int QccWAVSubbandPyramidZeroSubband(QccWAVSubbandPyramid
*subband_pyramid, int subband);
int QccWAVSubbandPyramidSubtractMean(QccWAVSubbandPyramid
*subband_pyramid, double *mean, const QccSQScalarQuantizer *quantizer);
int QccWAVSubbandPyramidAddMean(QccWAVSubbandPyramid *subband_pyramid,
double mean);
QccWAVSubbandPyramidZeroSubband() sets the coefficients of the specified subband in subband_pyramid to zero. subband is the subband number of the desired subband (see QccWAVSubbandPyramid(3) for more detail on addressing individual subbands in the subband-pyramid structure).
QccWAVSubbandPyramidSubtractMean() calculates the mean value of the coefficients of the baseband of subband_pyramid, optionally quantizes it with a scalar quantizer, and subtracts the result from the baseband coefficients. If quantizer is non-NULL, QccSQScalarQuantization(3) and QccSQScalarInverseQuantization(3) are called in succession to quantize the calculated mean, and this quantized mean is subtracted from the baseband coefficients in subband_pyramid. If quantizer is NULL, no quantization is performed so that the calculated mean is subtracted directly. If mean is non-NULL, the value subtracted from the coefficients (either the mean or the quantized mean) is returned as mean.
QccWAVSubbandPyramidAddMean() adds value mean to all baseband coefficients of subband_pyramid. It is intended to implement the reverse operation of QccWAVSubbandPyramidSubtractMean(), so mean would be returned from this latter routine in most cases.
M. Antonini, M. Barlaud, P. Mathieu, and I. Daubechies, "Image Coding Using Wavelet Transform," IEEE Transactions on Image Processing, vol. 1, pp. 205-220, April 1992.