Update to 2.0.0 tree from current Fremantle build
[opencv] / src / ml / mlann_mlp.cpp
diff --git a/src/ml/mlann_mlp.cpp b/src/ml/mlann_mlp.cpp
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+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+//  By downloading, copying, installing or using the software you agree to this license.
+//  If you do not agree to this license, do not download, install,
+//  copy or use the software.
+//
+//
+//                        Intel License Agreement
+//
+// Copyright (C) 2000, Intel Corporation, all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+//   * Redistribution's of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//   * Redistribution's 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.
+//
+//   * The name of Intel Corporation may not be used to endorse or promote products
+//     derived from this software without specific prior written permission.
+//
+// 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 Intel Corporation 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.
+//
+//M*/
+
+#include "_ml.h"
+
+CvANN_MLP_TrainParams::CvANN_MLP_TrainParams()
+{
+    term_crit = cvTermCriteria( CV_TERMCRIT_ITER + CV_TERMCRIT_EPS, 1000, 0.01 );
+    train_method = RPROP;
+    bp_dw_scale = bp_moment_scale = 0.1;
+    rp_dw0 = 0.1; rp_dw_plus = 1.2; rp_dw_minus = 0.5;
+    rp_dw_min = FLT_EPSILON; rp_dw_max = 50.;
+}
+
+
+CvANN_MLP_TrainParams::CvANN_MLP_TrainParams( CvTermCriteria _term_crit,
+                                              int _train_method,
+                                              double _param1, double _param2 )
+{
+    term_crit = _term_crit;
+    train_method = _train_method;
+    bp_dw_scale = bp_moment_scale = 0.1;
+    rp_dw0 = 1.; rp_dw_plus = 1.2; rp_dw_minus = 0.5;
+    rp_dw_min = FLT_EPSILON; rp_dw_max = 50.;
+
+    if( train_method == RPROP )
+    {
+        rp_dw0 = _param1;
+        if( rp_dw0 < FLT_EPSILON )
+            rp_dw0 = 1.;
+        rp_dw_min = _param2;
+        rp_dw_min = MAX( rp_dw_min, 0 );
+    }
+    else if( train_method == BACKPROP )
+    {
+        bp_dw_scale = _param1;
+        if( bp_dw_scale <= 0 )
+            bp_dw_scale = 0.1;
+        bp_dw_scale = MAX( bp_dw_scale, 1e-3 );
+        bp_dw_scale = MIN( bp_dw_scale, 1 );
+        bp_moment_scale = _param2;
+        if( bp_moment_scale < 0 )
+            bp_moment_scale = 0.1;
+        bp_moment_scale = MIN( bp_moment_scale, 1 );
+    }
+    else
+        train_method = RPROP;
+}
+
+
+CvANN_MLP_TrainParams::~CvANN_MLP_TrainParams()
+{
+}
+
+
+CvANN_MLP::CvANN_MLP()
+{
+    layer_sizes = wbuf = 0;
+    min_val = max_val = min_val1 = max_val1 = 0.;
+    weights = 0;
+    rng = cvRNG(-1);
+    default_model_name = "my_nn";
+    clear();
+}
+
+
+CvANN_MLP::CvANN_MLP( const CvMat* _layer_sizes,
+                      int _activ_func,
+                      double _f_param1, double _f_param2 )
+{
+    layer_sizes = wbuf = 0;
+    min_val = max_val = min_val1 = max_val1 = 0.;
+    weights = 0;
+    rng = cvRNG(-1);
+    default_model_name = "my_nn";
+    create( _layer_sizes, _activ_func, _f_param1, _f_param2 );
+}
+
+
+CvANN_MLP::~CvANN_MLP()
+{
+    clear();
+}
+
+
+void CvANN_MLP::clear()
+{
+    cvReleaseMat( &layer_sizes );
+    cvReleaseMat( &wbuf );
+    cvFree( &weights );
+    activ_func = SIGMOID_SYM;
+    f_param1 = f_param2 = 1;
+    max_buf_sz = 1 << 12;
+}
+
+
+void CvANN_MLP::set_activ_func( int _activ_func, double _f_param1, double _f_param2 )
+{
+    CV_FUNCNAME( "CvANN_MLP::set_activ_func" );
+
+    __BEGIN__;
+
+    if( _activ_func < 0 || _activ_func > GAUSSIAN )
+        CV_ERROR( CV_StsOutOfRange, "Unknown activation function" );
+
+    activ_func = _activ_func;
+
+    switch( activ_func )
+    {
+    case SIGMOID_SYM:
+        max_val = 0.95; min_val = -max_val;
+        max_val1 = 0.98; min_val1 = -max_val1;
+        if( fabs(_f_param1) < FLT_EPSILON )
+            _f_param1 = 2./3;
+        if( fabs(_f_param2) < FLT_EPSILON )
+            _f_param2 = 1.7159;
+        break;
+    case GAUSSIAN:
+        max_val = 1.; min_val = 0.05;
+        max_val1 = 1.; min_val1 = 0.02;
+        if( fabs(_f_param1) < FLT_EPSILON )
+            _f_param1 = 1.;
+        if( fabs(_f_param2) < FLT_EPSILON )
+            _f_param2 = 1.;
+        break;
+    default:
+        min_val = max_val = min_val1 = max_val1 = 0.;
+        _f_param1 = 1.;
+        _f_param2 = 0.;
+    }
+
+    f_param1 = _f_param1;
+    f_param2 = _f_param2;
+
+    __END__;
+}
+
+
+void CvANN_MLP::init_weights()
+{
+    int i, j, k;
+
+    for( i = 1; i < layer_sizes->cols; i++ )
+    {
+        int n1 = layer_sizes->data.i[i-1];
+        int n2 = layer_sizes->data.i[i];
+        double val = 0, G = n2 > 2 ? 0.7*pow((double)n1,1./(n2-1)) : 1.;
+        double* w = weights[i];
+
+        // initialize weights using Nguyen-Widrow algorithm
+        for( j = 0; j < n2; j++ )
+        {
+            double s = 0;
+            for( k = 0; k <= n1; k++ )
+            {
+                val = cvRandReal(&rng)*2-1.;
+                w[k*n2 + j] = val;
+                s += val;
+            }
+
+            if( i < layer_sizes->cols - 1 )
+            {
+                s = 1./(s - val);
+                for( k = 0; k <= n1; k++ )
+                    w[k*n2 + j] *= s;
+                w[n1*n2 + j] *= G*(-1+j*2./n2);
+            }
+        }
+    }
+}
+
+
+void CvANN_MLP::create( const CvMat* _layer_sizes, int _activ_func,
+                        double _f_param1, double _f_param2 )
+{
+    CV_FUNCNAME( "CvANN_MLP::create" );
+
+    __BEGIN__;
+
+    int i, l_step, l_count, buf_sz = 0;
+    int *l_src, *l_dst;
+
+    clear();
+
+    if( !CV_IS_MAT(_layer_sizes) ||
