pynetdicom.pdu_items.PresentationContextItemAC¶

class pynetdicom.pdu_items.PresentationContextItemAC[source]¶

A Presentation Context (AC) Ttem.

Presentation Contexts (AC) Items are used by the association acceptor to signal which Abstract Syntaxes and Transfer Syntaxes have been accepted or rejected.

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 (0x21).

Type: int

presentation_context_id¶

The Presentation Context ID field value, an odd integer between 1 and 255.

Type: int or None

result_reason¶

The Presentation Context’s Result/reason field value.

Type: int

transfer_syntax¶

The Presentation Context Item’s Transfer Syntax (if available).

Type: list of pydicom.uid.UID

transfer_syntax_sub_item¶

The Presentation Context Items’ Transfer Syntax Sub-item field value.

Type: list of pynetdicom.uid.UID

Notes

A Presentation Context (AC) Item requires the following parameters:

Item type (1, fixed value, 0x21)

Item length (1)

Presentation context ID (1)

Result/reason (1)

Transfer Syntax Sub-item (1)

Item type (1, fixed, 0x40)

Item length (1)

Transfer syntax name (1)

Encoding

When encoded, a Presentation Context (AC) Item has the following structure, taken from Part 8, Table 9-13 of the DICOM Standard (offsets shown with Python indexing). Items are always encoded using Big Endian.

Offset	Length	Description
0	1	Item type
1	1	Reserved
2	2	Item length
4	1	Presentation context ID
5	1	Reserved
6	1	Result/reason
7	1	Reserved
8	Variable	Transfer syntax sub-item

References

DICOM Standard, Part 8, Section 9.3.3.2
DICOM Standard, Part 8, Section 9.3.1

__init__()[source]¶: Initialise a new Presentation Context (AC) Item.

Methods

`__init__`()	Initialise a new Presentation Context (AC) 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 Presentation Context primitive.
`to_primitive`()	Return a PresentationContext primitive from the current Item.

Attributes

`context_id`	Return the item’s Presentation Context ID field value.
`item_length`	Return the item’s Item Length field value as `int`.
`item_type`	Return the item’s Item Type field value as `int`.
`result`	Return the item’s Result/reason field value.
`result_str`	Get a string describing the result.
`transfer_syntax`	Return the Transfer Syntax, if available.

property context_id¶: Return the item’s Presentation Context ID field value.

from_primitive(primitive)[source]¶

Set the item’s values using a Presentation Context primitive.

Parameters: primitive (presentation.PresentationContext) – The primitive to use to set the Item’s field values.

property item_length¶: Return the item’s Item Length field value as int.

property result¶: Return the item’s Result/reason field value.

property result_str¶: Get a string describing the result.

to_primitive()[source]¶

Return a PresentationContext primitive from the current Item.

Returns: The primitive representation of the current Item.
Return type: presentation.PresentationContext

property transfer_syntax¶

Return the Transfer Syntax, if available.

Returns: If no Transfer Syntax Sub-item or an empty Transfer Syntax Sub-item has been sent by the Acceptor then returns None, otherwise returns the Transfer Syntax Sub-item’s transfer syntax UID.
Return type: pydicom.uid.UID or None