1
/*M///////////////////////////////////////////////////////////////////////////////////////
3
// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
5
// By downloading, copying, installing or using the software you agree to this license.
6
// If you do not agree to this license, do not download, install,
7
// copy or use the software.
10
// Intel License Agreement
12
// Copyright (C) 2000, Intel Corporation, all rights reserved.
13
// Third party copyrights are property of their respective owners.
15
// Redistribution and use in source and binary forms, with or without modification,
16
// are permitted provided that the following conditions are met:
18
// * Redistribution's of source code must retain the above copyright notice,
19
// this list of conditions and the following disclaimer.
21
// * Redistribution's in binary form must reproduce the above copyright notice,
22
// this list of conditions and the following disclaimer in the documentation
23
// and/or other materials provided with the distribution.
25
// * The name of Intel Corporation may not be used to endorse or promote products
26
// derived from this software without specific prior written permission.
28
// This software is provided by the copyright holders and contributors "as is" and
29
// any express or implied warranties, including, but not limited to, the implied
30
// warranties of merchantability and fitness for a particular purpose are disclaimed.
31
// In no event shall the Intel Corporation or contributors be liable for any direct,
32
// indirect, incidental, special, exemplary, or consequential damages
33
// (including, but not limited to, procurement of substitute goods or services;
34
// loss of use, data, or profits; or business interruption) however caused
35
// and on any theory of liability, whether in contract, strict liability,
36
// or tort (including negligence or otherwise) arising in any way out of
37
// the use of this software, even if advised of the possibility of such damage.
41
#include "old_ml_precomp.hpp"
44
log_ratio( double val )
46
const double eps = 1e-5;
48
val = MAX( val, eps );
49
val = MIN( val, 1. - eps );
50
return log( val/(1. - val) );
54
CvBoostParams::CvBoostParams()
56
boost_type = CvBoost::REAL;
58
weight_trim_rate = 0.95;
64
CvBoostParams::CvBoostParams( int _boost_type, int _weak_count,
65
double _weight_trim_rate, int _max_depth,
66
bool _use_surrogates, const float* _priors )
68
boost_type = _boost_type;
69
weak_count = _weak_count;
70
weight_trim_rate = _weight_trim_rate;
71
split_criteria = CvBoost::DEFAULT;
73
max_depth = _max_depth;
74
use_surrogates = _use_surrogates;
80
///////////////////////////////// CvBoostTree ///////////////////////////////////
82
CvBoostTree::CvBoostTree()
88
CvBoostTree::~CvBoostTree()
103
CvBoostTree::train( CvDTreeTrainData* _train_data,
104
const CvMat* _subsample_idx, CvBoost* _ensemble )
107
ensemble = _ensemble;
110
return do_train( _subsample_idx );
115
CvBoostTree::train( const CvMat*, int, const CvMat*, const CvMat*,
116
const CvMat*, const CvMat*, const CvMat*, CvDTreeParams )
124
CvBoostTree::train( CvDTreeTrainData*, const CvMat* )
132
CvBoostTree::scale( double _scale )
134
CvDTreeNode* node = root;
136
// traverse the tree and scale all the node values
142
node->value *= _scale;
148
for( parent = node->parent; parent && parent->right == node;
149
node = parent, parent = parent->parent )
155
node = parent->right;
161
CvBoostTree::try_split_node( CvDTreeNode* node )
163
CvDTree::try_split_node( node );
167
// if the node has not been split,
168
// store the responses for the corresponding training samples
169
double* weak_eval = ensemble->get_weak_response()->data.db;
170
cv::AutoBuffer<int> inn_buf(node->sample_count);
171
const int* labels = data->get_cv_labels( node, (int*)inn_buf );
172
int i, count = node->sample_count;
173
double value = node->value;
175
for( i = 0; i < count; i++ )
176
weak_eval[labels[i]] = value;
182
CvBoostTree::calc_node_dir( CvDTreeNode* node )
184
char* dir = (char*)data->direction->data.ptr;
185
const double* weights = ensemble->get_subtree_weights()->data.db;
186
int i, n = node->sample_count, vi = node->split->var_idx;
189
assert( !node->split->inversed );
191
if( data->get_var_type(vi) >= 0 ) // split on categorical var
193
cv::AutoBuffer<int> inn_buf(n);
194
const int* cat_labels = data->get_cat_var_data( node, vi, (int*)inn_buf );
195
const int* subset = node->split->subset;
196
double sum = 0, sum_abs = 0;
198
for( i = 0; i < n; i++ )
200
int idx = ((cat_labels[i] == 65535) && data->is_buf_16u) ? -1 : cat_labels[i];
201
double w = weights[i];
202
int d = idx >= 0 ? CV_DTREE_CAT_DIR(idx,subset) : 0;
203
sum += d*w; sum_abs += (d & 1)*w;
207
R = (sum_abs + sum) * 0.5;
208
L = (sum_abs - sum) * 0.5;
210
else // split on ordered var
212
cv::AutoBuffer<uchar> inn_buf(2*n*sizeof(int)+n*sizeof(float));
213
float* values_buf = (float*)(uchar*)inn_buf;
214
int* sorted_indices_buf = (int*)(values_buf + n);
215
int* sample_indices_buf = sorted_indices_buf + n;
216
const float* values = 0;
217
const int* sorted_indices = 0;
218
data->get_ord_var_data( node, vi, values_buf, sorted_indices_buf, &values, &sorted_indices, sample_indices_buf );
219
int split_point = node->split->ord.split_point;
220
int n1 = node->get_num_valid(vi);
222
assert( 0 <= split_point && split_point < n1-1 );
225
for( i = 0; i <= split_point; i++ )
227
int idx = sorted_indices[i];
228
double w = weights[idx];
235
int idx = sorted_indices[i];
236
double w = weights[idx];
242
dir[sorted_indices[i]] = (char)0;
245
node->maxlr = MAX( L, R );
246
return node->split->quality/(L + R);
251
CvBoostTree::find_split_ord_class( CvDTreeNode* node, int vi, float init_quality,
252
CvDTreeSplit* _split, uchar* _ext_buf )
254
const float epsilon = FLT_EPSILON*2;
256
const double* weights = ensemble->get_subtree_weights()->data.db;
257
int n = node->sample_count;
258
int n1 = node->get_num_valid(vi);
260
cv::AutoBuffer<uchar> inn_buf;
262
inn_buf.allocate(n*(3*sizeof(int)+sizeof(float)));
263
uchar* ext_buf = _ext_buf ? _ext_buf : (uchar*)inn_buf;
264
float* values_buf = (float*)ext_buf;
265
int* sorted_indices_buf = (int*)(values_buf + n);
266
int* sample_indices_buf = sorted_indices_buf + n;
267
const float* values = 0;
268
const int* sorted_indices = 0;
269
data->get_ord_var_data( node, vi, values_buf, sorted_indices_buf, &values, &sorted_indices, sample_indices_buf );