+        (_layer_sizes->cols != 1 && _layer_sizes->rows != 1) ||
+        CV_MAT_TYPE(_layer_sizes->type) != CV_32SC1 )
+        CV_ERROR( CV_StsBadArg,
+        "The array of layer neuron counters must be an integer vector" );
+
+    CV_CALL( set_activ_func( _activ_func, _f_param1, _f_param2 ));
+
+    l_count = _layer_sizes->rows + _layer_sizes->cols - 1;
+    l_src = _layer_sizes->data.i;
+    l_step = CV_IS_MAT_CONT(_layer_sizes->type) ? 1 :
+                _layer_sizes->step / sizeof(l_src[0]);
+    CV_CALL( layer_sizes = cvCreateMat( 1, l_count, CV_32SC1 ));
+    l_dst = layer_sizes->data.i;
+
+    max_count = 0;
+    for( i = 0; i < l_count; i++ )
+    {
+        int n = l_src[i*l_step];
+        if( n < 1 + (0 < i && i < l_count-1))
+            CV_ERROR( CV_StsOutOfRange,
+            "there should be at least one input and one output "
+            "and every hidden layer must have more than 1 neuron" );
+        l_dst[i] = n;
+        max_count = MAX( max_count, n );
+        if( i > 0 )
+            buf_sz += (l_dst[i-1]+1)*n;
+    }
+
+    buf_sz += (l_dst[0] + l_dst[l_count-1]*2)*2;
+
+    CV_CALL( wbuf = cvCreateMat( 1, buf_sz, CV_64F ));
+    CV_CALL( weights = (double**)cvAlloc( (l_count+1)*sizeof(weights[0]) ));
+
+    weights[0] = wbuf->data.db;
+    weights[1] = weights[0] + l_dst[0]*2;
+    for( i = 1; i < l_count; i++ )
+        weights[i+1] = weights[i] + (l_dst[i-1] + 1)*l_dst[i];
+    weights[l_count+1] = weights[l_count] + l_dst[l_count-1]*2;
+
+    __END__;
+}
+
+
+float CvANN_MLP::predict( const CvMat* _inputs, CvMat* _outputs ) const
+{
+    CV_FUNCNAME( "CvANN_MLP::predict" );
+
+    __BEGIN__;
+
+    double* buf;
+    int i, j, n, dn = 0, l_count, dn0, buf_sz, min_buf_sz;
+
+    if( !layer_sizes )
+        CV_ERROR( CV_StsError, "The network has not been initialized" );
+
+    if( !CV_IS_MAT(_inputs) || !CV_IS_MAT(_outputs) ||
+        !CV_ARE_TYPES_EQ(_inputs,_outputs) ||
+        (CV_MAT_TYPE(_inputs->type) != CV_32FC1 &&
+        CV_MAT_TYPE(_inputs->type) != CV_64FC1) ||
+        _inputs->rows != _outputs->rows )
+        CV_ERROR( CV_StsBadArg, "Both input and output must be floating-point matrices "
+                                "of the same type and have the same number of rows" );
+
+    if( _inputs->cols != layer_sizes->data.i[0] )
+        CV_ERROR( CV_StsBadSize, "input matrix must have the same number of columns as "
+                                 "the number of neurons in the input layer" );
+
+    if( _outputs->cols != layer_sizes->data.i[layer_sizes->cols - 1] )
+        CV_ERROR( CV_StsBadSize, "output matrix must have the same number of columns as "
+                                 "the number of neurons in the output layer" );
+    n = dn0 = _inputs->rows;
+    min_buf_sz = 2*max_count;
+    buf_sz = n*min_buf_sz;
+
+    if( buf_sz > max_buf_sz )
+    {
+        dn0 = max_buf_sz/min_buf_sz;
+        dn0 = MAX( dn0, 1 );
+        buf_sz = dn0*min_buf_sz;
+    }
+
+    buf = (double*)cvStackAlloc( buf_sz*sizeof(buf[0]) );
+    l_count = layer_sizes->cols;
+
+    for( i = 0; i < n; i += dn )
+    {
+        CvMat hdr[2], _w, *layer_in = &hdr[0], *layer_out = &hdr[1], *temp;
+        dn = MIN( dn0, n - i );
+
+        cvGetRows( _inputs, layer_in, i, i + dn );
+        cvInitMatHeader( layer_out, dn, layer_in->cols, CV_64F, buf );
+
+        scale_input( layer_in, layer_out );
+        CV_SWAP( layer_in, layer_out, temp );
+
+        for( j = 1; j < l_count; j++ )
+        {
+            double* data = buf + (j&1 ? max_count*dn0 : 0);
+            int cols = layer_sizes->data.i[j];
+
+            cvInitMatHeader( layer_out, dn, cols, CV_64F, data );
+            cvInitMatHeader( &_w, layer_in->cols, layer_out->cols, CV_64F, weights[j] );
+            cvGEMM( layer_in, &_w, 1, 0, 0, layer_out );
+            calc_activ_func( layer_out, _w.data.db + _w.rows*_w.cols );
+
+            CV_SWAP( layer_in, layer_out, temp );
+        }
+
+        cvGetRows( _outputs, layer_out, i, i + dn );
+        scale_output( layer_in, layer_out );
+    }
+
+    __END__;
+
+    return 0.f;
+}
+
+
+void CvANN_MLP::scale_input( const CvMat* _src, CvMat* _dst ) const
+{
+    int i, j, cols = _src->cols;
+    double* dst = _dst->data.db;
+    const double* w = weights[0];
+    int step = _src->step;
+
+    if( CV_MAT_TYPE( _src->type ) == CV_32F )
+    {
+        const float* src = _src->data.fl;
+        step /= sizeof(src[0]);
+
+        for( i = 0; i < _src->rows; i++, src += step, dst += cols )
+            for( j = 0; j < cols; j++ )
+                dst[j] = src[j]*w[j*2] + w[j*2+1];
+    }
+    else
+    {
+        const double* src = _src->data.db;
+        step /= sizeof(src[0]);
+
+        for( i = 0; i < _src->rows; i++, src += step, dst += cols )
+            for( j = 0; j < cols; j++ )
+                dst[j] = src[j]*w[j*2] + w[j*2+1];
+    }
+}
+
+
+void CvANN_MLP::scale_output( const CvMat* _src, CvMat* _dst ) const
+{
+    int i, j, cols = _src->cols;
+    const double* src = _src->data.db;
+    const double* w = weights[layer_sizes->cols];
+    int step = _dst->step;
+
+    if( CV_MAT_TYPE( _dst->type ) == CV_32F )
+    {
+        float* dst = _dst->data.fl;
+        step /= sizeof(dst[0]);
+
+        for( i = 0; i < _src->rows; i++, src += cols, dst += step )
+            for( j = 0; j < cols; j++ )
+                dst[j] = (float)(src[j]*w[j*2] + w[j*2+1]);
+    }
+    else
+    {
+        double* dst = _dst->data.db;
+        step /= sizeof(dst[0]);
+
+        for( i = 0; i < _src->rows; i++, src += cols, dst += step )
+            for( j = 0; j < cols; j++ )
+                dst[j] = src[j]*w[j*2] + w[j*2+1];
+    }
+}
+
+
+void CvANN_MLP::calc_activ_func( CvMat* sums, const double* bias ) const
