Abstract: A method of producing a gait representation for a subject, comprising the steps of: acquiring a sequence of images of the subject representing the gait of said subject; analysing each image of said sequence to identify one or more regions having a certain thickness based on a thickness characteristic function and a threshold value; for each image, removing said one or more regions from said image to produce a modified image; and combining said modified images in the sequence to produce a gait energy image. Calculating and applying a thickness characteristic to the images allows a better identification of regions of the images which are most affected by covariate factors such as carrying an object or wearing heavy clothing. Such covariate factors have been found most often to be associated with the more static parts of the subject, i.e. the torso. The more dynamic parts of the subject, i.e.

Abstract: There is described a method of encrypting a set of 2D input data, preferably image data. The method comprises obtaining the hash value of a password and re-sizing the hash value to fit the size of the 2D input data. The re-sized data is transformed using an irreversible transform, and the output of the transform is then used to encode the 2D data.

Abstract: There is described a method for detecting the presence of skin tone in an image. A gray scale representation of a pixel within the image is provided. Next, a red chrominance independent representation for is provided for the pixel. Then, the two representations are analysed to determine whether a difference in value between the representations corresponds with a the presence of a skin tone value. The present invention provides a rapid skin tone detection classifier particularly useful for real time applications.

Abstract: There is described a method of encrypting a set of 2D input data, preferably image data. The method comprises obtaining the hash value of a password and re-sizing the hash value to fir the size of the 2D input data. The re-sized data is transformed using an irreversible transform, and the output of the transform is then used to encode the 2D data.

Abstract: There is described a method for detecting the presence of skin tone in an image. A gray scale representation of a pixel within the image is provided. Next, a red chrominance independent representation for is provided for the pixel. Then, the two representations are analysed to determine whether a difference in value between the representations corresponds with a the presence of a skin tone value. The present invention provides a rapid skin tone detection classifier particularly useful for real time applications.