Multithreading with Tess4j

[Tuan Nguyen]

Hi Quan,

I tried to use the sample code below, it works with 1 thread when I but
create 3 threads and parsing 3 different images at the same time and I got
error. I had a look at Tesseract.java class and it is a singleton. How
would I do to make Tess4J multithreading?

Thank you very much for reading the question. Hey, I'm also Vietnamese, I
can talk in both English and Vietnamese :)

Error:

Core dump and,

Error in pixGetWidth: pix not defined

If you would like to submit a bug report, please visit:

Error in boxCreate: w and h not both >= 0

http://bugreport.sun.com/bugreport/crash.jsp

Error in pixClipRectangle: pixs not defined

The code:

public class TesseractExample {

public static void main(String[] args) {
    File imageFile = new File("eurotext.tif");
    Tesseract instance = Tesseract.getInstance();  // JNA Interface Mapping
    // Tesseract1 instance = new Tesseract1(); // JNA Direct Mapping

    try {
        String result = instance.doOCR(imageFile);
        System.out.println(result);
    } catch (TesseractException e) {
        System.err.println(e.getMessage());
    }
}

}

[Quan Nguyen]

Hi Tuan,

Can you try Tesseract1 instead?

Thanks.

Quan

[Tuan Nguyen]

Perfect, it works :). Thank you very much Quan!!!

Hey Quan, my last question. Do you have any suggestions that I could use to get the best ocr results? I'm talking image pre-processing and how to use Tess4j to get the best of it, or anything you think I should look into.

Thank you,

[Quan Nguyen]

Tesseract, and Tess4J, contains little preprocessing of images; Leptonica has many routines that you can use to improve your images. Some of the common image enhancements include deskew, dewarp, denoise, despeckle, and threshold/binarize. Tesseract Forum and StackOverflow have a lot of discussion topics on image processing techniques. You may want to research at those sites.