Using Tesseract from java

问题:

I'm trying to build a sample application in java that will read an image file and just output the text extracted from the image. I found the Tesseract project which seems promising, however, its in c++. In order to use it, should I simply run it as a command line from my java app Runtime.exec(...) ? Or is there a better solution, maybe a JAR? Additionally, this is just a sample app, would running it as a command line app be a concern from scalability perspective?

回答1:

Now tesseract is provided by the javacv project, this is a far better option than using Tess4J since all that is required is adding a single dependency to your pom file, the native libs for your platform will then be downloaded and linked automatically for you by the javacv tesseract version.

I've created an example maven project here - https://github.com/piersy/BasicTesseractExample

and also an example gradle project here - https://github.com/piersy/BasicTesseractExampleGradle

For this to work on my ubuntu machine I needed to update my install of libstdc++6

I achieved this by running the following although just installing libstdc++6 may work for you.

sudo add-apt-repository ppa:ubuntu-toolchain-r/test 
sudo apt-get update
sudo apt-get install libstdc++6

Note the gradle project does not perform the automatic install but is is still a hell of a lot simpler than using Tess4J

The javacv project is here - https://github.com/bytedeco/javacpp-presets/tree/master/tesseract

Big props to the javacv guys, only wish I'd found this earlier as it would have saved me a week of getting tess4j to work on multiple platforms!

回答2:

I have used the tesseract project in my java code. All you need to do is

1. Get the tess4j jni wrapper for tesseract.
2. Open the tess4j proj in your ide and add the source packages and libs into your own
   project.
3. Write the code creating an instance for the tesseract class and then use it for
   performing the OCR.

Please have a look into this http://tphangout.com/?p=18

It gives instructions on how to build a java project to read an image and convert it into text using the tesseract OCR API.

回答3:

Have you tried tess4j: http://tess4j.sourceforge.net/.

It is JNI wrapper of tesseract for windows.

回答4:

I've forked the Basic Git Repo and updated it so that it can be compatible with Tesseract-ocr version (4.x.x) and bytedeco javacpp-presets version (1.4.3).

BasicTesseractExampleVer4

回答5:

just tried https://github.com/piersy/BasicTesseractExample

looks like it works, using just one dependency to this:

<dependency>
      <groupId>org.bytedeco.javacpp-presets</groupId>
      <artifactId>tesseract</artifactId>
      <version>3.03-rc1-0.11</version>
</dependency>

which is here: https://github.com/bytedeco/javacpp-presets/tree/master/tesseract

cheers corrado

回答6:

I used this How to Test Toast Messages using Appium?

with this

    <dependency>
        <groupId>net.sourceforge.tess4j</groupId>
        <artifactId>tess4j</artifactId>
        <version>3.2.1</version>
    </dependency>