+{
+    int i, j, n = sums->rows, cols = sums->cols;
+    double* data = sums->data.db;
+    double scale = 0, scale2 = f_param2;
+
+    switch( activ_func )
+    {
+    case IDENTITY:
+        scale = 1.;
+        break;
+    case SIGMOID_SYM:
+        scale = -f_param1;
+        break;
+    case GAUSSIAN:
+        scale = -f_param1*f_param1;
+        break;
+    default:
+        ;
+    }
+
+    assert( CV_IS_MAT_CONT(sums->type) );
+
+    if( activ_func != GAUSSIAN )
+    {
+        for( i = 0; i < n; i++, data += cols )
+            for( j = 0; j < cols; j++ )
+                data[j] = (data[j] + bias[j])*scale;
+
+        if( activ_func == IDENTITY )
+            return;
+    }
+    else
+    {
+        for( i = 0; i < n; i++, data += cols )
+            for( j = 0; j < cols; j++ )
+            {
+                double t = data[j] + bias[j];
+                data[j] = t*t*scale;
+            }
+    }
+
+    cvExp( sums, sums );
+
+    n *= cols;
+    data -= n;
+
+    switch( activ_func )
+    {
+    case SIGMOID_SYM:
+        for( i = 0; i <= n - 4; i += 4 )
+        {
+            double x0 = 1.+data[i], x1 = 1.+data[i+1], x2 = 1.+data[i+2], x3 = 1.+data[i+3];
+            double a = x0*x1, b = x2*x3, d = scale2/(a*b), t0, t1;
+            a *= d; b *= d;
+            t0 = (2 - x0)*b*x1; t1 = (2 - x1)*b*x0;
+            data[i] = t0; data[i+1] = t1;
+            t0 = (2 - x2)*a*x3; t1 = (2 - x3)*a*x2;
+            data[i+2] = t0; data[i+3] = t1;
+        }
+
+        for( ; i < n; i++ )
+        {
+            double t = scale2*(1. - data[i])/(1. + data[i]);
+            data[i] = t;
+        }
+        break;
+
+    case GAUSSIAN:
+        for( i = 0; i < n; i++ )
+            data[i] = scale2*data[i];
+        break;
+
+    default:
+        ;
+    }
+}
+
+
+void CvANN_MLP::calc_activ_func_deriv( CvMat* _xf, CvMat* _df,
+                                       const double* bias ) const
+{
+    int i, j, n = _xf->rows, cols = _xf->cols;
+    double* xf = _xf->data.db;
+    double* df = _df->data.db;
+    double scale, scale2 = f_param2;
+    assert( CV_IS_MAT_CONT( _xf->type & _df->type ) );
+
+    if( activ_func == IDENTITY )
+    {
+        for( i = 0; i < n; i++, xf += cols, df += cols )
+            for( j = 0; j < cols; j++ )
+            {
+                xf[j] += bias[j];
+                df[j] = 1;
+            }
+        return;
+    }
+    else if( activ_func == GAUSSIAN )
+    {
+        scale = -f_param1*f_param1;
+        scale2 *= scale;
+        for( i = 0; i < n; i++, xf += cols, df += cols )
+            for( j = 0; j < cols; j++ )
+            {
+                double t = xf[j] + bias[j];
+                df[j] = t*2*scale2;
+                xf[j] = t*t*scale;
+            }
+    }
+    else
+    {
+        scale = -f_param1;
+        for( i = 0; i < n; i++, xf += cols, df += cols )
+            for( j = 0; j < cols; j++ )
+                xf[j] = (xf[j] + bias[j])*scale;
+    }
+
+    cvExp( _xf, _xf );
+
+    n *= cols;
+    xf -= n; df -= n;
+
+    // ((1+exp(-ax))^-1)'=a*((1+exp(-ax))^-2)*exp(-ax);
+    // ((1-exp(-ax))/(1+exp(-ax)))'=(a*exp(-ax)*(1+exp(-ax)) + a*exp(-ax)*(1-exp(-ax)))/(1+exp(-ax))^2=
+    // 2*a*exp(-ax)/(1+exp(-ax))^2
+    switch( activ_func )
+    {
+    case SIGMOID_SYM:
+        scale *= -2*f_param2;
+        for( i = 0; i <= n - 4; i += 4 )
+        {
+            double x0 = 1.+xf[i], x1 = 1.+xf[i+1], x2 = 1.+xf[i+2], x3 = 1.+xf[i+3];
+            double a = x0*x1, b = x2*x3, d = 1./(a*b), t0, t1;
+            a *= d; b *= d;
+
+            t0 = b*x1; t1 = b*x0;
+            df[i] = scale*xf[i]*t0*t0;
+            df[i+1] = scale*xf[i+1]*t1*t1;
+            t0 *= scale2*(2 - x0); t1 *= scale2*(2 - x1);
+            xf[i] = t0; xf[i+1] = t1;
+
+            t0 = a*x3; t1 = a*x2;
+            df[i+2] = scale*xf[i+2]*t0*t0;
+            df[i+3] = scale*xf[i+3]*t1*t1;
+            t0 *= scale2*(2 - x2); t1 *= scale2*(2 - x3);
+            xf[i+2] = t0; xf[i+3] = t1;
+        }
+
+        for( ; i < n; i++ )
+        {
+            double t0 = 1./(1. + xf[i]);
+            double t1 = scale*xf[i]*t0*t0;
+            t0 *= scale2*(1. - xf[i]);
+            df[i] = t1;
+            xf[i] = t0;
+        }
+        break;
+
+    case GAUSSIAN:
+        for( i = 0; i < n; i++ )
+            df[i] *= xf[i];
+        break;
+    default:
+        ;
+    }
+}
+
+
+void CvANN_MLP::calc_input_scale( const CvVectors* vecs, int flags )
+{
+    bool reset_weights = (flags & UPDATE_WEIGHTS) == 0;
+    bool no_scale = (flags & NO_INPUT_SCALE) != 0;
+    double* scale = weights[0];
+    int count = vecs->count;
+
+    if( reset_weights )
+    {
+        int i, j, vcount = layer_sizes->data.i[0];
+        int type = vecs->type;
+        double a = no_scale ? 1. : 0.;
+
+        for( j = 0; j < vcount; j++ )
+            scale[2*j] = a, scale[j*2+1] = 0.;
+
+        if( no_scale )
+            return;
+
+        for( i = 0; i < count; i++ )
+        {
+            const float* f = vecs->data.fl[i];
+            const double* d = vecs->data.db[i];
+            for( j = 0; j < vcount; j++ )
+            {
+                double t = type == CV_32F ? (double)f[j] : d[j];
+                scale[j*2] += t;
+                scale[j*2+1] += t*t;
+            }
+        }
+
+        for( j = 0; j < vcount; j++ )
+        {
+            double s = scale[j*2], s2 = scale[j*2+1];
+            double m = s/count, sigma2 = s2/count - m*m;
+            scale[j*2] = sigma2 < DBL_EPSILON ? 1 : 1./sqrt(sigma2);
+            scale[j*2+1] = -m*scale[j*2];
+        }
+    }
+}
+
+
+void CvANN_MLP::calc_output_scale( const CvVectors* vecs, int flags )
+{
+    int i, j, vcount = layer_sizes->data.i[layer_sizes->cols-1];
