A novel block truncation coding of color images by using quaternion-moment-preserving principle

To compress color-pixel blocks, a novel color BTC algorithm, called the quaternion-moment block truncation coding (QMBTC), is presented in this paper. The QMBTC are derived by using the quaternion arithmetic and moment-preserving principle. The proposed color BTC algorithm can adaptively truncate a pixel block into one or two output classes according to the distribution of color values inside the blocks. The experimental results show that the compression ratio will increase as compared with existing color BTC algorithms and the picture quality of reconstructed images is satisfactory.