michael@0: /***********************************************************************
michael@0: Copyright (c) 2006-2011, Skype Limited. All rights reserved.
michael@0: Redistribution and use in source and binary forms, with or without
michael@0: modification, are permitted provided that the following conditions
michael@0: are met:
michael@0: - Redistributions of source code must retain the above copyright notice,
michael@0: this list of conditions and the following disclaimer.
michael@0: - Redistributions in binary form must reproduce the above copyright
michael@0: notice, this list of conditions and the following disclaimer in the
michael@0: documentation and/or other materials provided with the distribution.
michael@0: - Neither the name of Internet Society, IETF or IETF Trust, nor the
michael@0: names of specific contributors, may be used to endorse or promote
michael@0: products derived from this software without specific prior written
michael@0: permission.
michael@0: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
michael@0: AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
michael@0: IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
michael@0: ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
michael@0: LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
michael@0: CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
michael@0: SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
michael@0: INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
michael@0: CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0: ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
michael@0: POSSIBILITY OF SUCH DAMAGE.
michael@0: ***********************************************************************/
michael@0: 
michael@0: #ifdef HAVE_CONFIG_H
michael@0: #include "config.h"
michael@0: #endif
michael@0: 
michael@0: /**********************************************************************
michael@0:  * Correlation matrix computations for LS estimate.
michael@0:  **********************************************************************/
michael@0: 
michael@0: #include "main_FLP.h"
michael@0: 
michael@0: /* Calculates correlation vector X'*t */
michael@0: void silk_corrVector_FLP(
michael@0:     const silk_float                *x,                                 /* I    x vector [L+order-1] used to create X       */
michael@0:     const silk_float                *t,                                 /* I    Target vector [L]                           */
michael@0:     const opus_int                  L,                                  /* I    Length of vecors                            */
michael@0:     const opus_int                  Order,                              /* I    Max lag for correlation                     */
michael@0:     silk_float                      *Xt                                 /* O    X'*t correlation vector [order]             */
michael@0: )
michael@0: {
michael@0:     opus_int lag;
michael@0:     const silk_float *ptr1;
michael@0: 
michael@0:     ptr1 = &x[ Order - 1 ];                     /* Points to first sample of column 0 of X: X[:,0] */
michael@0:     for( lag = 0; lag < Order; lag++ ) {
michael@0:         /* Calculate X[:,lag]'*t */
michael@0:         Xt[ lag ] = (silk_float)silk_inner_product_FLP( ptr1, t, L );
michael@0:         ptr1--;                                 /* Next column of X */
michael@0:     }
michael@0: }
michael@0: 
michael@0: /* Calculates correlation matrix X'*X */
michael@0: void silk_corrMatrix_FLP(
michael@0:     const silk_float                *x,                                 /* I    x vector [ L+order-1 ] used to create X     */
michael@0:     const opus_int                  L,                                  /* I    Length of vectors                           */
michael@0:     const opus_int                  Order,                              /* I    Max lag for correlation                     */
michael@0:     silk_float                      *XX                                 /* O    X'*X correlation matrix [order x order]     */
michael@0: )
michael@0: {
michael@0:     opus_int j, lag;
michael@0:     double  energy;
michael@0:     const silk_float *ptr1, *ptr2;
michael@0: 
michael@0:     ptr1 = &x[ Order - 1 ];                     /* First sample of column 0 of X */
michael@0:     energy = silk_energy_FLP( ptr1, L );  /* X[:,0]'*X[:,0] */
michael@0:     matrix_ptr( XX, 0, 0, Order ) = ( silk_float )energy;
michael@0:     for( j = 1; j < Order; j++ ) {
michael@0:         /* Calculate X[:,j]'*X[:,j] */
michael@0:         energy += ptr1[ -j ] * ptr1[ -j ] - ptr1[ L - j ] * ptr1[ L - j ];
michael@0:         matrix_ptr( XX, j, j, Order ) = ( silk_float )energy;
michael@0:     }
michael@0: 
michael@0:     ptr2 = &x[ Order - 2 ];                     /* First sample of column 1 of X */
michael@0:     for( lag = 1; lag < Order; lag++ ) {
michael@0:         /* Calculate X[:,0]'*X[:,lag] */
michael@0:         energy = silk_inner_product_FLP( ptr1, ptr2, L );
michael@0:         matrix_ptr( XX, lag, 0, Order ) = ( silk_float )energy;
michael@0:         matrix_ptr( XX, 0, lag, Order ) = ( silk_float )energy;
michael@0:         /* Calculate X[:,j]'*X[:,j + lag] */
michael@0:         for( j = 1; j < ( Order - lag ); j++ ) {
michael@0:             energy += ptr1[ -j ] * ptr2[ -j ] - ptr1[ L - j ] * ptr2[ L - j ];
michael@0:             matrix_ptr( XX, lag + j, j, Order ) = ( silk_float )energy;
michael@0:             matrix_ptr( XX, j, lag + j, Order ) = ( silk_float )energy;
michael@0:         }
michael@0:         ptr2--;                                 /* Next column of X */
michael@0:     }
michael@0: }