Transfer Patch Code
The image header reflects when a Transfer patch code is detected on a document. A document containing a Transfer patch is considered to be a Level 0 document. The IA level for the next document following the Transfer patch is assigned to the level (Level 2 or Level 3) that has been previously set. The scanner cannot print on documents containing Transfer patches. In the image header for the document containing the Transfer patch, the document level is returned as 0 and the patch type returned as T to reflect the Transfer patch definition. For the document following the Transfer patch document the image header will contain a document level of 2 or 3 depending on the Transfer patch type definition and will reflect no patch detected.
Toggle Patch
The Toggle patch is a Type 4 patch that is used to trigger the scanner to switch from the current image stream (black and white) to the alternative image stream (color/grayscale). This logic is performed inside the scanner. Images of the toggle patch sheet will not be returned to the host unless you also enable patch reading and select the Type 4 patch. Common uses for this patch would be a document set, which is primarily black and white but has some color content. Placing a Toggle Patch sheet before and after the color document(s) would allow changing from black and white to color and back
NOTE: Toggle patch may also be used to trigger the scanner to switch from black and white to grayscale and vice versa.
Additional Patch Codes
Additional patch codes enable the host to implement any type of
When an additional patch is detected, this document is considered a Level 0 document and will not cause the IA to change. The image header indicates that this is an additional patch document by returning a patch type, which matches the patch detected. The scanner will not print on documents containing these additional patches.