Patent ID: 8903137

Claim:
A computer assisted method of assigning geographic coordinate data to a point depicted in digital geographic imagery, comprising: accessing, by one or more computing devices, a digital geographic image comprising a plurality of pixels; detecting, by one or more computing devices, a feature across a plurality of pixels in the digital geographic image, wherein the feature comprises a straight edge; generating, by the one or more computing devices, a mathematical model based at least in part on the feature, the mathematical model defining image coordinates along the feature in the digital geographic imagery with sub-pixel accuracy; identifying, by the one or more computing devices, a measurement point located on the feature; identifying, by the one or more computing devices, image coordinates associated with the measurement point with sub-pixel accuracy from the mathematical model; and associating, by the one or more computing devices, geographic coordinate data with the identified image coordinates wherein generating, by the one or more computing devices, a mathematical model comprises: defining, by the one or more computing devices, the straight edge as a mathematically defined line having a slope coefficient and an intercept coefficient in the image coordinate system; and estimating, by the one or more computing devices, one or more of the slope coefficient and the intercept coefficient of the mathematically defined line.