@zxing/library
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TypeScript port of ZXing multi-format 1D/2D barcode image processing library.
518 lines (517 loc) • 24.1 kB
JavaScript
/*
* Copyright 2008 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.
*/
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
/*namespace com.google.zxing.oned {*/
import BarcodeFormat from '../BarcodeFormat';
import ChecksumException from '../ChecksumException';
import DecodeHintType from '../DecodeHintType';
import FormatException from '../FormatException';
import NotFoundException from '../NotFoundException';
// import Reader from '../Reader';
import Result from '../Result';
// import ResultMetadataType from '../ResultMetadataType';
import ResultPoint from '../ResultPoint';
import OneDReader from './OneDReader';
/**
* <p>Decodes Code 128 barcodes.</p>
*
* @author Sean Owen
*/
var Code128Reader = /** @class */ (function (_super) {
__extends(Code128Reader, _super);
function Code128Reader() {
return _super !== null && _super.apply(this, arguments) || this;
}
Code128Reader.findStartPattern = function (row) {
var width = row.getSize();
var rowOffset = row.getNextSet(0);
var counterPosition = 0;
var counters = Int32Array.from([0, 0, 0, 0, 0, 0]);
var patternStart = rowOffset;
var isWhite = false;
var patternLength = 6;
for (var i = rowOffset; i < width; i++) {
if (row.get(i) !== isWhite) {
counters[counterPosition]++;
}
else {
if (counterPosition === (patternLength - 1)) {
var bestVariance = Code128Reader.MAX_AVG_VARIANCE;
var bestMatch = -1;
for (var startCode = Code128Reader.CODE_START_A; startCode <= Code128Reader.CODE_START_C; startCode++) {
var variance = OneDReader.patternMatchVariance(counters, Code128Reader.CODE_PATTERNS[startCode], Code128Reader.MAX_INDIVIDUAL_VARIANCE);
if (variance < bestVariance) {
bestVariance = variance;
bestMatch = startCode;
}
}
// Look for whitespace before start pattern, >= 50% of width of start pattern
if (bestMatch >= 0 &&
row.isRange(Math.max(0, patternStart - (i - patternStart) / 2), patternStart, false)) {
return Int32Array.from([patternStart, i, bestMatch]);
}
patternStart += counters[0] + counters[1];
counters = counters.slice(2, counters.length);
counters[counterPosition - 1] = 0;
counters[counterPosition] = 0;
counterPosition--;
}
else {
counterPosition++;
}
counters[counterPosition] = 1;
isWhite = !isWhite;
}
}
throw new NotFoundException();
};
Code128Reader.decodeCode = function (row, counters, rowOffset) {
OneDReader.recordPattern(row, rowOffset, counters);
var bestVariance = Code128Reader.MAX_AVG_VARIANCE; // worst variance we'll accept
var bestMatch = -1;
for (var d = 0; d < Code128Reader.CODE_PATTERNS.length; d++) {
var pattern = Code128Reader.CODE_PATTERNS[d];
var variance = this.patternMatchVariance(counters, pattern, Code128Reader.MAX_INDIVIDUAL_VARIANCE);
if (variance < bestVariance) {
bestVariance = variance;
bestMatch = d;
}
}
// TODO We're overlooking the fact that the STOP pattern has 7 values, not 6.
