mirror of
https://github.com/starovoid/rxing.git
synced 2026-07-26 12:22:34 +00:00
300 lines
9.6 KiB
Java
300 lines
9.6 KiB
Java
/*
|
|
* Copyright 2010 ZXing authors
|
|
*
|
|
* 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.google.zxing.oned;
|
|
|
|
import com.google.zxing.BarcodeFormat;
|
|
import com.google.zxing.ChecksumException;
|
|
import com.google.zxing.DecodeHintType;
|
|
import com.google.zxing.FormatException;
|
|
import com.google.zxing.NotFoundException;
|
|
import com.google.zxing.RXingResult;
|
|
import com.google.zxing.RXingResultMetadataType;
|
|
import com.google.zxing.RXingResultPoint;
|
|
import com.google.zxing.common.BitArray;
|
|
|
|
import java.util.Arrays;
|
|
import java.util.Map;
|
|
|
|
/**
|
|
* <p>Decodes Code 93 barcodes.</p>
|
|
*
|
|
* @author Sean Owen
|
|
* @see Code39Reader
|
|
*/
|
|
public final class Code93Reader extends OneDReader {
|
|
|
|
// Note that 'abcd' are dummy characters in place of control characters.
|
|
static final String ALPHABET_STRING = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-. $/+%abcd*";
|
|
private static final char[] ALPHABET = ALPHABET_STRING.toCharArray();
|
|
|
|
/**
|
|
* These represent the encodings of characters, as patterns of wide and narrow bars.
|
|
* The 9 least-significant bits of each int correspond to the pattern of wide and narrow.
|
|
*/
|
|
static final int[] CHARACTER_ENCODINGS = {
|
|
0x114, 0x148, 0x144, 0x142, 0x128, 0x124, 0x122, 0x150, 0x112, 0x10A, // 0-9
|
|
0x1A8, 0x1A4, 0x1A2, 0x194, 0x192, 0x18A, 0x168, 0x164, 0x162, 0x134, // A-J
|
|
0x11A, 0x158, 0x14C, 0x146, 0x12C, 0x116, 0x1B4, 0x1B2, 0x1AC, 0x1A6, // K-T
|
|
0x196, 0x19A, 0x16C, 0x166, 0x136, 0x13A, // U-Z
|
|
0x12E, 0x1D4, 0x1D2, 0x1CA, 0x16E, 0x176, 0x1AE, // - - %
|
|
0x126, 0x1DA, 0x1D6, 0x132, 0x15E, // Control chars? $-*
|
|
};
|
|
static final int ASTERISK_ENCODING = CHARACTER_ENCODINGS[47];
|
|
|
|
private final StringBuilder decodeRowRXingResult;
|
|
private final int[] counters;
|
|
|
|
public Code93Reader() {
|
|
decodeRowRXingResult = new StringBuilder(20);
|
|
counters = new int[6];
|
|
}
|
|
|
|
@Override
|
|
public RXingResult decodeRow(int rowNumber, BitArray row, Map<DecodeHintType,?> hints)
|
|
throws NotFoundException, ChecksumException, FormatException {
|
|
|
|
int[] start = findAsteriskPattern(row);
|
|
// Read off white space
|
|
int nextStart = row.getNextSet(start[1]);
|
|
int end = row.getSize();
|
|
|
|
int[] theCounters = counters;
|
|
Arrays.fill(theCounters, 0);
|
|
StringBuilder result = decodeRowRXingResult;
|
|
result.setLength(0);
|
|
|
|
char decodedChar;
|
|
int lastStart;
|
|
do {
|
|
recordPattern(row, nextStart, theCounters);
|
|
int pattern = toPattern(theCounters);
|
|
if (pattern < 0) {
|
|
throw NotFoundException.getNotFoundInstance();
|
|
}
|
|
decodedChar = patternToChar(pattern);
|
|
result.append(decodedChar);
|
|
lastStart = nextStart;
|
|
for (int counter : theCounters) {
|
|
nextStart += counter;
|
|