+    int type = vecs->type;
+    double m = min_val, M = max_val, m1 = min_val1, M1 = max_val1;
+    bool reset_weights = (flags & UPDATE_WEIGHTS) == 0;
+    bool no_scale = (flags & NO_OUTPUT_SCALE) != 0;
+    int l_count = layer_sizes->cols;
+    double* scale = weights[l_count];
+    double* inv_scale = weights[l_count+1];
+    int count = vecs->count;
+
+    CV_FUNCNAME( "CvANN_MLP::calc_output_scale" );
+
+    __BEGIN__;
+
+    if( reset_weights )
+    {
+        double a0 = no_scale ? 1 : DBL_MAX, b0 = no_scale ? 0 : -DBL_MAX;
+
+        for( j = 0; j < vcount; j++ )
+        {
+            scale[2*j] = inv_scale[2*j] = a0;
+            scale[j*2+1] = inv_scale[2*j+1] = b0;
+        }
+
+        if( no_scale )
+            EXIT;
+    }
+
+    for( i = 0; i < count; i++ )
+    {
+        const float* f = vecs->data.fl[i];
+        const double* d = vecs->data.db[i];
+
+        for( j = 0; j < vcount; j++ )
+        {
+            double t = type == CV_32F ? (double)f[j] : d[j];
+
+            if( reset_weights )
+            {
+                double mj = scale[j*2], Mj = scale[j*2+1];
+                if( mj > t ) mj = t;
+                if( Mj < t ) Mj = t;
+
+                scale[j*2] = mj;
+                scale[j*2+1] = Mj;
+            }
+            else
+            {
+                t = t*scale[j*2] + scale[2*j+1];
+                if( t < m1 || t > M1 )
+                    CV_ERROR( CV_StsOutOfRange,
+                    "Some of new output training vector components run exceed the original range too much" );
+            }
+        }
+    }
+
+    if( reset_weights )
+        for( j = 0; j < vcount; j++ )
+        {
+            // map mj..Mj to m..M
+            double mj = scale[j*2], Mj = scale[j*2+1];
+            double a, b;
+            double delta = Mj - mj;
+            if( delta < DBL_EPSILON )
+                a = 1, b = (M + m - Mj - mj)*0.5;
+            else
+                a = (M - m)/delta, b = m - mj*a;
+            inv_scale[j*2] = a; inv_scale[j*2+1] = b;
+            a = 1./a; b = -b*a;
+            scale[j*2] = a; scale[j*2+1] = b;
+        }
+
+    __END__;
+}
+
+
+bool CvANN_MLP::prepare_to_train( const CvMat* _inputs, const CvMat* _outputs,
+            const CvMat* _sample_weights, const CvMat* _sample_idx,
+            CvVectors* _ivecs, CvVectors* _ovecs, double** _sw, int _flags )
+{
+    bool ok = false;
+    CvMat* sample_idx = 0;
+    CvVectors ivecs, ovecs;
+    double* sw = 0;
+    int count = 0;
+
+    CV_FUNCNAME( "CvANN_MLP::prepare_to_train" );
+
+    ivecs.data.ptr = ovecs.data.ptr = 0;
+    assert( _ivecs && _ovecs );
+
+    __BEGIN__;
+
+    const int* sidx = 0;
+    int i, sw_type = 0, sw_count = 0;
+    int sw_step = 0;
+    double sw_sum = 0;
+
+    if( !layer_sizes )
+        CV_ERROR( CV_StsError,
+        "The network has not been created. Use method create or the appropriate constructor" );
+
+    if( !CV_IS_MAT(_inputs) || (CV_MAT_TYPE(_inputs->type) != CV_32FC1 &&
+        CV_MAT_TYPE(_inputs->type) != CV_64FC1) || _inputs->cols != layer_sizes->data.i[0] )
+        CV_ERROR( CV_StsBadArg,
+        "input training data should be a floating-point matrix with"
+        "the number of rows equal to the number of training samples and "
+        "the number of columns equal to the size of 0-th (input) layer" );
+
+    if( !CV_IS_MAT(_outputs) || (CV_MAT_TYPE(_outputs->type) != CV_32FC1 &&
+        CV_MAT_TYPE(_outputs->type) != CV_64FC1) ||
+        _outputs->cols != layer_sizes->data.i[layer_sizes->cols - 1] )
+        CV_ERROR( CV_StsBadArg,
+        "output training data should be a floating-point matrix with"
+        "the number of rows equal to the number of training samples and "
+        "the number of columns equal to the size of last (output) layer" );
+
+    if( _inputs->rows != _outputs->rows )
+        CV_ERROR( CV_StsUnmatchedSizes, "The numbers of input and output samples do not match" );
+
+    if( _sample_idx )
+    {
+        CV_CALL( sample_idx = cvPreprocessIndexArray( _sample_idx, _inputs->rows ));
+        sidx = sample_idx->data.i;
+        count = sample_idx->cols + sample_idx->rows - 1;
+    }
+    else
+        count = _inputs->rows;
+
+    if( _sample_weights )
+    {
+        if( !CV_IS_MAT(_sample_weights) )
+            CV_ERROR( CV_StsBadArg, "sample_weights (if passed) must be a valid matrix" );
+
+        sw_type = CV_MAT_TYPE(_sample_weights->type);
+        sw_count = _sample_weights->cols + _sample_weights->rows - 1;
+
+        if( (sw_type != CV_32FC1 && sw_type != CV_64FC1) ||
+            (_sample_weights->cols != 1 && _sample_weights->rows != 1) ||
+            (sw_count != count && sw_count != _inputs->rows) )
+            CV_ERROR( CV_StsBadArg,
+            "sample_weights must be 1d floating-point vector containing weights "
+            "of all or selected training samples" );
+
+        sw_step = CV_IS_MAT_CONT(_sample_weights->type) ? 1 :
+            _sample_weights->step/CV_ELEM_SIZE(sw_type);
+
+        CV_CALL( sw = (double*)cvAlloc( count*sizeof(sw[0]) ));
+    }
+
+    CV_CALL( ivecs.data.ptr = (uchar**)cvAlloc( count*sizeof(ivecs.data.ptr[0]) ));
+    CV_CALL( ovecs.data.ptr = (uchar**)cvAlloc( count*sizeof(ovecs.data.ptr[0]) ));
+
+    ivecs.type = CV_MAT_TYPE(_inputs->type);
+    ovecs.type = CV_MAT_TYPE(_outputs->type);
+    ivecs.count = ovecs.count = count;
+
+    for( i = 0; i < count; i++ )
+    {
+        int idx = sidx ? sidx[i] : i;
+        ivecs.data.ptr[i] = _inputs->data.ptr + idx*_inputs->step;
+        ovecs.data.ptr[i] = _outputs->data.ptr + idx*_outputs->step;
+        if( sw )
+        {
+            int si = sw_count == count ? i : idx;
+            double w = sw_type == CV_32FC1 ?