if (bestMatch >= 0) {
return bestMatch;
}
else {
throw new NotFoundException();
}
};
Code128Reader.prototype.decodeRow = function (rowNumber, row, hints) {
var convertFNC1 = hints && (hints.get(DecodeHintType.ASSUME_GS1) === true);
var startPatternInfo = Code128Reader.findStartPattern(row);
var startCode = startPatternInfo[2];
var currentRawCodesIndex = 0;
var rawCodes = new Uint8Array(20);
rawCodes[currentRawCodesIndex++] = startCode;
var codeSet;
switch (startCode) {
case Code128Reader.CODE_START_A:
codeSet = Code128Reader.CODE_CODE_A;
break;
case Code128Reader.CODE_START_B:
codeSet = Code128Reader.CODE_CODE_B;
break;
case Code128Reader.CODE_START_C:
codeSet = Code128Reader.CODE_CODE_C;
break;
default:
throw new FormatException();
}
var done = false;
var isNextShifted = false;
var result = '';
var lastStart = startPatternInfo[0];
var nextStart = startPatternInfo[1];
var counters = Int32Array.from([0, 0, 0, 0, 0, 0]);
var lastCode = 0;
var code = 0;
var checksumTotal = startCode;
var multiplier = 0;
var lastCharacterWasPrintable = true;
var upperMode = false;
var shiftUpperMode = false;
while (!done) {
var unshift = isNextShifted;
isNextShifted = false;
// Save off last code
lastCode = code;
// Decode another code from image
code = Code128Reader.decodeCode(row, counters, nextStart);
rawCodes[currentRawCodesIndex++] = code;
// Remember whether the last code was printable or not (excluding CODE_STOP)
if (code !== Code128Reader.CODE_STOP) {
lastCharacterWasPrintable = true;
}
// Add to checksum computation (if not CODE_STOP of course)
if (code !== Code128Reader.CODE_STOP) {
multiplier++;
checksumTotal += multiplier * code;
}
// Advance to where the next code will to start
lastStart = nextStart;
nextStart += counters.reduce(function (previous, current) { return previous + current; }, 0);
// Take care of illegal start codes
switch (code) {
case Code128Reader.CODE_START_A:
case Code128Reader.CODE_START_B:
case Code128Reader.CODE_START_C:
throw new FormatException();
}
switch (codeSet) {
case Code128Reader.CODE_CODE_A:
if (code < 64) {
if (shiftUpperMode === upperMode) {
result += String.fromCharCode((' '.charCodeAt(0) + code));
}
else {
result += String.fromCharCode((' '.charCodeAt(0) + code + 128));
}
shiftUpperMode = false;
}
else if (code < 96) {
if (shiftUpperMode === upperMode) {
result += String.fromCharCode((code - 64));
}
else {
result += String.fromCharCode((code + 64));
}
shiftUpperMode = false;
}
else {
// Don't let CODE_STOP, which always appears, affect whether whether we think the last
// code was printable or not.
if (code !== Code128Reader.CODE_STOP) {
lastCharacterWasPrintable = false;
}
switch (code) {
case Code128Reader.CODE_FNC_1:
if (convertFNC1) {
if (result.length === 0) {
// GS1 specification 5.4.3.7. and 5.4.6.4. If the first char after the start code
// is FNC1 then this is GS1-128. We add the symbology identifier.
result += ']C1';
}
else {
// GS1 specification 5.4.7.5. Every subsequent FNC1 is returned as ASCII 29 (GS)
result += String.fromCharCode(29);
}
}
break;
case Code128Reader.CODE_FNC_2:
case Code128Reader.CODE_FNC_3:
// do nothing?
break;
case Code128Reader.CODE_FNC_4_A:
if (!upperMode && shiftUpperMode) {
upperMode = true;
shiftUpperMode = false;
}
else if (upperMode && shiftUpperMode) {
upperMode = false;
shiftUpperMode = false;
}
else {
shiftUpperMode = true;
}
break;
case Code128Reader.CODE_SHIFT:
isNextShifted = true;
codeSet = Code128Reader.CODE_CODE_B;
break;
case Code128Reader.CODE_CODE_B:
codeSet = Code128Reader.CODE_CODE_B;
break;
case Code128Reader.CODE_CODE_C:
codeSet = Code128Reader.CODE_CODE_C;
break;
case Code128Reader.CODE_STOP:
done = true;
break;
}
}
break;
case Code128Reader.CODE_CODE_B:
if (code < 96) {
if (shiftUpperMode === upperMode) {
result += String.fromCharCode((' '.charCodeAt(0) + code));
}
else {
result += String.fromCharCode((' '.charCodeAt(0) + code + 128));
}
shiftUpperMode = false;
}
else {
if (code !== Code128Reader.CODE_STOP) {
lastCharacterWasPrintable = false;
}
switch (code) {
case Code128Reader.CODE_FNC_1:
if (convertFNC1) {
if (result.length === 0) {
// GS1 specification 5.4.3.7. and 5.4.6.4. If the first char after the start code
// is FNC1 then this is GS1-128. We add the symbology identifier.
