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

<table>Extraction of the watermark, <svg height="11.375" id="M37" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 17.4 11.375" width="17.4" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,0,0,-.017,.062,11.113)"><path d="M1004 650l-6 -29q-54 -6 -71 -19.5t-51 -74.5l-271 -539h-33l-98 506h-3l-258 -506h-30l-78 532q-10 67 -21.5 80t-66.5 21l6 29h241l-8 -29l-26 -5q-34 -6 -41 -16t-3 -47l59 -425h4l251 510h31l102 -510h2q150 299 198 423q14 40 8.5 48.5t-47.5 16.5l-28 5l7 29h231z
" id="x1D44A"></path></g>
</svg>, from the watermarked image, <svg height="14.3125" id="M38" style="vertical-align:-2.2932pt" version="1.1" viewbox="0 0 25.7875 14.3125" width="25.7875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,0,0,-.017,.062,11.4)"><path d="M745 361q0 -134 -83.5 -233t-214.5 -130l16 -11q97 -67 250 -132l-8 -23q-76 3 -131 16q-81 19 -242 125l-20 13q-129 8 -209 91t-80 208q0 160 116 271t289 111q136 0 226.5 -83t90.5 -223zM645 356q0 127 -57.5 201.5t-169.5 74.5q-126 0 -210.5 -104.5t-84.5 -248.5
q0 -97 46 -166.5t129 -87.5l84 15l29 -19q104 21 169 121.5t65 213.5z" id="x1D444"></path></g><g transform="matrix(.017,0,0,-.017,13.118,11.4)"><path d="M730 650l-8 -28q-52 -4 -72 -18t-64 -77q-79 -113 -321 -539h-33l-119 541q-13 59 -29.5 73t-66.5 20l7 28h245l-8 -28l-28 -5q-33 -6 -40.5 -15.5t-0.5 -38.5l102 -450h2q191 320 246 430q21 42 15.5 56t-43.5 19l-31 4l7 28h240z" id="x1D449"></path></g>
</svg>, based on the conventional QIM scheme.</table>

Computational and Mathematical Methods in Medicine

fig5

Figure 5

Figure 5: Nested Quantization Index Modulation for Reversible Watermarking and Its Application to Healthcare Information Management Systems 