” by the DICOM Transfer Syntax is potentially re-usable by such applications, if the appropriate UDF structure is created to share the same extent between the DICOM file and the file format and folder structure used by the consumer DVD Video format. Alternatively, the bit stream could be duplicated and both sets of files present on the same piece of media.

This profile does not require this, nor specify which approach to take. Specifically, this profile does not require that a DVD Video file and folder structure be present, though it is recommended.