+++ /dev/null
-/*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"
-
-/****************************************************************************************\
- COPYRIGHT NOTICE
- ----------------
-
- The code has been derived from libsvm library (version 2.6)
- (http://www.csie.ntu.edu.tw/~cjlin/libsvm).
-
- Here is the orignal copyright:
-------------------------------------------------------------------------------------------
- Copyright (c) 2000-2003 Chih-Chung Chang and Chih-Jen Lin
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions
- are met:
-
- 1. Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
-
- 2. 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.
-
- 3. Neither name of copyright holders nor the names of its contributors
- may 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 REGENTS 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.
-\****************************************************************************************/
-
-#define CV_SVM_MIN_CACHE_SIZE (40 << 20) /* 40Mb */
-
-#include <stdarg.h>
-#include <ctype.h>
-
-#if _MSC_VER >= 1200
-#pragma warning( disable: 4514 ) /* unreferenced inline functions */
-#endif
-
-#if 1
-typedef float Qfloat;
-#define QFLOAT_TYPE CV_32F
-#else
-typedef double Qfloat;
-#define QFLOAT_TYPE CV_64F
-#endif
-
-// Param Grid
-bool CvParamGrid::check() const
-{
- bool ok = false;
-
- CV_FUNCNAME( "CvParamGrid::check" );
- __BEGIN__;
-
- if( min_val > max_val )
- CV_ERROR( CV_StsBadArg, "Lower bound of the grid must be less then the upper one" );
- if( min_val < DBL_EPSILON )
- CV_ERROR( CV_StsBadArg, "Lower bound of the grid must be positive" );
- if( step < 1. + FLT_EPSILON )
- CV_ERROR( CV_StsBadArg, "Grid step must greater then 1" );
-
- ok = true;
-
- __END__;
-
- return ok;
-}
-
-CvParamGrid CvSVM::get_default_grid( int param_id )
-{
- CvParamGrid grid;
- if( param_id == CvSVM::C )
- {
- grid.min_val = 0.1;
- grid.max_val = 500;
- grid.step = 5; // total iterations = 5
- }
- else if( param_id == CvSVM::GAMMA )
- {
- grid.min_val = 1e-5;
- grid.max_val = 0.6;
- grid.step = 15; // total iterations = 4
- }
- else if( param_id == CvSVM::P )
- {
- grid.min_val = 0.01;
- grid.max_val = 100;
- grid.step = 7; // total iterations = 4
- }
- else if( param_id == CvSVM::NU )
- {
- grid.min_val = 0.01;
- grid.max_val = 0.2;
- grid.step = 3; // total iterations = 3
- }
- else if( param_id == CvSVM::COEF )
- {
- grid.min_val = 0.1;
- grid.max_val = 300;
- grid.step = 14; // total iterations = 3
- }
- else if( param_id == CvSVM::DEGREE )
- {
- grid.min_val = 0.01;
- grid.max_val = 4;
- grid.step = 7; // total iterations = 3
- }
- else
- cvError( CV_StsBadArg, "CvSVM::get_default_grid", "Invalid type of parameter "
- "(use one of CvSVM::C, CvSVM::GAMMA et al.)", __FILE__, __LINE__ );
- return grid;
-}
-
-// SVM training parameters
-CvSVMParams::CvSVMParams() :
- svm_type(CvSVM::C_SVC), kernel_type(CvSVM::RBF), degree(0),
- gamma(1), coef0(0), C(1), nu(0), p(0), class_weights(0)
-{
- term_crit = cvTermCriteria( CV_TERMCRIT_ITER+CV_TERMCRIT_EPS, 1000, FLT_EPSILON );
-}
-
-
-CvSVMParams::CvSVMParams( int _svm_type, int _kernel_type,
- double _degree, double _gamma, double _coef0,
- double _Con, double _nu, double _p,
- CvMat* _class_weights, CvTermCriteria _term_crit ) :
- svm_type(_svm_type), kernel_type(_kernel_type),
- degree(_degree), gamma(_gamma), coef0(_coef0),
- C(_Con), nu(_nu), p(_p), class_weights(_class_weights), term_crit(_term_crit)
-{
-}
-
-
-/////////////////////////////////////// SVM kernel ///////////////////////////////////////
-
-CvSVMKernel::CvSVMKernel()
-{
- clear();
-}
-
-
-void CvSVMKernel::clear()
-{
- params = 0;
- calc_func = 0;
-}
-
-
-CvSVMKernel::~CvSVMKernel()
-{
-}
-
-
-CvSVMKernel::CvSVMKernel( const CvSVMParams* _params, Calc _calc_func )
-{
- clear();
- create( _params, _calc_func );
-}
-
-
-bool CvSVMKernel::create( const CvSVMParams* _params, Calc _calc_func )
-{
- clear();
- params = _params;
- calc_func = _calc_func;
-
- if( !calc_func )
- calc_func = params->kernel_type == CvSVM::RBF ? &CvSVMKernel::calc_rbf :
- params->kernel_type == CvSVM::POLY ? &CvSVMKernel::calc_poly :
- params->kernel_type == CvSVM::SIGMOID ? &CvSVMKernel::calc_sigmoid :
- &CvSVMKernel::calc_linear;
-
- return true;
-}
-
-
-void CvSVMKernel::calc_non_rbf_base( int vcount, int var_count, const float** vecs,
- const float* another, Qfloat* results,
- double alpha, double beta )
-{
- int j, k;
- for( j = 0; j < vcount; j++ )
- {
- const float* sample = vecs[j];
- double s = 0;
- for( k = 0; k <= var_count - 4; k += 4 )
- s += sample[k]*another[k] + sample[k+1]*another[k+1] +
- sample[k+2]*another[k+2] + sample[k+3]*another[k+3];
- for( ; k < var_count; k++ )
- s += sample[k]*another[k];
- results[j] = (Qfloat)(s*alpha + beta);
- }
-}
-
-
-void CvSVMKernel::calc_linear( int vcount, int var_count, const float** vecs,
- const float* another, Qfloat* results )
-{
- calc_non_rbf_base( vcount, var_count, vecs, another, results, 1, 0 );
-}
-
-
-void CvSVMKernel::calc_poly( int vcount, int var_count, const float** vecs,
- const float* another, Qfloat* results )
-{
- CvMat R = cvMat( 1, vcount, QFLOAT_TYPE, results );
- calc_non_rbf_base( vcount, var_count, vecs, another, results, params->gamma, params->coef0 );
- cvPow( &R, &R, params->degree );
-}
-
-
-void CvSVMKernel::calc_sigmoid( int vcount, int var_count, const float** vecs,
- const float* another, Qfloat* results )
-{
- int j;
- calc_non_rbf_base( vcount, var_count, vecs, another, results,
- -2*params->gamma, -2*params->coef0 );
- // TODO: speedup this
- for( j = 0; j < vcount; j++ )
- {
- Qfloat t = results[j];
- double e = exp(-fabs(t));
- if( t > 0 )
- results[j] = (Qfloat)((1. - e)/(1. + e));
- else
- results[j] = (Qfloat)((e - 1.)/(e + 1.));
- }
-}
-
-
-void CvSVMKernel::calc_rbf( int vcount, int var_count, const float** vecs,
- const float* another, Qfloat* results )
-{
- CvMat R = cvMat( 1, vcount, QFLOAT_TYPE, results );
- double gamma = -params->gamma;
- int j, k;
-
- for( j = 0; j < vcount; j++ )
- {
- const float* sample = vecs[j];
- double s = 0;
-
- for( k = 0; k <= var_count - 4; k += 4 )
- {
- double t0 = sample[k] - another[k];
- double t1 = sample[k+1] - another[k+1];
-
- s += t0*t0 + t1*t1;
-
- t0 = sample[k+2] - another[k+2];
- t1 = sample[k+3] - another[k+3];
-
- s += t0*t0 + t1*t1;
- }
-
- for( ; k < var_count; k++ )
- {
- double t0 = sample[k] - another[k];
- s += t0*t0;
- }
- results[j] = (Qfloat)(s*gamma);
- }
-
- cvExp( &R, &R );
-}
-
-
-void CvSVMKernel::calc( int vcount, int var_count, const float** vecs,
- const float* another, Qfloat* results )
-{
- const Qfloat max_val = (Qfloat)(FLT_MAX*1e-3);
- int j;
- (this->*calc_func)( vcount, var_count, vecs, another, results );
- for( j = 0; j < vcount; j++ )
- {
- if( results[j] > max_val )
- results[j] = max_val;
- }
-}
-
-
-// Generalized SMO+SVMlight algorithm
-// Solves:
-//
-// min [0.5(\alpha^T Q \alpha) + b^T \alpha]
-//
-// y^T \alpha = \delta
-// y_i = +1 or -1
-// 0 <= alpha_i <= Cp for y_i = 1
-// 0 <= alpha_i <= Cn for y_i = -1
-//
-// Given:
-//
-// Q, b, y, Cp, Cn, and an initial feasible point \alpha
-// l is the size of vectors and matrices
-// eps is the stopping criterion
-//
-// solution will be put in \alpha, objective value will be put in obj
-//
-
-void CvSVMSolver::clear()
-{
- G = 0;
- alpha = 0;
- y = 0;
- b = 0;
- buf[0] = buf[1] = 0;
- cvReleaseMemStorage( &storage );
- kernel = 0;
- select_working_set_func = 0;
- calc_rho_func = 0;
-
- rows = 0;
- samples = 0;
- get_row_func = 0;
-}
-
-
-CvSVMSolver::CvSVMSolver()
-{
- storage = 0;
- clear();
-}
-
-
-CvSVMSolver::~CvSVMSolver()
-{
- clear();
-}
-
-
-CvSVMSolver::CvSVMSolver( int _sample_count, int _var_count, const float** _samples, schar* _y,
- int _alpha_count, double* _alpha, double _Cp, double _Cn,
- CvMemStorage* _storage, CvSVMKernel* _kernel, GetRow _get_row,
- SelectWorkingSet _select_working_set, CalcRho _calc_rho )
-{
- storage = 0;
- create( _sample_count, _var_count, _samples, _y, _alpha_count, _alpha, _Cp, _Cn,
- _storage, _kernel, _get_row, _select_working_set, _calc_rho );
-}
-
-
-bool CvSVMSolver::create( int _sample_count, int _var_count, const float** _samples, schar* _y,
- int _alpha_count, double* _alpha, double _Cp, double _Cn,
- CvMemStorage* _storage, CvSVMKernel* _kernel, GetRow _get_row,
- SelectWorkingSet _select_working_set, CalcRho _calc_rho )
-{
- bool ok = false;
- int i, svm_type;
-
- CV_FUNCNAME( "CvSVMSolver::create" );
-
- __BEGIN__;
-
- int rows_hdr_size;
-
- clear();
-
- sample_count = _sample_count;
- var_count = _var_count;
- samples = _samples;
- y = _y;
- alpha_count = _alpha_count;
- alpha = _alpha;
- kernel = _kernel;
-
- C[0] = _Cn;
- C[1] = _Cp;
- eps = kernel->params->term_crit.epsilon;
- max_iter = kernel->params->term_crit.max_iter;
- storage = cvCreateChildMemStorage( _storage );
-
- b = (double*)cvMemStorageAlloc( storage, alpha_count*sizeof(b[0]));
- alpha_status = (schar*)cvMemStorageAlloc( storage, alpha_count*sizeof(alpha_status[0]));
- G = (double*)cvMemStorageAlloc( storage, alpha_count*sizeof(G[0]));
- for( i = 0; i < 2; i++ )
- buf[i] = (Qfloat*)cvMemStorageAlloc( storage, sample_count*2*sizeof(buf[i][0]) );
- svm_type = kernel->params->svm_type;
-
- select_working_set_func = _select_working_set;
- if( !select_working_set_func )
- select_working_set_func = svm_type == CvSVM::NU_SVC || svm_type == CvSVM::NU_SVR ?
