OpenCV_4.2.0/opencv_contrib-4.2.0/modules/text/samples/character_recognition.cpp

56 lines
1.9 KiB
C++

/*
* cropped_word_recognition.cpp
*
* A demo program of text recognition in a given cropped word.
* Shows the use of the OCRBeamSearchDecoder class API using the provided default classifier.
*
* Created on: Jul 9, 2015
* Author: Lluis Gomez i Bigorda <lgomez AT cvc.uab.es>
*/
#include "opencv2/text.hpp"
#include "opencv2/core/utility.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/imgproc.hpp"
#include <iostream>
using namespace std;
using namespace cv;
using namespace cv::text;
int main(int argc, char* argv[])
{
cout << endl << argv[0] << endl << endl;
cout << "A demo program of Scene Text Character Recognition: " << endl;
cout << "Shows the use of the OCRBeamSearchDecoder::ClassifierCallback class using the Single Layer CNN character classifier described in:" << endl;
cout << "Coates, Adam, et al. \"Text detection and character recognition in scene images with unsupervised feature learning.\" ICDAR 2011." << endl << endl;
Mat image;
if(argc>1)
image = imread(argv[1]);
else
{
cout << " Usage: " << argv[0] << " <input_image>" << endl;
cout << " the input image must contain a single character (e.g. scenetext_char01.jpg)." << endl << endl;
return(0);
}
string vocabulary = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; // must have the same order as the classifier output classes
Ptr<OCRHMMDecoder::ClassifierCallback> ocr = loadOCRHMMClassifierCNN("OCRBeamSearch_CNN_model_data.xml.gz");
double t_r = (double)getTickCount();
vector<int> out_classes;
vector<double> out_confidences;
ocr->eval(image, out_classes, out_confidences);
cout << "OCR output = \"" << vocabulary[out_classes[0]] << "\" with confidence "
<< out_confidences[0] << ". Evaluated in "
<< ((double)getTickCount() - t_r)*1000/getTickFrequency() << " ms." << endl << endl;
return 0;
}