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Optimizing Exchange, Receiving Compressed Images

When a connection is established between the application and the PACS server, a negotiation process occurs where the client and server agree on supported capabilities
The application sends a Presentation Context containing the SOP Class UID (identifier of the data type, e.g., CT Image Storage) and a list of Transfer Syntaxes (data encoding methods)

Each unique SOP Class UID can be encoded in different ways:

with compression
without compression
with different byte orders

The list of Transfer Syntaxes is set considering priority: the first Transfer Syntax supported by the PACS will be selected for use
The list must include a basic one, which is mandatory for support, Implicit VR Little Endian (1.2.840.10008.1.2)

Configuring the List:

In the application's main configuration file, located at:

For Windows C:\Users\Public\POVIDAR\VdViewer3\vdviewer.xml
For Linux \var\lib\POVIDAR\Vdviewer3\vdviewer.xml

find the element "SOPTransferSyntaxes", responsible for the set of rules mapping SOP Class UID to the list of Transfer Syntaxes
The structure looks as follows:


<SOPTransferSyntaxes description="">
    <!--=====================-->
    <SOPClass name="ComputedRadiographyImageStorage" uid="1.2.840.10008.5.1.4.1.1.1">
        <TransferSyntax uid="1.2.840.10008.1.2.4.50"/>
        <TransferSyntax uid="1.2.840.10008.1.2.4.51"/>
        <TransferSyntax uid="1.2.840.10008.1.2.4.70"/>
        <TransferSyntax uid="1.2.840.10008.1.2.1"/>
        <TransferSyntax uid="1.2.840.10008.1.2"/>
    </SOPClass>
    <SOPClass name="DigitalXRayImageStorageForPresentation" uid="1.2.840.10008.5.1.4.1.1.1.1">
        <TransferSyntax uid="1.2.840.10008.1.2.4.50"/>
        <TransferSyntax uid="1.2.840.10008.1.2.4.51"/>
        <TransferSyntax uid="1.2.840.10008.1.2.4.70"/>
        <TransferSyntax uid="1.2.840.10008.1.2.1"/>
        <TransferSyntax uid="1.2.840.10008.1.2"/>
    </SOPClass>

Each SOPClass element has a name attribute, providing a human-readable description of the data type in question, and a uid attribute, specifying the identifier of the data type
Between the opening and closing tags are TransferSyntax elements with a single uid attribute, which specifies the identifier of the desired Transfer Syntax

If problems arise with receiving data of a specific SOP Class UID type, the order of TransferSyntax elements should be changed (from higher to lower priority) or existing ones should be added/modified