- &CvSVMSolver::select_working_set_nu_svm : &CvSVMSolver::select_working_set;
-
- calc_rho_func = _calc_rho;
- if( !calc_rho_func )
- calc_rho_func = svm_type == CvSVM::NU_SVC || svm_type == CvSVM::NU_SVR ?
- &CvSVMSolver::calc_rho_nu_svm : &CvSVMSolver::calc_rho;
-
- get_row_func = _get_row;
- if( !get_row_func )
- get_row_func = params->svm_type == CvSVM::EPS_SVR ||
- params->svm_type == CvSVM::NU_SVR ? &CvSVMSolver::get_row_svr :
- params->svm_type == CvSVM::C_SVC ||
- params->svm_type == CvSVM::NU_SVC ? &CvSVMSolver::get_row_svc :
- &CvSVMSolver::get_row_one_class;
-
- cache_line_size = sample_count*sizeof(Qfloat);
- // cache size = max(num_of_samples^2*sizeof(Qfloat)*0.25, 64Kb)
- // (assuming that for large training sets ~25% of Q matrix is used)
- cache_size = MAX( cache_line_size*sample_count/4, CV_SVM_MIN_CACHE_SIZE );
-
- // the size of Q matrix row headers
- rows_hdr_size = sample_count*sizeof(rows[0]);
- if( rows_hdr_size > storage->block_size )
- CV_ERROR( CV_StsOutOfRange, "Too small storage block size" );
-
- lru_list.prev = lru_list.next = &lru_list;
- rows = (CvSVMKernelRow*)cvMemStorageAlloc( storage, rows_hdr_size );
- memset( rows, 0, rows_hdr_size );
-
- ok = true;
-
- __END__;
-
- return ok;
-}
-
-
-float* CvSVMSolver::get_row_base( int i, bool* _existed )
-{
- int i1 = i < sample_count ? i : i - sample_count;
- CvSVMKernelRow* row = rows + i1;
- bool existed = row->data != 0;
- Qfloat* data;
-
- if( existed || cache_size <= 0 )
- {
- CvSVMKernelRow* del_row = existed ? row : lru_list.prev;
- data = del_row->data;
- assert( data != 0 );
-
- // delete row from the LRU list
- del_row->data = 0;
- del_row->prev->next = del_row->next;
- del_row->next->prev = del_row->prev;
- }
- else
- {
- data = (Qfloat*)cvMemStorageAlloc( storage, cache_line_size );
- cache_size -= cache_line_size;
- }
-
- // insert row into the LRU list
- row->data = data;
- row->prev = &lru_list;
- row->next = lru_list.next;
- row->prev->next = row->next->prev = row;
-
- if( !existed )
- {
- kernel->calc( sample_count, var_count, samples, samples[i1], row->data );
- }
-
- if( _existed )
- *_existed = existed;
-
- return row->data;
-}
-
-
-float* CvSVMSolver::get_row_svc( int i, float* row, float*, bool existed )
-{
- if( !existed )
- {
- const schar* _y = y;
- int j, len = sample_count;
- assert( _y && i < sample_count );
-
- if( _y[i] > 0 )
- {
- for( j = 0; j < len; j++ )
- row[j] = _y[j]*row[j];
- }
- else
- {
- for( j = 0; j < len; j++ )
- row[j] = -_y[j]*row[j];
- }
- }
- return row;
-}
-
-
-float* CvSVMSolver::get_row_one_class( int, float* row, float*, bool )
-{
- return row;
-}
-
-
-float* CvSVMSolver::get_row_svr( int i, float* row, float* dst, bool )
-{
- int j, len = sample_count;
- Qfloat* dst_pos = dst;
- Qfloat* dst_neg = dst + len;
- if( i >= len )
- {
- Qfloat* temp;
- CV_SWAP( dst_pos, dst_neg, temp );
- }
-
- for( j = 0; j < len; j++ )
- {
- Qfloat t = row[j];
- dst_pos[j] = t;
- dst_neg[j] = -t;
- }
- return dst;
-}
-
-
-
-float* CvSVMSolver::get_row( int i, float* dst )
-{
- bool existed = false;
- float* row = get_row_base( i, &existed );
- return (this->*get_row_func)( i, row, dst, existed );
-}
-
-
-#undef is_upper_bound
-#define is_upper_bound(i) (alpha_status[i] > 0)
-
-#undef is_lower_bound
-#define is_lower_bound(i) (alpha_status[i] < 0)
-
-#undef is_free
-#define is_free(i) (alpha_status[i] == 0)
-
-#undef get_C
-#define get_C(i) (C[y[i]>0])
-
-#undef update_alpha_status
-#define update_alpha_status(i) \
- alpha_status[i] = (schar)(alpha[i] >= get_C(i) ? 1 : alpha[i] <= 0 ? -1 : 0)
-
-#undef reconstruct_gradient
-#define reconstruct_gradient() /* empty for now */
-
-
-bool CvSVMSolver::solve_generic( CvSVMSolutionInfo& si )
-{
- int iter = 0;
- int i, j, k;
-
- // 1. initialize gradient and alpha status
- for( i = 0; i < alpha_count; i++ )
- {
- update_alpha_status(i);
- G[i] = b[i];
- if( fabs(G[i]) > 1e200 )
- return false;
- }
-
- for( i = 0; i < alpha_count; i++ )
- {
- if( !is_lower_bound(i) )
- {
- const Qfloat *Q_i = get_row( i, buf[0] );
- double alpha_i = alpha[i];
-
- for( j = 0; j < alpha_count; j++ )
- G[j] += alpha_i*Q_i[j];
- }
- }
-
- // 2. optimization loop
- for(;;)
- {
- const Qfloat *Q_i, *Q_j;
- double C_i, C_j;
- double old_alpha_i, old_alpha_j, alpha_i, alpha_j;
- double delta_alpha_i, delta_alpha_j;
-
-#ifdef _DEBUG
- for( i = 0; i < alpha_count; i++ )
- {
- if( fabs(G[i]) > 1e+300 )
- return false;
-
- if( fabs(alpha[i]) > 1e16 )
- return false;
- }
-#endif
-
- if( (this->*select_working_set_func)( i, j ) != 0 || iter++ >= max_iter )
- break;
-
- Q_i = get_row( i, buf[0] );
- Q_j = get_row( j, buf[1] );
-
- C_i = get_C(i);
- C_j = get_C(j);
-
- alpha_i = old_alpha_i = alpha[i];
- alpha_j = old_alpha_j = alpha[j];
-
- if( y[i] != y[j] )
- {
- double denom = Q_i[i]+Q_j[j]+2*Q_i[j];
- double delta = (-G[i]-G[j])/MAX(fabs(denom),FLT_EPSILON);
- double diff = alpha_i - alpha_j;
- alpha_i += delta;
- alpha_j += delta;
-
- if( diff > 0 && alpha_j < 0 )
- {
- alpha_j = 0;
- alpha_i = diff;
- }
- else if( diff <= 0 && alpha_i < 0 )
- {
- alpha_i = 0;
- alpha_j = -diff;
- }
-
- if( diff > C_i - C_j && alpha_i > C_i )
- {
- alpha_i = C_i;
- alpha_j = C_i - diff;
- }
- else if( diff <= C_i - C_j && alpha_j > C_j )
- {
- alpha_j = C_j;
- alpha_i = C_j + diff;
- }
- }
- else
- {
- double denom = Q_i[i]+Q_j[j]-2*Q_i[j];
- double delta = (G[i]-G[j])/MAX(fabs(denom),FLT_EPSILON);
- double sum = alpha_i + alpha_j;
- alpha_i -= delta;
- alpha_j += delta;
-
- if( sum > C_i && alpha_i > C_i )
- {
- alpha_i = C_i;
- alpha_j = sum - C_i;
- }
- else if( sum <= C_i && alpha_j < 0)
- {
- alpha_j = 0;
- alpha_i = sum;
- }
-
- if( sum > C_j && alpha_j > C_j )
- {
- alpha_j = C_j;
- alpha_i = sum - C_j;
- }
- else if( sum <= C_j && alpha_i < 0 )
- {
- alpha_i = 0;
- alpha_j = sum;
- }
- }
-
- // update alpha
- alpha[i] = alpha_i;
- alpha[j] = alpha_j;
- update_alpha_status(i);
- update_alpha_status(j);
-
- // update G
- delta_alpha_i = alpha_i - old_alpha_i;
- delta_alpha_j = alpha_j - old_alpha_j;
-
- for( k = 0; k < alpha_count; k++ )
- G[k] += Q_i[k]*delta_alpha_i + Q_j[k]*delta_alpha_j;
- }
-
- // calculate rho
- (this->*calc_rho_func)( si.rho, si.r );
-
- // calculate objective value
- for( i = 0, si.obj = 0; i < alpha_count; i++ )
- si.obj += alpha[i] * (G[i] + b[i]);
-
- si.obj *= 0.5;
-
- si.upper_bound_p = C[1];
- si.upper_bound_n = C[0];
-
- return true;
-}
-
-
-// return 1 if already optimal, return 0 otherwise
-bool
-CvSVMSolver::select_working_set( int& out_i, int& out_j )
-{
- // return i,j which maximize -grad(f)^T d , under constraint
- // if alpha_i == C, d != +1
- // if alpha_i == 0, d != -1
- double Gmax1 = -DBL_MAX; // max { -grad(f)_i * d | y_i*d = +1 }
- int Gmax1_idx = -1;
-
- double Gmax2 = -DBL_MAX; // max { -grad(f)_i * d | y_i*d = -1 }
- int Gmax2_idx = -1;
-
- int i;
-
- for( i = 0; i < alpha_count; i++ )
- {
- double t;
-
- if( y[i] > 0 ) // y = +1
- {
- if( !is_upper_bound(i) && (t = -G[i]) > Gmax1 ) // d = +1
- {
- Gmax1 = t;
- Gmax1_idx = i;
- }
- if( !is_lower_bound(i) && (t = G[i]) > Gmax2 ) // d = -1
- {
- Gmax2 = t;
- Gmax2_idx = i;
- }
- }
- else // y = -1
- {
- if( !is_upper_bound(i) && (t = -G[i]) > Gmax2 ) // d = +1
- {
- Gmax2 = t;
- Gmax2_idx = i;
- }
- if( !is_lower_bound(i) && (t = G[i]) > Gmax1 ) // d = -1
- {
- Gmax1 = t;
- Gmax1_idx = i;
- }
- }
- }
-
- out_i = Gmax1_idx;
- out_j = Gmax2_idx;
-
- return Gmax1 + Gmax2 < eps;
-}
-
-
-void
-CvSVMSolver::calc_rho( double& rho, double& r )
-{
- int i, nr_free = 0;
- double ub = DBL_MAX, lb = -DBL_MAX, sum_free = 0;
-
- for( i = 0; i < alpha_count; i++ )
- {
- double yG = y[i]*G[i];
-
- if( is_lower_bound(i) )
- {
- if( y[i] > 0 )
- ub = MIN(ub,yG);
- else
- lb = MAX(lb,yG);
- }
- else if( is_upper_bound(i) )
- {
- if( y[i] < 0)
- ub = MIN(ub,yG);
- else
- lb = MAX(lb,yG);
- }
- else
- {
- ++nr_free;
- sum_free += yG;
- }
- }
-
- rho = nr_free > 0 ? sum_free/nr_free : (ub + lb)*0.5;
- r = 0;
-}
-
-
-bool
-CvSVMSolver::select_working_set_nu_svm( int& out_i, int& out_j )
-{
- // return i,j which maximize -grad(f)^T d , under constraint
- // if alpha_i == C, d != +1
- // if alpha_i == 0, d != -1
- double Gmax1 = -DBL_MAX; // max { -grad(f)_i * d | y_i = +1, d = +1 }
- int Gmax1_idx = -1;
-
- double Gmax2 = -DBL_MAX; // max { -grad(f)_i * d | y_i = +1, d = -1 }
- int Gmax2_idx = -1;
-
- double Gmax3 = -DBL_MAX; // max { -grad(f)_i * d | y_i = -1, d = +1 }
- int Gmax3_idx = -1;
-
- double Gmax4 = -DBL_MAX; // max { -grad(f)_i * d | y_i = -1, d = -1 }
- int Gmax4_idx = -1;
-
- int i;
-
