/* * 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.pdfbox.pdmodel.graphics.predictor; /** * * * In an Uptimum encoded image, each line takes up width*bpp+1 bytes. The first * byte holds a number that signifies which algorithm encoded the line. * * @author xylifyx@yahoo.co.uk * @version $Revision: 1.1 $ */ public class Optimum extends PredictorAlgorithm { /** * {@inheritDoc} */ public void checkBufsiz(byte[] filtered, byte[] raw) { if (filtered.length != (getWidth() * getBpp() + 1) * getHeight()) { throw new IllegalArgumentException( "filtered.length != (width*bpp + 1) * height, " + filtered.length + " " + (getWidth() * getBpp() + 1) * getHeight() + "w,h,bpp=" + getWidth() + "," + getHeight() + "," + getBpp()); } if (raw.length != getWidth() * getHeight() * getBpp()) { throw new IllegalArgumentException( "raw.length != width * height * bpp, raw.length=" + raw.length + " w,h,bpp=" + getWidth() + "," + getHeight() + "," + getBpp()); } } /** * {@inheritDoc} */ public void encodeLine(byte[] src, byte[] dest, int srcDy, int srcOffset, int destDy, int destOffset) { throw new UnsupportedOperationException("encodeLine"); } /** * {@inheritDoc} */ public void decodeLine(byte[] src, byte[] dest, int srcDy, int srcOffset, int destDy, int destOffset) { throw new UnsupportedOperationException("decodeLine"); } /** * {@inheritDoc} */ public void encode(byte[] src, byte[] dest) { checkBufsiz(dest, src); throw new UnsupportedOperationException("encode"); } /** * Filter indexed by byte code. */ PredictorAlgorithm[] filter = { new None(), new Sub(), new Up(), new Average(), new Paeth() }; /** * {@inheritDoc} */ public void setBpp(int bpp) { super.setBpp(bpp); for (int i = 0; i < filter.length; i++) { filter[i].setBpp(bpp); } } /** * {@inheritDoc} */ public void setHeight(int height) { super.setHeight(height); for (int i = 0; i < filter.length; i++) { filter[i].setHeight(height); } } /** * {@inheritDoc} */ public void setWidth(int width) { super.setWidth(width); for (int i = 0; i < filter.length; i++) { filter[i].setWidth(width); } } /** * {@inheritDoc} */ public void decode(byte[] src, byte[] dest) { checkBufsiz(src, dest); int bpl = getWidth() * getBpp(); int srcDy = bpl + 1; for (int y = 0; y < getHeight(); y++) { PredictorAlgorithm f = filter[src[y * srcDy]]; int srcOffset = y * srcDy + 1; f.decodeLine(src, dest, srcDy, srcOffset, bpl, y * bpl); } } }