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How to integrate tesseract-ocr library in a catkin project?

asked 2014-07-29 11:53:07 -0500

sirasistant gravatar image

updated 2014-07-29 13:23:42 -0500

Hi, I have no idea of how to integrate the tesseract-ocr library to my project, i use qt creator to code and the library is correctly installed since Qtcreator autocompletes the lines where i use the library but this code fails to compile

#include "text_detector.h"
#include <ros/ros.h>
#include <image_transport/image_transport.h>
#include <cv_bridge/cv_bridge.h>
#include <sensor_msgs/image_encodings.h>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <tesseract/baseapi.h>

image_transport::Subscriber sub;
image_transport::Publisher imPub;
ros::Publisher textPub;
tesseract::TessBaseAPI tess;

void onImageReceived(const sensor_msgs::ImageConstPtr& msg){


int main (int argc, char* argv[]){
    ros::NodeHandle nh;
    ROS_INFO_STREAM("Starting text detection");
    image_transport::ImageTransport it(nh);
    imPub = it.advertise("camera_hsv",1);
    sub = it.subscribe("camera_raw",1,&onImageReceived);
   // textPub=nh.advertise<>("text",1000);

with this compilation error

text_detector.cpp:-1: error: undefined reference to tesseract::TessBaseAPI::TessBaseAPI()' text_detector.cpp:-1: error: undefined reference totesseract::TessBaseAPI::~TessBaseAPI()'

How can i add the library to the project in the cmakelists.txt? Thanks!

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I want to execute this node for my project but i am facing some errors, can you please post me the complete node (.cpp file) and CMakeLists.text.

Kishore Kumar gravatar image Kishore Kumar  ( 2015-07-20 05:56:27 -0500 )edit

Hi @sirasistant! As @Kishore Kumar, I'm also interested in your findings. Are you able to share what you have right now? Thanks in advance!

TSC gravatar image TSC  ( 2015-08-28 13:48:57 -0500 )edit

2 Answers

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answered 2014-07-29 15:04:48 -0500

ahendrix gravatar image

The project's API Samples page gives the proper command-line arguments for building and linking against the tesseract_ocr library: "g++ -o myprogram myprogram.cpp -llept -ltesseract"

In cmake, you can link against libraries using target_link_libraries(); cmake will automatically add the -l flag for you, so all you have to do is:

target_link_libraries(my_tesseract_node lept tesseract)

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That was it! thank you very much :D

sirasistant gravatar image sirasistant  ( 2014-07-30 10:11:47 -0500 )edit

appreciate, saves me a lot of time.

mikelilin gravatar image mikelilin  ( 2015-11-19 06:37:12 -0500 )edit

answered 2015-12-17 21:35:08 -0500

I find another free online ocr to convert image to text, it's using google tesseract ocr 3.02.

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This forum is for questions and answers about ROS (Robot Operating System). How is your answer related to ROS?

ahendrix gravatar image ahendrix  ( 2015-12-17 23:06:39 -0500 )edit

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Asked: 2014-07-29 11:53:07 -0500

Seen: 1,888 times

Last updated: Nov 19 '15