- for( i = 0; i < alpha_count; i++ )
- {
- double t;
-
- if( y[i] > 0 ) // y == +1
- {
- if( !is_upper_bound(i) && (t = -G[i]) > Gmax1 ) // d = +1
- {
- Gmax1 = t;
- Gmax1_idx = i;
- }
- if( !is_lower_bound(i) && (t = G[i]) > Gmax2 ) // d = -1
- {
- Gmax2 = t;
- Gmax2_idx = i;
- }
- }
- else // y == -1
- {
- if( !is_upper_bound(i) && (t = -G[i]) > Gmax3 ) // d = +1
- {
- Gmax3 = t;
- Gmax3_idx = i;
- }
- if( !is_lower_bound(i) && (t = G[i]) > Gmax4 ) // d = -1
- {
- Gmax4 = t;
- Gmax4_idx = i;
- }
- }
- }
-
- if( MAX(Gmax1 + Gmax2, Gmax3 + Gmax4) < eps )
- return 1;
-
- if( Gmax1 + Gmax2 > Gmax3 + Gmax4 )
- {
- out_i = Gmax1_idx;
- out_j = Gmax2_idx;
- }
- else
- {
- out_i = Gmax3_idx;
- out_j = Gmax4_idx;
- }
- return 0;
-}
-
-
-void
-CvSVMSolver::calc_rho_nu_svm( double& rho, double& r )
-{
- int nr_free1 = 0, nr_free2 = 0;
- double ub1 = DBL_MAX, ub2 = DBL_MAX;
- double lb1 = -DBL_MAX, lb2 = -DBL_MAX;
- double sum_free1 = 0, sum_free2 = 0;
- double r1, r2;
-
- int i;
-
- for( i = 0; i < alpha_count; i++ )
- {
- double G_i = G[i];
- if( y[i] > 0 )
- {
- if( is_lower_bound(i) )
- ub1 = MIN( ub1, G_i );
- else if( is_upper_bound(i) )
- lb1 = MAX( lb1, G_i );
- else
- {
- ++nr_free1;
- sum_free1 += G_i;
- }
- }
- else
- {
- if( is_lower_bound(i) )
- ub2 = MIN( ub2, G_i );
- else if( is_upper_bound(i) )
- lb2 = MAX( lb2, G_i );
- else
- {
- ++nr_free2;
- sum_free2 += G_i;
- }
- }
- }
-
- r1 = nr_free1 > 0 ? sum_free1/nr_free1 : (ub1 + lb1)*0.5;
- r2 = nr_free2 > 0 ? sum_free2/nr_free2 : (ub2 + lb2)*0.5;
-
- rho = (r1 - r2)*0.5;
- r = (r1 + r2)*0.5;
-}
-
-
-/*
-///////////////////////// construct and solve various formulations ///////////////////////
-*/
-
-bool CvSVMSolver::solve_c_svc( int _sample_count, int _var_count, const float** _samples, schar* _y,
- double _Cp, double _Cn, CvMemStorage* _storage,
- CvSVMKernel* _kernel, double* _alpha, CvSVMSolutionInfo& _si )
-{
- int i;
-
- if( !create( _sample_count, _var_count, _samples, _y, _sample_count,
- _alpha, _Cp, _Cn, _storage, _kernel, &CvSVMSolver::get_row_svc,
- &CvSVMSolver::select_working_set, &CvSVMSolver::calc_rho ))
- return false;
-
- for( i = 0; i < sample_count; i++ )
- {
- alpha[i] = 0;
- b[i] = -1;
- }
-
- if( !solve_generic( _si ))
- return false;
-
- for( i = 0; i < sample_count; i++ )
- alpha[i] *= y[i];
-
- return true;
-}
-
-
-bool CvSVMSolver::solve_nu_svc( int _sample_count, int _var_count, const float** _samples, schar* _y,
- CvMemStorage* _storage, CvSVMKernel* _kernel,
- double* _alpha, CvSVMSolutionInfo& _si )
-{
- int i;
- double sum_pos, sum_neg, inv_r;
-
- if( !create( _sample_count, _var_count, _samples, _y, _sample_count,
- _alpha, 1., 1., _storage, _kernel, &CvSVMSolver::get_row_svc,
- &CvSVMSolver::select_working_set_nu_svm, &CvSVMSolver::calc_rho_nu_svm ))
- return false;
-
- sum_pos = kernel->params->nu * sample_count * 0.5;
- sum_neg = kernel->params->nu * sample_count * 0.5;
-
- for( i = 0; i < sample_count; i++ )
- {
- if( y[i] > 0 )
- {
- alpha[i] = MIN(1.0, sum_pos);
- sum_pos -= alpha[i];
- }
- else
- {
- alpha[i] = MIN(1.0, sum_neg);
- sum_neg -= alpha[i];
- }
- b[i] = 0;
- }
-
- if( !solve_generic( _si ))
- return false;
-
- inv_r = 1./_si.r;
-
- for( i = 0; i < sample_count; i++ )
- alpha[i] *= y[i]*inv_r;
-
- _si.rho *= inv_r;
- _si.obj *= (inv_r*inv_r);
- _si.upper_bound_p = inv_r;
- _si.upper_bound_n = inv_r;
-
- return true;
-}
-
-
-bool CvSVMSolver::solve_one_class( int _sample_count, int _var_count, const float** _samples,
- CvMemStorage* _storage, CvSVMKernel* _kernel,
- double* _alpha, CvSVMSolutionInfo& _si )
-{
- int i, n;
- double nu = _kernel->params->nu;
-
- if( !create( _sample_count, _var_count, _samples, 0, _sample_count,
- _alpha, 1., 1., _storage, _kernel, &CvSVMSolver::get_row_one_class,
- &CvSVMSolver::select_working_set, &CvSVMSolver::calc_rho ))
- return false;
-
- y = (schar*)cvMemStorageAlloc( storage, sample_count*sizeof(y[0]) );
- n = cvRound( nu*sample_count );
-
- for( i = 0; i < sample_count; i++ )
- {
- y[i] = 1;
- b[i] = 0;
- alpha[i] = i < n ? 1 : 0;
- }
-
- if( n < sample_count )
- alpha[n] = nu * sample_count - n;
- else
- alpha[n-1] = nu * sample_count - (n-1);
-
- return solve_generic(_si);
-}
-
-
-bool CvSVMSolver::solve_eps_svr( int _sample_count, int _var_count, const float** _samples,
- const float* _y, CvMemStorage* _storage,
- CvSVMKernel* _kernel, double* _alpha, CvSVMSolutionInfo& _si )
-{
- int i;
- double p = _kernel->params->p, C = _kernel->params->C;
-
- if( !create( _sample_count, _var_count, _samples, 0,
- _sample_count*2, 0, C, C, _storage, _kernel, &CvSVMSolver::get_row_svr,
- &CvSVMSolver::select_working_set, &CvSVMSolver::calc_rho ))
- return false;
-
- y = (schar*)cvMemStorageAlloc( storage, sample_count*2*sizeof(y[0]) );
- alpha = (double*)cvMemStorageAlloc( storage, alpha_count*sizeof(alpha[0]) );
-
- for( i = 0; i < sample_count; i++ )
- {
- alpha[i] = 0;
- b[i] = p - _y[i];
- y[i] = 1;
-
- alpha[i+sample_count] = 0;
- b[i+sample_count] = p + _y[i];
- y[i+sample_count] = -1;
- }
-
- if( !solve_generic( _si ))
- return false;
-
- for( i = 0; i < sample_count; i++ )
- _alpha[i] = alpha[i] - alpha[i+sample_count];
-
- return true;
-}
-
-
-bool CvSVMSolver::solve_nu_svr( int _sample_count, int _var_count, const float** _samples,
- const float* _y, CvMemStorage* _storage,
- CvSVMKernel* _kernel, double* _alpha, CvSVMSolutionInfo& _si )
-{
- int i;
- double C = _kernel->params->C, sum;
-
- if( !create( _sample_count, _var_count, _samples, 0,
- _sample_count*2, 0, 1., 1., _storage, _kernel, &CvSVMSolver::get_row_svr,
- &CvSVMSolver::select_working_set_nu_svm, &CvSVMSolver::calc_rho_nu_svm ))
- return false;
-
- y = (schar*)cvMemStorageAlloc( storage, sample_count*2*sizeof(y[0]) );
- alpha = (double*)cvMemStorageAlloc( storage, alpha_count*sizeof(alpha[0]) );
- sum = C * _kernel->params->nu * sample_count * 0.5;
-
- for( i = 0; i < sample_count; i++ )
- {
- alpha[i] = alpha[i + sample_count] = MIN(sum, C);
- sum -= alpha[i];
-
- b[i] = -_y[i];
- y[i] = 1;
-
- b[i + sample_count] = _y[i];
- y[i + sample_count] = -1;
- }
-
- if( !solve_generic( _si ))
- return false;
-
- for( i = 0; i < sample_count; i++ )
- _alpha[i] = alpha[i] - alpha[i+sample_count];
-
- return true;
-}
-
-
-//////////////////////////////////////////////////////////////////////////////////////////
-
-CvSVM::CvSVM()
-{
- decision_func = 0;
- class_labels = 0;
- class_weights = 0;
- storage = 0;
- var_idx = 0;
- kernel = 0;
- solver = 0;
- default_model_name = "my_svm";
-
- clear();
-}
-
-
-CvSVM::~CvSVM()
-{
- clear();
-}
-
-
-void CvSVM::clear()
-{
- cvFree( &decision_func );
- cvReleaseMat( &class_labels );
- cvReleaseMat( &class_weights );
- cvReleaseMemStorage( &storage );
- cvReleaseMat( &var_idx );
- delete kernel;
- delete solver;
- kernel = 0;
- solver = 0;
- var_all = 0;
- sv = 0;
- sv_total = 0;
-}
-
-
-CvSVM::CvSVM( const CvMat* _train_data, const CvMat* _responses,
- const CvMat* _var_idx, const CvMat* _sample_idx, CvSVMParams _params )
-{
- decision_func = 0;
- class_labels = 0;
- class_weights = 0;
- storage = 0;
- var_idx = 0;
- kernel = 0;
- solver = 0;
- default_model_name = "my_svm";
-
- train( _train_data, _responses, _var_idx, _sample_idx, _params );
-}
-
-
-int CvSVM::get_support_vector_count() const
-{
- return sv_total;
-}
-
-
-const float* CvSVM::get_support_vector(int i) const
-{
- return sv && (unsigned)i < (unsigned)sv_total ? sv[i] : 0;
-}
-
-
-bool CvSVM::set_params( const CvSVMParams& _params )
-{
- bool ok = false;
-
- CV_FUNCNAME( "CvSVM::set_params" );
-
- __BEGIN__;
-
- int kernel_type, svm_type;
-
- params = _params;
-
- kernel_type = params.kernel_type;
- svm_type = params.svm_type;
-
- if( kernel_type != LINEAR && kernel_type != POLY &&
- kernel_type != SIGMOID && kernel_type != RBF )
- CV_ERROR( CV_StsBadArg, "Unknown/unsupported kernel type" );
-
- if( kernel_type == LINEAR )
- params.gamma = 1;
- else if( params.gamma <= 0 )
- CV_ERROR( CV_StsOutOfRange, "gamma parameter of the kernel must be positive" );
-
- if( kernel_type != SIGMOID && kernel_type != POLY )
- params.coef0 = 0;
- else if( params.coef0 < 0 )
- CV_ERROR( CV_StsOutOfRange, "The kernel parameter <coef0> must be positive or zero" );
-
- if( kernel_type != POLY )
- params.degree = 0;
- else if( params.degree <= 0 )
- CV_ERROR( CV_StsOutOfRange, "The kernel parameter <degree> must be positive" );
-
- if( svm_type != C_SVC && svm_type != NU_SVC &&
- svm_type != ONE_CLASS && svm_type != EPS_SVR &&
- svm_type != NU_SVR )
- CV_ERROR( CV_StsBadArg, "Unknown/unsupported SVM type" );
-
- if( svm_type == ONE_CLASS || svm_type == NU_SVC )
