    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.imaging.formats.jpeg.segments;
    018
    019import java.io.PrintWriter;
    020
    021import org.apache.commons.imaging.common.BinaryFileParser;
    022
    023public abstract class Segment extends BinaryFileParser {
    024    public final int marker;
    025    public final int length;
    026
    027    public Segment(final int marker, final int length) {
    028        // super();
    029
    030        this.marker = marker;
    031        this.length = length;
    032    }
    033
    034    public void dump(final PrintWriter pw) {
    035        // empty
    036    }
    037
    038    public abstract String getDescription();
    039
    040    @Override
    041    public String toString() {
    042        return "[Segment: " + getDescription() + "]";
    043    }
    044
    045    public String getSegmentType() {
    046
    047        switch (marker) {
    048        case 0xffc0:
    049            return "Start Of Frame, Baseline Dct, Huffman coding";
    050        case 0xffc1:
    051            return "Start Of Frame, Extended sequential Dct, Huffman coding";
    052        case 0xffc2:
    053            return "Start Of Frame, Progressive Dct, Huffman coding";
    054        case 0xffc3:
    055            return "Start Of Frame, Lossless (sequential), Huffman coding";
    056
    057        case 0xffc5:
    058            return "Start Of Frame, Differential sequential Dct, Huffman coding";
    059        case 0xffc6:
    060            return "Start Of Frame, Differential progressive Dct, Huffman coding";
    061        case 0xffc7:
    062            return "Start Of Frame, Differential lossless (sequential), Huffman coding";
    063
    064        case 0xffc8:
    065            return "Start Of Frame, Reserved for JPEG extensions, arithmetic coding";
    066        case 0xffc9:
    067            return "Start Of Frame, Extended sequential Dct, arithmetic coding";
    068        case 0xffca:
    069            return "Start Of Frame, Progressive Dct, arithmetic coding";
    070        case 0xffcb:
    071            return "Start Of Frame, Lossless (sequential), arithmetic coding";
    072
    073        case 0xffcd:
    074            return "Start Of Frame, Differential sequential Dct, arithmetic coding";
    075        case 0xffce:
    076            return "Start Of Frame, Differential progressive Dct, arithmetic coding";
    077        case 0xffcf:
    078            return "Start Of Frame, Differential lossless (sequential), arithmetic coding";
    079
    080        case 0xffc4:
    081            return "Define Huffman table(s)";
    082        case 0xffcc:
    083            return "Define arithmetic coding conditioning(s)";
    084
    085        case 0xffd0:
    086            return "Restart with modulo 8 count 0";
    087        case 0xffd1:
    088            return "Restart with modulo 8 count 1";
    089        case 0xffd2:
    090            return "Restart with modulo 8 count 2";
    091        case 0xffd3:
    092            return "Restart with modulo 8 count 3";
    093        case 0xffd4:
    094            return "Restart with modulo 8 count 4";
    095        case 0xffd5:
    096            return "Restart with modulo 8 count 5";
    097        case 0xffd6:
    098            return "Restart with modulo 8 count 6";
    099        case 0xffd7:
    100            return "Restart with modulo 8 count 7";
    101
    102        case 0xffd8:
    103            return "Start of image";
    104        case 0xffd9:
    105            return "End of image";
    106        case 0xffda:
    107            return "Start of scan";
    108        case 0xffdb:
    109            return "Define quantization table(s)";
    110        case 0xffdc:
    111            return "Define number of lines";
    112        case 0xffdd:
    113            return "Define restart interval";
    114        case 0xffde:
    115            return "Define hierarchical progression";
    116        case 0xffdf:
    117            return "Expand reference component(s)";
    118            // case 0xffd8 :
    119            // return "Reserved for application segments";
    120            // case 0xffd8 :
    121            // return "Reserved for JPEG extensions";
    122        case 0xfffe:
    123            return "Comment";
    124        case 0xff01:
    125            return "For temporary private use in arithmetic coding";
    126            // case 0xffd8 :
    127            // return "Reserved";
    128
    129        default:
    130        }
    131
    132        if ((marker >= 0xff02) && (marker <= 0xffbf)) {
    133            return "Reserved";
    134        }
    135        if ((marker >= 0xffe0) && (marker <= 0xffef)) {
    136            return "APP" + (marker - 0xffe0);
    137        }
    138        if ((marker >= 0xfff0) && (marker <= 0xfffd)) {
    139            return "JPG" + (marker - 0xffe0);
    140        }
    141
    142        return "Unknown";
    143
    144    }
    145
    146}