Preprocessing for Discrete Multiwavelet Transform of Two-Dimensional Signals
نویسندگان
چکیده
Multiwavelet transform can be implemented by treestructured matrix lter bank, which operates on vector sequence input instead of scalar ones. Therefore, unlike in scalar wavelet system, preprocessing is usually required to extract vector sequence input from the input signal for better performance. A 2-D approximation-based preprocessing scheme for GHM (Geronimo, Hardin and Massopust) discrete multiwavelet transform of 2-D signals is proposed. Compared with the recent 1-D approximation-based method, the proposed scheme reduces the preprocessing computational complexity by 65% while maintaining similar energy compression ability.
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