An object detection and classification system for a hazard detection and information system comprising: an image sensor configured to capture an image from an environment surrounding the system, the image from the environment surrounding the system including one or more keypoints, wherein keypoints are points in an image that define locations that are likely of interest; extracting circuitry communicatively coupled to the image sensor and configured to extract at least one feature value from at least one of the one or more keypoints in the image from the environment surrounding the system; query point evaluation circuitry communicatively coupled to the image sensor and the extracting circuitry and configured to classify an object by sampling a periodic descriptor function for a query point in the image from the environment surrounding the system to produce a sample value, the periodic descriptor function depending on the distance between at least one of the one or more keypoints and the query point in complex space, the periodic descriptor function further depending on at least one feature value extracted from at least one of the one or more keypoints in the image from the environment surrounding the system; and a signal bus configured to transmit a signal to the operator of the system if the sample value satisfies an alert condition, • wherein the periodic descriptor function is defined as follows: F ζ = 1 N ∑ k = 0 N − 1 z k − z c e i 2 πf z k ζ where N is the number of keypoints in the image from the environment surrounding the system in the neighborhood of the query point, z c is the query point represented in complex space, z k is the k th keypoint, f (z k) is the feature value of the k th keypoint, and ζ is the continuous independent variable of the descriptor function F(ζ), or • wherein the periodic descriptor function is a scale-invariant or rotation-invariant function defined as follows: F ζ = 1 z m ∑ k = 0 N − 1 z k − z c e i 2 πf z k ζ wherein: z m = 1 N ∑ k = 0 N − 1 z k − z c an image sensor configured to capture an image from an environment surrounding the system, the image from the environment surrounding the system including one or more keypoints, wherein keypoints are points in an image that define locations that are likely of interest; extracting circuitry communicatively coupled to the image sensor and configured to extract at least one feature value from at least one of the one or more keypoints in the image from the environment surrounding the system; query point evaluation circuitry communicatively coupled to the image sensor and the extracting circuitry and configured to classify an object by sampling a periodic descriptor function for a query point in the image from the environment surrounding the system to produce a sample value, the periodic descriptor function depending on the distance between at least one of the one or more keypoints and the query point in complex space, the periodic descriptor function further depending on at least one feature value extracted from at least one of the one or more keypoints in the image from the environment surrounding the system; and a signal bus configured to transmit a signal to the operator of the system if the sample value satisfies an alert condition, • wherein the periodic descriptor function is defined as follows: F ζ = 1 N ∑ k = 0 N − 1 z k − z c e i 2 πf z k ζ where N is the number of keypoints in the image from the environment surrounding the system in the neighborhood of the query point, z c is the query point represented in complex space, z k is the k th keypoint, f (z k) is the feature value of the k th keypoint, and ζ is the continuous independent variable of the descriptor function F(ζ), or • wherein the periodic descriptor function is a scale-invariant or rotation-invariant function defined as follows: F ζ = 1 z m ∑ k = 0 N − 1 z k − z c e i 2 πf z k ζ wherein: z m = 1 N ∑ k = 0 N − 1 z k − z c • wherein the periodic descriptor function is defined as follows: F ζ = 1 N ∑ k = 0 N − 1 z k − z c e i 2 πf z k ζ where N is the number of keypoints in the image from the environment surrounding the system in the neighborhood of the query point, z c is the query point represented in complex space, z k is the k th keypoint, f (z k) is the feature value of the k th keypoint, and ζ is the continuous independent variable of the descriptor function F(ζ), or • wherein the periodic descriptor function is a scale-invariant or rotation-invariant function defined as follows: F ζ = 1 z m ∑ k = 0 N − 1 z k − z c e i 2 πf z k ζ wherein: z m = 1 N ∑ k = 0 N − 1 z k − z c