@zxing/library
Version:
TypeScript port of ZXing multi-format 1D/2D barcode image processing library.
97 lines • 4.42 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 __());
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
var BarcodeFormat_1 = require("../BarcodeFormat");
var UPCEANReader_1 = require("./UPCEANReader");
var NotFoundException_1 = require("../NotFoundException");
/**
* <p>Implements decoding of the EAN-13 format.</p>
*
* @author dswitkin@google.com (Daniel Switkin)
* @author Sean Owen
* @author alasdair@google.com (Alasdair Mackintosh)
*/
var EAN13Reader = /** @class */ (function (_super) {
__extends(EAN13Reader, _super);
function EAN13Reader() {
var _this = _super.call(this) || this;
_this.decodeMiddleCounters = [0, 0, 0, 0];
return _this;
}
EAN13Reader.prototype.decodeMiddle = function (row, startRange, resultString) {
var counters = this.decodeMiddleCounters;
counters[0] = 0;
counters[1] = 0;
counters[2] = 0;
counters[3] = 0;
var end = row.getSize();
var rowOffset = startRange[1];
var lgPatternFound = 0;
for (var x = 0; x < 6 && rowOffset < end; x++) {
var bestMatch = UPCEANReader_1.default.decodeDigit(row, counters, rowOffset, UPCEANReader_1.default.L_AND_G_PATTERNS);
resultString += String.fromCharCode(('0'.charCodeAt(0) + bestMatch % 10));
for (var _i = 0, counters_1 = counters; _i < counters_1.length; _i++) {
var counter = counters_1[_i];
rowOffset += counter;
}
if (bestMatch >= 10) {
lgPatternFound |= 1 << (5 - x);
}
}
resultString = EAN13Reader.determineFirstDigit(resultString, lgPatternFound);
var middleRange = UPCEANReader_1.default.findGuardPattern(row, rowOffset, true, UPCEANReader_1.default.MIDDLE_PATTERN, new Array(UPCEANReader_1.default.MIDDLE_PATTERN.length).fill(0));
rowOffset = middleRange[1];
for (var x = 0; x < 6 && rowOffset < end; x++) {
var bestMatch = UPCEANReader_1.default.decodeDigit(row, counters, rowOffset, UPCEANReader_1.default.L_PATTERNS);
resultString += String.fromCharCode(('0'.charCodeAt(0) + bestMatch));
for (var _a = 0, counters_2 = counters; _a < counters_2.length; _a++) {
var counter = counters_2[_a];
rowOffset += counter;
}
}
return { rowOffset: rowOffset, resultString: resultString };
};
EAN13Reader.prototype.getBarcodeFormat = function () {
return BarcodeFormat_1.default.EAN_13;
};
EAN13Reader.determineFirstDigit = function (resultString, lgPatternFound) {
for (var d = 0; d < 10; d++) {
if (lgPatternFound === this.FIRST_DIGIT_ENCODINGS[d]) {
resultString = String.fromCharCode(('0'.charCodeAt(0) + d)) + resultString;
return resultString;
}
}
throw new NotFoundException_1.default();
};
EAN13Reader.FIRST_DIGIT_ENCODINGS = [0x00, 0x0B, 0x0D, 0xE, 0x13, 0x19, 0x1C, 0x15, 0x16, 0x1A];
return EAN13Reader;
}(UPCEANReader_1.default));
exports.default = EAN13Reader;
//# sourceMappingURL=EAN13Reader.js.map