- params.C = 0;
- else if( params.C <= 0 )
- CV_ERROR( CV_StsOutOfRange, "The parameter C must be positive" );
-
- if( svm_type == C_SVC || svm_type == EPS_SVR )
- params.nu = 0;
- else if( params.nu <= 0 || params.nu >= 1 )
- CV_ERROR( CV_StsOutOfRange, "The parameter nu must be between 0 and 1" );
-
- if( svm_type != EPS_SVR )
- params.p = 0;
- else if( params.p <= 0 )
- CV_ERROR( CV_StsOutOfRange, "The parameter p must be positive" );
-
- if( svm_type != C_SVC )
- params.class_weights = 0;
-
- params.term_crit = cvCheckTermCriteria( params.term_crit, DBL_EPSILON, INT_MAX );
- params.term_crit.epsilon = MAX( params.term_crit.epsilon, DBL_EPSILON );
- ok = true;
-
- __END__;
-
- return ok;
-}
-
-
-
-void CvSVM::create_kernel()
-{
- kernel = new CvSVMKernel(¶ms,0);
-}
-
-
-void CvSVM::create_solver( )
-{
- solver = new CvSVMSolver;
-}
-
-
-// switching function
-bool CvSVM::train1( int sample_count, int var_count, const float** samples,
- const void* _responses, double Cp, double Cn,
- CvMemStorage* _storage, double* alpha, double& rho )
-{
- bool ok = false;
-
- //CV_FUNCNAME( "CvSVM::train1" );
-
- __BEGIN__;
-
- CvSVMSolutionInfo si;
- int svm_type = params.svm_type;
-
- si.rho = 0;
-
- ok = svm_type == C_SVC ? solver->solve_c_svc( sample_count, var_count, samples, (schar*)_responses,
- Cp, Cn, _storage, kernel, alpha, si ) :
- svm_type == NU_SVC ? solver->solve_nu_svc( sample_count, var_count, samples, (schar*)_responses,
- _storage, kernel, alpha, si ) :
- svm_type == ONE_CLASS ? solver->solve_one_class( sample_count, var_count, samples,
- _storage, kernel, alpha, si ) :
- svm_type == EPS_SVR ? solver->solve_eps_svr( sample_count, var_count, samples, (float*)_responses,
- _storage, kernel, alpha, si ) :
- svm_type == NU_SVR ? solver->solve_nu_svr( sample_count, var_count, samples, (float*)_responses,
- _storage, kernel, alpha, si ) : false;
-
- rho = si.rho;
-
- __END__;
-
- return ok;
-}
-
-
-bool CvSVM::do_train( int svm_type, int sample_count, int var_count, const float** samples,
- const CvMat* responses, CvMemStorage* temp_storage, double* alpha )
-{
- bool ok = false;
-
- CV_FUNCNAME( "CvSVM::do_train" );
-
- __BEGIN__;
-
- CvSVMDecisionFunc* df = 0;
- const int sample_size = var_count*sizeof(samples[0][0]);
- int i, j, k;
-
- if( svm_type == ONE_CLASS || svm_type == EPS_SVR || svm_type == NU_SVR )
- {
- int sv_count = 0;
-
- CV_CALL( decision_func = df =
- (CvSVMDecisionFunc*)cvAlloc( sizeof(df[0]) ));
-
- df->rho = 0;
- if( !train1( sample_count, var_count, samples, svm_type == ONE_CLASS ? 0 :
- responses->data.i, 0, 0, temp_storage, alpha, df->rho ))
- EXIT;
-
- for( i = 0; i < sample_count; i++ )
- sv_count += fabs(alpha[i]) > 0;
-
- sv_total = df->sv_count = sv_count;
- CV_CALL( df->alpha = (double*)cvMemStorageAlloc( storage, sv_count*sizeof(df->alpha[0])) );
- CV_CALL( sv = (float**)cvMemStorageAlloc( storage, sv_count*sizeof(sv[0])));
-
- for( i = k = 0; i < sample_count; i++ )
- {
- if( fabs(alpha[i]) > 0 )
- {
- CV_CALL( sv[k] = (float*)cvMemStorageAlloc( storage, sample_size ));
- memcpy( sv[k], samples[i], sample_size );
- df->alpha[k++] = alpha[i];
- }
- }
- }
- else
- {
- int class_count = class_labels->cols;
- int* sv_tab = 0;
- const float** temp_samples = 0;
- int* class_ranges = 0;
- schar* temp_y = 0;
- assert( svm_type == CvSVM::C_SVC || svm_type == CvSVM::NU_SVC );
-
- if( svm_type == CvSVM::C_SVC && params.class_weights )
- {
- const CvMat* cw = params.class_weights;
-
- if( !CV_IS_MAT(cw) || cw->cols != 1 && cw->rows != 1 ||
- cw->rows + cw->cols - 1 != class_count ||
- CV_MAT_TYPE(cw->type) != CV_32FC1 && CV_MAT_TYPE(cw->type) != CV_64FC1 )
- CV_ERROR( CV_StsBadArg, "params.class_weights must be 1d floating-point vector "
- "containing as many elements as the number of classes" );
-
- CV_CALL( class_weights = cvCreateMat( cw->rows, cw->cols, CV_64F ));
- CV_CALL( cvConvert( cw, class_weights ));
- CV_CALL( cvScale( class_weights, class_weights, params.C ));
- }
-
- CV_CALL( decision_func = df = (CvSVMDecisionFunc*)cvAlloc(
- (class_count*(class_count-1)/2)*sizeof(df[0])));
-
- CV_CALL( sv_tab = (int*)cvMemStorageAlloc( temp_storage, sample_count*sizeof(sv_tab[0]) ));
- memset( sv_tab, 0, sample_count*sizeof(sv_tab[0]) );
- CV_CALL( class_ranges = (int*)cvMemStorageAlloc( temp_storage,
- (class_count + 1)*sizeof(class_ranges[0])));
- CV_CALL( temp_samples = (const float**)cvMemStorageAlloc( temp_storage,
- sample_count*sizeof(temp_samples[0])));
- CV_CALL( temp_y = (schar*)cvMemStorageAlloc( temp_storage, sample_count));
-
- class_ranges[class_count] = 0;
- cvSortSamplesByClasses( samples, responses, class_ranges, 0 );
- //check that while cross-validation there were the samples from all the classes
- if( class_ranges[class_count] <= 0 )
- CV_ERROR( CV_StsBadArg, "While cross-validation one or more of the classes have "
- "been fell out of the sample. Try to enlarge <CvSVMParams::k_fold>" );
-
- if( svm_type == NU_SVC )
- {
- // check if nu is feasible
- for(i = 0; i < class_count; i++ )
- {
- int ci = class_ranges[i+1] - class_ranges[i];
- for( j = i+1; j< class_count; j++ )
- {
- int cj = class_ranges[j+1] - class_ranges[j];
- if( params.nu*(ci + cj)*0.5 > MIN( ci, cj ) )
- {
- // !!!TODO!!! add some diagnostic
- EXIT; // exit immediately; will release the model and return NULL pointer
- }
- }
- }
- }
-
- // train n*(n-1)/2 classifiers
- for( i = 0; i < class_count; i++ )
- {
- for( j = i+1; j < class_count; j++, df++ )
- {
- int si = class_ranges[i], ci = class_ranges[i+1] - si;
- int sj = class_ranges[j], cj = class_ranges[j+1] - sj;
- double Cp = params.C, Cn = Cp;
- int k1 = 0, sv_count = 0;
-
- for( k = 0; k < ci; k++ )
- {
- temp_samples[k] = samples[si + k];
- temp_y[k] = 1;
- }
-
- for( k = 0; k < cj; k++ )
- {
- temp_samples[ci + k] = samples[sj + k];
- temp_y[ci + k] = -1;
- }
-
- if( class_weights )
- {
- Cp = class_weights->data.db[i];
- Cn = class_weights->data.db[j];
- }
-
- if( !train1( ci + cj, var_count, temp_samples, temp_y,
- Cp, Cn, temp_storage, alpha, df->rho ))
- EXIT;
-
- for( k = 0; k < ci + cj; k++ )
- sv_count += fabs(alpha[k]) > 0;
-
- df->sv_count = sv_count;
-
- CV_CALL( df->alpha = (double*)cvMemStorageAlloc( temp_storage,
- sv_count*sizeof(df->alpha[0])));
- CV_CALL( df->sv_index = (int*)cvMemStorageAlloc( temp_storage,
- sv_count*sizeof(df->sv_index[0])));
-
- for( k = 0; k < ci; k++ )
- {
- if( fabs(alpha[k]) > 0 )
- {
- sv_tab[si + k] = 1;
- df->sv_index[k1] = si + k;
- df->alpha[k1++] = alpha[k];
- }
- }
-
- for( k = 0; k < cj; k++ )
- {
- if( fabs(alpha[ci + k]) > 0 )
- {
- sv_tab[sj + k] = 1;
- df->sv_index[k1] = sj + k;
- df->alpha[k1++] = alpha[ci + k];
- }
- }
- }
- }
-
- // allocate support vectors and initialize sv_tab
- for( i = 0, k = 0; i < sample_count; i++ )
- {
- if( sv_tab[i] )
- sv_tab[i] = ++k;
- }
-
- sv_total = k;
- CV_CALL( sv = (float**)cvMemStorageAlloc( storage, sv_total*sizeof(sv[0])));
-
- for( i = 0, k = 0; i < sample_count; i++ )
- {
- if( sv_tab[i] )
- {
- CV_CALL( sv[k] = (float*)cvMemStorageAlloc( storage, sample_size ));
- memcpy( sv[k], samples[i], sample_size );
- k++;
- }
- }
-
- df = (CvSVMDecisionFunc*)decision_func;
-
- // set sv pointers
- for( i = 0; i < class_count; i++ )
- {
- for( j = i+1; j < class_count; j++, df++ )
- {
- for( k = 0; k < df->sv_count; k++ )
- {
- df->sv_index[k] = sv_tab[df->sv_index[k]]-1;
- assert( (unsigned)df->sv_index[k] < (unsigned)sv_total );
- }
- }
- }
- }
-
- ok = true;
-
- __END__;
-
- return ok;
-}
-
-bool CvSVM::train( const CvMat* _train_data, const CvMat* _responses,
- const CvMat* _var_idx, const CvMat* _sample_idx, CvSVMParams _params )
-{
- bool ok = false;
- CvMat* responses = 0;
- CvMemStorage* temp_storage = 0;
- const float** samples = 0;
-
- CV_FUNCNAME( "CvSVM::train" );
-
- __BEGIN__;
-
- int svm_type, sample_count, var_count, sample_size;
- int block_size = 1 << 16;
- double* alpha;
-
- clear();
- CV_CALL( set_params( _params ));
-
- svm_type = _params.svm_type;
-
- /* Prepare training data and related parameters */
- CV_CALL( cvPrepareTrainData( "CvSVM::train", _train_data, CV_ROW_SAMPLE,
- svm_type != CvSVM::ONE_CLASS ? _responses : 0,
- svm_type == CvSVM::C_SVC ||
- svm_type == CvSVM::NU_SVC ? CV_VAR_CATEGORICAL :
- CV_VAR_ORDERED, _var_idx, _sample_idx,
- false, &samples, &sample_count, &var_count, &var_all,
- &responses, &class_labels, &var_idx ));
-
-
- sample_size = var_count*sizeof(samples[0][0]);
-
- // make the storage block size large enough to fit all
- // the temporary vectors and output support vectors.
