Patent ID: 9183457
Filing Date: 2015-11-10
Classification: G06K,G06T

Abstract:
1. A method for shadow detection in an image comprising multiple colour channels, wherein said image is compared with a background image and wherein said image and said background image: have an exposure of a common background, are divided into a plurality of image and background image evaluation areas respectively, each image evaluation area having a corresponding background image evaluation area covering the same area of said common background, and comprises the same multiple colour channels, wherein each possible combination of two colour channels in said image is identified, each combination of two colour channels defines a two dimensional coordinate system, and a shadow region is defined in each of said coordinate systems, wherein for each image evaluation area to be evaluated the method comprises the steps of: for each combination of two colour channels: classifying the image evaluation area as shadow if the difference value falls within the shadow region for all combinations of two colour channels; and classifying the image evaluation area as non-shadow if the difference falls outside the shadow region for any of the combinations of two colour channels.