Image Processing Reference
In-Depth Information
VIFP = 0.6359, WSNR = 34.24 and C w PSNR = 40.88, while for MaxShift coded image
VIFP = 0.3561, WSNR = 31.34, and C w PSNR = 37.18. Thus, these metrics predicts that there is
an important perceptual diference between ROI methods, being ρGBbBShift method beter
than MaxShift method.
FIGURE 10 Example of a medical application. 1024 x 1024 pixel Image mdb202 from PEIPA
image database. ROI is a patch with coordinates [120 440 376 696], whose size is 1/16 of the
image. Decoded images at 0.12 bpp using MaxShift method ((a-b) φ = 8) in JPEG2000 coder
and ρGBbBShift method ((c-d) BPmask = 1111000110110000) in H i -SET coder. (a) MaxShift
method in JPEG2000 coder, 0.12 bpp. (b) Patch of (a) portrayed both ROI and BG areas.(c)
ρGBbBShift method in H i -SET coder, 0.12 bpp. (d) Patch of (c) portrayed both ROI and BG
5 Conclusions
A perceptual implementation of the ROI, ρGBbBShift, is proposed, which is a generalized
method that can be applied to any wavelet-based compressor. We introduced ρGBbBShift
method to the H i -SET coder and it visually improves the results obtained by previous methods
like MaxShift and GBbBShift. Our experiments show that ρGBbBShift into H i -SET provides an
important perceptual difference regarding the MaxShift method into JPEG2000, when it is ap-
plied to conventional images like Lenna or Barbara .
Search WWH ::

Custom Search