my_ocr.cpp

#include <stdio.h>
#include <iostream>
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/flann/miniflann.hpp"

#include <tesseract/baseapi.h>

using namespace cv;
using namespace std;
using namespace cv::flann;

// compile >> g++ <file.cpp> -o app `pkg-config --cflags --libs opencv` -ltesseract
// app "image.jpg"


int main( int argc, char** argv ) {
    Mat img = imread(argv[1]);
    cvtColor(img,img,CV_BGR2GRAY);
    cv::Mat img_bw;
    cv::threshold(img, img_bw, 128.0, 255.0, THRESH_BINARY);
    bitwise_not ( img_bw, img_bw );

    tesseract::TessBaseAPI tess;
    tess.Init(NULL, "eng", tesseract::OEM_DEFAULT);
    tess.SetVariable("tessedit_char_whitelist", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
    tess.SetPageSegMode(tesseract::PSM_SINGLE_BLOCK);
    tess.SetImage((uchar*)img_bw.data, img_bw.cols, img_bw.rows, 1, img_bw.cols);

    char* out = tess.GetUTF8Text();
    std::cout << out << std::endl;

    imshow("img",img_bw);
    waitKey(0);
    return 0;
}