+                (double)_sample_weights->data.fl[si*sw_step] :
+                _sample_weights->data.db[si*sw_step];
+            sw[i] = w;
+            if( w < 0 )
+                CV_ERROR( CV_StsOutOfRange, "some of sample weights are negative" );
+            sw_sum += w;
+        }
+    }
+
+    // normalize weights
+    if( sw )
+    {
+        sw_sum = sw_sum > DBL_EPSILON ? 1./sw_sum : 0;
+        for( i = 0; i < count; i++ )
+            sw[i] *= sw_sum;
+    }
+
+    calc_input_scale( &ivecs, _flags );
+    CV_CALL( calc_output_scale( &ovecs, _flags ));
+
+    ok = true;
+
+    __END__;
+
+    if( !ok )
+    {
+        cvFree( &ivecs.data.ptr );
+        cvFree( &ovecs.data.ptr );
+        cvFree( &sw );
+    }
+
+    cvReleaseMat( &sample_idx );
+    *_ivecs = ivecs;
+    *_ovecs = ovecs;
+    *_sw = sw;
+
+    return ok;
+}
+
+
+int CvANN_MLP::train( const CvMat* _inputs, const CvMat* _outputs,
+                      const CvMat* _sample_weights, const CvMat* _sample_idx,
+                      CvANN_MLP_TrainParams _params, int flags )
+{
+    const int MAX_ITER = 1000;
+    const double DEFAULT_EPSILON = FLT_EPSILON;
+
+    double* sw = 0;
+    CvVectors x0, u;
+    int iter = -1;
+
+    x0.data.ptr = u.data.ptr = 0;
+
+    CV_FUNCNAME( "CvANN_MLP::train" );
+
+    __BEGIN__;
+
+    int max_iter;
+    double epsilon;
+
+    params = _params;
+
+    // initialize training data
+    CV_CALL( prepare_to_train( _inputs, _outputs, _sample_weights,
+                               _sample_idx, &x0, &u, &sw, flags ));
+
+    // ... and link weights
+    if( !(flags & UPDATE_WEIGHTS) )
+        init_weights();
+
+    max_iter = params.term_crit.type & CV_TERMCRIT_ITER ? params.term_crit.max_iter : MAX_ITER;
+    max_iter = MIN( max_iter, MAX_ITER );
+    max_iter = MAX( max_iter, 1 );
+
+    epsilon = params.term_crit.type & CV_TERMCRIT_EPS ? params.term_crit.epsilon : DEFAULT_EPSILON;
+    epsilon = MAX(epsilon, DBL_EPSILON);
+
+    params.term_crit.type = CV_TERMCRIT_ITER + CV_TERMCRIT_EPS;
+    params.term_crit.max_iter = max_iter;
+    params.term_crit.epsilon = epsilon;
+
+    if( params.train_method == CvANN_MLP_TrainParams::BACKPROP )
+    {
+        CV_CALL( iter = train_backprop( x0, u, sw ));
+    }
+    else
+    {
+        CV_CALL( iter = train_rprop( x0, u, sw ));
+    }
+
+    __END__;
+
+    cvFree( &x0.data.ptr );
+    cvFree( &u.data.ptr );
+    cvFree( &sw );
+
+    return iter;
+}
+
+
+int CvANN_MLP::train_backprop( CvVectors x0, CvVectors u, const double* sw )
+{
+    CvMat* dw = 0;
+    CvMat* buf = 0;
+    double **x = 0, **df = 0;
+    CvMat* _idx = 0;
+    int iter = -1, count = x0.count;
+
+    CV_FUNCNAME( "CvANN_MLP::train_backprop" );
+
+    __BEGIN__;
+
+    int i, j, k, ivcount, ovcount, l_count, total = 0, max_iter;
+    double *buf_ptr;
+    double prev_E = DBL_MAX*0.5, E = 0, epsilon;
+
+    max_iter = params.term_crit.max_iter*count;
+    epsilon = params.term_crit.epsilon*count;
+
+    l_count = layer_sizes->cols;
+    ivcount = layer_sizes->data.i[0];
+    ovcount = layer_sizes->data.i[l_count-1];
+
+    // allocate buffers
+    for( i = 0; i < l_count; i++ )
+        total += layer_sizes->data.i[i] + 1;
+
+    CV_CALL( dw = cvCreateMat( wbuf->rows, wbuf->cols, wbuf->type ));
+    cvZero( dw );
+    CV_CALL( buf = cvCreateMat( 1, (total + max_count)*2, CV_64F ));
+    CV_CALL( _idx = cvCreateMat( 1, count, CV_32SC1 ));
+    for( i = 0; i < count; i++ )
+        _idx->data.i[i] = i;
+
+    CV_CALL( x = (double**)cvAlloc( total*2*sizeof(x[0]) ));
+    df = x + total;
+    buf_ptr = buf->data.db;
+
+    for( j = 0; j < l_count; j++ )
+    {
+        x[j] = buf_ptr;
+        df[j] = x[j] + layer_sizes->data.i[j];
+        buf_ptr += (df[j] - x[j])*2;
+    }
+
+    // run back-propagation loop
+    /*
+        y_i = w_i*x_{i-1}
+        x_i = f(y_i)
+        E = 1/2*||u - x_N||^2
+        grad_N = (x_N - u)*f'(y_i)
+        dw_i(t) = momentum*dw_i(t-1) + dw_scale*x_{i-1}*grad_i
+        w_i(t+1) = w_i(t) + dw_i(t)
+        grad_{i-1} = w_i^t*grad_i
+    */
+    for( iter = 0; iter < max_iter; iter++ )
+    {
+        int idx = iter % count;
+        double* w = weights[0];
+        double sweight = sw ? count*sw[idx] : 1.;
+        CvMat _w, _dw, hdr1, hdr2, ghdr1, ghdr2, _df;
+        CvMat *x1 = &hdr1, *x2 = &hdr2, *grad1 = &ghdr1, *grad2 = &ghdr2, *temp;
+
+        if( idx == 0 )
+        {
+            if( fabs(prev_E - E) < epsilon )
+                break;
+            prev_E = E;
+            E = 0;
+
+            // shuffle indices
+            for( i = 0; i < count; i++ )
+            {
+                int tt;
+                j = (unsigned)cvRandInt(&rng) % count;
+                k = (unsigned)cvRandInt(&rng) % count;
+                CV_SWAP( _idx->data.i[j], _idx->data.i[k], tt );
+            }
+        }
+
+        idx = _idx->data.i[idx];
+
+        if( x0.type == CV_32F )
+        {
+            const float* x0data = x0.data.fl[idx];
+            for( j = 0; j < ivcount; j++ )
+                x[0][j] = x0data[j]*w[j*2] + w[j*2 + 1];
+        }
+        else
+        {
+            const double* x0data = x0.data.db[idx];
+            for( j = 0; j < ivcount; j++ )
+                x[0][j] = x0data[j]*w[j*2] + w[j*2 + 1];
+        }
+
+        cvInitMatHeader( x1, 1, ivcount, CV_64F, x[0] );
+
+        // forward pass, compute y[i]=w*x[i-1], x[i]=f(y[i]), df[i]=f'(y[i])
+        for( i = 1; i < l_count; i++ )
+        {
+            cvInitMatHeader( x2, 1, layer_sizes->data.i[i], CV_64F, x[i] );
+            cvInitMatHeader( &_w, x1->cols, x2->cols, CV_64F, weights[i] );
+            cvGEMM( x1, &_w, 1, 0, 0, x2 );
+            _df = *x2;
+            _df.data.db = df[i];
+            calc_activ_func_deriv( x2, &_df, _w.data.db + _w.rows*_w.cols );
+            CV_SWAP( x1, x2, temp );
+        }
+
+        cvInitMatHeader( grad1, 1, ovcount, CV_64F, buf_ptr );
+        *grad2 = *grad1;
+        grad2->data.db = buf_ptr + max_count;
+
+        w = weights[l_count+1];
+
+        // calculate error
+        if( u.type == CV_32F )
+        {
+            const float* udata = u.data.fl[idx];
+            for( k = 0; k < ovcount; k++ )
+            {
+                double t = udata[k]*w[k*2] + w[k*2+1] - x[l_count-1][k];
+                grad1->data.db[k] = t*sweight;
+                E += t*t;
+            }
+        }
+        else
+        {
+            const double* udata = u.data.db[idx];
