Matching of digital images to acquisition devices

A computer-readable storage medium storing a computer program executable by a computer for identifying a digital acquisition device that captures an image using red, green, and blue channels, the computer program containing:

• an obtaining code for obtaining at least a makernote tag data containing a first non-public whitepoint calibration data of a suspected digital acquisition device;
• a locating code for locating a makernote tag data in an image file to be matched;
• a searching code for searching for a second non-public whitepoint calibration data within the makernote tag data located in the image file to be matched;
• a comparing code for comparing the first non-public whitepoint calibration data with the second non-public whitepoint calibration data;
• and
• an identifying code for identifying the suspected digital acquisition device as a source of the test image file if the first and second non-public whitepoint calibration data match,
• wherein each of the first and second non-public whitepoint calibration data contains a calibration value of the green channel, a calibration value of the red channel, and a calibration value of the blue channel,
• wherein the searching code is further configured to:
• detect a pattern of the green channel calibration value, the red channel calibration value, and the blue channel calibration value contained in the image file to be matched;
• and
• first detect the calibration value of the most transmissive channel among the green, red, and blue channels, and then expand around a location of the detected most transmissive channel to detect the calibration values of other channels among the green, read, and blue channels.