A document authentication method determines the authenticity of a target hardcopy document, which purports to be a true copy of an original hardcopy document. The method compares a binarized image of the target document with a binarized image of the original document which has been stored in a storage device. The image of the original document is generated by binarizing a scanned grayscale image of the original document. Halftone and non-halftone text areas in the grayscale image area separated, and the two types of text are separately binarized. The non-halftone text areas are then down-sampled. During authenticating, a scanned grayscale image of the target document is binarized by separating halftone and non-halftone text areas and binarizing them separately, and then down-sampling the non-halftone text areas. The binarized images of the target document and the original document are compared to determine the authenticity of the target document.

A document authentication method determines the authenticity of a target hardcopy document, which purports to be a true copy of an original hardcopy document. The method compares a binarized image of the target document with a binarized image of the original document which has been stored in a storage device. The image of the original document is generated by binarizing a scanned grayscale image of the original document. Halftone and non-halftone text areas in the grayscale image area separated, and the two types of text are separately binarized. The non-halftone text areas are then down-sampled. During authenticating, a scanned grayscale image of the target document is binarized by separating halftone and non-halftone text areas and binarizing them separately, and then down-sampling the non-halftone text areas. The binarized images of the target document and the original document are compared to determine the authenticity of the target document.

An image reading apparatus includes a gray reference member, a reading unit, an adjusting unit, a calibration unit, a storage unit, and a control unit. The control unit is configured to execute a first preprocessing and a second preprocessing. The first preprocessing includes: acquiring first black data from one line worth of image data; acquiring white data; calculating white-black difference data; acquiring first light gray data; and calculating first light gray-black difference data. The second processing includes: acquiring second black data from the one line worth of the image data; acquiring second light gray data; calculating second light gray-black difference data; calculating a change ratio by dividing the second light gray-black difference data by the first light gray-black difference data; and calculating calibration data by multiplying the white-black difference data by the change ratio. Shading of the image data is calibrated in response to the calibration data.

An image reading apparatus includes a gray reference member, a reading unit, an adjusting unit, a calibration unit, a storage unit, and a control unit. The control unit is configured to execute a first preprocessing and a second preprocessing. The first preprocessing includes: acquiring first black data from one line worth of image data; acquiring white data; calculating white-black difference data; acquiring first light gray data; and calculating first light gray-black difference data. The second processing includes: acquiring second black data from the one line worth of the image data; acquiring second light gray data; calculating second light gray-black difference data; calculating a change ratio by dividing the second light gray-black difference data by the first light gray-black difference data; and calculating calibration data by multiplying the white-black difference data by the change ratio. Shading of the image data is calibrated in response to the calibration data.

Remote deposit of checks can be facilitated by a financial institution. A customer's general purpose computer and image capture device may be leveraged to capture an image of a check and deliver the image to financial institution electronics. Additional data for the transaction may be collected as necessary. The transaction can be automatically accomplished utilizing the images and data thus acquired.

Remote deposit of checks can be facilitated by a financial institution. A customer's general purpose computer and image capture device may be leveraged to capture an image of a check and deliver the image to financial institution electronics. Additional data for the transaction may be collected as necessary. The transaction can be automatically accomplished utilizing the images and data thus acquired.