Getting UnsatisfiedLinkError: no jnilept in java.library.path when I create TessBaseAPI

Question

I am new to java cpp and tesseract-ocr. I am stuck with one issue from couple of hours. I am getting UnsatisfiedLinkError: no jnilept in java.library.path when I cre

Answer 1

you could clone or download the project:

https://github.com/bytedeco/javacpp-presets#the-cppbuildsh-scripts

then build the modules: JavaCPP Presets for Tesseract and JavaCPP Presets for Leptonica;

(to build the leptonica project you maybe need to install nasm https://www.nasm.us/)

(to build the entire javacpp-presets project you also have to install cmake)

that would create the native libraries:

libjnilept.so and libjnitesseract.so

then you have to specify the jni.library.path

You can do it with:

System.setProperty(JAVA_LIBRARY_PATH, tmpDirName);
/* Optionally add these two lines */
System.setProperty("jna.library.path", tmpDirName);
System.setProperty("jni.library.path", tmpDirName);
final Field fieldSysPath;

fieldSysPath = ClassLoader.class.getDeclaredField(SYS_PATHS);

fieldSysPath.setAccessible(true);
fieldSysPath.set(null, null);

(you could instead specify the -Djava.library.path= on the virtual machine options)

you only have to put the generated files: libjnilept.so and libjnitesseract.so in some folder and set this path for: jni.library.path

<dependency>
    <groupId>org.bytedeco.javacpp-presets</groupId>
    <artifactId>tesseract</artifactId>           
    <version>4.0.0-1.4.4</version>            
</dependency>

<dependency>
    <groupId>org.bytedeco.javacpp-presets</groupId>
    <artifactId>leptonica</artifactId>
    <version>1.77.0-1.4.4</version> 
</dependency>

you can also try to add

<dependency>    
    <groupId>org.bytedeco.javacpp-presets</groupId>
    <artifactId>leptonica-platform</artifactId> 
    <version>1.77.0-1.4.4</version>
</dependency> 

<dependency>
    <groupId>org.bytedeco.javacpp-presets</groupId>
    <artifactId>tesseract-platform</artifactId>
    <version>4.0.0-1.4.4</version>
</dependency>

and add into the build a maven-assembly-plugin

<build>
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <configuration>
                <archive>
                    <manifest>
                         mainClass>fully.qualified.MainClass</mainClass>
                    </manifest>
                </archive>
                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>
            </configuration>
            <!-- new -->
            <executions>
                <execution>
                    <id>make-assembly</id> 
                    <phase>package</phase> 
                    <goals>
                        <goal>single</goal> 
                    </goals>
                </execution>
            </executions>
        </plugin>   
</build>

 

---

 

Also, you could also get an error like this:

sscanf(line, "%" QUOTED_TOKENSIZE "s %" QUOTED_TOKENSIZE "s %f %f",
linear_token, essential_token, &ParamDesc[i].Min, &ParamDesc[i].Max) == 4
:Error:Assert failed:in file clusttool.cpp, line 73
#
# A fatal error has been detected by the Java Runtime Environment:

Due to Tesseract's locale requirements, export LC_ALL=C is required before running any client programs.

so:

       <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>exec-maven-plugin</artifactId>
            <version>1.6.0</version>
            <executions>
                <execution>
                    <goals>
                        <goal>exec</goal>
                    </goals>
                </execution>
            </executions>
            <configuration> 
                <environmentVariables>  
                    <LC_ALL>C</LC_ALL>
                </environmentVariables>
                <executable>java</executable>
                <arguments>
                    <argument>-classpath</argument>
                    <classpath />
                    <argument>${classpath}</argument>
                </arguments>
            </configuration>
        </plugin> 

source:
    - https://github.com/nguyenq/tess4j/issues/106
    - https://github.com/sirfz/tesserocr/issues/165