org.opencv.text

Class OCRHMMDecoder

java.lang.Object

org.opencv.text.BaseOCR

org.opencv.text.OCRHMMDecoder

public class OCRHMMDecoder
extends BaseOCR

OCRHMMDecoder class provides an interface for OCR using Hidden Markov Models. Note:

• (C++) An example on using OCRHMMDecoder recognition combined with scene text detection can be found at the webcam_demo sample: <https://github.com/opencv/opencv_contrib/blob/master/modules/text/samples/webcam_demo.cpp>

Field Summary

Fields inherited from class org.opencv.text.BaseOCR

nativeObj

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	OCRHMMDecoder(long addr)

Method Summary

Modifier and Type	Method and Description
static OCRHMMDecoder	__fromPtr__(long addr)
static OCRHMMDecoder	create(OCRHMMDecoder_ClassifierCallback classifier, String vocabulary, Mat transition_probabilities_table, Mat emission_probabilities_table) Creates an instance of the OCRHMMDecoder class.
static OCRHMMDecoder	create(OCRHMMDecoder_ClassifierCallback classifier, String vocabulary, Mat transition_probabilities_table, Mat emission_probabilities_table, int mode) Creates an instance of the OCRHMMDecoder class.
static OCRHMMDecoder	create(String filename, String vocabulary, Mat transition_probabilities_table, Mat emission_probabilities_table) Creates an instance of the OCRHMMDecoder class.
static OCRHMMDecoder	create(String filename, String vocabulary, Mat transition_probabilities_table, Mat emission_probabilities_table, int mode) Creates an instance of the OCRHMMDecoder class.
static OCRHMMDecoder	create(String filename, String vocabulary, Mat transition_probabilities_table, Mat emission_probabilities_table, int mode, int classifier) Creates an instance of the OCRHMMDecoder class.
protected void	finalize()
String	run(Mat image, int min_confidence) Recognize text using HMM.
String	run(Mat image, int min_confidence, int component_level) Recognize text using HMM.
String	run(Mat image, Mat mask, int min_confidence)
String	run(Mat image, Mat mask, int min_confidence, int component_level)

Methods inherited from class org.opencv.text.BaseOCR

getNativeObjAddr

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

OCRHMMDecoder

protected OCRHMMDecoder(long addr)

Method Detail

__fromPtr__

public static OCRHMMDecoder __fromPtr__(long addr)

run

public String run(Mat image,
                  int min_confidence,
                  int component_level)

Recognize text using HMM. Takes an image and a mask (where each connected component corresponds to a segmented character) on input and returns recognized text in the output_text parameter. Optionally provides also the Rects for individual text elements found (e.g. words), and the list of those text elements with their confidence values.

Parameters:

image - Input image CV_8UC1 or CV_8UC3 with a single text line (or word). text elements found (e.g. words). recognition of individual text elements found (e.g. words). for the recognition of individual text elements found (e.g. words).

component_level - Only OCR_LEVEL_WORD is supported.

min_confidence - automatically generated

Returns:

automatically generated

run

public String run(Mat image,
                  int min_confidence)

Recognize text using HMM. Takes an image and a mask (where each connected component corresponds to a segmented character) on input and returns recognized text in the output_text parameter. Optionally provides also the Rects for individual text elements found (e.g. words), and the list of those text elements with their confidence values.

Parameters:

image - Input image CV_8UC1 or CV_8UC3 with a single text line (or word). text elements found (e.g. words). recognition of individual text elements found (e.g. words). for the recognition of individual text elements found (e.g. words).

min_confidence - automatically generated

Returns:

automatically generated

run

public String run(Mat image,
                  Mat mask,
                  int min_confidence,
                  int component_level)

run

public String run(Mat image,
                  Mat mask,
                  int min_confidence)

create

public static OCRHMMDecoder create(OCRHMMDecoder_ClassifierCallback classifier,
                                   String vocabulary,
                                   Mat transition_probabilities_table,
                                   Mat emission_probabilities_table,
                                   int mode)

Creates an instance of the OCRHMMDecoder class. Initializes HMMDecoder.

Parameters:

classifier - The character classifier with built in feature extractor.

vocabulary - The language vocabulary (chars when ascii english text). vocabulary.size() must be equal to the number of classes of the classifier.

transition_probabilities_table - Table with transition probabilities between character pairs. cols == rows == vocabulary.size().

emission_probabilities_table - Table with observation emission probabilities. cols == rows == vocabulary.size().

mode - HMM Decoding algorithm. Only OCR_DECODER_VITERBI is available for the moment (<http://en.wikipedia.org/wiki/Viterbi_algorithm>).

Returns:

automatically generated

create

public static OCRHMMDecoder create(OCRHMMDecoder_ClassifierCallback classifier,
                                   String vocabulary,
                                   Mat transition_probabilities_table,
                                   Mat emission_probabilities_table)

Creates an instance of the OCRHMMDecoder class. Initializes HMMDecoder.

Parameters:

classifier - The character classifier with built in feature extractor.

vocabulary - The language vocabulary (chars when ascii english text). vocabulary.size() must be equal to the number of classes of the classifier.

transition_probabilities_table - Table with transition probabilities between character pairs. cols == rows == vocabulary.size().

emission_probabilities_table - Table with observation emission probabilities. cols == rows == vocabulary.size(). (<http://en.wikipedia.org/wiki/Viterbi_algorithm>).

Returns:

automatically generated

create

public static OCRHMMDecoder create(String filename,
                                   String vocabulary,
                                   Mat transition_probabilities_table,
                                   Mat emission_probabilities_table,
                                   int mode,
                                   int classifier)

Creates an instance of the OCRHMMDecoder class. Loads and initializes HMMDecoder from the specified path

Parameters:

filename - automatically generated

vocabulary - automatically generated

transition_probabilities_table - automatically generated

emission_probabilities_table - automatically generated

mode - automatically generated

classifier - automatically generated

Returns:

automatically generated

create

public static OCRHMMDecoder create(String filename,
                                   String vocabulary,
                                   Mat transition_probabilities_table,
                                   Mat emission_probabilities_table,
                                   int mode)

Creates an instance of the OCRHMMDecoder class. Loads and initializes HMMDecoder from the specified path

Parameters:

filename - automatically generated

vocabulary - automatically generated

transition_probabilities_table - automatically generated

emission_probabilities_table - automatically generated

mode - automatically generated

Returns:

automatically generated

create

public static OCRHMMDecoder create(String filename,
                                   String vocabulary,
                                   Mat transition_probabilities_table,
                                   Mat emission_probabilities_table)

Creates an instance of the OCRHMMDecoder class. Loads and initializes HMMDecoder from the specified path

Parameters:

filename - automatically generated

vocabulary - automatically generated

transition_probabilities_table - automatically generated

emission_probabilities_table - automatically generated

Returns:

automatically generated

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class BaseOCR

Throws:

Throwable