acknowledgements for ansi/nist-itl 1-2011 - NIST Visual Image ...

ANSI/NIST-ITL 1-2011 - UPDATE 2013 DRAFT VERSION8.17.9 Field 17.009: Transmitted horizontal pixel scale / THPSThis field is mandatory if an image is present in Field 17.999. Otherwise it is absent.See Section 7.7.8.4 for details.8.17.10 Field 17.010: Transmitted vertical pixel scale / TVPSThis field is mandatory if an image is present in Field 17.999. Otherwise it is absent.See Section 7.7.8.5 for details.8.17.11 Field 17.011: Compression algorithm / CGAThis field is mandatory if an image is present in Field 17.999. Otherwise it is absent.Itshall specify the algorithm used to compress the transmitted color or grayscale images.See Section 7.7.9.2 for a detailed description of this field. The baseline JPEG algorithm(ISO/IEC 10918) shall not be used for Type-17 iris images. It has been shown that bothfalse non-match and false match rates increase due to the presence of tiling artifactsintroduced by JPEG's discrete cosine transform. While JPEG was allowed in priorversions of this standard, it shall not be allowed for new images. Implementers may wantto support JPEG decoding for handling legacy images. If legacy images were stored inJPEG, they should be converted to PNG prior to transmission, with this transformationnoted in Field 17.902: Annotation information / ANN.8.17.12 Field 17.012: Bits per pixel / BPXThis field is mandatory if an image is present in Field 17.999. Otherwise it is absent.See Section 7.7.8.6 for details.8.17.13 Field 17.013: Color space / CSPThis field is mandatory if an image is present in Field 17.999. Otherwise it is absent. SeeSection 7.7.10 for details. If Field 17.025: Effective acquisition spectrum / EAS is setto “NIR” this field shall be set to “GRAY”.8.17.14 Field 17.014: Rotation angle of eye / RAEThis optional field shall indicate the in-plane rotation angle of the iris. Such rotation canbe caused by head tilt, camera tilt, and also by the common natural rotation of the eyeitself. The rotation angle of the eye encoded in this field is defined here in terms of roll ofthe subject's head. The angle is defined, and measured in degrees, as the angle between aline joining the pupil or iris centers of the left and right eyes, and the horizontal axis ofthe imaging system. As shown in Figure 18, an angle is positive for counter-clockwiserotation, as seen from the camera, of this line relative to the camera’s horizontal axis.The in-plane eye rotation angle shall be recorded as angle = round (65535 * angle / 360)modulo 65535 170 . The value “FFFF” indicates that rotation angle of eye is undefined. This170In the 2007 and 2008 versions of the standard, there was a typographical error of 65536.352