The change detection module 124 uses the image derivatives provided by the image processing module 123 to detect changes in the crop condition within an agricultural field. If certain criteria are met, the change detection module will generate a notification to be transmitted to the client system 110 via a network 140.

Image Filtering

Filtering of images provided by the observation system 110 or retrieved from the image store 121 is performed using the image filtering module 122. Image filtering is performed to ensure images are suitable for use in automated crop health change detection.

There are numerous reasons why an image may be unsuitable for change detection. Pixel values in an observed image obtained from a remote sensing platform are a measurement of electromagnetic radiation (EMR) originating from the sun (a quantity hereafter referred to as radiance), passing through the atmosphere, being reflected from objects on the Earth's surface (i.e., an agricultural field), then passing through part or all of the atmosphere once again before being received by a remote sensor (a quantity hereafter referred to as radiance). The proportion of radiance received by ground objects relative to the irradiance received by these objects (a measure hereafter referred to as surface reflectance) is of primary interest to remote-sensing applications, as this quantity may provide information on the characteristics of these objects. However, atmospheric effects can introduce detrimental impacts on the measured EMR signal in an observed image, which can render some or all of the image pixels inconsistent, inaccurate, and, generally untenable for use in accurate detection of crop health condition changes.