ImageGear .NET v25.1 - Updated
DICOM Metadata Structure
User Guide > File Formats and Compressions > File Formats > Metadata Structures > DICOM Metadata Structure

DICOM files contain one header and zero, one, or several image pages. Image header applies to all pages in the image. ImageGear.Net loads the same metadata tree for each page in the image, and attaches this tree to the corresponding page. ImageGear .NET does not put any tags to document level metadata for DICOM images.

This section provides information about the following:

DICOM Metadata Root Level

Name Id Type Value Type Value Value Length Read Only
Preamble Preamble Leaf Byte[]   128 No
MetaInfoHeader MetaInfoHeader Tree        
DataSet DataSet Tree        

MetaInfoHeader Level

Name Id Type Value Type Value Value Length Read Only
<tag name> <tag id> Leaf        

DataSet may contain subtrees, corresponding to DICOM tags that have "Sequence" (SQ) type. Sequences can non contain normal tags (leafs). Instead, each Sequence contains one or more "Items". Items can contain normal tags including Sequences. All items within one Sequence must have the same set of tags, but tag values can be different.

DataSet Level

Name Id Type Value Type Value Value Length Read Only
<tag name> <tag id> Leaf        
...            
<SQ tag name> <SQ tag id> Tree        
...            

Sequence Level

Name Id Type Value Type Value Value Length Read Only
Item Item Tree        
...            

Item Level

Name Id Type Value Type Value Value Length Read Only
<tag name> <tag id> Leaf        
...            
<SQ tag name> <SQ tag id> Tree        
...            

When ImageGear saves images, it overwrites the following tags:

Id Location Type
FileMetaInformationVersion MetaInfoHeader Leaf
TransferSyntaxUID MetaInfoHeader Leaf
SamplesPerPixel DataSet Leaf
PhotometricInterpretation DataSet Leaf
Rows DataSet Leaf
Columns DataSet Leaf
BitsAllocated DataSet Leaf
BitsStored DataSet Leaf
HighBit DataSet Leaf
PixelRepresentation DataSet Leaf
PlanarConfiguration DataSet Leaf
Red Palette Color Look Up Table Descriptor DataSet Leaf
Green Palette Color Look Up Table Descriptor DataSet Leaf
Blue Palette Color Look Up Table Descriptor DataSet Leaf
Red Palette Color Look Up Table Data DataSet Leaf
Green Palette Color Look Up Table Data DataSet Leaf
Blue Palette Color Look Up Table Data DataSet Leaf
PixelData DataSet Leaf