- block_size = MAX( block_size, sample_count*(int)sizeof(CvSVMKernelRow));
- block_size = MAX( block_size, sample_count*2*(int)sizeof(double) + 1024 );
- block_size = MAX( block_size, sample_size*2 + 1024 );
-
- CV_CALL( storage = cvCreateMemStorage(block_size));
- CV_CALL( temp_storage = cvCreateChildMemStorage(storage));
- CV_CALL( alpha = (double*)cvMemStorageAlloc(temp_storage, sample_count*sizeof(double)));
-
- create_kernel();
- create_solver();
-
- if( !do_train( svm_type, sample_count, var_count, samples, responses, temp_storage, alpha ))
- EXIT;
-
- ok = true; // model has been trained succesfully
-
- __END__;
-
- delete solver;
- solver = 0;
- cvReleaseMemStorage( &temp_storage );
- cvReleaseMat( &responses );
- cvFree( &samples );
-
- if( cvGetErrStatus() < 0 || !ok )
- clear();
-
- return ok;
-}
-
-bool CvSVM::train_auto( const CvMat* _train_data, const CvMat* _responses,
- const CvMat* _var_idx, const CvMat* _sample_idx, CvSVMParams _params, int k_fold,
- CvParamGrid C_grid, CvParamGrid gamma_grid, CvParamGrid p_grid,
- CvParamGrid nu_grid, CvParamGrid coef_grid, CvParamGrid degree_grid )
-{
- bool ok = false;
- CvMat* responses = 0;
- CvMat* responses_local = 0;
- CvMemStorage* temp_storage = 0;
- const float** samples = 0;
- const float** samples_local = 0;
-
- CV_FUNCNAME( "CvSVM::train_auto" );
- __BEGIN__;
-
- int svm_type, sample_count, var_count, sample_size;
- int block_size = 1 << 16;
- double* alpha;
- int i, k;
- CvRNG rng = cvRNG(-1);
-
- // all steps are logarithmic and must be > 1
- double degree_step = 10, g_step = 10, coef_step = 10, C_step = 10, nu_step = 10, p_step = 10;
- double gamma = 0, C = 0, degree = 0, coef = 0, p = 0, nu = 0;
- double best_degree = 0, best_gamma = 0, best_coef = 0, best_C = 0, best_nu = 0, best_p = 0;
- float min_error = FLT_MAX, error;
-
- if( _params.svm_type == CvSVM::ONE_CLASS )
- {
- if(!train( _train_data, _responses, _var_idx, _sample_idx, _params ))
- EXIT;
- return true;
- }
-
- clear();
-
- if( k_fold < 2 )
- CV_ERROR( CV_StsBadArg, "Parameter <k_fold> must be > 1" );
-
- CV_CALL(set_params( _params ));
- svm_type = _params.svm_type;
-
- // All the parameters except, possibly, <coef0> are positive.
- // <coef0> is nonnegative
- if( C_grid.step <= 1 )
- {
- C_grid.min_val = C_grid.max_val = params.C;
- C_grid.step = 10;
- }
- else
- CV_CALL(C_grid.check());
-
- if( gamma_grid.step <= 1 )
- {
- gamma_grid.min_val = gamma_grid.max_val = params.gamma;
- gamma_grid.step = 10;
- }
- else
- CV_CALL(gamma_grid.check());
-
- if( p_grid.step <= 1 )
- {
- p_grid.min_val = p_grid.max_val = params.p;
- p_grid.step = 10;
- }
- else
- CV_CALL(p_grid.check());
-
- if( nu_grid.step <= 1 )
- {
- nu_grid.min_val = nu_grid.max_val = params.nu;
- nu_grid.step = 10;
- }
- else
- CV_CALL(nu_grid.check());
-
- if( coef_grid.step <= 1 )
- {
- coef_grid.min_val = coef_grid.max_val = params.coef0;
- coef_grid.step = 10;
- }
- else
- CV_CALL(coef_grid.check());
-
- if( degree_grid.step <= 1 )
- {
- degree_grid.min_val = degree_grid.max_val = params.degree;
- degree_grid.step = 10;
- }
- else
- CV_CALL(degree_grid.check());
-
- // these parameters are not used:
- if( params.kernel_type != CvSVM::POLY )
- degree_grid.min_val = degree_grid.max_val = params.degree;
- if( params.kernel_type == CvSVM::LINEAR )
- gamma_grid.min_val = gamma_grid.max_val = params.gamma;
- if( params.kernel_type != CvSVM::POLY && params.kernel_type != CvSVM::SIGMOID )
- coef_grid.min_val = coef_grid.max_val = params.coef0;
- if( svm_type == CvSVM::NU_SVC || svm_type == CvSVM::ONE_CLASS )
- C_grid.min_val = C_grid.max_val = params.C;
- if( svm_type == CvSVM::C_SVC || svm_type == CvSVM::EPS_SVR )
- nu_grid.min_val = nu_grid.max_val = params.nu;
- if( svm_type != CvSVM::EPS_SVR )
- p_grid.min_val = p_grid.max_val = params.p;
-
- CV_ASSERT( g_step > 1 && degree_step > 1 && coef_step > 1);
- CV_ASSERT( p_step > 1 && C_step > 1 && nu_step > 1 );
-
- /* Prepare training data and related parameters */
- CV_CALL(cvPrepareTrainData( "CvSVM::train_auto", _train_data, CV_ROW_SAMPLE,
- svm_type != CvSVM::ONE_CLASS ? _responses : 0,
- svm_type == CvSVM::C_SVC ||
- svm_type == CvSVM::NU_SVC ? CV_VAR_CATEGORICAL :
- CV_VAR_ORDERED, _var_idx, _sample_idx,
- false, &samples, &sample_count, &var_count, &var_all,
- &responses, &class_labels, &var_idx ));
-
- sample_size = var_count*sizeof(samples[0][0]);
-
- // make the storage block size large enough to fit all
- // the temporary vectors and output support vectors.
