classify_image_class_knnT_classify_image_class_knnClassifyImageClassKnnClassifyImageClassKnnclassify_image_class_knn (Operator)

Name

classify_image_class_knnT_classify_image_class_knnClassifyImageClassKnnClassifyImageClassKnnclassify_image_class_knn — Classify an image with a k-Nearest-Neighbor classifier.

Signature

Description

classify_image_class_knnclassify_image_class_knnClassifyImageClassKnnClassifyImageClassKnnclassify_image_class_knn performs a pixel classification with a k-Nearest-Neighbor classifier (k-NN) KNNHandleKNNHandleKNNHandleKNNHandleknnhandle on the multichannel image ImageImageImageimageimage. Before calling classify_image_class_knnclassify_image_class_knnClassifyImageClassKnnClassifyImageClassKnnclassify_image_class_knn the k-NN classifier must be trained with train_class_knntrain_class_knnTrainClassKnnTrainClassKnntrain_class_knn. ImageImageImageimageimage must have NumDimNumDimNumDimnumDimnum_dim channels, as specified with create_class_knncreate_class_knnCreateClassKnnCreateClassKnncreate_class_knn. On output, ClassRegionsClassRegionsClassRegionsclassRegionsclass_regions contains NumClassesNumClassesNumClassesnumClassesnum_classes regions as the result of the classification. Note that the order of the regions that are returned in ClassRegionsClassRegionsClassRegionsclassRegionsclass_regions corresponds to the order of the classes as defined by the training regions in add_samples_image_class_knnadd_samples_image_class_knnAddSamplesImageClassKnnAddSamplesImageClassKnnadd_samples_image_class_knn. The parameter RejectionThresholdRejectionThresholdRejectionThresholdrejectionThresholdrejection_threshold can be used to reject pixels that have an uncertain classification. RejectionThresholdRejectionThresholdRejectionThresholdrejectionThresholdrejection_threshold represents a threshold on the distance to the nearest neighbor returned by the classification. All pixels having a probability below RejectionThresholdRejectionThresholdRejectionThresholdrejectionThresholdrejection_threshold are not assigned to any class. DistanceImageDistanceImageDistanceImagedistanceImagedistance_image contains the distance of each pixel to its nearest neighbor.

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Automatically parallelized on internal data level.

Parameters

Example (HDevelop)

read_image (Image, 'ic')
gen_rectangle1 (Board, 80, 320, 110, 350)
gen_rectangle1 (Capacitor, 359, 263, 371, 302)
gen_rectangle1 (Resistor, 200, 252, 290, 256)
gen_rectangle1 (IC, 180, 135, 216, 165)
concat_obj (Board, Capacitor, Classes)
concat_obj (Classes, Resistor, Classes)
concat_obj (Classes, IC, Classes)
create_class_knn (3, KNNHandle)
add_samples_image_class_knn (Image, Classes, KNNHandle)
get_sample_num_class_knn (KNNHandle, NumSamples)
train_class_knn (KNNHandle, [], [])
classify_image_class_knn (Image, ClassRegions, DistanceImage, \
                          KNNHandle, 0.5)
dev_display (ClassRegions)

Result

If the parameters are valid, the operator classify_image_class_knnclassify_image_class_knnClassifyImageClassKnnClassifyImageClassKnnclassify_image_class_knn returns the value 2 ( H_MSG_TRUE) . If necessary an exception is raised.

Possible Predecessors

train_class_knntrain_class_knnTrainClassKnnTrainClassKnntrain_class_knn, read_class_knnread_class_knnReadClassKnnReadClassKnnread_class_knn

Alternatives

classify_image_class_svmclassify_image_class_svmClassifyImageClassSvmClassifyImageClassSvmclassify_image_class_svm, classify_image_class_mlpclassify_image_class_mlpClassifyImageClassMlpClassifyImageClassMlpclassify_image_class_mlp, classify_image_class_gmmclassify_image_class_gmmClassifyImageClassGmmClassifyImageClassGmmclassify_image_class_gmm, classify_image_class_lutclassify_image_class_lutClassifyImageClassLutClassifyImageClassLutclassify_image_class_lut, class_ndim_normclass_ndim_normClassNdimNormClassNdimNormclass_ndim_norm, class_2dim_supclass_2dim_supClass2dimSupClass2dimSupclass_2dim_sup

See also

add_samples_image_class_knnadd_samples_image_class_knnAddSamplesImageClassKnnAddSamplesImageClassKnnadd_samples_image_class_knn, create_class_knncreate_class_knnCreateClassKnnCreateClassKnncreate_class_knn

Module

Foundation