Quaternion Wavelet Analysis and Application in Image Denoising

<table class="table-group" width="800px"><tr class="fig-image" id="a"><td><img alt="493976.fig.007a" src="https://static.hindawi.com/articles/mpe/volume-2012/493976/figures/493976.fig.007a.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(a) </b>Noisy image </td></tr></table></td></tr><tr class="fig-image" id="b"><td><img alt="493976.fig.007b" src="https://static.hindawi.com/articles/mpe/volume-2012/493976/figures/493976.fig.007b.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(b) </b>Hard</td></tr></table></td></tr><tr class="fig-image" id="c"><td><img alt="493976.fig.007c" src="https://static.hindawi.com/articles/mpe/volume-2012/493976/figures/493976.fig.007c.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(c) </b>LAWML </td></tr></table></td></tr><tr class="fig-image" id="d"><td><img alt="493976.fig.007d" src="https://static.hindawi.com/articles/mpe/volume-2012/493976/figures/493976.fig.007d.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(d) </b>SURE-LET </td></tr></table></td></tr><tr class="fig-image" id="e"><td><img alt="493976.fig.007e" src="https://static.hindawi.com/articles/mpe/volume-2012/493976/figures/493976.fig.007e.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(e) </b>P-Bivariate </td></tr></table></td></tr><tr class="fig-image" id="f"><td><img alt="493976.fig.007f" src="https://static.hindawi.com/articles/mpe/volume-2012/493976/figures/493976.fig.007f.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(f) </b>Our method </td></tr></table></td></tr></table>

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Mathematical Problems in Engineering

Quaternion Wavelet Analysis and Application in Image Denoising

Figure 7