Image header information
An image header is associated with every image captured by the scanner. Following is a list of information available in the image header.
Image length size of the image.
Image identifier indicates whether the image is front black and white, rear black and white, front color or rear color.
Resolution the scanner records the selected scanner image resolution in dots per inch.
Y axis upper left pixel vertical offset to upper left corner of the image. For more information, see the next section entitled “Zone processing”.
Width the scanner records the number of
Length the scanner records the
Compression type the scanner records the compression type used. Values for black and white images are: No Compression, Group III, Group III 2D or Group IV. The values for grayscale or color images are No Compression or JPEG.
Polarity the scanner records image polarity. White pixels can be indicated as 0 or 1.
Multifeed — indicates whether or not a multifeed was detected when the image was scanned. This information can be used by the host to assist operators during error recovery.
Deskew enabled — a flag in the image header reflects whether the scanner was asked to perform deskew. If deskew is enabled, the image header also indicates whether or not the document was deskewed.
Deskewed a flag the image header indicates whether or not the image was deskewed.
Skew angle image header records the skew angle which was determined for the scanned image. A severe skew angle may result in no deskew being performed. If the scanner is unable to determine a skew angle, the image will not be deskewed. The skew angle field of the image header will be set to 0.
Print string the actual character string printed on the document is returned in the image header. This string may be up to 40 characters in length. Print strings are defined in the host application.
Sequential counter the scanner assigns a unique Sequential ID Number to each document which is returned in the image header. The host application controls the setting of the starting value for this counter.
