org.apache.tika.parser.ocr.TesseractOCRConfig Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.tika.parser.ocr;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.Serializable;
import java.util.Properties;
/**
* Configuration for TesseractOCRParser.
*
* This allows to enable TesseractOCRParser and set its parameters:
*
* TesseractOCRConfig config = new TesseractOCRConfig();
* config.setTesseractPath(tesseractFolder);
* parseContext.set(TesseractOCRConfig.class, config);
*
*
* Parameters can also be set by either editing the existing TesseractOCRConfig.properties file in,
* tika-parser/src/main/resources/org/apache/tika/parser/ocr, or overriding it by creating your own
* and placing it in the package org/apache/tika/parser/ocr on the classpath.
*
*/
public class TesseractOCRConfig implements Serializable{
private static final long serialVersionUID = -4861942486845757891L;
// Path to tesseract installation folder, if not on system path.
private String tesseractPath = "";
// Language dictionary to be used.
private String language = "eng";
// Tesseract page segmentation mode.
private String pageSegMode = "1";
// Minimum file size to submit file to ocr.
private int minFileSizeToOcr = 0;
// Maximum file size to submit file to ocr.
private int maxFileSizeToOcr = Integer.MAX_VALUE;
// Maximum time (seconds) to wait for the ocring process termination
private int timeout = 120;
/**
* Default contructor.
*/
public TesseractOCRConfig() {
init(this.getClass().getResourceAsStream("TesseractOCRConfig.properties"));
}
/**
* Loads properties from InputStream and then tries to close InputStream.
* If there is an IOException, this silently swallows the exception
* and goes back to the default.
*
* @param is
*/
public TesseractOCRConfig(InputStream is) {
init(is);
}
private void init(InputStream is) {
if (is == null) {
return;
}
Properties props = new Properties();
try {
props.load(is);
} catch (IOException e) {
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
//swallow
}
}
}
setTesseractPath(
getProp(props, "tesseractPath", getTesseractPath()));
setLanguage(
getProp(props, "language", getLanguage()));
setPageSegMode(
getProp(props, "pageSegMode", getPageSegMode()));
setMinFileSizeToOcr(
getProp(props, "minFileSizeToOcr", getMinFileSizeToOcr()));
setMaxFileSizeToOcr(
getProp(props, "maxFileSizeToOcr", getMaxFileSizeToOcr()));
setTimeout(
getProp(props, "timeout", getTimeout()));
}
/** @see #setTesseractPath(String tesseractPath)*/
public String getTesseractPath() {
return tesseractPath;
}
/**
* Set tesseract installation folder, needed if it is not on system path.
*/
public void setTesseractPath(String tesseractPath) {
if(!tesseractPath.isEmpty() && !tesseractPath.endsWith(File.separator))
tesseractPath += File.separator;
this.tesseractPath = tesseractPath;
}
/** @see #setLanguage(String language)*/
public String getLanguage() {
return language;
}
/**
* Set tesseract language dictionary to be used. Default is "eng".
* Multiple languages may be specified, separated by plus characters.
*/
public void setLanguage(String language) {
if (!language.matches("([A-Za-z](\\+?))*")) {
throw new IllegalArgumentException("Invalid language code");
}
this.language = language;
}
/** @see #setPageSegMode(String pageSegMode)*/
public String getPageSegMode() {
return pageSegMode;
}
/**
* Set tesseract page segmentation mode.
* Default is 1 = Automatic page segmentation with OSD (Orientation and Script Detection)
*/
public void setPageSegMode(String pageSegMode) {
if (!pageSegMode.matches("[1-9]|10")) {
throw new IllegalArgumentException("Invalid language code");
}
this.pageSegMode = pageSegMode;
}
/** @see #setMinFileSizeToOcr(int minFileSizeToOcr)*/
public int getMinFileSizeToOcr() {
return minFileSizeToOcr;
}
/**
* Set minimum file size to submit file to ocr.
* Default is 0.
*/
public void setMinFileSizeToOcr(int minFileSizeToOcr) {
this.minFileSizeToOcr = minFileSizeToOcr;
}
/** @see #setMaxFileSizeToOcr(int maxFileSizeToOcr)*/
public int getMaxFileSizeToOcr() {
return maxFileSizeToOcr;
}
/**
* Set maximum file size to submit file to ocr.
* Default is Integer.MAX_VALUE.
*/
public void setMaxFileSizeToOcr(int maxFileSizeToOcr) {
this.maxFileSizeToOcr = maxFileSizeToOcr;
}
/**
* Set maximum time (seconds) to wait for the ocring process to terminate.
* Default value is 120s.
*/
public void setTimeout(int timeout) {
this.timeout = timeout;
}
/** @see #setTimeout(int timeout)*/
public int getTimeout() {
return timeout;
}
/**
* Get property from the properties file passed in.
* @param properties properties file to read from.
* @param property the property to fetch.
* @param defaultMissing default parameter to use.
* @return the value.
*/
private int getProp(Properties properties, String property, int defaultMissing) {
String p = properties.getProperty(property);
if (p == null || p.isEmpty()){
return defaultMissing;
}
try {
return Integer.parseInt(p);
} catch (Throwable ex) {
throw new RuntimeException(String.format("Cannot parse TesseractOCRConfig variable %s, invalid integer value", property), ex);
}
}
/**
* Get property from the properties file passed in.
* @param properties properties file to read from.
* @param property the property to fetch.
* @param defaultMissing default parameter to use.
* @return the value.
*/
private String getProp(Properties properties, String property, String defaultMissing) {
return properties.getProperty(property, defaultMissing);
}
}