Vehicular target acquisition and tracking using a generalized hough transform for missile guidance

A method, comprising:

• acquiring an image of a scene containing a vehicle with a high resolution off-missile imager;
• performing edge detection on the image to produce a silhouette image;
• performing a Hough transform on the silhouette image to detect a best fit of a parameterized object to the vehicle;
• and
• passing position, size and orientation parameters of the object from the high resolution imager to a missile seeker on a missile over a low bandwidth channel, said missile seeker including a low resolution imager that acquires low resolution images of the scene with a different line-of-sight than the high resolution imager and a missile tracker that recomputes the Hough transform on the low resolution images in a constrained spaced based on the parameters to compensate for the different line-of-sight.

A method, comprising:

• acquiring an image of a scene containing a vehicle;
• performing edge detection on the image to produce a silhouette image;
• performing a Hough transform on the silhouette image to detect a best fit of the vehicle to a parameterized rounded rectangle given by:
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• wherein the vehicle lies along the x and y axes with parameters including center coordinates xc, yc, major and minor axes a,b, an orientation Θ and exponent n;
• and
• passing parameters xc, yc, a, b, θ to a missile tracker.

An apparatus, comprising:

• a missile;
• an imager for acquiring an image of a scene containing a vehicle;
• an automatic target recognizer (ATR) for placing an initial non-conforming track gate over the vehicle in the image;
• and
• a missile tracker including a target acquisition module for acquiring a vehicle said target acquisition module performing edge detection on a portion of the image within the track gate to produce a silhouette image and performing a Hough transform on the silhouette image to fit a parameterized object to the vehicle and using the position, size and orientation parameters of the object to adjust the track gate so that it is approximately conformal with the vehicle, said missile tracker using the conformal track gate to track the acquired vehicle to impact.

An apparatus, comprising:

• A missile;
• a high resolution off-missile imager that acquires high resolution images of the scene;
• an off-missile target acquisition module that computes the Hough transform on the high resolution image and outputs the parameters;
• a low bandwidth channel that communicates the parameters to the missile;
• and
• a missile seeker including
• a low resolution on-missile imager that acquires low resolution images of the scene with a different line-of-sight than the high resolution imager;
• and
• a missile tracker having an on-missile target acquisition module that receives the parameters and recomputes the Hough transform on the low resolution images in a constrained space based on the parameters to compensate for the different line-of-sight and passes the parameters to the missile tracker.

A method of tracking a target vehicle from a missile, comprising:

• acquiring an image of a scene containing a vehicle;
• placing an initial track gate around the vehicle;
• using a missile tracker's target acquisition module to (a) perform edge detection on the portion of the image within the track gate to produce a silhouette image, (b) perform a Hough transform on the silhouette image to fit a parameterized object to the vehicle to extract position, size and orientation parameters of the object and (c) adjust the track gate based on said position, size and orientation parameters so that said track gate is approximately conformal with the vehicle;
• and
• passing the conformal track gate to the missile tracker to track the acquired vehicle to impact.