}
|
|
// Read off white space
|
|
nextStart = row.getNextSet(nextStart);
|
|
} while (decodedChar != '*');
|
|
result.deleteCharAt(result.length() - 1); // remove asterisk
|
|
|
|
int lastPatternSize = 0;
|
|
for (int counter : theCounters) {
|
|
lastPatternSize += counter;
|
|
}
|
|
|
|
// Should be at least one more black module
|
|
if (nextStart == end || !row.get(nextStart)) {
|
|
throw NotFoundException.getNotFoundInstance();
|
|
}
|
|
|
|
if (result.length() < 2) {
|
|
// false positive -- need at least 2 checksum digits
|
|
throw NotFoundException.getNotFoundInstance();
|
|
}
|
|
|
|
checkChecksums(result);
|
|
// Remove checksum digits
|
|
result.setLength(result.length() - 2);
|
|
|
|
String resultString = decodeExtended(result);
|
|
|
|
float left = (start[1] + start[0]) / 2.0f;
|
|
float right = lastStart + lastPatternSize / 2.0f;
|
|
|
|
RXingResult resultObject = new RXingResult(
|
|
resultString,
|
|
null,
|
|
new RXingResultPoint[]{
|
|
new RXingResultPoint(left, rowNumber),
|
|
new RXingResultPoint(right, rowNumber)},
|
|
BarcodeFormat.CODE_93);
|
|
resultObject.putMetadata(RXingResultMetadataType.SYMBOLOGY_IDENTIFIER, "]G0");
|
|
return resultObject;
|
|
}
|
|
|
|
private int[] findAsteriskPattern(BitArray row) throws NotFoundException {
|
|
int width = row.getSize();
|
|
int rowOffset = row.getNextSet(0);
|
|
|
|
Arrays.fill(counters, 0);
|
|
int[] theCounters = counters;
|
|
int patternStart = rowOffset;
|
|
boolean isWhite = false;
|
|
int patternLength = theCounters.length;
|
|
|
|
int counterPosition = 0;
|
|
for (int i = rowOffset; i < width; i++) {
|
|
if (row.get(i) != isWhite) {
|
|
theCounters[counterPosition]++;
|
|
} else {
|
|
if (counterPosition == patternLength - 1) {
|
|
if (toPattern(theCounters) == ASTERISK_ENCODING) {
|
|
return new int[]{patternStart, i};
|
|
}
|
|
patternStart += theCounters[0] + theCounters[1];
|
|
System.arraycopy(theCounters, 2, theCounters, 0, counterPosition - 1);
|
|
theCounters[counterPosition - 1] = 0;
|
|
theCounters[counterPosition] = 0;
|
|
counterPosition--;
|
|
} else {
|
|
counterPosition++;
|
|
}
|
|
theCounters[counterPosition] = 1;
|
|
isWhite = !isWhite;
|
|
}
|
|
}
|
|
throw NotFoundException.getNotFoundInstance();
|
|
}
|
|
|
|
private static int toPattern(int[] counters) {
|
|
int sum = 0;
|
|
for (int counter : counters) {
|
|
sum += counter;
|
|
}
|
|
int pattern = 0;
|
|
int max = counters.length;
|
|
for (int i = 0; i < max; i++) {
|
|
int scaled = Math.round(counters[i] * 9.0f / sum);
|
|
if (scaled < 1 || scaled > 4) {
|
|
return -1;
|
|
}
|
|
if ((i & 0x01) == 0) {
|
|
for (int j = 0; j < scaled; j++) {
|
|
pattern = (pattern << 1) | 0x01;
|
|
}
|
|
} else {
|
|
pattern <<= scaled;
|
|
}
|
|
}
|
|
return pattern;
|
|
}
|
|
|
|
private static char patternToChar(int pattern) throws NotFoundException {
|
|
for (int i = 0; i < CHARACTER_ENCODINGS.length; i++) {
|
|
if (CHARACTER_ENCODINGS[i] == pattern) {
|
|
return ALPHABET[i];
|
|
}
|