- block_size = MAX( block_size, sample_count*(int)sizeof(CvSVMKernelRow));
- block_size = MAX( block_size, sample_count*2*(int)sizeof(double) + 1024 );
- block_size = MAX( block_size, sample_size*2 + 1024 );
-
- CV_CALL(storage = cvCreateMemStorage(block_size));
- CV_CALL(temp_storage = cvCreateChildMemStorage(storage));
- CV_CALL(alpha = (double*)cvMemStorageAlloc(temp_storage, sample_count*sizeof(double)));
-
- create_kernel();
- create_solver();
-
- {
- const int testset_size = sample_count/k_fold;
- const int trainset_size = sample_count - testset_size;
- const int last_testset_size = sample_count - testset_size*(k_fold-1);
- const int last_trainset_size = sample_count - last_testset_size;
- const bool is_regression = (svm_type == EPS_SVR) || (svm_type == NU_SVR);
-
- size_t resp_elem_size = CV_ELEM_SIZE(responses->type);
- size_t size = 2*last_trainset_size*sizeof(samples[0]);
-
- samples_local = (const float**) cvAlloc( size );
- memset( samples_local, 0, size );
-
- responses_local = cvCreateMat( 1, trainset_size, CV_MAT_TYPE(responses->type) );
- cvZero( responses_local );
-
- // randomly permute samples and responses
- for( i = 0; i < sample_count; i++ )
- {
- int i1 = cvRandInt( &rng ) % sample_count;
- int i2 = cvRandInt( &rng ) % sample_count;
- const float* temp;
- float t;
- int y;
-
- CV_SWAP( samples[i1], samples[i2], temp );
- if( is_regression )
- CV_SWAP( responses->data.fl[i1], responses->data.fl[i2], t );
- else
- CV_SWAP( responses->data.i[i1], responses->data.i[i2], y );
- }
-
- C = C_grid.min_val;
- do
- {
- params.C = C;
- gamma = gamma_grid.min_val;
- do
- {
- params.gamma = gamma;
- p = p_grid.min_val;
- do
- {
- params.p = p;
- nu = nu_grid.min_val;
- do
- {
- params.nu = nu;
- coef = coef_grid.min_val;
- do
- {
- params.coef0 = coef;
- degree = degree_grid.min_val;
- do
- {
- params.degree = degree;
-
- float** test_samples_ptr = (float**)samples;
- uchar* true_resp = responses->data.ptr;
- int test_size = testset_size;
- int train_size = trainset_size;
-
- error = 0;
- for( k = 0; k < k_fold; k++ )
- {
- memcpy( samples_local, samples, sizeof(samples[0])*test_size*k );
- memcpy( samples_local + test_size*k, test_samples_ptr + test_size,
- sizeof(samples[0])*(sample_count - testset_size*(k+1)) );
-
- memcpy( responses_local->data.ptr, responses->data.ptr, resp_elem_size*test_size*k );
- memcpy( responses_local->data.ptr + resp_elem_size*test_size*k,
- true_resp + resp_elem_size*test_size,
- sizeof(samples[0])*(sample_count - testset_size*(k+1)) );
-
- if( k == k_fold - 1 )
- {
- test_size = last_testset_size;
- train_size = last_trainset_size;
- responses_local->cols = last_trainset_size;
- }
-
- // Train SVM on <train_size> samples
- if( !do_train( svm_type, train_size, var_count,
- (const float**)samples_local, responses_local, temp_storage, alpha ) )
- EXIT;
-
- // Compute test set error on <test_size> samples
- CvMat s = cvMat( 1, var_count, CV_32FC1 );
- for( i = 0; i < test_size; i++, true_resp += resp_elem_size, test_samples_ptr++ )
- {
- float resp;
- s.data.fl = *test_samples_ptr;
- resp = predict( &s );
- error += is_regression ? powf( resp - *(float*)true_resp, 2 )
- : ((int)resp != *(int*)true_resp);
- }
- }
- if( min_error > error )
- {
- min_error = error;
- best_degree = degree;
- best_gamma = gamma;
- best_coef = coef;
- best_C = C;
- best_nu = nu;
- best_p = p;
- }
- degree *= degree_grid.step;
- }
- while( degree < degree_grid.max_val );
- coef *= coef_grid.step;
- }
- while( coef < coef_grid.max_val );
- nu *= nu_grid.step;
- }
- while( nu < nu_grid.max_val );
- p *= p_grid.step;
- }
- while( p < p_grid.max_val );
- gamma *= gamma_grid.step;
- }
- while( gamma < gamma_grid.max_val );
- C *= C_grid.step;
- }
- while( C < C_grid.max_val );
- }
-
- min_error /= (float) sample_count;
-
- params.C = best_C;
- params.nu = best_nu;
- params.p = best_p;
- params.gamma = best_gamma;
- params.degree = best_degree;
- params.coef0 = best_coef;
-
- CV_CALL(ok = do_train( svm_type, sample_count, var_count, samples, responses, temp_storage, alpha ));
-
- __END__;
-
- delete solver;
- solver = 0;
- cvReleaseMemStorage( &temp_storage );
- cvReleaseMat( &responses );
- cvReleaseMat( &responses_local );
- cvFree( &samples );
- cvFree( &samples_local );
-
- if( cvGetErrStatus() < 0 || !ok )
- clear();
-
- return ok;
-}
-
-float CvSVM::predict( const CvMat* sample ) const
-{
- bool local_alloc = 0;
- float result = 0;
- float* row_sample = 0;
- Qfloat* buffer = 0;
-
- CV_FUNCNAME( "CvSVM::predict" );
-
- __BEGIN__;
-
- int class_count;
- int var_count, buf_sz;
-
- if( !kernel )
- CV_ERROR( CV_StsBadArg, "The SVM should be trained first" );
-
- class_count = class_labels ? class_labels->cols :
- params.svm_type == ONE_CLASS ? 1 : 0;
-
- CV_CALL( cvPreparePredictData( sample, var_all, var_idx,
- class_count, 0, &row_sample ));
-
- var_count = get_var_count();
-
- buf_sz = sv_total*sizeof(buffer[0]) + (class_count+1)*sizeof(int);
- if( buf_sz <= CV_MAX_LOCAL_SIZE )
- {
- CV_CALL( buffer = (Qfloat*)cvStackAlloc( buf_sz ));
- local_alloc = 1;
- }
- else
- CV_CALL( buffer = (Qfloat*)cvAlloc( buf_sz ));
-
- if( params.svm_type == EPS_SVR ||
- params.svm_type == NU_SVR ||
- params.svm_type == ONE_CLASS )
- {
- CvSVMDecisionFunc* df = (CvSVMDecisionFunc*)decision_func;
- int i, sv_count = df->sv_count;
- double sum = -df->rho;
-
- kernel->calc( sv_count, var_count, (const float**)sv, row_sample, buffer );
- for( i = 0; i < sv_count; i++ )
- sum += buffer[i]*df->alpha[i];
-
- result = params.svm_type == ONE_CLASS ? (float)(sum > 0) : (float)sum;
- }
- else if( params.svm_type == C_SVC ||
- params.svm_type == NU_SVC )
- {
- CvSVMDecisionFunc* df = (CvSVMDecisionFunc*)decision_func;
- int* vote = (int*)(buffer + sv_total);
- int i, j, k;
-
- memset( vote, 0, class_count*sizeof(vote[0]));
- kernel->calc( sv_total, var_count, (const float**)sv, row_sample, buffer );
-
- for( i = 0; i < class_count; i++ )
- {
- for( j = i+1; j < class_count; j++, df++ )
- {
- double sum = -df->rho;
- int sv_count = df->sv_count;
- for( k = 0; k < sv_count; k++ )
- sum += df->alpha[k]*buffer[df->sv_index[k]];
-
- vote[sum > 0 ? i : j]++;
- }
- }
-
- for( i = 1, k = 0; i < class_count; i++ )
- {
- if( vote[i] > vote[k] )
- k = i;
- }
-
- result = (float)(class_labels->data.i[k]);
- }
- else
- CV_ERROR( CV_StsBadArg, "INTERNAL ERROR: Unknown SVM type, "
- "the SVM structure is probably corrupted" );
-
- __END__;
-
- if( sample && (!CV_IS_MAT(sample) || sample->data.fl != row_sample) )
- cvFree( &row_sample );
-
- if( !local_alloc )
- cvFree( &buffer );
-
- return result;
-}
-
-
-void CvSVM::write_params( CvFileStorage* fs )
-{
- //CV_FUNCNAME( "CvSVM::write_params" );
-
- __BEGIN__;
-
- int svm_type = params.svm_type;
- int kernel_type = params.kernel_type;
-
- const char* svm_type_str =
- svm_type == CvSVM::C_SVC ? "C_SVC" :
- svm_type == CvSVM::NU_SVC ? "NU_SVC" :
- svm_type == CvSVM::ONE_CLASS ? "ONE_CLASS" :
- svm_type == CvSVM::EPS_SVR ? "EPS_SVR" :
- svm_type == CvSVM::NU_SVR ? "NU_SVR" : 0;
- const char* kernel_type_str =
- kernel_type == CvSVM::LINEAR ? "LINEAR" :
- kernel_type == CvSVM::POLY ? "POLY" :
- kernel_type == CvSVM::RBF ? "RBF" :
- kernel_type == CvSVM::SIGMOID ? "SIGMOID" : 0;
-
- if( svm_type_str )
- cvWriteString( fs, "svm_type", svm_type_str );
- else
- cvWriteInt( fs, "svm_type", svm_type );
-
- // save kernel
- cvStartWriteStruct( fs, "kernel", CV_NODE_MAP + CV_NODE_FLOW );
-
- if( kernel_type_str )
- cvWriteString( fs, "type", kernel_type_str );
- else
- cvWriteInt( fs, "type", kernel_type );
-
- if( kernel_type == CvSVM::POLY || !kernel_type_str )
- cvWriteReal( fs, "degree", params.degree );
-
- if( kernel_type != CvSVM::LINEAR || !kernel_type_str )
- cvWriteReal( fs, "gamma", params.gamma );
-
- if( kernel_type == CvSVM::POLY || kernel_type == CvSVM::SIGMOID || !kernel_type_str )
- cvWriteReal( fs, "coef0", params.coef0 );
-
- cvEndWriteStruct(fs);
-
- if( svm_type == CvSVM::C_SVC || svm_type == CvSVM::EPS_SVR ||
- svm_type == CvSVM::NU_SVR || !svm_type_str )
- cvWriteReal( fs, "C", params.C );
-
- if( svm_type == CvSVM::NU_SVC || svm_type == CvSVM::ONE_CLASS ||
- svm_type == CvSVM::NU_SVR || !svm_type_str )
- cvWriteReal( fs, "nu", params.nu );
-
- if( svm_type == CvSVM::EPS_SVR || !svm_type_str )
- cvWriteReal( fs, "p", params.p );
-
- 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 );
-
- __END__;
-}
-
-
-void CvSVM::write( CvFileStorage* fs, const char* name )
-{
- CV_FUNCNAME( "CvSVM::write" );
-
- __BEGIN__;
-
- int i, var_count = get_var_count(), df_count, class_count;
- const CvSVMDecisionFunc* df = decision_func;
-
- cvStartWriteStruct( fs, name, CV_NODE_MAP, CV_TYPE_NAME_ML_SVM );
-
- write_params( fs );
-
- cvWriteInt( fs, "var_all", var_all );
- cvWriteInt( fs, "var_count", var_count );
-
- class_count = class_labels ? class_labels->cols :
- params.svm_type == CvSVM::ONE_CLASS ? 1 : 0;
-
- if( class_count )
- {
- cvWriteInt( fs, "class_count", class_count );
-
- if( class_labels )
- cvWrite( fs, "class_labels", class_labels );
-
- if( class_weights )
- cvWrite( fs, "class_weights", class_weights );
- }
-
- if( var_idx )
- cvWrite( fs, "var_idx", var_idx );
-
- // write the joint collection of support vectors
- cvWriteInt( fs, "sv_total", sv_total );
- cvStartWriteStruct( fs, "support_vectors", CV_NODE_SEQ );
- for( i = 0; i < sv_total; i++ )
- {
- cvStartWriteStruct( fs, 0, CV_NODE_SEQ + CV_NODE_FLOW );
- cvWriteRawData( fs, sv[i], var_count, "f" );
- cvEndWriteStruct( fs );
- }
-
- cvEndWriteStruct( fs );
-
- // write decision functions
- df_count = class_count > 1 ? class_count*(class_count-1)/2 : 1;
- df = decision_func;
-
- cvStartWriteStruct( fs, "decision_functions", CV_NODE_SEQ );
- for( i = 0; i < df_count; i++ )
- {
- int sv_count = df[i].sv_count;
- cvStartWriteStruct( fs, 0, CV_NODE_MAP );
- cvWriteInt( fs, "sv_count", sv_count );
- cvWriteReal( fs, "rho", df[i].rho );
- cvStartWriteStruct( fs, "alpha", CV_NODE_SEQ+CV_NODE_FLOW );
- cvWriteRawData( fs, df[i].alpha, df[i].sv_count, "d" );
- cvEndWriteStruct( fs );
- if( class_count > 1 )
- {
- cvStartWriteStruct( fs, "index", CV_NODE_SEQ+CV_NODE_FLOW );
- cvWriteRawData( fs, df[i].sv_index, df[i].sv_count, "i" );
- cvEndWriteStruct( fs );
- }
- else
- CV_ASSERT( sv_count == sv_total );
