shithub: opus

ref: 0fd8d675f8bf0f43fe25931c5f4b99bfa0db77fb
dir: /silk/fixed/silk_corrMatrix_FIX.c/

View raw version
/***********************************************************************
Copyright (c) 2006-2011, Skype Limited. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, (subject to the limitations in the disclaimer below)
are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
- Neither the name of Skype Limited, nor the names of specific
contributors, may be used to endorse or promote products derived from
this software without specific prior written permission.
NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED
BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
***********************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

/**********************************************************************
 * Correlation Matrix Computations for LS estimate.
 **********************************************************************/

#include "silk_main_FIX.h"

/* Calculates correlation vector X'*t */
void silk_corrVector_FIX(
    const opus_int16                 *x,         /* I    x vector [L + order - 1] used to form data matrix X */
    const opus_int16                 *t,         /* I    target vector [L]                                   */
    const opus_int                   L,          /* I    Length of vectors                                   */
    const opus_int                   order,      /* I    Max lag for correlation                             */
    opus_int32                       *Xt,        /* O    Pointer to X'*t correlation vector [order]          */
    const opus_int                   rshifts     /* I    Right shifts of correlations                        */
)
{
    opus_int         lag, i;
    const opus_int16 *ptr1, *ptr2;
    opus_int32       inner_prod;

    ptr1 = &x[ order - 1 ]; /* Points to first sample of column 0 of X: X[:,0] */
    ptr2 = t;
    /* Calculate X'*t */
    if( rshifts > 0 ) {
        /* Right shifting used */
        for( lag = 0; lag < order; lag++ ) {
            inner_prod = 0;
            for( i = 0; i < L; i++ ) {
                inner_prod += SKP_RSHIFT32( SKP_SMULBB( ptr1[ i ], ptr2[i] ), rshifts );
            }
            Xt[ lag ] = inner_prod; /* X[:,lag]'*t */
            ptr1--; /* Go to next column of X */
        }
    } else {
        SKP_assert( rshifts == 0 );
        for( lag = 0; lag < order; lag++ ) {
            Xt[ lag ] = silk_inner_prod_aligned( ptr1, ptr2, L ); /* X[:,lag]'*t */
            ptr1--; /* Go to next column of X */
        }
    }
}

/* Calculates correlation matrix X'*X */
void silk_corrMatrix_FIX(
    const opus_int16                 *x,         /* I    x vector [L + order - 1] used to form data matrix X */
    const opus_int                   L,          /* I    Length of vectors                                   */
    const opus_int                   order,      /* I    Max lag for correlation                             */
    const opus_int                   head_room,  /* I    Desired headroom                                    */
    opus_int32                       *XX,        /* O    Pointer to X'*X correlation matrix [ order x order ]*/
    opus_int                         *rshifts    /* I/O  Right shifts of correlations                        */
)
{
    opus_int         i, j, lag, rshifts_local, head_room_rshifts;
    opus_int32       energy;
    const opus_int16 *ptr1, *ptr2;

    /* Calculate energy to find shift used to fit in 32 bits */
    silk_sum_sqr_shift( &energy, &rshifts_local, x, L + order - 1 );
    /* Add shifts to get the desired head room */
    head_room_rshifts = SKP_max( head_room - silk_CLZ32( energy ), 0 );

    energy = SKP_RSHIFT32( energy, head_room_rshifts );
    rshifts_local += head_room_rshifts;

    /* Calculate energy of first column (0) of X: X[:,0]'*X[:,0] */
    /* Remove contribution of first order - 1 samples */
    for( i = 0; i < order - 1; i++ ) {
        energy -= SKP_RSHIFT32( SKP_SMULBB( x[ i ], x[ i ] ), rshifts_local );
    }
    if( rshifts_local < *rshifts ) {
        /* Adjust energy */
        energy = SKP_RSHIFT32( energy, *rshifts - rshifts_local );
        rshifts_local = *rshifts;
    }

    /* Calculate energy of remaining columns of X: X[:,j]'*X[:,j] */
    /* Fill out the diagonal of the correlation matrix */
    matrix_ptr( XX, 0, 0, order ) = energy;
    ptr1 = &x[ order - 1 ]; /* First sample of column 0 of X */
    for( j = 1; j < order; j++ ) {
        energy = SKP_SUB32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ L - j ], ptr1[ L - j ] ), rshifts_local ) );
        energy = SKP_ADD32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ -j ], ptr1[ -j ] ), rshifts_local ) );
        matrix_ptr( XX, j, j, order ) = energy;
    }

    ptr2 = &x[ order - 2 ]; /* First sample of column 1 of X */
    /* Calculate the remaining elements of the correlation matrix */
    if( rshifts_local > 0 ) {
        /* Right shifting used */
        for( lag = 1; lag < order; lag++ ) {
            /* Inner product of column 0 and column lag: X[:,0]'*X[:,lag] */
            energy = 0;
            for( i = 0; i < L; i++ ) {
                energy += SKP_RSHIFT32( SKP_SMULBB( ptr1[ i ], ptr2[i] ), rshifts_local );
            }
            /* Calculate remaining off diagonal: X[:,j]'*X[:,j + lag] */
            matrix_ptr( XX, lag, 0, order ) = energy;
            matrix_ptr( XX, 0, lag, order ) = energy;
            for( j = 1; j < ( order - lag ); j++ ) {
                energy = SKP_SUB32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ L - j ], ptr2[ L - j ] ), rshifts_local ) );
                energy = SKP_ADD32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ -j ], ptr2[ -j ] ), rshifts_local ) );
                matrix_ptr( XX, lag + j, j, order ) = energy;
                matrix_ptr( XX, j, lag + j, order ) = energy;
            }
            ptr2--; /* Update pointer to first sample of next column (lag) in X */
        }
    } else {
        for( lag = 1; lag < order; lag++ ) {
            /* Inner product of column 0 and column lag: X[:,0]'*X[:,lag] */
            energy = silk_inner_prod_aligned( ptr1, ptr2, L );
            matrix_ptr( XX, lag, 0, order ) = energy;
            matrix_ptr( XX, 0, lag, order ) = energy;
            /* Calculate remaining off diagonal: X[:,j]'*X[:,j + lag] */
            for( j = 1; j < ( order - lag ); j++ ) {
                energy = SKP_SUB32( energy, SKP_SMULBB( ptr1[ L - j ], ptr2[ L - j ] ) );
                energy = SKP_SMLABB( energy, ptr1[ -j ], ptr2[ -j ] );
                matrix_ptr( XX, lag + j, j, order ) = energy;
                matrix_ptr( XX, j, lag + j, order ) = energy;
            }
            ptr2--;/* Update pointer to first sample of next column (lag) in X */
        }
    }
    *rshifts = rshifts_local;
}