TesseractTextFrame.java

/**
 * Licensed to The Apereo Foundation under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 *
 *
 * The Apereo Foundation licenses this file to you under the Educational
 * Community 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://opensource.org/licenses/ecl2.txt
 *
 * 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.opencastproject.textextractor.tesseract;

import org.opencastproject.textextractor.api.TextFrame;
import org.opencastproject.textextractor.api.TextLine;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;

/**
 * This class represents a tesseract output frame that holds a number of lines found on an image. Note that Tesseract
 * does not inlcude positioning or other information with the text output.
 */
public class TesseractTextFrame implements TextFrame {

  /** Words found on an output frame */
  protected ArrayList<TextLine> lines = new ArrayList<TextLine>();

  /**
   * Parses the tesseract output file and extracts the text information contained therein.
   *
   * @param is
   *          the input stream
   * @return the ocropus text information
   * @throws IOException
   *           if reading the ocropus output fails
   */
  public static TextFrame parse(InputStream is) throws IOException {
    BufferedReader in = new BufferedReader(new InputStreamReader(is, "UTF-8"));
    String line;
    TesseractTextFrame textFrame = new TesseractTextFrame();

    while ((line = in.readLine()) != null) {
      textFrame.lines.add(new TesseractLine(line));
    }

    return textFrame;
  }

  /**
   * {@inheritDoc}
   *
   * @see org.opencastproject.textextractor.api.TextFrame#hasText()
   */
  @Override
  public boolean hasText() {
    return lines.size() > 0;
  }

  /**
   * {@inheritDoc}
   *
   * @see org.opencastproject.textextractor.api.TextFrame#getLines()
   */
  @Override
  public TextLine[] getLines() {
    return lines.toArray(new TesseractLine[lines.size()]);
  }

}