The Image object stores the original page image either scanned, loaded from image file or memory, together with the engine-managed additional, generated images. The generated images are the following:
Primary image: the result of the image preprocessing and image manipulation, that occurs on the original image.
OCR image: a black-and-white image created by the first operation that requires it, for example preprocessing, page-parsing, or recognition. The OCR image is only available after the recognition.
Thumbnail image: a smaller version of the current image.
The role of this object is to facilitate access to the managed images, and to provide a basic operation set for image manipulation. A large image manipulation library is available through the ImageFile object.
Redaction is a special case for image handling. This operation writes back to primary, OCR and original images stored in the program. Only the original image, stored in file outside the program, remains untouched. In the case of scanning, no unredacted image is available. Therefore we suggest that you apply redaction to a copy.