270
int* responses_buf = sorted_indices_buf + n;
271
const int* responses = data->get_class_labels( node, responses_buf );
272
const double* rcw0 = weights + n;
273
double lcw[2] = {0,0}, rcw[2];
275
double best_val = init_quality;
276
int boost_type = ensemble->get_params().boost_type;
277
int split_criteria = ensemble->get_params().split_criteria;
279
rcw[0] = rcw0[0]; rcw[1] = rcw0[1];
280
for( i = n1; i < n; i++ )
282
int idx = sorted_indices[i];
283
double w = weights[idx];
284
rcw[responses[idx]] -= w;
287
if( split_criteria != CvBoost::GINI && split_criteria != CvBoost::MISCLASS )
288
split_criteria = boost_type == CvBoost::DISCRETE ? CvBoost::MISCLASS : CvBoost::GINI;
290
if( split_criteria == CvBoost::GINI )
292
double L = 0, R = rcw[0] + rcw[1];
293
double lsum2 = 0, rsum2 = rcw[0]*rcw[0] + rcw[1]*rcw[1];
295
for( i = 0; i < n1 - 1; i++ )
297
int idx = sorted_indices[i];
298
double w = weights[idx], w2 = w*w;
300
idx = responses[idx];
302
lv = lcw[idx]; rv = rcw[idx];
303
lsum2 += 2*lv*w + w2;
304
rsum2 -= 2*rv*w - w2;
305
lcw[idx] = lv + w; rcw[idx] = rv - w;
307
if( values[i] + epsilon < values[i+1] )
309
double val = (lsum2*R + rsum2*L)/(L*R);
320
for( i = 0; i < n1 - 1; i++ )
322
int idx = sorted_indices[i];
323
double w = weights[idx];
324
idx = responses[idx];
328
if( values[i] + epsilon < values[i+1] )
330
double val = lcw[0] + rcw[1], val2 = lcw[1] + rcw[0];
331
val = MAX(val, val2);
341
CvDTreeSplit* split = 0;
344
split = _split ? _split : data->new_split_ord( 0, 0.0f, 0, 0, 0.0f );
346
split->ord.c = (values[best_i] + values[best_i+1])*0.5f;
347
split->ord.split_point = best_i;
349
split->quality = (float)best_val;
358
bool operator()(T* a, T* b) const { return *a < *b; }
362
CvBoostTree::find_split_cat_class( CvDTreeNode* node, int vi, float init_quality, CvDTreeSplit* _split, uchar* _ext_buf )
364
int ci = data->get_var_type(vi);
365
int n = node->sample_count;
366
int mi = data->cat_count->data.i[ci];
368
int base_size = (2*mi+3)*sizeof(double) + mi*sizeof(double*);
369
cv::AutoBuffer<uchar> inn_buf((2*mi+3)*sizeof(double) + mi*sizeof(double*));
371
inn_buf.allocate( base_size + 2*n*sizeof(int) );
372
uchar* base_buf = (uchar*)inn_buf;
373
uchar* ext_buf = _ext_buf ? _ext_buf : base_buf + base_size;
375
int* cat_labels_buf = (int*)ext_buf;
376
const int* cat_labels = data->get_cat_var_data(node, vi, cat_labels_buf);
377
int* responses_buf = cat_labels_buf + n;
378
const int* responses = data->get_class_labels(node, responses_buf);
379
double lcw[2]={0,0}, rcw[2]={0,0};
381
double* cjk = (double*)cv::alignPtr(base_buf,sizeof(double))+2;
382
const double* weights = ensemble->get_subtree_weights()->data.db;
383
double** dbl_ptr = (double**)(cjk + 2*mi);
386
double best_val = init_quality;
387
int best_subset = -1, subset_i;
388
int boost_type = ensemble->get_params().boost_type;
389
int split_criteria = ensemble->get_params().split_criteria;
391
// init array of counters:
392
// c_{jk} - number of samples that have vi-th input variable = j and response = k.
393
for( j = -1; j < mi; j++ )
394
cjk[j*2] = cjk[j*2+1] = 0;
396
for( i = 0; i < n; i++ )
398
double w = weights[i];
399
j = ((cat_labels[i] == 65535) && data->is_buf_16u) ? -1 : cat_labels[i];
404
for( j = 0; j < mi; j++ )
407
rcw[1] += cjk[j*2+1];
408
dbl_ptr[j] = cjk + j*2 + 1;
413
if( split_criteria != CvBoost::GINI && split_criteria != CvBoost::MISCLASS )
414
split_criteria = boost_type == CvBoost::DISCRETE ? CvBoost::MISCLASS : CvBoost::GINI;
416
// sort rows of c_jk by increasing c_j,1
417
// (i.e. by the weight of samples in j-th category that belong to class 1)
418
std::sort(dbl_ptr, dbl_ptr + mi, LessThanPtr<double>());
420
for( subset_i = 0; subset_i < mi-1; subset_i++ )
422
idx = (int)(dbl_ptr[subset_i] - cjk)/2;
423
const double* crow = cjk + idx*2;
424
double w0 = crow[0], w1 = crow[1];
425
double weight = w0 + w1;
427
if( weight < FLT_EPSILON )
430
lcw[0] += w0; rcw[0] -= w0;
431
lcw[1] += w1; rcw[1] -= w1;
433
if( split_criteria == CvBoost::GINI )
435
double lsum2 = lcw[0]*lcw[0] + lcw[1]*lcw[1];
436
double rsum2 = rcw[0]*rcw[0] + rcw[1]*rcw[1];
441
if( L > FLT_EPSILON && R > FLT_EPSILON )
443
double val = (lsum2*R + rsum2*L)/(L*R);
447
best_subset = subset_i;
453
double val = lcw[0] + rcw[1];
454
double val2 = lcw[1] + rcw[0];
456
val = MAX(val, val2);
460
best_subset = subset_i;
465
CvDTreeSplit* split = 0;
466
if( best_subset >= 0 )
468
split = _split ? _split : data->new_split_cat( 0, -1.0f);
470
split->quality = (float)best_val;
471
memset( split->subset, 0, (data->max_c_count + 31)/32 * sizeof(int));
472
for( i = 0; i <= best_subset; i++ )
474
idx = (int)(dbl_ptr[i] - cjk) >> 1;
475
split->subset[idx >> 5] |= 1 << (idx & 31);
483
CvBoostTree::find_split_ord_reg( CvDTreeNode* node, int vi, float init_quality, CvDTreeSplit* _split, uchar* _ext_buf )
485
const float epsilon = FLT_EPSILON*2;
486
const double* weights = ensemble->get_subtree_weights()->data.db;
487
int n = node->sample_count;
488
int n1 = node->get_num_valid(vi);
490
cv::AutoBuffer<uchar> inn_buf;
492
inn_buf.allocate(2*n*(sizeof(int)+sizeof(float)));
493
uchar* ext_buf = _ext_buf ? _ext_buf : (uchar*)inn_buf;
495
float* values_buf = (float*)ext_buf;
496
int* indices_buf = (int*)(values_buf + n);
497
int* sample_indices_buf = indices_buf + n;
498
const float* values = 0;
499
const int* indices = 0;
500
data->get_ord_var_data( node, vi, values_buf, indices_buf, &values, &indices, sample_indices_buf );
501
float* responses_buf = (float*)(indices_buf + n);
502
const float* responses = data->get_ord_responses( node, responses_buf, sample_indices_buf );
505
double L = 0, R = weights[n];
506
double best_val = init_quality, lsum = 0, rsum = node->value*R;
508
// compensate for missing values
509
for( i = n1; i < n; i++ )
511
int idx = indices[i];
512
double w = weights[idx];
513
rsum -= responses[idx]*w;
517
// find the optimal split
518
for( i = 0; i < n1 - 1; i++ )
520
int idx = indices[i];
521
double w = weights[idx];
522
double t = responses[idx]*w;
524
lsum += t; rsum -= t;
526
if( values[i] + epsilon < values[i+1] )
528
double val = (lsum*lsum*R + rsum*rsum*L)/(L*R);
537
CvDTreeSplit* split = 0;
540
split = _split ? _split : data->new_split_ord( 0, 0.0f, 0, 0, 0.0f );
542
split->ord.c = (values[best_i] + values[best_i+1])*0.5f;
543
split->ord.split_point = best_i;
545
split->quality = (float)best_val;
