The OdDbRasterImage and OdDbRasterImageDef classes are used to insert a picture
from an external raster file. OdDbRasterImage entities reside in model or paper
space of a drawing. They specify the position and orientation of the image,
brightness, clipping boundary, and other properties. Each OdDbRasterImage entity
references a single OdDbRasterImageDef (definition) object such as a block reference
entities and reference block definitions. OdDbRasterImagedef objects reside
in a special dictionary named ACAD_IMAGE_DICT. Each OdDbRasterImage entity must
have a reference to an OdDbRasterImageDef object.
OdDbRasterImagedef objects store the source raster file name, size in pixels,
and other properties. The same raster definition object can be referenced by
multiple raster entities.