Nested Quantization Index Modulation for Reversible Watermarking and Its Application to Healthcare Information Management Systems

<table>The PSNR of the watermarked image of chest (X-ray) at various quantization steps <svg height="12.1125" id="M93" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 14.8 12.1125" width="14.8" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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q-30 16 -75 16q-58 0 -92 -27q-49 -39 -78.5 -112t-29.5 -136q0 -34 8.5 -52.5t21.5 -18.5q40 0 109.5 63.5t103.5 115.5q16 53 32 151z" id="x1D45E"></path></g>
<g transform="matrix(.012,0,0,-.012,8.413,11.763)"><path d="M384 0h-275v27q67 5 81.5 18.5t14.5 68.5v385q0 38 -7.5 47.5t-40.5 10.5l-48 2v24q85 15 178 52v-521q0 -55 14.5 -68.5t82.5 -18.5v-27z" id="x31"></path></g>
</svg> and <svg height="12.1125" id="M94" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 14.8 12.1125" width="14.8" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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q-30 16 -75 16q-58 0 -92 -27q-49 -39 -78.5 -112t-29.5 -136q0 -34 8.5 -52.5t21.5 -18.5q40 0 109.5 63.5t103.5 115.5q16 53 32 151z" id="x1D45E"></path></g>
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Computational and Mathematical Methods in Medicine

fig13

Figure 13

Figure 13: Nested Quantization Index Modulation for Reversible Watermarking and Its Application to Healthcare Information Management Systems 