552
CvBoostTree::find_split_cat_reg( CvDTreeNode* node, int vi, float init_quality, CvDTreeSplit* _split, uchar* _ext_buf )
554
const double* weights = ensemble->get_subtree_weights()->data.db;
555
int ci = data->get_var_type(vi);
556
int n = node->sample_count;
557
int mi = data->cat_count->data.i[ci];
558
int base_size = (2*mi+3)*sizeof(double) + mi*sizeof(double*);
559
cv::AutoBuffer<uchar> inn_buf(base_size);
561
inn_buf.allocate(base_size + n*(2*sizeof(int) + sizeof(float)));
562
uchar* base_buf = (uchar*)inn_buf;
563
uchar* ext_buf = _ext_buf ? _ext_buf : base_buf + base_size;
565
int* cat_labels_buf = (int*)ext_buf;
566
const int* cat_labels = data->get_cat_var_data(node, vi, cat_labels_buf);
567
float* responses_buf = (float*)(cat_labels_buf + n);
568
int* sample_indices_buf = (int*)(responses_buf + n);
569
const float* responses = data->get_ord_responses(node, responses_buf, sample_indices_buf);
571
double* sum = (double*)cv::alignPtr(base_buf,sizeof(double)) + 1;
572
double* counts = sum + mi + 1;
573
double** sum_ptr = (double**)(counts + mi);
574
double L = 0, R = 0, best_val = init_quality, lsum = 0, rsum = 0;
575
int i, best_subset = -1, subset_i;
577
for( i = -1; i < mi; i++ )
578
sum[i] = counts[i] = 0;
580
// calculate sum response and weight of each category of the input var
581
for( i = 0; i < n; i++ )
583
int idx = ((cat_labels[i] == 65535) && data->is_buf_16u) ? -1 : cat_labels[i];
584
double w = weights[i];
585
double s = sum[idx] + responses[i]*w;
586
double nc = counts[idx] + w;
591
// calculate average response in each category
592
for( i = 0; i < mi; i++ )
596
sum[i] = fabs(counts[i]) > DBL_EPSILON ? sum[i]/counts[i] : 0;
597
sum_ptr[i] = sum + i;
600
std::sort(sum_ptr, sum_ptr + mi, LessThanPtr<double>());
602
// revert back to unnormalized sums
603
// (there should be a very little loss in accuracy)
604
for( i = 0; i < mi; i++ )
607
for( subset_i = 0; subset_i < mi-1; subset_i++ )
609
int idx = (int)(sum_ptr[subset_i] - sum);
610
double ni = counts[idx];
612
if( ni > FLT_EPSILON )
618
if( L > FLT_EPSILON && R > FLT_EPSILON )
620
double val = (lsum*lsum*R + rsum*rsum*L)/(L*R);
624
best_subset = subset_i;
630
CvDTreeSplit* split = 0;
631
if( best_subset >= 0 )
633
split = _split ? _split : data->new_split_cat( 0, -1.0f);
635
split->quality = (float)best_val;
636
memset( split->subset, 0, (data->max_c_count + 31)/32 * sizeof(int));
637
for( i = 0; i <= best_subset; i++ )
639
int idx = (int)(sum_ptr[i] - sum);
640
split->subset[idx >> 5] |= 1 << (idx & 31);
648
CvBoostTree::find_surrogate_split_ord( CvDTreeNode* node, int vi, uchar* _ext_buf )
650
const float epsilon = FLT_EPSILON*2;
651
int n = node->sample_count;
652
cv::AutoBuffer<uchar> inn_buf;
654
inn_buf.allocate(n*(2*sizeof(int)+sizeof(float)));
655
uchar* ext_buf = _ext_buf ? _ext_buf : (uchar*)inn_buf;
656
float* values_buf = (float*)ext_buf;
657
int* indices_buf = (int*)(values_buf + n);
658
int* sample_indices_buf = indices_buf + n;
659
const float* values = 0;
660
const int* indices = 0;
661
data->get_ord_var_data( node, vi, values_buf, indices_buf, &values, &indices, sample_indices_buf );
663
const double* weights = ensemble->get_subtree_weights()->data.db;
664
const char* dir = (char*)data->direction->data.ptr;
665
int n1 = node->get_num_valid(vi);
666
// LL - number of samples that both the primary and the surrogate splits send to the left
667
// LR - ... primary split sends to the left and the surrogate split sends to the right
668
// RL - ... primary split sends to the right and the surrogate split sends to the left
669
// RR - ... both send to the right
670
int i, best_i = -1, best_inversed = 0;
672
double LL = 0, RL = 0, LR, RR;
673
double worst_val = node->maxlr;
674
double sum = 0, sum_abs = 0;
675
best_val = worst_val;
677
for( i = 0; i < n1; i++ )
679
int idx = indices[i];
680
double w = weights[idx];
682
sum += d*w; sum_abs += (d & 1)*w;
685
// sum_abs = R + L; sum = R - L
686
RR = (sum_abs + sum)*0.5;
687
LR = (sum_abs - sum)*0.5;
689
// initially all the samples are sent to the right by the surrogate split,
690
// LR of them are sent to the left by primary split, and RR - to the right.
691
// now iteratively compute LL, LR, RL and RR for every possible surrogate split value.
692
for( i = 0; i < n1 - 1; i++ )
694
int idx = indices[i];
695
double w = weights[idx];
701
if( LL + RR > best_val && values[i] + epsilon < values[i+1] )
704
best_i = i; best_inversed = 0;
710
if( RL + LR > best_val && values[i] + epsilon < values[i+1] )
713
best_i = i; best_inversed = 1;
718
return best_i >= 0 && best_val > node->maxlr ? data->new_split_ord( vi,
719
(values[best_i] + values[best_i+1])*0.5f, best_i,
720
best_inversed, (float)best_val ) : 0;
725
CvBoostTree::find_surrogate_split_cat( CvDTreeNode* node, int vi, uchar* _ext_buf )
727
const char* dir = (char*)data->direction->data.ptr;
728
const double* weights = ensemble->get_subtree_weights()->data.db;
729
int n = node->sample_count;
730
int i, mi = data->cat_count->data.i[data->get_var_type(vi)];
732
int base_size = (2*mi+3)*sizeof(double);
733
cv::AutoBuffer<uchar> inn_buf(base_size);
735
inn_buf.allocate(base_size + n*sizeof(int));
736
uchar* ext_buf = _ext_buf ? _ext_buf : (uchar*)inn_buf;
737
int* cat_labels_buf = (int*)ext_buf;
738
const int* cat_labels = data->get_cat_var_data(node, vi, cat_labels_buf);
740
// LL - number of samples that both the primary and the surrogate splits send to the left
741
// LR - ... primary split sends to the left and the surrogate split sends to the right
742
// RL - ... primary split sends to the right and the surrogate split sends to the left
743
// RR - ... both send to the right
744
CvDTreeSplit* split = data->new_split_cat( vi, 0 );
746
double* lc = (double*)cv::alignPtr(cat_labels_buf + n, sizeof(double)) + 1;
747
double* rc = lc + mi + 1;
749
for( i = -1; i < mi; i++ )
752
// 1. for each category calculate the weight of samples
753
// sent to the left (lc) and to the right (rc) by the primary split
754
for( i = 0; i < n; i++ )
756
int idx = ((cat_labels[i] == 65535) && data->is_buf_16u) ? -1 : cat_labels[i];
757
double w = weights[i];
759
double sum = lc[idx] + d*w;
760
double sum_abs = rc[idx] + (d & 1)*w;
761
lc[idx] = sum; rc[idx] = sum_abs;
764
for( i = 0; i < mi; i++ )
767
double sum_abs = rc[i];
768
lc[i] = (sum_abs - sum) * 0.5;
769
rc[i] = (sum_abs + sum) * 0.5;
772
// 2. now form the split.
