Method and device for processing and for searching for an object by signals corresponding to images
A method of representing an object appearing in a still or video image, by processing signals corresponding to the image, comprises deriving the peak values in CSS space for the object outline and applying a non-linear transformation to said peak values to arrive at a representation of the outline.
1. A method of representing an object appearing in an image or a sequence of images, using at least one processor to process signals corresponding to the image, the method comprising:
deriving using said at least one processor, a plurality of co-ordinate value pairs for peaks of the outline of the object in curvature scale space on the basis of the signals, one co-ordinate value of each co-ordinate pair being a peak height co-ordinate value; and
applying a scaling transformation to the peak height co-ordinate values, scaling each peak height co-ordinate value by a scaling factor not applied to the values of the other co-ordinate, to arrive at a representation of the outline.
2. A method as claimed in claim 1 wherein the scaling is independent of the number of co-ordinate value pairs.
3. A method of searching for an object in an image or sequence of image using at least one processor to process signals corresponding to images, the method comprising:
inputting a query in the form of a two-dimensional outline deriving a descriptor of said outline using a method as claimed in claim 1 ;
obtaining a descriptor of objects in a stored images derived using a processor to perform a method as claimed in claim 1 ;
comparing said query descriptor with each descriptor for a stored object; and
selecting and displaying at least one result corresponding to an image containing an object for which the comparison indicates a degree of similarity between the query and said object.
4. An apparatus comprising:
an image database storing an image or a sequence of images; and
a processor configured to perform the method of claim 1 or claim 3 .
5. A computer system comprising:
an image database storing an image or a sequence of images;
a display unit; and
a control unit programmed to perform the method of claim 1 or claim 3 .
6. A computer-readable storage medium storing computer-executable process steps for implementing a method as claimed in claim 1 or claim 3 .