|
}
|
|
throw NotFoundException.getNotFoundInstance();
|
|
}
|
|
|
|
private static String decodeExtended(CharSequence encoded) throws FormatException {
|
|
int length = encoded.length();
|
|
StringBuilder decoded = new StringBuilder(length);
|
|
for (int i = 0; i < length; i++) {
|
|
char c = encoded.charAt(i);
|
|
if (c >= 'a' && c <= 'd') {
|
|
if (i >= length - 1) {
|
|
throw FormatException.getFormatInstance();
|
|
}
|
|
char next = encoded.charAt(i + 1);
|
|
char decodedChar = '\0';
|
|
switch (c) {
|
|
case 'd':
|
|
// +A to +Z map to a to z
|
|
if (next >= 'A' && next <= 'Z') {
|
|
decodedChar = (char) (next + 32);
|
|
} else {
|
|
throw FormatException.getFormatInstance();
|
|
}
|
|
break;
|
|
case 'a':
|
|
// $A to $Z map to control codes SH to SB
|
|
if (next >= 'A' && next <= 'Z') {
|
|
decodedChar = (char) (next - 64);
|
|
} else {
|
|
throw FormatException.getFormatInstance();
|
|
}
|
|
break;
|
|
case 'b':
|
|
if (next >= 'A' && next <= 'E') {
|
|
// %A to %E map to control codes ESC to USep
|
|
decodedChar = (char) (next - 38);
|
|
} else if (next >= 'F' && next <= 'J') {
|
|
// %F to %J map to ; < = > ?
|
|
decodedChar = (char) (next - 11);
|
|
} else if (next >= 'K' && next <= 'O') {
|
|
// %K to %O map to [ \ ] ^ _
|
|
decodedChar = (char) (next + 16);
|
|
} else if (next >= 'P' && next <= 'T') {
|
|
// %P to %T map to { | } ~ DEL
|
|
decodedChar = (char) (next + 43);
|
|
} else if (next == 'U') {
|
|
// %U map to NUL
|
|
decodedChar = '\0';
|
|
} else if (next == 'V') {
|
|
// %V map to @
|
|
decodedChar = '@';
|
|
} else if (next == 'W') {
|
|
// %W map to `
|
|
decodedChar = '`';
|
|
} else if (next >= 'X' && next <= 'Z') {
|
|
// %X to %Z all map to DEL (127)
|
|
decodedChar = 127;
|
|
} else {
|
|
throw FormatException.getFormatInstance();
|
|
}
|
|
break;
|
|
case 'c':
|
|
// /A to /O map to ! to , and /Z maps to :
|
|
if (next >= 'A' && next <= 'O') {
|
|
decodedChar = (char) (next - 32);
|
|
} else if (next == 'Z') {
|
|
decodedChar = ':';
|
|
} else {
|
|
throw FormatException.getFormatInstance();
|
|
}
|
|
break;
|
|
}
|
|
decoded.append(decodedChar);
|
|
// bump up i again since we read two characters
|
|
i++;
|
|
} else {
|
|
decoded.append(c);
|
|
}
|
|
}
|
|
return decoded.toString();
|
|
}
|
|
|
|
private static void checkChecksums(CharSequence result) throws ChecksumException {
|
|
int length = result.length();
|
|
checkOneChecksum(result, length - 2, 20);
|
|
checkOneChecksum(result, length - 1, 15);
|
|
}
|
|
|
|
private static void checkOneChecksum(CharSequence result, int checkPosition, int weightMax)
|
|
throws ChecksumException {
|
|
int weight = 1;
|
|
int total = 0;
|
|
for (int i = checkPosition - 1; i >= 0; i--) {
|
|
total += weight * ALPHABET_STRING.indexOf(result.charAt(i));
|
|
if (++weight > weightMax) {
|
|
weight = 1;
|
|
}
|
|
}
|
|
if (result.charAt(checkPosition) != ALPHABET[total % 47]) {
|
|
throw ChecksumException.getChecksumInstance();
|
|
}
|
|
}
|
|
|
|
}
|