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float * get_lifting_factors( int & num_steps, float & dc_scale, float & nyq_scale)
[Declared in "../coresys/common/kdu_kernels.h"]
Returns a complete lifting factorization of the kernels. Since the kernels are symmetric, with odd least dissimilar lengths (lengths differ by 2), the lifting steps each involve symmetric 2-tap filters, characterized by a single factor.
Array of lifting factors, one for each successive lifting step in the forward (analysis) transform. For the inverse transform, the steps are applied in reverse order and the factors negated.
Used to return the number of lifting steps.
Used to return a scale factors by which the low-pass subband samples must be multiplied after all lifting steps are complete. For reversible transforms, this factor is guaranteed to be equal to 1.0. For irreversible transforms, the scale factor is computed so as to ensure that the DC gain of the low-pass analysis kernel is equal to 1.0.
Similar to dc_scale, but applied to the high-pass subband. For reversible transforms the factor is guaranteed to be 1.0, while for irreversible transforms, it is computed so as to ensure that the gain of the high-pass analysis kernel at the Nyquist frequency is equal to 1.0.
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