content: /*
   * Copyright (C) 2019 Adaptech s.r.o., Robert Pösel
   * Copyright (C) 2014 Robert Theis
   *
   * Licensed 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 com.googlecode.leptonica.android;
  
  public class GrayQuant {
  	static {
  		System.loadLibrary("jpeg");
  		System.loadLibrary("pngx");
  		System.loadLibrary("leptonica");
  	}
  
  	/**
  	 * Perform simple (pixelwise) binarization with fixed threshold
  	 * <p>
  	 * Notes:
  	 * <ol>
  	 * <li> If the source pixel is less than the threshold value, the dest will
  	 * be 1; otherwise, it will be 0
  	 * </ol>
  	 *
  	 * @param pixs   Source pix (4 or 8 bpp)
  	 * @param thresh Threshold value
  	 * @return a new Pix image, 1 bpp
  	 */
  	public static Pix pixThresholdToBinary(Pix pixs, int thresh) {
  		if (pixs == null)
  			throw new IllegalArgumentException("Source pix must be non-null");
  		int depth = pixs.getDepth();
  		if (depth != 4 && depth != 8)
  			throw new IllegalArgumentException("Source pix depth must be 4 or 8 bpp");
  		if (depth == 4 && thresh > 16)
  			throw new IllegalArgumentException("4 bpp thresh not in {0-16}");
  		if (depth == 8 && thresh > 256)
  			throw new IllegalArgumentException("8 bpp thresh not in {0-256}");
  
  		long nativePix = nativePixThresholdToBinary(pixs.getNativePix(),
  				thresh);
  
  		if (nativePix == 0)
  			throw new RuntimeException("Failed to perform binarization");
  
  		return new Pix(nativePix);
  	}
  
  	// ***************
  	// * NATIVE CODE *
  	// ***************
  
  	private static native long nativePixThresholdToBinary(long nativePix, int thresh);
  }
  