773
// in each category send all the samples to the same direction as majority
774
for( i = 0; i < mi; i++ )
776
double lval = lc[i], rval = rc[i];
779
split->subset[i >> 5] |= 1 << (i & 31);
786
split->quality = (float)best_val;
787
if( split->quality <= node->maxlr )
788
cvSetRemoveByPtr( data->split_heap, split ), split = 0;
795
CvBoostTree::calc_node_value( CvDTreeNode* node )
797
int i, n = node->sample_count;
798
const double* weights = ensemble->get_weights()->data.db;
799
cv::AutoBuffer<uchar> inn_buf(n*(sizeof(int) + ( data->is_classifier ? sizeof(int) : sizeof(int) + sizeof(float))));
800
int* labels_buf = (int*)(uchar*)inn_buf;
801
const int* labels = data->get_cv_labels(node, labels_buf);
802
double* subtree_weights = ensemble->get_subtree_weights()->data.db;
803
double rcw[2] = {0,0};
804
int boost_type = ensemble->get_params().boost_type;
806
if( data->is_classifier )
808
int* _responses_buf = labels_buf + n;
809
const int* _responses = data->get_class_labels(node, _responses_buf);
810
int m = data->get_num_classes();
811
int* cls_count = data->counts->data.i;
812
for( int k = 0; k < m; k++ )
815
for( i = 0; i < n; i++ )
818
double w = weights[idx];
819
int r = _responses[i];
822
subtree_weights[i] = w;
825
node->class_idx = rcw[1] > rcw[0];
827
if( boost_type == CvBoost::DISCRETE )
829
// ignore cat_map for responses, and use {-1,1},
830
// as the whole ensemble response is computes as sign(sum_i(weak_response_i)
831
node->value = node->class_idx*2 - 1;
835
double p = rcw[1]/(rcw[0] + rcw[1]);
836
assert( boost_type == CvBoost::REAL );
838
// store log-ratio of the probability
839
node->value = 0.5*log_ratio(p);
844
// in case of regression tree:
845
// * node value is 1/n*sum_i(Y_i), where Y_i is i-th response,
846
// n is the number of samples in the node.
847
// * node risk is the sum of squared errors: sum_i((Y_i - <node_value>)^2)
848
double sum = 0, sum2 = 0, iw;
849
float* values_buf = (float*)(labels_buf + n);
850
int* sample_indices_buf = (int*)(values_buf + n);
851
const float* values = data->get_ord_responses(node, values_buf, sample_indices_buf);
853
for( i = 0; i < n; i++ )
856
double w = weights[idx]/*priors[values[i] > 0]*/;
857
double t = values[i];
859
subtree_weights[i] = w;
865
node->value = sum*iw;
866
node->node_risk = sum2 - (sum*iw)*sum;
868
// renormalize the risk, as in try_split_node the unweighted formula
869
// sqrt(risk)/n is used, rather than sqrt(risk)/sum(weights_i)
870
node->node_risk *= n*iw*n*iw;
873
// store summary weights
874
subtree_weights[n] = rcw[0];
875
subtree_weights[n+1] = rcw[1];
879
void CvBoostTree::read( CvFileStorage* fs, CvFileNode* fnode, CvBoost* _ensemble, CvDTreeTrainData* _data )
881
CvDTree::read( fs, fnode, _data );
882
ensemble = _ensemble;
885
void CvBoostTree::read( CvFileStorage*, CvFileNode* )
890
void CvBoostTree::read( CvFileStorage* _fs, CvFileNode* _node,
891
CvDTreeTrainData* _data )
893
CvDTree::read( _fs, _node, _data );
897
/////////////////////////////////// CvBoost /////////////////////////////////////
903
default_model_name = "my_boost_tree";
905
active_vars = active_vars_abs = orig_response = sum_response = weak_eval =
906
subsample_mask = weights = subtree_weights = 0;
907
have_active_cat_vars = have_subsample = false;
913
void CvBoost::prune( CvSlice slice )
915
if( weak && weak->total > 0 )
918
int i, count = cvSliceLength( slice, weak );
920
cvStartReadSeq( weak, &reader );
921
cvSetSeqReaderPos( &reader, slice.start_index );
923
for( i = 0; i < count; i++ )
926
CV_READ_SEQ_ELEM( w, reader );
930
cvSeqRemoveSlice( weak, slice );
935
void CvBoost::clear()
939
prune( CV_WHOLE_SEQ );
940
cvReleaseMemStorage( &weak->storage );
946
cvReleaseMat( &active_vars );
947
cvReleaseMat( &active_vars_abs );
948
cvReleaseMat( &orig_response );
949
cvReleaseMat( &sum_response );
950
cvReleaseMat( &weak_eval );
951
cvReleaseMat( &subsample_mask );
952
cvReleaseMat( &weights );
953
cvReleaseMat( &subtree_weights );
955
have_subsample = false;
965
CvBoost::CvBoost( const CvMat* _train_data, int _tflag,
966
const CvMat* _responses, const CvMat* _var_idx,
967
const CvMat* _sample_idx, const CvMat* _var_type,
968
const CvMat* _missing_mask, CvBoostParams _params )
972
default_model_name = "my_boost_tree";
974
active_vars = active_vars_abs = orig_response = sum_response = weak_eval =
975
subsample_mask = weights = subtree_weights = 0;
977
train( _train_data, _tflag, _responses, _var_idx, _sample_idx,
978
_var_type, _missing_mask, _params );
983
CvBoost::set_params( const CvBoostParams& _params )
987
CV_FUNCNAME( "CvBoost::set_params" );
992
if( params.boost_type != DISCRETE && params.boost_type != REAL &&
993
params.boost_type != LOGIT && params.boost_type != GENTLE )
994
CV_ERROR( CV_StsBadArg, "Unknown/unsupported boosting type" );
996
params.weak_count = MAX( params.weak_count, 1 );
997
params.weight_trim_rate = MAX( params.weight_trim_rate, 0. );
998
params.weight_trim_rate = MIN( params.weight_trim_rate, 1. );
999
if( params.weight_trim_rate < FLT_EPSILON )
1000
params.weight_trim_rate = 1.f;
1002
if( params.boost_type == DISCRETE &&
1003
params.split_criteria != GINI && params.split_criteria != MISCLASS )
1004
params.split_criteria = MISCLASS;
1005
if( params.boost_type == REAL &&
1006
params.split_criteria != GINI && params.split_criteria != MISCLASS )
1007
params.split_criteria = GINI;
1008
if( (params.boost_type == LOGIT || params.boost_type == GENTLE) &&
1009
params.split_criteria != SQERR )
1010
params.split_criteria = SQERR;
1021
CvBoost::train( const CvMat* _train_data, int _tflag,
1022
const CvMat* _responses, const CvMat* _var_idx,
1023
const CvMat* _sample_idx, const CvMat* _var_type,
1024
const CvMat* _missing_mask,
1025
CvBoostParams _params, bool _update )
1028
CvMemStorage* storage = 0;
1030
CV_FUNCNAME( "CvBoost::train" );
1036
set_params( _params );
1038
cvReleaseMat( &active_vars );
1039
cvReleaseMat( &active_vars_abs );
1041
if( !_update || !data )
1044
data = new CvDTreeTrainData( _train_data, _tflag, _responses, _var_idx,
1045
_sample_idx, _var_type, _missing_mask, _params, true, true );
1047
if( data->get_num_classes() != 2 )
1048
CV_ERROR( CV_StsNotImplemented,
1049
"Boosted trees can only be used for 2-class classification." );
1050
CV_CALL( storage = cvCreateMemStorage() );
1051
weak = cvCreateSeq( 0, sizeof(CvSeq), sizeof(CvBoostTree*), storage );
1056
data->set_data( _train_data, _tflag, _responses, _var_idx,
1057
_sample_idx, _var_type, _missing_mask, _params, true, true, true );
1060
if ( (_params.boost_type == LOGIT) || (_params.boost_type == GENTLE) )
1061
data->do_responses_copy();
1063
update_weights( 0 );
1065
for( i = 0; i < params.weak_count; i++ )
1067
CvBoostTree* tree = new CvBoostTree;
1068
if( !tree->train( data, subsample_mask, this ) )
1073
//cvCheckArr( get_weak_response());
1074
cvSeqPush( weak, &tree );
1075
update_weights( tree );
1077
if( cvCountNonZero(subsample_mask) == 0 )
1083
get_active_vars(); // recompute active_vars* maps and condensed_idx's in the splits.
