A Secret Image Sharing Method Using Integer-to-Integer Wavelet Transform

We present a new image sharing method based on the integer-to-integer (ITI) wavelet transform and Shamir´s (r, m) threshold scheme that provide highly compact shadows for real time progressive transmission. Our approach, working in the wavelet domain, processes the transform coefficients in each subband, divides each of the resulting combination coefficient into m shadows for sharing, and recovers the complete secret image using any r or more shadows (rlesm). We take advantage of the properties of the wavelet multi-resolution representation of an image, such as coefficient magnitude decay and excellent energy compaction, to design combination procedures for transform coefficients and processing sequences in wavelet decomposition subbands such that compact shadows for real time progressive transmission are obtained