result += ']C1';
}
else {
// GS1 specification 5.4.7.5. Every subsequent FNC1 is returned as ASCII 29 (GS)
result += String.fromCharCode(29);
}
}
break;
case Code128Reader.CODE_FNC_2:
case Code128Reader.CODE_FNC_3:
// do nothing?
break;
case Code128Reader.CODE_FNC_4_B:
if (!upperMode && shiftUpperMode) {
upperMode = true;
shiftUpperMode = false;
}
else if (upperMode && shiftUpperMode) {
upperMode = false;
shiftUpperMode = false;
}
else {
shiftUpperMode = true;
}
break;
case Code128Reader.CODE_SHIFT:
isNextShifted = true;
codeSet = Code128Reader.CODE_CODE_A;
break;
case Code128Reader.CODE_CODE_A:
codeSet = Code128Reader.CODE_CODE_A;
break;
case Code128Reader.CODE_CODE_C:
codeSet = Code128Reader.CODE_CODE_C;
break;
case Code128Reader.CODE_STOP:
done = true;
break;
}
}
break;
case Code128Reader.CODE_CODE_C:
if (code < 100) {
if (code < 10) {
result += '0';
}
result += code;
}
else {
if (code !== Code128Reader.CODE_STOP) {
lastCharacterWasPrintable = false;
}
switch (code) {
case Code128Reader.CODE_FNC_1:
if (convertFNC1) {
if (result.length === 0) {
// GS1 specification 5.4.3.7. and 5.4.6.4. If the first char after the start code
// is FNC1 then this is GS1-128. We add the symbology identifier.
result += ']C1';
}
else {
// GS1 specification 5.4.7.5. Every subsequent FNC1 is returned as ASCII 29 (GS)
result += String.fromCharCode(29);
}
}
break;
case Code128Reader.CODE_CODE_A:
codeSet = Code128Reader.CODE_CODE_A;
break;
case Code128Reader.CODE_CODE_B:
codeSet = Code128Reader.CODE_CODE_B;
break;
case Code128Reader.CODE_STOP:
done = true;
break;
}
}
break;
}
// Unshift back to another code set if we were shifted
if (unshift) {
codeSet = codeSet === Code128Reader.CODE_CODE_A ? Code128Reader.CODE_CODE_B : Code128Reader.CODE_CODE_A;
}
}
var lastPatternSize = nextStart - lastStart;
// Check for ample whitespace following pattern, but, to do this we first need to remember that
// we fudged decoding CODE_STOP since it actually has 7 bars, not 6. There is a black bar left
// to read off. Would be slightly better to properly read. Here we just skip it:
nextStart = row.getNextUnset(nextStart);
if (!row.isRange(nextStart, Math.min(row.getSize(), nextStart + (nextStart - lastStart) / 2), false)) {
throw new NotFoundException();
}
// Pull out from sum the value of the penultimate check code
checksumTotal -= multiplier * lastCode;
// lastCode is the checksum then:
if (checksumTotal % 103 !== lastCode) {
throw new ChecksumException();
}
// Need to pull out the check digits from string
var resultLength = result.length;
if (resultLength === 0) {
// false positive
throw new NotFoundException();
}
// Only bother if the result had at least one character, and if the checksum digit happened to
// be a printable character. If it was just interpreted as a control code, nothing to remove.