1084
data->is_classifier = true;
1085
data->free_train_data();
1096
bool CvBoost::train( CvMLData* _data,
1097
CvBoostParams _params,
1100
bool result = false;
1102
CV_FUNCNAME( "CvBoost::train" );
1106
const CvMat* values = _data->get_values();
1107
const CvMat* response = _data->get_responses();
1108
const CvMat* missing = _data->get_missing();
1109
const CvMat* var_types = _data->get_var_types();
1110
const CvMat* train_sidx = _data->get_train_sample_idx();
1111
const CvMat* var_idx = _data->get_var_idx();
1113
CV_CALL( result = train( values, CV_ROW_SAMPLE, response, var_idx,
1114
train_sidx, var_types, missing, _params, update ) );
1121
void CvBoost::initialize_weights(double (&p)[2])
1128
CvBoost::update_weights( CvBoostTree* tree )
1130
CV_FUNCNAME( "CvBoost::update_weights" );
1134
int i, n = data->sample_count;
1138
int *sample_idx_buf;
1139
const int* sample_idx = 0;
1140
cv::AutoBuffer<uchar> inn_buf;
1141
size_t _buf_size = (params.boost_type == LOGIT) || (params.boost_type == GENTLE) ? (size_t)(data->sample_count)*sizeof(int) : 0;
1143
_buf_size += n*sizeof(int);
1146
if( have_subsample )
1147
_buf_size += data->get_length_subbuf()*(sizeof(float)+sizeof(uchar));
1149
inn_buf.allocate(_buf_size);
1150
uchar* cur_buf_pos = (uchar*)inn_buf;
1152
if ( (params.boost_type == LOGIT) || (params.boost_type == GENTLE) )
1154
step = CV_IS_MAT_CONT(data->responses_copy->type) ?
1155
1 : data->responses_copy->step / CV_ELEM_SIZE(data->responses_copy->type);
1156
fdata = data->responses_copy->data.fl;
1157
sample_idx_buf = (int*)cur_buf_pos;
1158
cur_buf_pos = (uchar*)(sample_idx_buf + data->sample_count);
1159
sample_idx = data->get_sample_indices( data->data_root, sample_idx_buf );
1161
CvMat* dtree_data_buf = data->buf;
1162
size_t length_buf_row = data->get_length_subbuf();
1163
if( !tree ) // before training the first tree, initialize weights and other parameters
1165
int* class_labels_buf = (int*)cur_buf_pos;
1166
cur_buf_pos = (uchar*)(class_labels_buf + n);
1167
const int* class_labels = data->get_class_labels(data->data_root, class_labels_buf);
1168
// in case of logitboost and gentle adaboost each weak tree is a regression tree,
1169
// so we need to convert class labels to floating-point values
1172
double p[2] = { 1., 1. };
1173
initialize_weights(p);
1175
cvReleaseMat( &orig_response );
1176
cvReleaseMat( &sum_response );
1177
cvReleaseMat( &weak_eval );
1178
cvReleaseMat( &subsample_mask );
1179
cvReleaseMat( &weights );
1180
cvReleaseMat( &subtree_weights );
1182
CV_CALL( orig_response = cvCreateMat( 1, n, CV_32S ));
1183
CV_CALL( weak_eval = cvCreateMat( 1, n, CV_64F ));
1184
CV_CALL( subsample_mask = cvCreateMat( 1, n, CV_8U ));
1185
CV_CALL( weights = cvCreateMat( 1, n, CV_64F ));
1186
CV_CALL( subtree_weights = cvCreateMat( 1, n + 2, CV_64F ));
1188
if( data->have_priors )
1190
// compute weight scale for each class from their prior probabilities
1192
for( i = 0; i < n; i++ )
1193
c1 += class_labels[i];
1194
p[0] = data->priors->data.db[0]*(c1 < n ? 1./(n - c1) : 0.);
1195
p[1] = data->priors->data.db[1]*(c1 > 0 ? 1./c1 : 0.);
1196
p[0] /= p[0] + p[1];
1200
if (data->is_buf_16u)
1202
unsigned short* labels = (unsigned short*)(dtree_data_buf->data.s + data->data_root->buf_idx*length_buf_row +
1203
data->data_root->offset + (size_t)(data->work_var_count-1)*data->sample_count);
1204
for( i = 0; i < n; i++ )
1206
// save original categorical responses {0,1}, convert them to {-1,1}
1207
orig_response->data.i[i] = class_labels[i]*2 - 1;
1208
// make all the samples active at start.
1209
// later, in trim_weights() deactivate/reactive again some, if need
1210
subsample_mask->data.ptr[i] = (uchar)1;
1211
// make all the initial weights the same.
1212
weights->data.db[i] = w0*p[class_labels[i]];
1213
// set the labels to find (from within weak tree learning proc)
1214
// the particular sample weight, and where to store the response.
1215
labels[i] = (unsigned short)i;
1220
int* labels = dtree_data_buf->data.i + data->data_root->buf_idx*length_buf_row +
1221
data->data_root->offset + (size_t)(data->work_var_count-1)*data->sample_count;
1223
for( i = 0; i < n; i++ )
1225
// save original categorical responses {0,1}, convert them to {-1,1}
1226
orig_response->data.i[i] = class_labels[i]*2 - 1;
1227
// make all the samples active at start.
1228
// later, in trim_weights() deactivate/reactive again some, if need
1229
subsample_mask->data.ptr[i] = (uchar)1;
1230
// make all the initial weights the same.
1231
weights->data.db[i] = w0*p[class_labels[i]];
1232
// set the labels to find (from within weak tree learning proc)
1233
// the particular sample weight, and where to store the response.
1238
if( params.boost_type == LOGIT )
1240
CV_CALL( sum_response = cvCreateMat( 1, n, CV_64F ));
1242
for( i = 0; i < n; i++ )
1244
sum_response->data.db[i] = 0;
1245
fdata[sample_idx[i]*step] = orig_response->data.i[i] > 0 ? 2.f : -2.f;
1248
// in case of logitboost each weak tree is a regression tree.
1249
// the target function values are recalculated for each of the trees
1250
data->is_classifier = false;
1252
else if( params.boost_type == GENTLE )
1254
for( i = 0; i < n; i++ )
1255
fdata[sample_idx[i]*step] = (float)orig_response->data.i[i];
1257
data->is_classifier = false;
1262
// at this moment, for all the samples that participated in the training of the most
1263
// recent weak classifier we know the responses. For other samples we need to compute them
1264
if( have_subsample )
1266
float* values = (float*)cur_buf_pos;
1267
cur_buf_pos = (uchar*)(values + data->get_length_subbuf());
1268
uchar* missing = cur_buf_pos;
1269
cur_buf_pos = missing + data->get_length_subbuf() * (size_t)CV_ELEM_SIZE(data->buf->type);
1271
CvMat _sample, _mask;
1273
// invert the subsample mask
1274
cvXorS( subsample_mask, cvScalar(1.), subsample_mask );
1275
data->get_vectors( subsample_mask, values, missing, 0 );
1277
_sample = cvMat( 1, data->var_count, CV_32F );
1278
_mask = cvMat( 1, data->var_count, CV_8U );
1280
// run tree through all the non-processed samples
1281
for( i = 0; i < n; i++ )
1282
if( subsample_mask->data.ptr[i] )
1284
_sample.data.fl = values;
1285
_mask.data.ptr = missing;
1286
values += _sample.cols;
1287
missing += _mask.cols;
1288
weak_eval->data.db[i] = tree->predict( &_sample, &_mask, true )->value;
1292
// now update weights and other parameters for each type of boosting
1293
if( params.boost_type == DISCRETE )
1295
// Discrete AdaBoost:
1296
// weak_eval[i] (=f(x_i)) is in {-1,1}
1297
// err = sum(w_i*(f(x_i) != y_i))/sum(w_i)
1298
// C = log((1-err)/err)
1299
// w_i *= exp(C*(f(x_i) != y_i))
1302
double scale[] = { 1., 0. };
1304
for( i = 0; i < n; i++ )
1306
double w = weights->data.db[i];
1308
err += w*(weak_eval->data.db[i] != orig_response->data.i[i]);
1313
C = err = -log_ratio( err );
1314
scale[1] = exp(err);
1317
for( i = 0; i < n; i++ )
1319
double w = weights->data.db[i]*
1320
scale[weak_eval->data.db[i] != orig_response->data.i[i]];
1322
weights->data.db[i] = w;
1327
else if( params.boost_type == REAL )
1330
// weak_eval[i] = f(x_i) = 0.5*log(p(x_i)/(1-p(x_i))), p(x_i)=P(y=1|x_i)
1331
// w_i *= exp(-y_i*f(x_i))
1333
for( i = 0; i < n; i++ )
1334
weak_eval->data.db[i] *= -orig_response->data.i[i];
1336
cvExp( weak_eval, weak_eval );
1338
for( i = 0; i < n; i++ )
1340
double w = weights->data.db[i]*weak_eval->data.db[i];
1342
weights->data.db[i] = w;
1345
else if( params.boost_type == LOGIT )
1348
// weak_eval[i] = f(x_i) in [-z_max,z_max]
1349
// sum_response = F(x_i).
