pynetdicom.pdu_items.SOPClassExtendedNegotiationSubItem

class pynetdicom.pdu_items.SOPClassExtendedNegotiationSubItem

A SOP Class Extended Negotiation Sub-item.

A SOP Class Extended Negotation Sub-item allows peer Application Entities to exchange application information defined by specific Service Class specifications 1.

item_length

The number of bytes from the first byte following the Item Length field to the last byte of the Item.

Type

int

item_type

The Item Type field value (0x56).

Type

int

service_class_application_information

The Service Class Application Information field value.

Type

bytes

sop_class_uid

The SOP Class UID field value.

Type

uid

sop_class_uid_length

The SOP Class UID Length field value.

Type

int

Notes

A SOP Class Extended Negotiation Sub-item requires the following parameters:

• Item type (1, fixed, 0x56)

• Item length (1)

• SOP Class UID length (1)

• SOP Class UID (1)

• Service class application information

Encoding

When encoded, a SOP Class Extended Negotiation Sub-item has the following structure, taken from Table D.3-11 1 (offsets shown with Python indexing). Items are always encoded using Big Endian 2. The SOP Class UID parameter is encoded as a UID as per the rules in Part 5, Section 9.1 (ie NO trailing padding null byte).

Offset	Length	Description
0	1	Item type
1	1	Reserved
2	2	Item length
4	2	SOP class UID length
6	Variable	SOP class UID
6 + UID length	Variable	Service class application info

References

1(1,2)

DICOM Standard, Part 7, Annex D.3.3.5

2

DICOM Standard, Part 8, Section 9.3.1

__init__()

Initialise a new SOP Class Extended Negotiation Item.

Methods

__init__()	Initialise a new SOP Class Extended Negotiation Item.
decode(bytestream)	Decode bytestream and use the result to set the field values of the PDU item.
encode()	Return the encoded PDU as bytes.
from_primitive(primitive)	Set the item's values using a SOP Class Extended Negotiation primitive.
to_primitive()	Return a SOP Class Extended Negotiation primitive from the current Item.

Attributes

app_info	Return the item's Service Class Application Information field value.
item_length	Return the item's Item Length field value as an int.
item_type	Return the item's Item Type field value as an int.
sop_class_uid	Return the item's SOP Class UID field value.
sop_class_uid_length	Return the item's SOP Class UID Length field value.
uid	Return the item's SOP Class UID field value.