/*
  * linear least squares model
  *
  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
  *

  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either

  * version 2.1 of the License, or (at your option) any later version.

  *

  * FFmpeg is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  */
 

 #ifndef AVUTIL_LLS_H
 #define AVUTIL_LLS_H

 #include "common.h"
 #include "mem.h"

 #include "version.h"
 

 #define MAX_VARS 32

 #define MAX_VARS_ALIGN FFALIGN(MAX_VARS+1,4)

 //FIXME avoid direct access to LLSModel from outside

 
 /**
  * Linear least squares model.
  */

 typedef struct LLSModel {

     DECLARE_ALIGNED(32, double, covariance[MAX_VARS_ALIGN][MAX_VARS_ALIGN]);
     DECLARE_ALIGNED(32, double, coeff[MAX_VARS][MAX_VARS]);

     double variance[MAX_VARS];

     int indep_count;

     /**
      * Take the outer-product of var[] with itself, and add to the covariance matrix.
      * @param m this context
      * @param var training samples, starting with the value to be predicted

      *            32-byte aligned, and any padding elements must be initialized
      *            (i.e not denormal/nan).

      */

     void (*update_lls)(struct LLSModel *m, const double *var);

     /**
      * Inner product of var[] and the LPC coefs.
      * @param m this context

      * @param var training samples, excluding the value to be predicted. unaligned.

      * @param order lpc order
      */

     double (*evaluate_lls)(struct LLSModel *m, const double *var, int order);

 } LLSModel;

 void avpriv_init_lls(LLSModel *m, int indep_count);
 void ff_init_lls_x86(LLSModel *m);
 void avpriv_solve_lls(LLSModel *m, double threshold, unsigned short min_order);

 #endif /* AVUTIL_LLS_H */