1350
// F(x_i) += 0.5*f(x_i)
1351
// p(x_i) = exp(F(x_i))/(exp(F(x_i)) + exp(-F(x_i))=1/(1+exp(-2*F(x_i)))
1352
// reuse weak_eval: weak_eval[i] <- p(x_i)
1353
// w_i = p(x_i)*1(1 - p(x_i))
1354
// z_i = ((y_i+1)/2 - p(x_i))/(p(x_i)*(1 - p(x_i)))
1355
// store z_i to the data->data_root as the new target responses
1357
const double lb_weight_thresh = FLT_EPSILON;
1358
const double lb_z_max = 10.;
1359
/*float* responses_buf = data->get_resp_float_buf();
1360
const float* responses = 0;
1361
data->get_ord_responses(data->data_root, responses_buf, &responses);*/
1363
/*if( weak->total == 7 )
1366
for( i = 0; i < n; i++ )
1368
double s = sum_response->data.db[i] + 0.5*weak_eval->data.db[i];
1369
sum_response->data.db[i] = s;
1370
weak_eval->data.db[i] = -2*s;
1373
cvExp( weak_eval, weak_eval );
1375
for( i = 0; i < n; i++ )
1377
double p = 1./(1. + weak_eval->data.db[i]);
1378
double w = p*(1 - p), z;
1379
w = MAX( w, lb_weight_thresh );
1380
weights->data.db[i] = w;
1382
if( orig_response->data.i[i] > 0 )
1385
fdata[sample_idx[i]*step] = (float)MIN(z, lb_z_max);
1390
fdata[sample_idx[i]*step] = (float)-MIN(z, lb_z_max);
1397
// weak_eval[i] = f(x_i) in [-1,1]
1398
// w_i *= exp(-y_i*f(x_i))
1399
assert( params.boost_type == GENTLE );
1401
for( i = 0; i < n; i++ )
1402
weak_eval->data.db[i] *= -orig_response->data.i[i];
1404
cvExp( weak_eval, weak_eval );
1406
for( i = 0; i < n; i++ )
1408
double w = weights->data.db[i] * weak_eval->data.db[i];
1409
weights->data.db[i] = w;
1415
// renormalize weights
1416
if( sumw > FLT_EPSILON )
1419
for( i = 0; i < n; ++i )
1420
weights->data.db[i] *= sumw;
1428
CvBoost::trim_weights()
1430
//CV_FUNCNAME( "CvBoost::trim_weights" );
1434
int i, count = data->sample_count, nz_count = 0;
1435
double sum, threshold;
1437
if( params.weight_trim_rate <= 0. || params.weight_trim_rate >= 1. )
1440
// use weak_eval as temporary buffer for sorted weights
1441
cvCopy( weights, weak_eval );
1443
std::sort(weak_eval->data.db, weak_eval->data.db + count);
1445
// as weight trimming occurs immediately after updating the weights,
1446
// where they are renormalized, we assume that the weight sum = 1.
1447
sum = 1. - params.weight_trim_rate;
1449
for( i = 0; i < count; i++ )
1451
double w = weak_eval->data.db[i];
1457
threshold = i < count ? weak_eval->data.db[i] : DBL_MAX;
1459
for( i = 0; i < count; i++ )
1461
double w = weights->data.db[i];
1462
int f = w >= threshold;
1463
subsample_mask->data.ptr[i] = (uchar)f;
1467
have_subsample = nz_count < count;
1474
CvBoost::get_active_vars( bool absolute_idx )
1480
CV_FUNCNAME( "CvBoost::get_active_vars" );
1485
CV_ERROR( CV_StsError, "The boosted tree ensemble has not been trained yet" );
1487
if( !active_vars || !active_vars_abs )
1490
int i, j, nactive_vars;
1492
const CvDTreeNode* node;
1494
assert(!active_vars && !active_vars_abs);
1495
mask = cvCreateMat( 1, data->var_count, CV_8U );
1496
inv_map = cvCreateMat( 1, data->var_count, CV_32S );
1498
cvSet( inv_map, cvScalar(-1) );
1500
// first pass: compute the mask of used variables
1501
cvStartReadSeq( weak, &reader );
1502
for( i = 0; i < weak->total; i++ )
1504
CV_READ_SEQ_ELEM(wtree, reader);
1506
node = wtree->get_root();
1507
assert( node != 0 );
1510
const CvDTreeNode* parent;
1513
CvDTreeSplit* split = node->split;
1514
for( ; split != 0; split = split->next )
1515
mask->data.ptr[split->var_idx] = 1;
1521
for( parent = node->parent; parent && parent->right == node;
1522
node = parent, parent = parent->parent )
1528
node = parent->right;
1532
nactive_vars = cvCountNonZero(mask);
1534
//if ( nactive_vars > 0 )
1536
active_vars = cvCreateMat( 1, nactive_vars, CV_32S );
1537
active_vars_abs = cvCreateMat( 1, nactive_vars, CV_32S );
1539
have_active_cat_vars = false;
1541
for( i = j = 0; i < data->var_count; i++ )
1543
if( mask->data.ptr[i] )
1545
active_vars->data.i[j] = i;
1546
active_vars_abs->data.i[j] = data->var_idx ? data->var_idx->data.i[i] : i;
1547
inv_map->data.i[i] = j;
1548
if( data->var_type->data.i[i] >= 0 )
1549
have_active_cat_vars = true;
1555
// second pass: now compute the condensed indices
1556
cvStartReadSeq( weak, &reader );
1557
for( i = 0; i < weak->total; i++ )
1559
CV_READ_SEQ_ELEM(wtree, reader);
1560
node = wtree->get_root();
1563
const CvDTreeNode* parent;
1566
CvDTreeSplit* split = node->split;
1567
for( ; split != 0; split = split->next )
1569
split->condensed_idx = inv_map->data.i[split->var_idx];
1570
assert( split->condensed_idx >= 0 );
1578
for( parent = node->parent; parent && parent->right == node;
1579
node = parent, parent = parent->parent )
1585
node = parent->right;
1591
result = absolute_idx ? active_vars_abs : active_vars;
1595
cvReleaseMat( &mask );
1596
cvReleaseMat( &inv_map );
1603
CvBoost::predict( const CvMat* _sample, const CvMat* _missing,
1604
CvMat* weak_responses, CvSlice slice,
1605
bool raw_mode, bool return_sum ) const
1607
float value = -FLT_MAX;
1612
const float* sample_data;
1615
CV_Error( CV_StsError, "The boosted tree ensemble has not been trained yet" );
1617
if( !CV_IS_MAT(_sample) || CV_MAT_TYPE(_sample->type) != CV_32FC1 ||
1618
