changeset 961:ec1682ed999f

added computation of confusion matrix and improved default parameter for block normalization for SVM classification
author Nicolas Saunier <nicolas.saunier@polymtl.ca>
date Sun, 05 Nov 2017 23:45:47 -0500
parents 0c1d1eeef544
children 64259b9885bf
files classifier.cfg python/ml.py scripts/train-object-classification.py
diffstat 3 files changed, 25 insertions(+), 14 deletions(-) [+]
line wrap: on
line diff
--- a/classifier.cfg	Fri Oct 20 16:59:32 2017 -0400
+++ b/classifier.cfg	Sun Nov 05 23:45:47 2017 -0500
@@ -15,7 +15,7 @@
 # number of cells per block for HoG computation
 hog-ncells-block = 2
 # block normalization method (L1, L1-sqrt, L2, L2-Hys)
-hog-block-norm = L2-Hys
+hog-block-norm = L1-sqrt
 # method to aggregate road user speed
 speed-aggregation-method = median
 # number of frames to ignore at both ends of a series (noisy)
--- a/python/ml.py	Fri Oct 20 16:59:32 2017 -0400
+++ b/python/ml.py	Sun Nov 05 23:45:47 2017 -0500
@@ -19,6 +19,14 @@
 # OpenCV ML models
 #####################
 
+def computeConfusionMatrix(model, samples, responses):
+    'computes the confusion matrix of the classifier (model)'
+    classifications = {}
+    for x,y in zip(samples, responses):
+        predicted = model.predict(x)
+        classifications[(y, predicted)] = classifications.get((y, predicted), 0)+1
+    return classifications
+
 class StatModel(object):
     '''Abstract class for loading/saving model'''    
     def load(self, filename):
@@ -46,8 +54,10 @@
         # self.model.setNu(nu)
         # self.model.setP(p)
 
-    def train(self, samples, responses):
+    def train(self, samples, responses, computePerformance = False):
         self.model.train(samples, responses, params = self.params)
+        if computePerformance:
+            return computeConfusionMatrix(self, samples, responses)
 
     def predict(self, hog):
         return self.model.predict(hog)
--- a/scripts/train-object-classification.py	Fri Oct 20 16:59:32 2017 -0400
+++ b/scripts/train-object-classification.py	Sun Nov 05 23:45:47 2017 -0500
@@ -18,18 +18,11 @@
 parser.add_argument('--nu', dest = 'nu', help = 'SVM nu', default = 0, type = int)
 parser.add_argument('--svmp', dest = 'svmP', help = 'SVM p', default = 0, type = int)
 parser.add_argument('--cfg', dest = 'configFilename', help = 'name of the classifier configuration file', required = True)
-# parser.add_argument('-s', dest = 'rescaleSize', help = 'rescale size of image samples', default = 64, type = int)
-# parser.add_argument('-o', dest = 'nOrientations', help = 'number of orientations in HoG', default = 9, type = int)
-# parser.add_argument('-p', dest = 'nPixelsPerCell', help = 'number of pixels per cell', default = 8, type = int)
-# parser.add_argument('-c', dest = 'nCellsPerBlock', help = 'number of cells per block', default = 2, type = int)
+parser.add_argument('--compute-classifications', dest = 'computeClassifications', help = 'compute the confusion matrix on the training data', action = 'store_true')
 
 args = parser.parse_args()
 classifierParams = storage.ClassifierParameters(args.configFilename)
 
-# rescaleSize = (args.rescaleSize, args.rescaleSize)
-# nPixelsPerCell = (args.nPixelsPerCell, args.nPixelsPerCell)
-# nCellsPerBlock = (args.nCellsPerBlock, args.nCellsPerBlock)
-
 imageDirectories = {'pedestrian': args.directoryName + "/Pedestrians/",
                     'bicycle': args.directoryName + "/Cyclists/",
                     'car': args.directoryName + "/Vehicles/"}
@@ -57,20 +50,28 @@
 # Training the Support Vector Machine
 print "Training Pedestrian-Cyclist-Vehicle Model"
 model = ml.SVM(args.svmType, args.kernelType, args.degree, args.gamma, args.coef0, args.cvalue, args.nu, args.svmP)
-model.train(np.concatenate(trainingSamplesPBV.values()), np.concatenate(trainingLabelsPBV.values()))
+classifications = model.train(np.concatenate(trainingSamplesPBV.values()), np.concatenate(trainingLabelsPBV.values()), True)
+if args.computeClassifications:
+    print(classifications)
 model.save(args.directoryName + "/modelPBV.xml")
 
 print "Training Cyclist-Vehicle Model"
 model = ml.SVM(args.svmType, args.kernelType, args.degree, args.gamma, args.coef0, args.cvalue, args.nu, args.svmP)
-model.train(np.concatenate(trainingSamplesBV.values()), np.concatenate(trainingLabelsBV.values()))
+classifications = model.train(np.concatenate(trainingSamplesBV.values()), np.concatenate(trainingLabelsBV.values()), True)
+if args.computeClassifications:
+    print(classifications)
 model.save(args.directoryName + "/modelBV.xml")
 
 print "Training Pedestrian-Cyclist Model"
 model = ml.SVM(args.svmType, args.kernelType, args.degree, args.gamma, args.coef0, args.cvalue, args.nu, args.svmP)
-model.train(np.concatenate(trainingSamplesPB.values()), np.concatenate(trainingLabelsPB.values()))
+classifications = model.train(np.concatenate(trainingSamplesPB.values()), np.concatenate(trainingLabelsPB.values()), True)
+if args.computeClassifications:
+    print(classifications)
 model.save(args.directoryName + "/modelPB.xml")
 
 print "Training Pedestrian-Vehicle Model"
 model = ml.SVM(args.svmType, args.kernelType, args.degree, args.gamma, args.coef0, args.cvalue, args.nu, args.svmP)
-model.train(np.concatenate(trainingSamplesPV.values()), np.concatenate(trainingLabelsPV.values()))
+classifications = model.train(np.concatenate(trainingSamplesPV.values()), np.concatenate(trainingLabelsPV.values()), True)
+if args.computeClassifications:
+    print(classifications)
 model.save(args.directoryName + "/modelPV.xml")