if (resultLength > 0 && lastCharacterWasPrintable) {
if (codeSet === Code128Reader.CODE_CODE_C) {
result = result.substring(0, resultLength - 2);
}
else {
result = result.substring(0, resultLength - 1);
}
}
var left = (startPatternInfo[1] + startPatternInfo[0]) / 2.0;
var right = lastStart + lastPatternSize / 2.0;
var rawCodesSize = rawCodes.length;
var rawBytes = new Uint8Array(rawCodesSize);
for (var i = 0; i < rawCodesSize; i++) {
rawBytes[i] = rawCodes[i];
}
var points = [new ResultPoint(left, rowNumber), new ResultPoint(right, rowNumber)];
return new Result(result, rawBytes, 0, points, BarcodeFormat.CODE_128, new Date().getTime());
};
Code128Reader.CODE_PATTERNS = [
Int32Array.from([2, 1, 2, 2, 2, 2]),
Int32Array.from([2, 2, 2, 1, 2, 2]),
Int32Array.from([2, 2, 2, 2, 2, 1]),
Int32Array.from([1, 2, 1, 2, 2, 3]),
Int32Array.from([1, 2, 1, 3, 2, 2]),
Int32Array.from([1, 3, 1, 2, 2, 2]),
Int32Array.from([1, 2, 2, 2, 1, 3]),
Int32Array.from([1, 2, 2, 3, 1, 2]),
Int32Array.from([1, 3, 2, 2, 1, 2]),
Int32Array.from([2, 2, 1, 2, 1, 3]),
Int32Array.from([2, 2, 1, 3, 1, 2]),
Int32Array.from([2, 3, 1, 2, 1, 2]),
Int32Array.from([1, 1, 2, 2, 3, 2]),
Int32Array.from([1, 2, 2, 1, 3, 2]),
Int32Array.from([1, 2, 2, 2, 3, 1]),
Int32Array.from([1, 1, 3, 2, 2, 2]),
Int32Array.from([1, 2, 3, 1, 2, 2]),
Int32Array.from([1, 2, 3, 2, 2, 1]),
Int32Array.from([2, 2, 3, 2, 1, 1]),
Int32Array.from([2, 2, 1, 1, 3, 2]),
Int32Array.from([2, 2, 1, 2, 3, 1]),
Int32Array.from([2, 1, 3, 2, 1, 2]),
Int32Array.from([2, 2, 3, 1, 1, 2]),
Int32Array.from([3, 1, 2, 1, 3, 1]),
Int32Array.from([3, 1, 1, 2, 2, 2]),
Int32Array.from([3, 2, 1, 1, 2, 2]),
Int32Array.from([3, 2, 1, 2, 2, 1]),
Int32Array.from([3, 1, 2, 2, 1, 2]),
Int32Array.from([3, 2, 2, 1, 1, 2]),
Int32Array.from([3, 2, 2, 2, 1, 1]),
Int32Array.from([2, 1, 2, 1, 2, 3]),
Int32Array.from([2, 1, 2, 3, 2, 1]),
Int32Array.from([2, 3, 2, 1, 2, 1]),
Int32Array.from([1, 1, 1, 3, 2, 3]),
Int32Array.from([1, 3, 1, 1, 2, 3]),
Int32Array.from([1, 3, 1, 3, 2, 1]),
Int32Array.from([1, 1, 2, 3, 1, 3]),
Int32Array.from([1, 3, 2, 1, 1, 3]),
Int32Array.from([1, 3, 2, 3, 1, 1]),
Int32Array.from([2, 1, 1, 3, 1, 3]),
Int32Array.from([2, 3, 1, 1, 1, 3]),
Int32Array.from([2, 3, 1, 3, 1, 1]),
Int32Array.from([1, 1, 2, 1, 3, 3]),
Int32Array.from([1, 1, 2, 3, 3, 1]),
Int32Array.from([1, 3, 2, 1, 3, 1]),
Int32Array.from([1, 1, 3, 1, 2, 3]),
Int32Array.from([1, 1, 3, 3, 2, 1]),
Int32Array.from([1, 3, 3, 1, 2, 1]),
Int32Array.from([3, 1, 3, 1, 2, 1]),
Int32Array.from([2, 1, 1, 3, 3, 1]),
Int32Array.from([2, 3, 1, 1, 3, 1]),
Int32Array.from([2, 1, 3, 1, 1, 3]),