(_sample->cols != 1 && _sample->rows != 1) ||
1619
(_sample->cols + _sample->rows - 1 != data->var_all && !raw_mode) ||
1620
(active_vars && _sample->cols + _sample->rows - 1 != active_vars->cols && raw_mode) )
1621
CV_Error( CV_StsBadArg,
1622
"the input sample must be 1d floating-point vector with the same "
1623
"number of elements as the total number of variables or "
1624
"as the number of variables used for training" );
1628
if( !CV_IS_MAT(_missing) || !CV_IS_MASK_ARR(_missing) ||
1629
!CV_ARE_SIZES_EQ(_missing, _sample) )
1630
CV_Error( CV_StsBadArg,
1631
"the missing data mask must be 8-bit vector of the same size as input sample" );
1634
int i, weak_count = cvSliceLength( slice, weak );
1635
if( weak_count >= weak->total )
1637
weak_count = weak->total;
1638
slice.start_index = 0;
1641
if( weak_responses )
1643
if( !CV_IS_MAT(weak_responses) ||
1644
CV_MAT_TYPE(weak_responses->type) != CV_32FC1 ||
1645
(weak_responses->cols != 1 && weak_responses->rows != 1) ||
1646
weak_responses->cols + weak_responses->rows - 1 != weak_count )
1647
CV_Error( CV_StsBadArg,
1648
"The output matrix of weak classifier responses must be valid "
1649
"floating-point vector of the same number of components as the length of input slice" );
1650
wstep = CV_IS_MAT_CONT(weak_responses->type) ? 1 : weak_responses->step/sizeof(float);
1653
int var_count = active_vars->cols;
1654
const int* vtype = data->var_type->data.i;
1655
const int* cmap = data->cat_map->data.i;
1656
const int* cofs = data->cat_ofs->data.i;
1658
cv::Mat sample = cv::cvarrToMat(_sample);
1661
missing = cv::cvarrToMat(_missing);
1663
// if need, preprocess the input vector
1666
int sstep, mstep = 0;
1667
const float* src_sample;
1668
const uchar* src_mask = 0;
1671
const int* vidx = active_vars->data.i;
1672
const int* vidx_abs = active_vars_abs->data.i;
1673
bool have_mask = _missing != 0;
1675
sample = cv::Mat(1, var_count, CV_32FC1);
1676
missing = cv::Mat(1, var_count, CV_8UC1);
1678
dst_sample = sample.ptr<float>();
1679
dst_mask = missing.ptr<uchar>();
1681
src_sample = _sample->data.fl;
1682
sstep = CV_IS_MAT_CONT(_sample->type) ? 1 : _sample->step/sizeof(src_sample[0]);
1686
src_mask = _missing->data.ptr;
1687
mstep = CV_IS_MAT_CONT(_missing->type) ? 1 : _missing->step;
1690
for( i = 0; i < var_count; i++ )
1692
int idx = vidx[i], idx_abs = vidx_abs[i];
1693
float val = src_sample[idx_abs*sstep];
1694
int ci = vtype[idx];
1695
uchar m = src_mask ? src_mask[idx_abs*mstep] : (uchar)0;
1699
int a = cofs[ci], b = (ci+1 >= data->cat_ofs->cols) ? data->cat_map->cols : cofs[ci+1],
1701
int ival = cvRound(val);
1702
if ( (ival != val) && (!m) )
1703
CV_Error( CV_StsBadArg,
1704
"one of input categorical variable is not an integer" );
1709
if( ival < cmap[c] )
1711
else if( ival > cmap[c] )
1717
if( c < 0 || ival != cmap[c] )
1724
val = (float)(c - cofs[ci]);
1728
dst_sample[i] = val;
1737
if( !CV_IS_MAT_CONT(_sample->type & (_missing ? _missing->type : -1)) )
1738
CV_Error( CV_StsBadArg, "In raw mode the input vectors must be continuous" );
1741
cvStartReadSeq( weak, &reader );
1742
cvSetSeqReaderPos( &reader, slice.start_index );
1744
sample_data = sample.ptr<float>();
1746
if( !have_active_cat_vars && missing.empty() && !weak_responses )
1748
for( i = 0; i < weak_count; i++ )
1751
const CvDTreeNode* node;
1752
CV_READ_SEQ_ELEM( wtree, reader );
1754
node = wtree->get_root();
1757
CvDTreeSplit* split = node->split;
1758
int vi = split->condensed_idx;
1759
float val = sample_data[vi];
1760
int dir = val <= split->ord.c ? -1 : 1;
1761
if( split->inversed )
1763
node = dir < 0 ? node->left : node->right;
1770
const int* avars = active_vars->data.i;
1771
const uchar* m = !missing.empty() ? missing.ptr<uchar>() : 0;
1773
// full-featured version
1774
for( i = 0; i < weak_count; i++ )
1777
const CvDTreeNode* node;
1778
CV_READ_SEQ_ELEM( wtree, reader );
1780
node = wtree->get_root();
1783
const CvDTreeSplit* split = node->split;
1785
for( ; !dir && split != 0; split = split->next )
1787
int vi = split->condensed_idx;
1788
int ci = vtype[avars[vi]];
1789
float val = sample_data[vi];
1792
if( ci < 0 ) // ordered
1793
dir = val <= split->ord.c ? -1 : 1;
1796
int c = cvRound(val);
1797
dir = CV_DTREE_CAT_DIR(c, split->subset);
1799
if( split->inversed )
1805
int diff = node->right->sample_count - node->left->sample_count;
1806
dir = diff < 0 ? -1 : 1;
1808
node = dir < 0 ? node->left : node->right;
1810
if( weak_responses )
1811
weak_responses->data.fl[i*wstep] = (float)node->value;
1820
int cls_idx = sum >= 0;
1822
value = (float)cls_idx;
1824
value = (float)cmap[cofs[vtype[data->var_count]] + cls_idx];
1830
float CvBoost::calc_error( CvMLData* _data, int type, std::vector<float> *resp )
1833
const CvMat* values = _data->get_values();
1834
const CvMat* response = _data->get_responses();
1835
const CvMat* missing = _data->get_missing();
1836
const CvMat* sample_idx = (type == CV_TEST_ERROR) ? _data->get_test_sample_idx() : _data->get_train_sample_idx();
1837
const CvMat* var_types = _data->get_var_types();
1838
int* sidx = sample_idx ? sample_idx->data.i : 0;
1839
int r_step = CV_IS_MAT_CONT(response->type) ?
