C++ (Cpp) silk_A2NLSF_trans_poly示例

示例#1

文件： A2NLSF.c 项目： kode54/Cog

static OPUS_INLINE void silk_A2NLSF_init(
     const opus_int32    *a_Q16,
     opus_int32          *P,
     opus_int32          *Q,
     const opus_int      dd
)
{
    opus_int k;

    /* Convert filter coefs to even and odd polynomials */
    P[dd] = silk_LSHIFT( 1, 16 );
    Q[dd] = silk_LSHIFT( 1, 16 );
    for( k = 0; k < dd; k++ ) {
        P[ k ] = -a_Q16[ dd - k - 1 ] - a_Q16[ dd + k ];    /* Q16 */
        Q[ k ] = -a_Q16[ dd - k - 1 ] + a_Q16[ dd + k ];    /* Q16 */
    }

    /* Divide out zeros as we have that for even filter orders, */
    /* z =  1 is always a root in Q, and                        */
    /* z = -1 is always a root in P                             */
    for( k = dd; k > 0; k-- ) {
        P[ k - 1 ] -= P[ k ];
        Q[ k - 1 ] += Q[ k ];
    }

    /* Transform polynomials from cos(n*f) to cos(f)^n */
    silk_A2NLSF_trans_poly( P, dd );
    silk_A2NLSF_trans_poly( Q, dd );
}

示例#2

文件： A2NLSF.c 项目： oneman/opus-oneman

static inline void silk_A2NLSF_init(
     const opus_int32    *a_Q16,
     opus_int32          *P,
     opus_int32          *Q,
     const opus_int      dd
)
{
    opus_int k;

    /* Convert filter coefs to even and odd polynomials */
    P[dd] = silk_LSHIFT( 1, QPoly );
    Q[dd] = silk_LSHIFT( 1, QPoly );
    for( k = 0; k < dd; k++ ) {
#if( QPoly < 16 )
        P[ k ] = silk_RSHIFT_ROUND( -a_Q16[ dd - k - 1 ] - a_Q16[ dd + k ], 16 - QPoly ); /* QPoly */
        Q[ k ] = silk_RSHIFT_ROUND( -a_Q16[ dd - k - 1 ] + a_Q16[ dd + k ], 16 - QPoly ); /* QPoly */
#elif( Qpoly == 16 )
        P[ k ] = -a_Q16[ dd - k - 1 ] - a_Q16[ dd + k ]; /* QPoly*/
        Q[ k ] = -a_Q16[ dd - k - 1 ] + a_Q16[ dd + k ]; /* QPoly*/
#else
        P[ k ] = silk_LSHIFT( -a_Q16[ dd - k - 1 ] - a_Q16[ dd + k ], QPoly - 16 ); /* QPoly */
        Q[ k ] = silk_LSHIFT( -a_Q16[ dd - k - 1 ] + a_Q16[ dd + k ], QPoly - 16 ); /* QPoly */
#endif
    }

    /* Divide out zeros as we have that for even filter orders, */
    /* z =  1 is always a root in Q, and                        */
    /* z = -1 is always a root in P                             */
    for( k = dd; k > 0; k-- ) {
        P[ k - 1 ] -= P[ k ];
        Q[ k - 1 ] += Q[ k ];
    }

    /* Transform polynomials from cos(n*f) to cos(f)^n */
    silk_A2NLSF_trans_poly( P, dd );
    silk_A2NLSF_trans_poly( Q, dd );
}