Application of Quad Tree for low bitrate compression

Quad Tree algorithm is an efficient method for image compression at lower bit rates. It divides the image into four equal quadrants based on a threshold. The threshold is chosen from image characteristics using Otsu thresholding method. The image regions obtained from the Quad Tree decomposition are approximated by using a first order polynomial. Polynomial approximation coefficients now represent the pixel values. Its performance is better than JPEG at lower bitrates.