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#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include "SigProc_FIX.h"

/* Approximation of 128 * log2() (very close inverse of silk_log2lin()) */

/* Convert input to a log scale */

opus_int32 silk_lin2log(

const opus_int32 inLin /* I input in linear scale */

)

{

opus_int32 lz, frac_Q7;

silk_CLZ_FRAC( inLin, &lz, &frac_Q7 );

/* Piece-wise parabolic approximation */

return silk_ADD_LSHIFT32( silk_SMLAWB( frac_Q7, silk_MUL( frac_Q7, 128 - frac_Q7 ), 179 ), 31 - lz, 7 );

}