Color Image Transcoding of Lossless Encoder and Standard Lossy Decoder based on JP2K

Abstract

In JPEG2000 (JP2K) color image system, loss less coding signal is not able to be reconstructed with lossy decoder directly. Then, this report proposes a new transcoding between lossless encoder and standard lossy decoder for color image signals base on JP2K. A proposed encoder is required reversible color transform (RCT) and reversible discrete wavelet transform (RDWT) with compatibility to standard lossy decoder based on JP2K (JP2K lossy decoder). To improve the compatibility, proposed encoder is designed by using Non-scaled RCT and Non-Scaled RDWT with embedding scaling parameter into quantization header. Then, this method can be practical use with JP2K lossy decoder without any change. It also reduces total rounding error and lifting steps. The results show that proposed method can keep lossless coding performance and improve transcoding functionality to JP2K lossy decoder. The quality of transcoding image was achieved to 50.05 dB (PSNR).