- cvEndWriteStruct( fs );
- }
- cvEndWriteStruct( fs );
- cvEndWriteStruct( fs );
-
- __END__;
-}
-
-
-void CvSVM::read_params( CvFileStorage* fs, CvFileNode* svm_node )
-{
- CV_FUNCNAME( "CvSVM::read_params" );
-
- __BEGIN__;
-
- int svm_type, kernel_type;
- CvSVMParams _params;
-
- CvFileNode* tmp_node = cvGetFileNodeByName( fs, svm_node, "svm_type" );
- CvFileNode* kernel_node;
- if( !tmp_node )
- CV_ERROR( CV_StsBadArg, "svm_type tag is not found" );
-
- if( CV_NODE_TYPE(tmp_node->tag) == CV_NODE_INT )
- svm_type = cvReadInt( tmp_node, -1 );
- else
- {
- const char* svm_type_str = cvReadString( tmp_node, "" );
- svm_type =
- strcmp( svm_type_str, "C_SVC" ) == 0 ? CvSVM::C_SVC :
- strcmp( svm_type_str, "NU_SVC" ) == 0 ? CvSVM::NU_SVC :
- strcmp( svm_type_str, "ONE_CLASS" ) == 0 ? CvSVM::ONE_CLASS :
- strcmp( svm_type_str, "EPS_SVR" ) == 0 ? CvSVM::EPS_SVR :
- strcmp( svm_type_str, "NU_SVR" ) == 0 ? CvSVM::NU_SVR : -1;
-
- if( svm_type < 0 )
- CV_ERROR( CV_StsParseError, "Missing of invalid SVM type" );
- }
-
- kernel_node = cvGetFileNodeByName( fs, svm_node, "kernel" );
- if( !kernel_node )
- CV_ERROR( CV_StsParseError, "SVM kernel tag is not found" );
-
- tmp_node = cvGetFileNodeByName( fs, kernel_node, "type" );
- if( !tmp_node )
- CV_ERROR( CV_StsParseError, "SVM kernel type tag is not found" );
-
- if( CV_NODE_TYPE(tmp_node->tag) == CV_NODE_INT )
- kernel_type = cvReadInt( tmp_node, -1 );
- else
- {
- const char* kernel_type_str = cvReadString( tmp_node, "" );
- kernel_type =
- strcmp( kernel_type_str, "LINEAR" ) == 0 ? CvSVM::LINEAR :
- strcmp( kernel_type_str, "POLY" ) == 0 ? CvSVM::POLY :
- strcmp( kernel_type_str, "RBF" ) == 0 ? CvSVM::RBF :
- strcmp( kernel_type_str, "SIGMOID" ) == 0 ? CvSVM::SIGMOID : -1;
-
- if( kernel_type < 0 )
- CV_ERROR( CV_StsParseError, "Missing of invalid SVM kernel type" );
- }
-
- _params.svm_type = svm_type;
- _params.kernel_type = kernel_type;
- _params.degree = cvReadRealByName( fs, kernel_node, "degree", 0 );
- _params.gamma = cvReadRealByName( fs, kernel_node, "gamma", 0 );
- _params.coef0 = cvReadRealByName( fs, kernel_node, "coef0", 0 );
-
- _params.C = cvReadRealByName( fs, svm_node, "C", 0 );
- _params.nu = cvReadRealByName( fs, svm_node, "nu", 0 );
- _params.p = cvReadRealByName( fs, svm_node, "p", 0 );
- _params.class_weights = 0;
-
- tmp_node = cvGetFileNodeByName( fs, svm_node, "term_criteria" );
- if( tmp_node )
- {
- _params.term_crit.epsilon = cvReadRealByName( fs, tmp_node, "epsilon", -1. );
- _params.term_crit.max_iter = cvReadIntByName( fs, tmp_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);
- }
- else
- _params.term_crit = cvTermCriteria( CV_TERMCRIT_EPS + CV_TERMCRIT_ITER, 1000, FLT_EPSILON );
-
- set_params( _params );
-
- __END__;
-}
-
-
-void CvSVM::read( CvFileStorage* fs, CvFileNode* svm_node )
-{
- const double not_found_dbl = DBL_MAX;
-
- CV_FUNCNAME( "CvSVM::read" );
-
- __BEGIN__;
-
- int i, var_count, df_count, class_count;
- int block_size = 1 << 16, sv_size;
- CvFileNode *sv_node, *df_node;
- CvSVMDecisionFunc* df;
- CvSeqReader reader;
-
- if( !svm_node )
- CV_ERROR( CV_StsParseError, "The requested element is not found" );
-
- clear();
-
- // read SVM parameters
- read_params( fs, svm_node );
-
- // and top-level data
- sv_total = cvReadIntByName( fs, svm_node, "sv_total", -1 );
- var_all = cvReadIntByName( fs, svm_node, "var_all", -1 );
- var_count = cvReadIntByName( fs, svm_node, "var_count", var_all );
- class_count = cvReadIntByName( fs, svm_node, "class_count", 0 );
-
- if( sv_total <= 0 || var_all <= 0 || var_count <= 0 || var_count > var_all || class_count < 0 )
- CV_ERROR( CV_StsParseError, "SVM model data is invalid, check sv_count, var_* and class_count tags" );
-
- CV_CALL( class_labels = (CvMat*)cvReadByName( fs, svm_node, "class_labels" ));
- CV_CALL( class_weights = (CvMat*)cvReadByName( fs, svm_node, "class_weights" ));
- CV_CALL( var_idx = (CvMat*)cvReadByName( fs, svm_node, "comp_idx" ));
-
- if( class_count > 1 && (!class_labels ||
- !CV_IS_MAT(class_labels) || class_labels->cols != class_count))
- CV_ERROR( CV_StsParseError, "Array of class labels is missing or invalid" );
-
- if( var_count < var_all && (!var_idx || !CV_IS_MAT(var_idx) || var_idx->cols != var_count) )
- CV_ERROR( CV_StsParseError, "var_idx array is missing or invalid" );
-
- // read support vectors
- sv_node = cvGetFileNodeByName( fs, svm_node, "support_vectors" );
- if( !sv_node || !CV_NODE_IS_SEQ(sv_node->tag))
- CV_ERROR( CV_StsParseError, "Missing or invalid sequence of support vectors" );
-
- block_size = MAX( block_size, sv_total*(int)sizeof(CvSVMKernelRow));
- block_size = MAX( block_size, sv_total*2*(int)sizeof(double));
- block_size = MAX( block_size, var_all*(int)sizeof(double));
- CV_CALL( storage = cvCreateMemStorage( block_size ));
- CV_CALL( sv = (float**)cvMemStorageAlloc( storage,
- sv_total*sizeof(sv[0]) ));
-
- CV_CALL( cvStartReadSeq( sv_node->data.seq, &reader, 0 ));
- sv_size = var_count*sizeof(sv[0][0]);
-
- for( i = 0; i < sv_total; i++ )
- {
- CvFileNode* sv_elem = (CvFileNode*)reader.ptr;
- CV_ASSERT( var_count == 1 || (CV_NODE_IS_SEQ(sv_elem->tag) &&
- sv_elem->data.seq->total == var_count) );
-
- CV_CALL( sv[i] = (float*)cvMemStorageAlloc( storage, sv_size ));
- CV_CALL( cvReadRawData( fs, sv_elem, sv[i], "f" ));
- CV_NEXT_SEQ_ELEM( sv_node->data.seq->elem_size, reader );
- }
-
- // read decision functions
- df_count = class_count > 1 ? class_count*(class_count-1)/2 : 1;
- df_node = cvGetFileNodeByName( fs, svm_node, "decision_functions" );
- if( !df_node || !CV_NODE_IS_SEQ(df_node->tag) ||
- df_node->data.seq->total != df_count )
- CV_ERROR( CV_StsParseError, "decision_functions is missing or is not a collection "
- "or has a wrong number of elements" );
-
- CV_CALL( df = decision_func = (CvSVMDecisionFunc*)cvAlloc( df_count*sizeof(df[0]) ));
- cvStartReadSeq( df_node->data.seq, &reader, 0 );
-
- for( i = 0; i < df_count; i++ )
- {
- CvFileNode* df_elem = (CvFileNode*)reader.ptr;
- CvFileNode* alpha_node = cvGetFileNodeByName( fs, df_elem, "alpha" );
-
- int sv_count = cvReadIntByName( fs, df_elem, "sv_count", -1 );
- if( sv_count <= 0 )
- CV_ERROR( CV_StsParseError, "sv_count is missing or non-positive" );
- df[i].sv_count = sv_count;
-
- df[i].rho = cvReadRealByName( fs, df_elem, "rho", not_found_dbl );
- if( fabs(df[i].rho - not_found_dbl) < DBL_EPSILON )
- CV_ERROR( CV_StsParseError, "rho is missing" );
-
- if( !alpha_node )
- CV_ERROR( CV_StsParseError, "alpha is missing in the decision function" );
-
- CV_CALL( df[i].alpha = (double*)cvMemStorageAlloc( storage,
- sv_count*sizeof(df[i].alpha[0])));
- CV_ASSERT( sv_count == 1 || CV_NODE_IS_SEQ(alpha_node->tag) &&
- alpha_node->data.seq->total == sv_count );
- CV_CALL( cvReadRawData( fs, alpha_node, df[i].alpha, "d" ));
-
- if( class_count > 1 )
- {
- CvFileNode* index_node = cvGetFileNodeByName( fs, df_elem, "index" );
- if( !index_node )
- CV_ERROR( CV_StsParseError, "index is missing in the decision function" );
- CV_CALL( df[i].sv_index = (int*)cvMemStorageAlloc( storage,
- sv_count*sizeof(df[i].sv_index[0])));
- CV_ASSERT( sv_count == 1 || CV_NODE_IS_SEQ(index_node->tag) &&
- index_node->data.seq->total == sv_count );
- CV_CALL( cvReadRawData( fs, index_node, df[i].sv_index, "i" ));
- }
- else
- df[i].sv_index = 0;
-
- CV_NEXT_SEQ_ELEM( df_node->data.seq->elem_size, reader );
- }
-
- create_kernel();
-
- __END__;
-}
-
-#if 0
-
-static void*
-icvCloneSVM( const void* _src )
-{
- CvSVMModel* dst = 0;
-
- CV_FUNCNAME( "icvCloneSVM" );
-
- __BEGIN__;
-
- const CvSVMModel* src = (const CvSVMModel*)_src;
- int var_count, class_count;
- int i, sv_total, df_count;
- int sv_size;
-
- if( !CV_IS_SVM(src) )
- CV_ERROR( !src ? CV_StsNullPtr : CV_StsBadArg, "Input pointer is NULL or invalid" );
-
- // 0. create initial CvSVMModel structure
- CV_CALL( dst = icvCreateSVM() );
- dst->params = src->params;
- dst->params.weight_labels = 0;
- dst->params.weights = 0;
-
- dst->var_all = src->var_all;
- if( src->class_labels )
- dst->class_labels = cvCloneMat( src->class_labels );
- if( src->class_weights )
- dst->class_weights = cvCloneMat( src->class_weights );
- if( src->comp_idx )
- dst->comp_idx = cvCloneMat( src->comp_idx );
-
- var_count = src->comp_idx ? src->comp_idx->cols : src->var_all;
- class_count = src->class_labels ? src->class_labels->cols :
- src->params.svm_type == CvSVM::ONE_CLASS ? 1 : 0;
- sv_total = dst->sv_total = src->sv_total;
- CV_CALL( dst->storage = cvCreateMemStorage( src->storage->block_size ));
- CV_CALL( dst->sv = (float**)cvMemStorageAlloc( dst->storage,
- sv_total*sizeof(dst->sv[0]) ));
-
- sv_size = var_count*sizeof(dst->sv[0][0]);
-
- for( i = 0; i < sv_total; i++ )
- {
- CV_CALL( dst->sv[i] = (float*)cvMemStorageAlloc( dst->storage, sv_size ));
- memcpy( dst->sv[i], src->sv[i], sv_size );
- }
-
- df_count = class_count > 1 ? class_count*(class_count-1)/2 : 1;
-
- CV_CALL( dst->decision_func = cvAlloc( df_count*sizeof(CvSVMDecisionFunc) ));
-
- for( i = 0; i < df_count; i++ )
- {
- const CvSVMDecisionFunc *sdf =
- (const CvSVMDecisionFunc*)src->decision_func+i;
- CvSVMDecisionFunc *ddf =
- (CvSVMDecisionFunc*)dst->decision_func+i;
- int sv_count = sdf->sv_count;
- ddf->sv_count = sv_count;
- ddf->rho = sdf->rho;
- CV_CALL( ddf->alpha = (double*)cvMemStorageAlloc( dst->storage,
- sv_count*sizeof(ddf->alpha[0])));
- memcpy( ddf->alpha, sdf->alpha, sv_count*sizeof(ddf->alpha[0]));
-
- if( class_count > 1 )
- {
- CV_CALL( ddf->sv_index = (int*)cvMemStorageAlloc( dst->storage,
- sv_count*sizeof(ddf->sv_index[0])));
- memcpy( ddf->sv_index, sdf->sv_index, sv_count*sizeof(ddf->sv_index[0]));
- }
- else
- ddf->sv_index = 0;
- }
-
- __END__;
-
- if( cvGetErrStatus() < 0 && dst )
- icvReleaseSVM( &dst );
-
- return dst;
-}
-
-static int icvRegisterSVMType()
-{
- CvTypeInfo info;
- memset( &info, 0, sizeof(info) );
-
- info.flags = 0;
- info.header_size = sizeof( info );
- info.is_instance = icvIsSVM;
- info.release = (CvReleaseFunc)icvReleaseSVM;
- info.read = icvReadSVM;
- info.write = icvWriteSVM;
- info.clone = icvCloneSVM;
- info.type_name = CV_TYPE_NAME_ML_SVM;
- cvRegisterType( &info );
-
- return 1;
-}
-
-
-static int svm = icvRegisterSVMType();
-
-/* The function trains SVM model with optimal parameters, obtained by using cross-validation.