Int32Array.from([2, 1, 3, 3, 1, 1]),
Int32Array.from([2, 1, 3, 1, 3, 1]),
Int32Array.from([3, 1, 1, 1, 2, 3]),
Int32Array.from([3, 1, 1, 3, 2, 1]),
Int32Array.from([3, 3, 1, 1, 2, 1]),
Int32Array.from([3, 1, 2, 1, 1, 3]),
Int32Array.from([3, 1, 2, 3, 1, 1]),
Int32Array.from([3, 3, 2, 1, 1, 1]),
Int32Array.from([3, 1, 4, 1, 1, 1]),
Int32Array.from([2, 2, 1, 4, 1, 1]),
Int32Array.from([4, 3, 1, 1, 1, 1]),
Int32Array.from([1, 1, 1, 2, 2, 4]),
Int32Array.from([1, 1, 1, 4, 2, 2]),
Int32Array.from([1, 2, 1, 1, 2, 4]),
Int32Array.from([1, 2, 1, 4, 2, 1]),
Int32Array.from([1, 4, 1, 1, 2, 2]),
Int32Array.from([1, 4, 1, 2, 2, 1]),
Int32Array.from([1, 1, 2, 2, 1, 4]),
Int32Array.from([1, 1, 2, 4, 1, 2]),
Int32Array.from([1, 2, 2, 1, 1, 4]),
Int32Array.from([1, 2, 2, 4, 1, 1]),
Int32Array.from([1, 4, 2, 1, 1, 2]),
Int32Array.from([1, 4, 2, 2, 1, 1]),
Int32Array.from([2, 4, 1, 2, 1, 1]),
Int32Array.from([2, 2, 1, 1, 1, 4]),
Int32Array.from([4, 1, 3, 1, 1, 1]),
Int32Array.from([2, 4, 1, 1, 1, 2]),
Int32Array.from([1, 3, 4, 1, 1, 1]),
Int32Array.from([1, 1, 1, 2, 4, 2]),
Int32Array.from([1, 2, 1, 1, 4, 2]),
Int32Array.from([1, 2, 1, 2, 4, 1]),
Int32Array.from([1, 1, 4, 2, 1, 2]),
Int32Array.from([1, 2, 4, 1, 1, 2]),
Int32Array.from([1, 2, 4, 2, 1, 1]),
Int32Array.from([4, 1, 1, 2, 1, 2]),
Int32Array.from([4, 2, 1, 1, 1, 2]),
Int32Array.from([4, 2, 1, 2, 1, 1]),
Int32Array.from([2, 1, 2, 1, 4, 1]),
Int32Array.from([2, 1, 4, 1, 2, 1]),
Int32Array.from([4, 1, 2, 1, 2, 1]),
Int32Array.from([1, 1, 1, 1, 4, 3]),
Int32Array.from([1, 1, 1, 3, 4, 1]),
Int32Array.from([1, 3, 1, 1, 4, 1]),
Int32Array.from([1, 1, 4, 1, 1, 3]),
Int32Array.from([1, 1, 4, 3, 1, 1]),
Int32Array.from([4, 1, 1, 1, 1, 3]),
Int32Array.from([4, 1, 1, 3, 1, 1]),
Int32Array.from([1, 1, 3, 1, 4, 1]),
Int32Array.from([1, 1, 4, 1, 3, 1]),
Int32Array.from([3, 1, 1, 1, 4, 1]),
Int32Array.from([4, 1, 1, 1, 3, 1]),
Int32Array.from([2, 1, 1, 4, 1, 2]),
Int32Array.from([2, 1, 1, 2, 1, 4]),
Int32Array.from([2, 1, 1, 2, 3, 2]),
Int32Array.from([2, 3, 3, 1, 1, 1, 2]),
];
Code128Reader.MAX_AVG_VARIANCE = 0.25;
Code128Reader.MAX_INDIVIDUAL_VARIANCE = 0.7;
Code128Reader.CODE_SHIFT = 98;
Code128Reader.CODE_CODE_C = 99;
Code128Reader.CODE_CODE_B = 100;
Code128Reader.CODE_CODE_A = 101;
Code128Reader.CODE_FNC_1 = 102;
Code128Reader.CODE_FNC_2 = 97;
Code128Reader.CODE_FNC_3 = 96;
Code128Reader.CODE_FNC_4_A = 101;
Code128Reader.CODE_FNC_4_B = 100;
Code128Reader.CODE_START_A = 103;
Code128Reader.CODE_START_B = 104;
Code128Reader.CODE_START_C = 105;
Code128Reader.CODE_STOP = 106;
return Code128Reader;
}(OneDReader));
export default Code128Reader;