java - 创建TessBaseAPI时获取UnsatisfiedLinkError : no jnilept in java. library.path

我是java cpp和tesseract-ocr的新手。我几个小时都陷入一个问题。
我在创建TessBaseAPI时遇到UnsatisfiedLinkError:java.library.path中没有异常。下面是我的代码。

public static void tesseractForPdf(String filePath) throws Exception {
    BytePointer outText;

    TessBaseAPI api = new TessBaseAPI();//getting the UnsatisfiedLinkError exception here.
    // Initialize tesseract-ocr with English, without specifying tessdata path
    if (api.Init(".", "ENG") != 0) {
        System.err.println("Could not initialize tesseract.");
        System.exit(1);
    }

    // Open input image with leptonica library
    PIX image = pixRead(filePath);
    api.SetImage(image);
    // Get OCR result
    outText = api.GetUTF8Text();
    String string = outText.getString();
    System.out.println("OCR output:\n" + string);

    // Destroy used object and release memory
    api.End();
    outText.deallocate();
    pixDestroy(image);
}

异常(exception)，我正在使用TessBaseAPI api = new TessBaseAPI();线

Exception in thread "main" java.lang.UnsatisfiedLinkError: no jnilept in java.library.path
at java.lang.ClassLoader.loadLibrary(Unknown Source)
at java.lang.Runtime.loadLibrary0(Unknown Source)
at java.lang.System.loadLibrary(Unknown Source)
at org.bytedeco.javacpp.Loader.loadLibrary(Loader.java:702)
at org.bytedeco.javacpp.Loader.load(Loader.java:500)
at org.bytedeco.javacpp.Loader.load(Loader.java:417)
at org.bytedeco.javacpp.lept.<clinit>(lept.java:10)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.bytedeco.javacpp.Loader.load(Loader.java:472)
at org.bytedeco.javacpp.Loader.load(Loader.java:417)
at org.bytedeco.javacpp.tesseract$TessBaseAPI.<clinit>(tesseract.java:3648)
at om.practiceproblems.BasicTesseractExampleTest.givenTessBaseApi_whenImageOcrd_thenTextDisplayed(BasicTesseractExampleTest.java:35)
at com.practiceproblems.BasicTesseractExampleTest.main(BasicTesseractExampleTest.java:22)
Caused by: java.lang.UnsatisfiedLinkError: no liblept in java.library.path
at java.lang.ClassLoader.loadLibrary(Unknown Source)
at java.lang.Runtime.loadLibrary0(Unknown Source)
at java.lang.System.loadLibrary(Unknown Source)
at org.bytedeco.javacpp.Loader.loadLibrary(Loader.java:702)
at org.bytedeco.javacpp.Loader.load(Loader.java:491)
... 9 more

我在示例中将java-presets库tesseract-3.04.01-1.2和leptonica-1.73-1.2.jar与javacpp-1.2.1一起使用。我有Windows操作系统。
我确实看到了https://github.com/bytedeco/javacpp-presets/issues/46以及关于SO和github的一些讨论，这些讨论指出此问题已在jacacpp-1.1本身中修复，但我使用的是javacpp1.2。
对于解决问题或找到根本原因的任何帮助，我将非常感谢。

最佳答案

您可以克隆或下载项目:

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

然后构建模块:用于Tesseract的JavaCPP预设和用于Leptonica的JavaCPP预设；

(要构建leptonica项目，您可能需要安装 nasm
https://www.nasm.us/)

(要构建整个javacpp-presets项目，还必须安装cmake )

这将创建 native 库:

libjnilept.so和libjnitesseract.so

那么你必须指定jni.library.path

您可以执行以下操作:

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);

(您可以改为在虚拟机选项上指定-Djava.library.path =)

您只需要放入生成的文件:
libjnilept.so和libjnitesseract.so在某个文件夹中，并将此路径设置为: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>

您也可以尝试添加

<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>

并在构建中添加一个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>

此外，您还会收到如下错误:

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:

所以:

       <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>