+            for( k = 0; k < ovcount; k++ )
+            {
+                double t = udata[k]*w[k*2] + w[k*2+1] - x[l_count-1][k];
+                grad1->data.db[k] = t*sweight;
+                E += t*t;
+            }
+        }
+        E *= sweight;
+
+        // backward pass, update weights
+        for( i = l_count-1; i > 0; i-- )
+        {
+            int n1 = layer_sizes->data.i[i-1], n2 = layer_sizes->data.i[i];
+            cvInitMatHeader( &_df, 1, n2, CV_64F, df[i] );
+            cvMul( grad1, &_df, grad1 );
+            cvInitMatHeader( &_w, n1+1, n2, CV_64F, weights[i] );
+            cvInitMatHeader( &_dw, n1+1, n2, CV_64F, dw->data.db + (weights[i] - weights[0]) );
+            cvInitMatHeader( x1, n1+1, 1, CV_64F, x[i-1] );
+            x[i-1][n1] = 1.;
+            cvGEMM( x1, grad1, params.bp_dw_scale, &_dw, params.bp_moment_scale, &_dw );
+            cvAdd( &_w, &_dw, &_w );
+            if( i > 1 )
+            {
+                grad2->cols = n1;
+                _w.rows = n1;
+                cvGEMM( grad1, &_w, 1, 0, 0, grad2, CV_GEMM_B_T );
+            }
+            CV_SWAP( grad1, grad2, temp );
+        }
+    }
+
+    iter /= count;
+
+    __END__;
+
+    cvReleaseMat( &dw );
+    cvReleaseMat( &buf );
+    cvReleaseMat( &_idx );
+    cvFree( &x );
+
+    return iter;
+}
+
+
+int CvANN_MLP::train_rprop( CvVectors x0, CvVectors u, const double* sw )
+{
+    const int max_buf_sz = 1 << 16;
+    CvMat* dw = 0;
+    CvMat* dEdw = 0;
+    CvMat* prev_dEdw_sign = 0;
+    CvMat* buf = 0;
+    double **x = 0, **df = 0;
+    int iter = -1, count = x0.count;
+
+    CV_FUNCNAME( "CvANN_MLP::train" );
+
+    __BEGIN__;
+
+    int i, ivcount, ovcount, l_count, total = 0, max_iter, buf_sz, dcount0, dcount=0;
+    double *buf_ptr;
+    double prev_E = DBL_MAX*0.5, epsilon;
+    double dw_plus, dw_minus, dw_min, dw_max;
+    double inv_count;
+
+    max_iter = params.term_crit.max_iter;
+    epsilon = params.term_crit.epsilon;
+    dw_plus = params.rp_dw_plus;
+    dw_minus = params.rp_dw_minus;
+    dw_min = params.rp_dw_min;
+    dw_max = params.rp_dw_max;
+
+    l_count = layer_sizes->cols;
+    ivcount = layer_sizes->data.i[0];
+    ovcount = layer_sizes->data.i[l_count-1];
+
+    // allocate buffers
+    for( i = 0; i < l_count; i++ )
+        total += layer_sizes->data.i[i];
+
+    CV_CALL( dw = cvCreateMat( wbuf->rows, wbuf->cols, wbuf->type ));
+    cvSet( dw, cvScalarAll(params.rp_dw0) );
+    CV_CALL( dEdw = cvCreateMat( wbuf->rows, wbuf->cols, wbuf->type ));
+    cvZero( dEdw );
+    CV_CALL( prev_dEdw_sign = cvCreateMat( wbuf->rows, wbuf->cols, CV_8SC1 ));
+    cvZero( prev_dEdw_sign );
+
+    inv_count = 1./count;
+    dcount0 = max_buf_sz/(2*total);
+    dcount0 = MAX( dcount0, 1 );
+    dcount0 = MIN( dcount0, count );
+    buf_sz = dcount0*(total + max_count)*2;
+
+    CV_CALL( buf = cvCreateMat( 1, buf_sz, CV_64F ));
+
+    CV_CALL( x = (double**)cvAlloc( total*2*sizeof(x[0]) ));
+    df = x + total;
+    buf_ptr = buf->data.db;
+
+    for( i = 0; i < l_count; i++ )
+    {
+        x[i] = buf_ptr;
+        df[i] = x[i] + layer_sizes->data.i[i]*dcount0;
+        buf_ptr += (df[i] - x[i])*2;
+    }
+
+    // run rprop loop
+    /*
+        y_i(t) = w_i(t)*x_{i-1}(t)
+        x_i(t) = f(y_i(t))
+        E = sum_over_all_samples(1/2*||u - x_N||^2)
+        grad_N = (x_N - u)*f'(y_i)
+
+                      MIN(dw_i{jk}(t)*dw_plus, dw_max), if dE/dw_i{jk}(t)*dE/dw_i{jk}(t-1) > 0
+        dw_i{jk}(t) = MAX(dw_i{jk}(t)*dw_minus, dw_min), if dE/dw_i{jk}(t)*dE/dw_i{jk}(t-1) < 0
+                      dw_i{jk}(t-1) else
+
+        if (dE/dw_i{jk}(t)*dE/dw_i{jk}(t-1) < 0)
+           dE/dw_i{jk}(t)<-0
+        else
+           w_i{jk}(t+1) = w_i{jk}(t) + dw_i{jk}(t)
+        grad_{i-1}(t) = w_i^t(t)*grad_i(t)
+    */
+    for( iter = 0; iter < max_iter; iter++ )
+    {
+        int n1, n2, si, j, k;
+        double* w;
+        CvMat _w, _dEdw, hdr1, hdr2, ghdr1, ghdr2, _df;
+        CvMat *x1, *x2, *grad1, *grad2, *temp;
+        double E = 0;
+
+        // first, iterate through all the samples and compute dEdw
+        for( si = 0; si < count; si += dcount )
+        {
+            dcount = MIN( count - si, dcount0 );
+            w = weights[0];
+            grad1 = &ghdr1; grad2 = &ghdr2;
+            x1 = &hdr1; x2 = &hdr2;
+
+            // grab and preprocess input data
+            if( x0.type == CV_32F )
+                for( i = 0; i < dcount; i++ )
+                {
+                    const float* x0data = x0.data.fl[si+i];
+                    double* xdata = x[0]+i*ivcount;
+                    for( j = 0; j < ivcount; j++ )
+                        xdata[j] = x0data[j]*w[j*2] + w[j*2+1];
+                }
+            else
+                for( i = 0; i < dcount; i++ )
+                {
+                    const double* x0data = x0.data.db[si+i];
+                    double* xdata = x[0]+i*ivcount;
+                    for( j = 0; j < ivcount; j++ )
+                        xdata[j] = x0data[j]*w[j*2] + w[j*2+1];
+                }
+
+            cvInitMatHeader( x1, dcount, ivcount, CV_64F, x[0] );
+
+            // forward pass, compute y[i]=w*x[i-1], x[i]=f(y[i]), df[i]=f'(y[i])
+            for( i = 1; i < l_count; i++ )
+            {
+                cvInitMatHeader( x2, dcount, layer_sizes->data.i[i], CV_64F, x[i] );
+                cvInitMatHeader( &_w, x1->cols, x2->cols, CV_64F, weights[i] );
+                cvGEMM( x1, &_w, 1, 0, 0, x2 );
+                _df = *x2;
+                _df.data.db = df[i];
+                calc_activ_func_deriv( x2, &_df, _w.data.db + _w.rows*_w.cols );
+                CV_SWAP( x1, x2, temp );
+            }
+
+            cvInitMatHeader( grad1, dcount, ovcount, CV_64F, buf_ptr );
+            w = weights[l_count+1];
+            grad2->data.db = buf_ptr + max_count*dcount;
+
+            // calculate error
+            if( u.type == CV_32F )
+                for( i = 0; i < dcount; i++ )
+                {
+                    const float* udata = u.data.fl[si+i];
+                    const double* xdata = x[l_count-1] + i*ovcount;
+                    double* gdata = grad1->data.db + i*ovcount;
+                    double sweight = sw ? sw[si+i] : inv_count, E1 = 0;
+
+                    for( j = 0; j < ovcount; j++ )
+                    {
+                        double t = udata[j]*w[j*2] + w[j*2+1] - xdata[j];
