Four Walsh Transform Sectors Feature Vectors for Image Retrieval From Image Databases
The work of this paper presents the new idea of using Walsh transform to generate the feature vector for content based image retrieval. The complex Walsh transform is conceived by multiplying Sal functions by j and combining them with Cal functions of the same sequency. The angle is calculated by taking tan inverse of sal/cal in the range of 0 to 360 degrees which is divided into 4 sectors. The mean of real and imaginary values of these sectors in all three color planes are considered to design the feature vector of 24 components all together. The algorithm proposed here is worked over database of 270 images spread over 11 different classes. The Euclidean distance is used as similarity measure.