-The parameters to be estimated should be indicated by setting theirs values to FLT_MAX.
-The optimal parameters are saved in <model_params> */
-CV_IMPL CvStatModel*
-cvTrainSVM_CrossValidation( const CvMat* train_data, int tflag,
- const CvMat* responses,
- CvStatModelParams* model_params,
- const CvStatModelParams* cross_valid_params,
- const CvMat* comp_idx,
- const CvMat* sample_idx,
- const CvParamGrid* degree_grid,
- const CvParamGrid* gamma_grid,
- const CvParamGrid* coef_grid,
- const CvParamGrid* C_grid,
- const CvParamGrid* nu_grid,
- const CvParamGrid* p_grid )
-{
- CvStatModel* svm = 0;
-
- CV_FUNCNAME("cvTainSVMCrossValidation");
- __BEGIN__;
-
- double degree_step = 7,
- g_step = 15,
- coef_step = 14,
- C_step = 20,
- nu_step = 5,
- p_step = 7; // all steps must be > 1
- double degree_begin = 0.01, degree_end = 2;
- double g_begin = 1e-5, g_end = 0.5;
- double coef_begin = 0.1, coef_end = 300;
- double C_begin = 0.1, C_end = 6000;
- double nu_begin = 0.01, nu_end = 0.4;
- double p_begin = 0.01, p_end = 100;
-
- double rate = 0, gamma = 0, C = 0, degree = 0, coef = 0, p = 0, nu = 0;
-
- double best_rate = 0;
- double best_degree = degree_begin;
- double best_gamma = g_begin;
- double best_coef = coef_begin;
- double best_C = C_begin;
- double best_nu = nu_begin;
- double best_p = p_begin;
-
- CvSVMModelParams svm_params, *psvm_params;
- CvCrossValidationParams* cv_params = (CvCrossValidationParams*)cross_valid_params;
- int svm_type, kernel;
- int is_regression;
-
- if( !model_params )
- CV_ERROR( CV_StsBadArg, "" );
- if( !cv_params )
- CV_ERROR( CV_StsBadArg, "" );
-
- svm_params = *(CvSVMModelParams*)model_params;
- psvm_params = (CvSVMModelParams*)model_params;
- svm_type = svm_params.svm_type;
- kernel = svm_params.kernel_type;
-
- svm_params.degree = svm_params.degree > 0 ? svm_params.degree : 1;
- svm_params.gamma = svm_params.gamma > 0 ? svm_params.gamma : 1;
- svm_params.coef0 = svm_params.coef0 > 0 ? svm_params.coef0 : 1e-6;
- svm_params.C = svm_params.C > 0 ? svm_params.C : 1;
- svm_params.nu = svm_params.nu > 0 ? svm_params.nu : 1;
- svm_params.p = svm_params.p > 0 ? svm_params.p : 1;
-
- if( degree_grid )
- {
- if( !(degree_grid->max_val == 0 && degree_grid->min_val == 0 &&
- degree_grid->step == 0) )
- {
- if( degree_grid->min_val > degree_grid->max_val )
- CV_ERROR( CV_StsBadArg,
- "low bound of grid should be less then the upper one");
- if( degree_grid->step <= 1 )
- CV_ERROR( CV_StsBadArg, "grid step should be greater 1" );
- degree_begin = degree_grid->min_val;
- degree_end = degree_grid->max_val;
- degree_step = degree_grid->step;
- }
- }
- else
- degree_begin = degree_end = svm_params.degree;
-
- if( gamma_grid )
- {
- if( !(gamma_grid->max_val == 0 && gamma_grid->min_val == 0 &&
- gamma_grid->step == 0) )
- {
- if( gamma_grid->min_val > gamma_grid->max_val )
- CV_ERROR( CV_StsBadArg,
- "low bound of grid should be less then the upper one");
- if( gamma_grid->step <= 1 )
- CV_ERROR( CV_StsBadArg, "grid step should be greater 1" );
- g_begin = gamma_grid->min_val;
- g_end = gamma_grid->max_val;
- g_step = gamma_grid->step;
- }
- }
- else
- g_begin = g_end = svm_params.gamma;
-
- if( coef_grid )
- {
- if( !(coef_grid->max_val == 0 && coef_grid->min_val == 0 &&
- coef_grid->step == 0) )
- {
- if( coef_grid->min_val > coef_grid->max_val )
- CV_ERROR( CV_StsBadArg,
- "low bound of grid should be less then the upper one");
- if( coef_grid->step <= 1 )
- CV_ERROR( CV_StsBadArg, "grid step should be greater 1" );
- coef_begin = coef_grid->min_val;
- coef_end = coef_grid->max_val;
- coef_step = coef_grid->step;
- }
- }
- else
- coef_begin = coef_end = svm_params.coef0;
-
- if( C_grid )
- {
- if( !(C_grid->max_val == 0 && C_grid->min_val == 0 && C_grid->step == 0))
- {
- if( C_grid->min_val > C_grid->max_val )
- CV_ERROR( CV_StsBadArg,
- "low bound of grid should be less then the upper one");
- if( C_grid->step <= 1 )
- CV_ERROR( CV_StsBadArg, "grid step should be greater 1" );
- C_begin = C_grid->min_val;
- C_end = C_grid->max_val;
- C_step = C_grid->step;
- }
- }
- else
- C_begin = C_end = svm_params.C;
-
- if( nu_grid )
- {
- if(!(nu_grid->max_val == 0 && nu_grid->min_val == 0 && nu_grid->step==0))
- {
- if( nu_grid->min_val > nu_grid->max_val )
- CV_ERROR( CV_StsBadArg,
- "low bound of grid should be less then the upper one");
- if( nu_grid->step <= 1 )
- CV_ERROR( CV_StsBadArg, "grid step should be greater 1" );
- nu_begin = nu_grid->min_val;
- nu_end = nu_grid->max_val;
- nu_step = nu_grid->step;
- }
- }
- else
- nu_begin = nu_end = svm_params.nu;
-
- if( p_grid )
- {
- if( !(p_grid->max_val == 0 && p_grid->min_val == 0 && p_grid->step == 0))
- {
- if( p_grid->min_val > p_grid->max_val )
- CV_ERROR( CV_StsBadArg,
- "low bound of grid should be less then the upper one");
- if( p_grid->step <= 1 )
- CV_ERROR( CV_StsBadArg, "grid step should be greater 1" );
- p_begin = p_grid->min_val;
- p_end = p_grid->max_val;
- p_step = p_grid->step;
- }
- }
- else
- p_begin = p_end = svm_params.p;
-
- // these parameters are not used:
- if( kernel != CvSVM::POLY )
- degree_begin = degree_end = svm_params.degree;
-
- if( kernel == CvSVM::LINEAR )
- g_begin = g_end = svm_params.gamma;
-
- if( kernel != CvSVM::POLY && kernel != CvSVM::SIGMOID )
- coef_begin = coef_end = svm_params.coef0;
-
- if( svm_type == CvSVM::NU_SVC || svm_type == CvSVM::ONE_CLASS )
- C_begin = C_end = svm_params.C;
-
- if( svm_type == CvSVM::C_SVC || svm_type == CvSVM::EPS_SVR )
- nu_begin = nu_end = svm_params.nu;
-
- if( svm_type != CvSVM::EPS_SVR )
- p_begin = p_end = svm_params.p;
-
- is_regression = cv_params->is_regression;
- best_rate = is_regression ? FLT_MAX : 0;
-
- assert( g_step > 1 && degree_step > 1 && coef_step > 1);
- assert( p_step > 1 && C_step > 1 && nu_step > 1 );
-
- for( degree = degree_begin; degree <= degree_end; degree *= degree_step )
- {
- svm_params.degree = degree;
- //printf("degree = %.3f\n", degree );
- for( gamma= g_begin; gamma <= g_end; gamma *= g_step )
- {
- svm_params.gamma = gamma;
- //printf(" gamma = %.3f\n", gamma );
- for( coef = coef_begin; coef <= coef_end; coef *= coef_step )
- {
- svm_params.coef0 = coef;
- //printf(" coef = %.3f\n", coef );
- for( C = C_begin; C <= C_end; C *= C_step )
- {
- svm_params.C = C;
- //printf(" C = %.3f\n", C );
- for( nu = nu_begin; nu <= nu_end; nu *= nu_step )
- {
- svm_params.nu = nu;
- //printf(" nu = %.3f\n", nu );
- for( p = p_begin; p <= p_end; p *= p_step )
- {
- int well;
- svm_params.p = p;
- //printf(" p = %.3f\n", p );
-
- CV_CALL(rate = cvCrossValidation( train_data, tflag, responses, &cvTrainSVM,
- cross_valid_params, (CvStatModelParams*)&svm_params, comp_idx, sample_idx ));
-
- well = rate > best_rate && !is_regression || rate < best_rate && is_regression;
- if( well || (rate == best_rate && C < best_C) )
- {
- best_rate = rate;
- best_degree = degree;
- best_gamma = gamma;
- best_coef = coef;
- best_C = C;
- best_nu = nu;
- best_p = p;
- }
- //printf(" rate = %.2f\n", rate );
- }
- }
- }
- }
- }
- }
- //printf("The best:\nrate = %.2f%% degree = %f gamma = %f coef = %f c = %f nu = %f p = %f\n",
- // best_rate, best_degree, best_gamma, best_coef, best_C, best_nu, best_p );
-
- psvm_params->C = best_C;
- psvm_params->nu = best_nu;
- psvm_params->p = best_p;
- psvm_params->gamma = best_gamma;
- psvm_params->degree = best_degree;
- psvm_params->coef0 = best_coef;
-
- CV_CALL(svm = cvTrainSVM( train_data, tflag, responses, model_params, comp_idx, sample_idx ));
-
- __END__;
-
- return svm;
-}
-
-#endif
-
-/* End of file. */
-