+                        gdata[j] = t*sweight;
+                        E1 += t*t;
+                    }
+                    E += sweight*E1;
+                }
+            else
+                for( i = 0; i < dcount; i++ )
+                {
+                    const double* udata = u.data.db[si+i];
+                    const double* xdata = x[l_count-1] + i*ovcount;
+                    double* gdata = grad1->data.db + i*ovcount;
+                    double sweight = sw ? sw[si+i] : inv_count, E1 = 0;
+
+                    for( j = 0; j < ovcount; j++ )
+                    {
+                        double t = udata[j]*w[j*2] + w[j*2+1] - xdata[j];
+                        gdata[j] = t*sweight;
+                        E1 += t*t;
+                    }
+                    E += sweight*E1;
+                }
+
+            // backward pass, update dEdw
+            for( i = l_count-1; i > 0; i-- )
+            {
+                n1 = layer_sizes->data.i[i-1]; n2 = layer_sizes->data.i[i];
+                cvInitMatHeader( &_df, dcount, n2, CV_64F, df[i] );
+                cvMul( grad1, &_df, grad1 );
+                cvInitMatHeader( &_dEdw, n1, n2, CV_64F, dEdw->data.db+(weights[i]-weights[0]) );
+                cvInitMatHeader( x1, dcount, n1, CV_64F, x[i-1] );
+                cvGEMM( x1, grad1, 1, &_dEdw, 1, &_dEdw, CV_GEMM_A_T );
+                // update bias part of dEdw
+                for( k = 0; k < dcount; k++ )
+                {
+                    double* dst = _dEdw.data.db + n1*n2;
+                    const double* src = grad1->data.db + k*n2;
+                    for( j = 0; j < n2; j++ )
+                        dst[j] += src[j];
+                }
+                cvInitMatHeader( &_w, n1, n2, CV_64F, weights[i] );
+                cvInitMatHeader( grad2, dcount, n1, CV_64F, grad2->data.db );
+
+                if( i > 1 )
+                    cvGEMM( grad1, &_w, 1, 0, 0, grad2, CV_GEMM_B_T );
+                CV_SWAP( grad1, grad2, temp );
+            }
+        }
+
+        // now update weights
+        for( i = 1; i < l_count; i++ )
+        {
+            n1 = layer_sizes->data.i[i-1]; n2 = layer_sizes->data.i[i];
+            for( k = 0; k <= n1; k++ )
+            {
+                double* wk = weights[i]+k*n2;
+                size_t delta = wk - weights[0];
+                double* dwk = dw->data.db + delta;
+                double* dEdwk = dEdw->data.db + delta;
+                char* prevEk = (char*)(prev_dEdw_sign->data.ptr + delta);
+
+                for( j = 0; j < n2; j++ )
+                {
+                    double Eval = dEdwk[j];
+                    double dval = dwk[j];
+                    double wval = wk[j];
+                    int s = CV_SIGN(Eval);
+                    int ss = prevEk[j]*s;
+                    if( ss > 0 )
+                    {
+                        dval *= dw_plus;
+                        dval = MIN( dval, dw_max );
+                        dwk[j] = dval;
+                        wk[j] = wval + dval*s;
+                    }
+                    else if( ss < 0 )
+                    {
+                        dval *= dw_minus;
+                        dval = MAX( dval, dw_min );
+                        prevEk[j] = 0;
+                        dwk[j] = dval;
+                        wk[j] = wval + dval*s;
+                    }
+                    else
+                    {
+                        prevEk[j] = (char)s;
+                        wk[j] = wval + dval*s;
+                    }
+                    dEdwk[j] = 0.;
+                }
+            }
+        }
+
+        if( fabs(prev_E - E) < epsilon )
+            break;
+        prev_E = E;
+        E = 0;
+    }
+
+    __END__;
+
+    cvReleaseMat( &dw );
+    cvReleaseMat( &dEdw );
+    cvReleaseMat( &prev_dEdw_sign );
+    cvReleaseMat( &buf );
+    cvFree( &x );
+
+    return iter;
+}
+
+
+void CvANN_MLP::write_params( CvFileStorage* fs ) const
+{
+    //CV_FUNCNAME( "CvANN_MLP::write_params" );
+
+    __BEGIN__;
+
+    const char* activ_func_name = activ_func == IDENTITY ? "IDENTITY" :
+                            activ_func == SIGMOID_SYM ? "SIGMOID_SYM" :
+                            activ_func == GAUSSIAN ? "GAUSSIAN" : 0;
+
+    if( activ_func_name )
+        cvWriteString( fs, "activation_function", activ_func_name );
+    else
+        cvWriteInt( fs, "activation_function", activ_func );
+
+    if( activ_func != IDENTITY )
+    {
+        cvWriteReal( fs, "f_param1", f_param1 );
+        cvWriteReal( fs, "f_param2", f_param2 );
+    }
+
+    cvWriteReal( fs, "min_val", min_val );
+    cvWriteReal( fs, "max_val", max_val );
+    cvWriteReal( fs, "min_val1", min_val1 );
+    cvWriteReal( fs, "max_val1", max_val1 );
+
+    cvStartWriteStruct( fs, "training_params", CV_NODE_MAP );
+    if( params.train_method == CvANN_MLP_TrainParams::BACKPROP )
+    {
+        cvWriteString( fs, "train_method", "BACKPROP" );
+        cvWriteReal( fs, "dw_scale", params.bp_dw_scale );
+        cvWriteReal( fs, "moment_scale", params.bp_moment_scale );
+    }
+    else if( params.train_method == CvANN_MLP_TrainParams::RPROP )
+    {
+        cvWriteString( fs, "train_method", "RPROP" );
+        cvWriteReal( fs, "dw0", params.rp_dw0 );
+        cvWriteReal( fs, "dw_plus", params.rp_dw_plus );
+        cvWriteReal( fs, "dw_minus", params.rp_dw_minus );
+        cvWriteReal( fs, "dw_min", params.rp_dw_min );
+        cvWriteReal( fs, "dw_max", params.rp_dw_max );
+    }
+
+    cvStartWriteStruct( fs, "term_criteria", CV_NODE_MAP + CV_NODE_FLOW );
+    if( params.term_crit.type & CV_TERMCRIT_EPS )
+        cvWriteReal( fs, "epsilon", params.term_crit.epsilon );
+    if( params.term_crit.type & CV_TERMCRIT_ITER )
+        cvWriteInt( fs, "iterations", params.term_crit.max_iter );
+    cvEndWriteStruct( fs );
+
+    cvEndWriteStruct( fs );
+
+    __END__;
+}
+
+
+void CvANN_MLP::write( CvFileStorage* fs, const char* name ) const
+{
+    CV_FUNCNAME( "CvANN_MLP::write" );
+
+    __BEGIN__;
+
+    int i, l_count = layer_sizes->cols;
+
+    if( !layer_sizes )
+        CV_ERROR( CV_StsError, "The network has not been initialized" );
+
+    cvStartWriteStruct( fs, name, CV_NODE_MAP, CV_TYPE_NAME_ML_ANN_MLP );
+
+    cvWrite( fs, "layer_sizes", layer_sizes );
+
+    write_params( fs );
+
+    cvStartWriteStruct( fs, "input_scale", CV_NODE_SEQ + CV_NODE_FLOW );
+    cvWriteRawData( fs, weights[0], layer_sizes->data.i[0]*2, "d" );
