Abstract: Systems and methods are provided for detecting edges in an image. In an example method, the image is smoothed using a filter. A gradient magnitude and angle are determined for each pixel of the image. A non-maximum suppression is performed on the resulting image data. A double threshold with an upper and a lower threshold are applied to the resulting image data to determine the edges in the image. The upper and the lower thresholds are calculated automatically using a distribution of intensity values of the image. In example systems, an image is acquired by a camera, or other image acquisition units. An image processing unit is configured to detect the edges in the image using an adaptive threshold edge detection method.

Abstract: Systems and methods are provided for detecting edges in an image. In an example method, the image is smoothed using a filter. A gradient magnitude and angle are determined for each pixel of the image. A non-maximum suppression is performed on the resulting image data. A double threshold with an upper and a lower threshold are applied to the resulting image data to determine the edges in the image. The upper and the lower thresholds are calculated automatically using a distribution of intensity values of the image. In example systems, an image is acquired by a camera, or other image acquisition units. An image processing unit is configured to detect the edges in the image using an adaptive threshold edge detection method.

Abstract: A method and device are described which are configured to establish whether a traffic sign has at least one graphical feature extending linearly thereon. A portion of image data which represents at least a portion of the traffic sign is identified. Coefficients of a two-dimensional spectral representation of the portion of the image data are calculated. The coefficients of the two-dimensional spectral representation are determined for Fourier space coordinates disposed along a line in Fourier space. Based on the determined coefficients it is established whether the traffic sign has the at least one graphical feature extending linearly on the traffic sign.