Table of Contents

NAME

QccWAVSubbandPyramidShapeAdaptiveDWT, QccWAVSubbandPyramidInverseShapeAdaptiveDWT - separable 2D shape-adaptive discrete wavelet transform and inverse transform for subband-pyramid data

SYNOPSIS

#include "libQccPack.h"

int QccWAVSubbandPyramidShapeAdaptiveDWT(QccWAVSubbandPyramid *subband_pyramid, QccWAVSubbandPyramid *mask, int num_levels, const QccWAVWavelet *wavelet);
int QccWAVSubbandPyramidInverseShapeAdaptiveDWT(QccWAVSubbandPyramid *subband_pyramid, QccWAVSubbandPyramid *mask, const QccWAVWavelet *wavelet);

DESCRIPTION

QccWAVSubbandPyramidShapeAdaptiveDWT() calls QccWAVWaveletShapeAdaptiveDWT2D(3) to perform a separable 2D shape-adaptive discrete wavelet transform (SA-DWT) on the matrix field of subband_pyramid. num_levels is the number of levels (scales) of decomposition to perform; the num_levels field of subband_pyramid is set to num_levels. mask is the transparency mask defining the shape of the data to be transformed; the matrix field of mask is passed as the transparency mask to QccWAVWaveletShapeAdaptiveDWT2D(3) . During the process of performing the 2D SA-DWT, the mask is transformed with a Lazy wavelet transform so as to correctly indicate where valid coefficients reside in the wavelet domain in the transformed subband_pyramid. The transformed mask is return in mask upon completion of QccWAVWaveletSubbandPyramidShapeAdaptiveDWT().

QccWAVSubbandPyramidInverseShapeAdaptiveDWT() calls QccWAVWaveletInverseShapeAdaptiveDWT2D(3) to perform a separable 2D inverse SA-DWT on the matrix field of subband_pyramid. The number of levels of the inverse transform is retrieved from the num_levels field of subband_pyramid; num_levels is set to 0 upon return of QccWAVSubbandPyramidInverseShapeAdaptiveDWT(). mask should be the Lazy-wavelet transformed mask that was output by QccWAVWaveletSubbandPyramidShapeAdaptiveDWT(). Upon return from QccWAVSubbandPyramidInverseShapeAdaptiveDWT(), mask is the original transparency mask; i.e., the mask that indicates where valid data resides in the original spatial domain.

RETURN VALUES

These routines return 0 on success and 1 on error.

SEE ALSO

QccWAVWaveletShapeAdaptiveDWT2D(3) , QccWAVWaveletInversShapeAdaptiveDWT2D(3) , QccWAVWavelet(3) , QccPackWAV(3) , QccPack(3)

S. Li and W. Li, "Shape-Adaptive Discrete Wavelet Transforms for Arbitrarily Shaped Visual Object Coding," IEEE Transactions on Circuits and Systems for Video Coding, vol. 10, pp. 725-743, August 2000.

ISO/IEC 14496-2, "Information Technology -- Coding of audio-visual objects -- Part 2: Visual," MPEG-4 Standard, Amendment 1, July 2000.

AUTHOR

Copyright (C) 1997-2021 James E. Fowler

Table of Contents



Get QccPack at SourceForge.net. Fast, secure and Free Open Source software downloads