Here we are implementing a method to zoom given image in wavelet domain. To zoom an image, concepts of multiresolution analysis along with zerotree philosophy is used. The wavelet transform has been identified as an effective tool for time-frequency representation of signals. It can decompose a digital image into some frequency sub-images, each represented with proportional frequency resolution. Finer level coefficients are estimated using wavelet transform. In this method smoothing effect is reduced as high frequency components are added. The zoomed images are more sharper and less blocky. The performance can be measured by calculating peak signal to noise ratio(PSNR)& Mean Square Error(MSE) . It is observed that this method gives much better PSNR & MSE compared to other methods.

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Wavelet Multiresolution Zooming Zerotree