+    cvEndWriteStruct( fs );
+
+    cvStartWriteStruct( fs, "output_scale", CV_NODE_SEQ + CV_NODE_FLOW );
+    cvWriteRawData( fs, weights[l_count], layer_sizes->data.i[l_count-1]*2, "d" );
+    cvEndWriteStruct( fs );
+
+    cvStartWriteStruct( fs, "inv_output_scale", CV_NODE_SEQ + CV_NODE_FLOW );
+    cvWriteRawData( fs, weights[l_count+1], layer_sizes->data.i[l_count-1]*2, "d" );
+    cvEndWriteStruct( fs );
+
+    cvStartWriteStruct( fs, "weights", CV_NODE_SEQ );
+    for( i = 1; i < l_count; i++ )
+    {
+        cvStartWriteStruct( fs, 0, CV_NODE_SEQ + CV_NODE_FLOW );
+        cvWriteRawData( fs, weights[i], (layer_sizes->data.i[i-1]+1)*layer_sizes->data.i[i], "d" );
+        cvEndWriteStruct( fs );
+    }
+
+    cvEndWriteStruct( fs );
+
+    __END__;
+}
+
+
+void CvANN_MLP::read_params( CvFileStorage* fs, CvFileNode* node )
+{
+    //CV_FUNCNAME( "CvANN_MLP::read_params" );
+
+    __BEGIN__;
+
+    const char* activ_func_name = cvReadStringByName( fs, node, "activation_function", 0 );
+    CvFileNode* tparams_node;
+
+    if( activ_func_name )
+        activ_func = strcmp( activ_func_name, "SIGMOID_SYM" ) == 0 ? SIGMOID_SYM :
+                     strcmp( activ_func_name, "IDENTITY" ) == 0 ? IDENTITY :
+                     strcmp( activ_func_name, "GAUSSIAN" ) == 0 ? GAUSSIAN : 0;
+    else
+        activ_func = cvReadIntByName( fs, node, "activation_function" );
+
+    f_param1 = cvReadRealByName( fs, node, "f_param1", 0 );
+    f_param2 = cvReadRealByName( fs, node, "f_param2", 0 );
+
+    set_activ_func( activ_func, f_param1, f_param2 );
+
+    min_val = cvReadRealByName( fs, node, "min_val", 0. );
+    max_val = cvReadRealByName( fs, node, "max_val", 1. );
+    min_val1 = cvReadRealByName( fs, node, "min_val1", 0. );
+    max_val1 = cvReadRealByName( fs, node, "max_val1", 1. );
+
+    tparams_node = cvGetFileNodeByName( fs, node, "training_params" );
+    params = CvANN_MLP_TrainParams();
+
+    if( tparams_node )
+    {
+        const char* tmethod_name = cvReadStringByName( fs, tparams_node, "train_method", "" );
+        CvFileNode* tcrit_node;
+
+        if( strcmp( tmethod_name, "BACKPROP" ) == 0 )
+        {
+            params.train_method = CvANN_MLP_TrainParams::BACKPROP;
+            params.bp_dw_scale = cvReadRealByName( fs, tparams_node, "dw_scale", 0 );
+            params.bp_moment_scale = cvReadRealByName( fs, tparams_node, "moment_scale", 0 );
+        }
+        else if( strcmp( tmethod_name, "RPROP" ) == 0 )
+        {
+            params.train_method = CvANN_MLP_TrainParams::RPROP;
+            params.rp_dw0 = cvReadRealByName( fs, tparams_node, "dw0", 0 );
+            params.rp_dw_plus = cvReadRealByName( fs, tparams_node, "dw_plus", 0 );
+            params.rp_dw_minus = cvReadRealByName( fs, tparams_node, "dw_minus", 0 );
+            params.rp_dw_min = cvReadRealByName( fs, tparams_node, "dw_min", 0 );
+            params.rp_dw_max = cvReadRealByName( fs, tparams_node, "dw_max", 0 );
+        }
+
+        tcrit_node = cvGetFileNodeByName( fs, tparams_node, "term_criteria" );
+        if( tcrit_node )
+        {
+            params.term_crit.epsilon = cvReadRealByName( fs, tcrit_node, "epsilon", -1 );
+            params.term_crit.max_iter = cvReadIntByName( fs, tcrit_node, "iterations", -1 );
+            params.term_crit.type = (params.term_crit.epsilon >= 0 ? CV_TERMCRIT_EPS : 0) +
+                                   (params.term_crit.max_iter >= 0 ? CV_TERMCRIT_ITER : 0);
+        }
+    }
+
+    __END__;
+}
+
+
+void CvANN_MLP::read( CvFileStorage* fs, CvFileNode* node )
+{
+    CvMat* _layer_sizes = 0;
+
+    CV_FUNCNAME( "CvANN_MLP::read" );
+
+    __BEGIN__;
+
+    CvFileNode* w;
+    CvSeqReader reader;
+    int i, l_count;
+
+    _layer_sizes = (CvMat*)cvReadByName( fs, node, "layer_sizes" );
+    CV_CALL( create( _layer_sizes, SIGMOID_SYM, 0, 0 ));
+    l_count = layer_sizes->cols;
+
+    CV_CALL( read_params( fs, node ));
+
+    w = cvGetFileNodeByName( fs, node, "input_scale" );
+    if( !w || CV_NODE_TYPE(w->tag) != CV_NODE_SEQ ||
+        w->data.seq->total != layer_sizes->data.i[0]*2 )
+        CV_ERROR( CV_StsParseError, "input_scale tag is not found or is invalid" );
+
+    CV_CALL( cvReadRawData( fs, w, weights[0], "d" ));
+
+    w = cvGetFileNodeByName( fs, node, "output_scale" );
+    if( !w || CV_NODE_TYPE(w->tag) != CV_NODE_SEQ ||
+        w->data.seq->total != layer_sizes->data.i[l_count-1]*2 )
+        CV_ERROR( CV_StsParseError, "output_scale tag is not found or is invalid" );
+
+    CV_CALL( cvReadRawData( fs, w, weights[l_count], "d" ));
+
+    w = cvGetFileNodeByName( fs, node, "inv_output_scale" );
+    if( !w || CV_NODE_TYPE(w->tag) != CV_NODE_SEQ ||
+        w->data.seq->total != layer_sizes->data.i[l_count-1]*2 )
+        CV_ERROR( CV_StsParseError, "inv_output_scale tag is not found or is invalid" );
+
+    CV_CALL( cvReadRawData( fs, w, weights[l_count+1], "d" ));
+
+    w = cvGetFileNodeByName( fs, node, "weights" );
+    if( !w || CV_NODE_TYPE(w->tag) != CV_NODE_SEQ ||
+        w->data.seq->total != l_count - 1 )
+        CV_ERROR( CV_StsParseError, "weights tag is not found or is invalid" );
+
+    cvStartReadSeq( w->data.seq, &reader );
+
+    for( i = 1; i < l_count; i++ )
+    {
+        w = (CvFileNode*)reader.ptr;
+        CV_CALL( cvReadRawData( fs, w, weights[i], "d" ));
+        CV_NEXT_SEQ_ELEM( reader.seq->elem_size, reader );
+    }
+
+    __END__;
+}
+
+using namespace cv;
+
+void CvANN_MLP::create( const Mat& _layer_sizes, int _activ_func,
+                       double _f_param1, double _f_param2 )
+{
+    CvMat layer_sizes = _layer_sizes;
+    create( &layer_sizes, _activ_func, _f_param1, _f_param2 );
+}
+
+int CvANN_MLP::train( const Mat& _inputs, const Mat& _outputs,
+                     const Mat& _sample_weights, const Mat& _sample_idx,
+                     CvANN_MLP_TrainParams _params, int flags )
+{
+    CvMat inputs = _inputs, outputs = _outputs, sweights = _sample_weights, sidx = _sample_idx;
+    return train(&inputs, &outputs, sweights.data.ptr ? &sweights : 0,
+                 sidx.data.ptr ? &sidx : 0, _params, flags); 
+}
+
+float CvANN_MLP::predict( const Mat& _inputs, Mat& _outputs ) const
+{
+    CV_Assert(layer_sizes != 0);
+    _outputs.create(_inputs.rows, layer_sizes->data.i[layer_sizes->cols-1], _inputs.type());
+    CvMat inputs = _inputs, outputs = _outputs;
+    
+    return predict(&inputs, &outputs); 
+}
+
+/* End of file. */