There are two ways to specify transfer syntax (compression) for DICOM image saving: SaveFormat parameter, and TransferSyntax DICOM format option. SaveFormat (ImGearSavingFormats) is an easy-to-use shortcut, while TransferSyntax option provides the full selection of transfer syntaxes for image saving.

ImGearSavingFormats	ImGearCompressions	Transfer Syntax
DICOM	AUTO	Defined by SaveSyntax control parameter
DICOM_UNCOMP	NONE	ImplicitLittleEndian
DICOM_RLE	RLE	RLE
DICOM_JPEG	JPEG	JPEG Lossy
DICOM_JPEG2K	JPEG2K	JPEG2K Lossy