1840
1 : response->step / CV_ELEM_SIZE(response->type);
1841
bool is_classifier = var_types->data.ptr[var_types->cols-1] == CV_VAR_CATEGORICAL;
1842
int sample_count = sample_idx ? sample_idx->cols : 0;
1843
sample_count = (type == CV_TRAIN_ERROR && sample_count == 0) ? values->rows : sample_count;
1844
float* pred_resp = 0;
1845
if( resp && (sample_count > 0) )
1847
resp->resize( sample_count );
1848
pred_resp = &((*resp)[0]);
1850
if ( is_classifier )
1852
for( int i = 0; i < sample_count; i++ )
1855
int si = sidx ? sidx[i] : i;
1856
cvGetRow( values, &sample, si );
1858
cvGetRow( missing, &miss, si );
1859
float r = (float)predict( &sample, missing ? &miss : 0 );
1862
int d = fabs((double)r - response->data.fl[si*r_step]) <= FLT_EPSILON ? 0 : 1;
1865
err = sample_count ? err / (float)sample_count * 100 : -FLT_MAX;
1869
for( int i = 0; i < sample_count; i++ )
1872
int si = sidx ? sidx[i] : i;
1873
cvGetRow( values, &sample, si );
1875
cvGetRow( missing, &miss, si );
1876
float r = (float)predict( &sample, missing ? &miss : 0 );
1879
float d = r - response->data.fl[si*r_step];
1882
err = sample_count ? err / (float)sample_count : -FLT_MAX;
1887
void CvBoost::write_params( CvFileStorage* fs ) const
1889
const char* boost_type_str =
1890
params.boost_type == DISCRETE ? "DiscreteAdaboost" :
1891
params.boost_type == REAL ? "RealAdaboost" :
1892
params.boost_type == LOGIT ? "LogitBoost" :
1893
params.boost_type == GENTLE ? "GentleAdaboost" : 0;
1895
const char* split_crit_str =
1896
params.split_criteria == DEFAULT ? "Default" :
1897
params.split_criteria == GINI ? "Gini" :
1898
params.boost_type == MISCLASS ? "Misclassification" :
1899
params.boost_type == SQERR ? "SquaredErr" : 0;
1901
if( boost_type_str )
1902
cvWriteString( fs, "boosting_type", boost_type_str );
1904
cvWriteInt( fs, "boosting_type", params.boost_type );
1906
if( split_crit_str )
1907
cvWriteString( fs, "splitting_criteria", split_crit_str );
1909
cvWriteInt( fs, "splitting_criteria", params.split_criteria );
1911
cvWriteInt( fs, "ntrees", weak->total );
1912
cvWriteReal( fs, "weight_trimming_rate", params.weight_trim_rate );
1914
data->write_params( fs );
1918
void CvBoost::read_params( CvFileStorage* fs, CvFileNode* fnode )
1920
CV_FUNCNAME( "CvBoost::read_params" );
1926
if( !fnode || !CV_NODE_IS_MAP(fnode->tag) )
1929
data = new CvDTreeTrainData();
1930
CV_CALL( data->read_params(fs, fnode));
1931
data->shared = true;
1933
params.max_depth = data->params.max_depth;
1934
params.min_sample_count = data->params.min_sample_count;
1935
params.max_categories = data->params.max_categories;
1936
params.priors = data->params.priors;
1937
params.regression_accuracy = data->params.regression_accuracy;
1938
params.use_surrogates = data->params.use_surrogates;
1940
temp = cvGetFileNodeByName( fs, fnode, "boosting_type" );
1944
if( temp && CV_NODE_IS_STRING(temp->tag) )
1946
const char* boost_type_str = cvReadString( temp, "" );
1947
params.boost_type = strcmp( boost_type_str, "DiscreteAdaboost" ) == 0 ? DISCRETE :
1948
strcmp( boost_type_str, "RealAdaboost" ) == 0 ? REAL :
1949
strcmp( boost_type_str, "LogitBoost" ) == 0 ? LOGIT :
1950
strcmp( boost_type_str, "GentleAdaboost" ) == 0 ? GENTLE : -1;
1953
params.boost_type = cvReadInt( temp, -1 );
1955
if( params.boost_type < DISCRETE || params.boost_type > GENTLE )
1956
CV_ERROR( CV_StsBadArg, "Unknown boosting type" );
1958
temp = cvGetFileNodeByName( fs, fnode, "splitting_criteria" );
1959
if( temp && CV_NODE_IS_STRING(temp->tag) )
1961
const char* split_crit_str = cvReadString( temp, "" );
1962
params.split_criteria = strcmp( split_crit_str, "Default" ) == 0 ? DEFAULT :
1963
strcmp( split_crit_str, "Gini" ) == 0 ? GINI :
1964
strcmp( split_crit_str, "Misclassification" ) == 0 ? MISCLASS :
1965
strcmp( split_crit_str, "SquaredErr" ) == 0 ? SQERR : -1;
1968
params.split_criteria = cvReadInt( temp, -1 );
1970
if( params.split_criteria < DEFAULT || params.boost_type > SQERR )
1971
CV_ERROR( CV_StsBadArg, "Unknown boosting type" );
1973
params.weak_count = cvReadIntByName( fs, fnode, "ntrees" );
1974
params.weight_trim_rate = cvReadRealByName( fs, fnode, "weight_trimming_rate", 0. );
1982
CvBoost::read( CvFileStorage* fs, CvFileNode* node )
1984
CV_FUNCNAME( "CvBoost::read" );
1989
CvFileNode* trees_fnode;
1990
CvMemStorage* storage;
1994
read_params( fs, node );
1999
trees_fnode = cvGetFileNodeByName( fs, node, "trees" );
2000
if( !trees_fnode || !CV_NODE_IS_SEQ(trees_fnode->tag) )
2001
CV_ERROR( CV_StsParseError, "<trees> tag is missing" );
2003
cvStartReadSeq( trees_fnode->data.seq, &reader );
2004
ntrees = trees_fnode->data.seq->total;
2006
if( ntrees != params.weak_count )
2007
CV_ERROR( CV_StsUnmatchedSizes,
2008
"The number of trees stored does not match <ntrees> tag value" );
2010
CV_CALL( storage = cvCreateMemStorage() );
2011
weak = cvCreateSeq( 0, sizeof(CvSeq), sizeof(CvBoostTree*), storage );
2013
for( i = 0; i < ntrees; i++ )
2015
CvBoostTree* tree = new CvBoostTree();
2016
CV_CALL(tree->read( fs, (CvFileNode*)reader.ptr, this, data ));
2017
CV_NEXT_SEQ_ELEM( reader.seq->elem_size, reader );
2018
cvSeqPush( weak, &tree );
2027
CvBoost::write( CvFileStorage* fs, const char* name ) const
2029
CV_FUNCNAME( "CvBoost::write" );
2036
cvStartWriteStruct( fs, name, CV_NODE_MAP, CV_TYPE_NAME_ML_BOOSTING );
2039
CV_ERROR( CV_StsBadArg, "The classifier has not been trained yet" );
2042
cvStartWriteStruct( fs, "trees", CV_NODE_SEQ );
2044
cvStartReadSeq( weak, &reader );
2046
for( i = 0; i < weak->total; i++ )
2049
CV_READ_SEQ_ELEM( tree, reader );
2050
cvStartWriteStruct( fs, 0, CV_NODE_MAP );
2052
cvEndWriteStruct( fs );
2055
cvEndWriteStruct( fs );
2056
cvEndWriteStruct( fs );
2063
CvBoost::get_weights()
2070
CvBoost::get_subtree_weights()
2072
return subtree_weights;
2077
CvBoost::get_weak_response()
2083
const CvBoostParams&
2084
CvBoost::get_params() const
2089
CvSeq* CvBoost::get_weak_predictors()
2094
const CvDTreeTrainData* CvBoost::get_data() const
2101
CvBoost::CvBoost( const Mat& _train_data, int _tflag,
2102
const Mat& _responses, const Mat& _var_idx,
2103
const Mat& _sample_idx, const Mat& _var_type,
2104
const Mat& _missing_mask,
2105
CvBoostParams _params )
2109
default_model_name = "my_boost_tree";
2110
active_vars = active_vars_abs = orig_response = sum_response = weak_eval =
2111
subsample_mask = weights = subtree_weights = 0;
2113
train( _train_data, _tflag, _responses, _var_idx, _sample_idx,
2114
_var_type, _missing_mask, _params );
2119
CvBoost::train( const Mat& _train_data, int _tflag,
2120
const Mat& _responses, const Mat& _var_idx,
2121
const Mat& _sample_idx, const Mat& _var_type,
2122
const Mat& _missing_mask,
2123
CvBoostParams _params, bool _update )
2125
train_data_hdr = _train_data;
2126
train_data_mat = _train_data;
2127
responses_hdr = _responses;
2128
responses_mat = _responses;
2130
CvMat vidx = _var_idx, sidx = _sample_idx, vtype = _var_type, mmask = _missing_mask;
2132
return train(&train_data_hdr, _tflag, &responses_hdr, vidx.data.ptr ? &vidx : 0,
2133
sidx.data.ptr ? &sidx : 0, vtype.data.ptr ? &vtype : 0,
2134
mmask.data.ptr ? &mmask : 0, _params, _update);
2138
CvBoost::predict( const Mat& _sample, const Mat& _missing,
2139
const Range& slice, bool raw_mode, bool return_sum ) const
2141
CvMat sample = _sample, mmask = _missing;
2142
/*if( weak_responses )
2144
int weak_count = cvSliceLength( slice, weak );
2145
if( weak_count >= weak->total )
2147
weak_count = weak->total;
2148
slice.start_index = 0;
2151
if( !(weak_responses->data && weak_responses->type() == CV_32FC1 &&
2152
(weak_responses->cols == 1 || weak_responses->rows == 1) &&
2153
weak_responses->cols + weak_responses->rows - 1 == weak_count) )
2154
weak_responses->create(weak_count, 1, CV_32FC1);
2155
pwr = &(wr = *weak_responses);
2157
return predict(&sample, _missing.empty() ? 0 : &mmask, 0,
2158
slice == Range::all() ? CV_WHOLE_SEQ : cvSlice(slice.start, slice.end),
2159
raw_mode, return_sum);