Region of interest image coding using IWT and partial bitplane block shift for network applications

In this paper, a flexible region of interest (ROI) image coding method so-called partial block bitplane shift (PBBShift) is presented for JPEG2000. The new method offers two strategies - bitplane block scaling (BBS) and partial bitplane shift (PBS), which support arbitrarily shaped single or multiple ROI. In BBS, all bitplanes of ROI and background (BG) are divide into four parts - most significant ROI (MSR), general significant ROI (GSR), general significant BG (GSB), and least significant BG (LSB). In PBS, all bitplanes of MSR are shifted up over all residual bitplanes. The bitplanes in LSB are shifted down below all bitplanes. The bitplanes of GSR and GSB are not shifted. Experimental result shows that the presented method can flexibly adjust the compression quality between ROI and background by selecting an arbitrary scaling value without any ROI shape information. Additionally, PBBShift can efficiently code multiple ROIs with different degrees of interest in an image.