A 2-D orientation-adaptive prediction filter in lifting structures for image coding.

Omer N Gerek; A Enis Cetin

doi:10.1109/tip.2005.859369

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A 2-D orientation-adaptive prediction filter in lifting structures for image coding.

Omer N Gerek·A Enis Cetin

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Abstract

Lifting-style implementations of wavelets are widely used in image coders. A two-dimensional (2-D) edge adaptive lifting structure, which is similar to Daubechies 5/3 wavelet, is presented. The 2-D prediction filter predicts the value of the next polyphase component according to an edge orientation estimator of the image. Consequently, the prediction domain is allowed to rotate +/-45 degrees in regions with diagonal gradient. The gradient estimator is computationally inexpensive with additional costs of only six subtractions per lifting instruction, and no multiplications are required.

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Algorithms Computer Graphics Data Compression Image Enhancement Image Interpretation, Computer-Assisted Numerical Analysis, Computer-Assisted Signal Processing, Computer-Assisted Journal Article Research Support, Non-U.S. Gov't

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Omer N Gerek, A Enis Cetin. 2006. A 2-D orientation-adaptive prediction filter in lifting structures for image coding.. https://doi.org/10.1109/tip.2005.859369

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