001/*******************************************************************************
002 * This software is provided as a supplement to the authors' textbooks on digital
003 * image processing published by Springer-Verlag in various languages and editions.
004 * Permission to use and distribute this software is granted under the BSD 2-Clause
005 * "Simplified" License (see http://opensource.org/licenses/BSD-2-Clause).
006 * Copyright (c) 2006-2023 Wilhelm Burger, Mark J. Burge. All rights reserved.
007 * Visit https://imagingbook.com for additional details.
008 ******************************************************************************/
009package imagingbook.common.util;
010
011import java.io.ByteArrayOutputStream;
012import java.io.IOException;
013import java.util.zip.DataFormatException;
014import java.util.zip.Deflater;
015import java.util.zip.Inflater;
016
017/**
018 * This class provides ZIP-compression/decompression of byte arrays.
019 * 
020 * @author WB
021 * @version 2022/09/06
022 */
023public class ZipCompressor {
024
025        private final boolean nowrap;   // true -> ZLIB header and checksum fields will not be used
026        private final int bufsize;
027        
028        public ZipCompressor(int bufsize, boolean nowrap) {
029                this.bufsize = bufsize;
030                this.nowrap = nowrap;
031        }
032
033        public ZipCompressor() {
034                this(1024, true);
035        }
036        
037        // -----------------------------------------------------------
038                        
039        public byte[] compressByteArray(byte[] inputBytes){
040                Deflater deflater = new Deflater(Deflater.BEST_COMPRESSION, nowrap);
041                deflater.setInput(inputBytes);
042                deflater.finish();
043
044                final byte[] buf = new byte[bufsize];
045                byte[] outputBytes = null;
046
047                try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
048                        while (!deflater.finished()) {
049                                int size = deflater.deflate(buf);
050                                bos.write(buf, 0, size);
051                        }
052                        outputBytes = bos.toByteArray();
053                } catch (IOException e) { }
054
055                return outputBytes;
056        }
057
058        public byte[] decompressByteArray(byte[] inputBytes){
059                Inflater inflater = new Inflater(nowrap);
060                inflater.setInput(inputBytes);
061
062                final byte[] buf = new byte[bufsize];
063                byte[] outputBytes = null;
064
065                try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
066                        while(!inflater.finished()){
067                                int size = inflater.inflate(buf);
068                                bos.write(buf, 0, size);
069                        }
070                        outputBytes = bos.toByteArray();
071                } catch (IOException | DataFormatException e) { } 
072
073                return outputBytes;
074        }
075        
076}