libSBRdec/src/HFgen_preFlat.h

/* -----------------------------------------------------------------------------
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----------------------------------------------------------------------------- */

/**************************** SBR decoder library ******************************

   Author(s):   Manuel Jander, Matthias Hildenbrand

   Description: QMF frequency pre whitening for SBR

*******************************************************************************/

#include "common_fix.h"

#ifndef HFGEN_PREFLAT_H
#define HFGEN_PREFLAT_H

#define GAIN_VEC_EXP 6 /* exponent of GainVec[] */

/**
 * \brief Find gain vector to flatten the QMF frequency bands whithout loosing
 * the fine structure.
 * \param[in] sourceBufferReal real part of QMF domain data.
 * \param[in] sourceBufferImag imaginary part of QMF domain data.
 * \param[in] sourceBuffer_e_overlap exponent of sourceBufferReal.
 * \param[in] sourceBuffer_e_current exponent of sourceBufferImag.
 * \param[in] overlap number of overlap samples.
 * \param[out] GainVec array of gain values (one for each QMF band).
 * \param[out] GainVec_exp exponents of GainVec (one for each QMF band).
 * \param[in] numBands number of low bands (k_0).
 * \param[in] startSample time slot start.
 * \param[in] stopSample time slot stop.
 */
void sbrDecoder_calculateGainVec(FIXP_DBL **sourceBufferReal,
                                 FIXP_DBL **sourceBufferImag,
                                 int sourceBuffer_e_overlap,
                                 int sourceBuffer_e_current, int overlap,
                                 FIXP_DBL GainVec[], int GainVec_exp[],
                                 const int numBands, const int startSample,
                                 const int stopSample);

#endif /* __HFGEN_PREFLAT_H */