@zxing/library
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TypeScript port of ZXing multi-format 1D/2D barcode image processing library.
254 lines (253 loc) • 11.8 kB
JavaScript
/*
* Copyright 2013 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.
*/
// import com.google.zxing.pdf417.PDF417Common;
import PDF417Common from '../PDF417Common';
import BarcodeMetadata from './BarcodeMetadata';
import DetectionResultColumn from './DetectionResultColumn';
import BarcodeValue from './BarcodeValue';
/**
* @author Guenther Grau
*/
export default /*final*/ class DetectionResultRowIndicatorColumn extends DetectionResultColumn {
constructor(boundingBox, isLeft) {
super(boundingBox);
this._isLeft = isLeft;
}
setRowNumbers() {
for (let codeword /*Codeword*/ of this.getCodewords()) {
if (codeword != null) {
codeword.setRowNumberAsRowIndicatorColumn();
}
}
}
// TODO implement properly
// TODO maybe we should add missing codewords to store the correct row number to make
// finding row numbers for other columns easier
// use row height count to make detection of invalid row numbers more reliable
adjustCompleteIndicatorColumnRowNumbers(barcodeMetadata) {
let codewords = this.getCodewords();
this.setRowNumbers();
this.removeIncorrectCodewords(codewords, barcodeMetadata);
let boundingBox = this.getBoundingBox();
let top = this._isLeft ? boundingBox.getTopLeft() : boundingBox.getTopRight();
let bottom = this._isLeft ? boundingBox.getBottomLeft() : boundingBox.getBottomRight();
let firstRow = this.imageRowToCodewordIndex(Math.trunc(top.getY()));
let lastRow = this.imageRowToCodewordIndex(Math.trunc(bottom.getY()));
// We need to be careful using the average row height. Barcode could be skewed so that we have smaller and
// taller rows
// float averageRowHeight = (lastRow - firstRow) / /*(float)*/ barcodeMetadata.getRowCount();
let barcodeRow = -1;
let maxRowHeight = 1;
let currentRowHeight = 0;
for (let codewordsRow /*int*/ = firstRow; codewordsRow < lastRow; codewordsRow++) {
if (codewords[codewordsRow] == null) {
continue;
}
let codeword = codewords[codewordsRow];
// float expectedRowNumber = (codewordsRow - firstRow) / averageRowHeight;
// if (Math.abs(codeword.getRowNumber() - expectedRowNumber) > 2) {
// SimpleLog.log(LEVEL.WARNING,
// "Removing codeword, rowNumberSkew too high, codeword[" + codewordsRow + "]: Expected Row: " +
// expectedRowNumber + ", RealRow: " + codeword.getRowNumber() + ", value: " + codeword.getValue());
// codewords[codewordsRow] = null;
// }
let rowDifference = codeword.getRowNumber() - barcodeRow;
// TODO improve handling with case where first row indicator doesn't start with 0
if (rowDifference === 0) {
currentRowHeight++;
}
else if (rowDifference === 1) {
maxRowHeight = Math.max(maxRowHeight, currentRowHeight);
currentRowHeight = 1;
barcodeRow = codeword.getRowNumber();
}
else if (rowDifference < 0 ||
codeword.getRowNumber() >= barcodeMetadata.getRowCount() ||
rowDifference > codewordsRow) {
codewords[codewordsRow] = null;
}
else {
let checkedRows;
if (maxRowHeight > 2) {
checkedRows = (maxRowHeight - 2) * rowDifference;
}
else {
checkedRows = rowDifference;
}
let closePreviousCodewordFound = checkedRows >= codewordsRow;
for (let i /*int*/ = 1; i <= checkedRows && !closePreviousCodewordFound; i++) {
// there must be (height * rowDifference) number of codewords missing. For now we assume height = 1.
// This should hopefully get rid of most problems already.
closePreviousCodewordFound = codewords[codewordsRow - i] != null;
}
if (closePreviousCodewordFound) {
codewords[codewordsRow] = null;
}
else {
barcodeRow = codeword.getRowNumber();
currentRowHeight = 1;
}
}
}
// return (int) (averageRowHeight + 0.5);
}
getRowHeights() {
let barcodeMetadata = this.getBarcodeMetadata();
if (barcodeMetadata == null) {
return null;
}
this.adjustIncompleteIndicatorColumnRowNumbers(barcodeMetadata);
let result = new Int32Array(barcodeMetadata.getRowCount());
for (let codeword /*Codeword*/ of this.getCodewords()) {
if (codeword != null) {
let rowNumber = codeword.getRowNumber();
if (rowNumber >= result.length) {
// We have more rows than the barcode metadata allows for, ignore them.
continue;
}
result[rowNumber]++;
} // else throw exception?
}
return result;
}
// TODO maybe we should add missing codewords to store the correct row number to make
// finding row numbers for other columns easier
// use row height count to make detection of invalid row numbers more reliable
adjustIncompleteIndicatorColumnRowNumbers(barcodeMetadata) {
let boundingBox = this.getBoundingBox();
let top = this._isLeft ? boundingBox.getTopLeft() : boundingBox.getTopRight();
let bottom = this._isLeft ? boundingBox.getBottomLeft() : boundingBox.getBottomRight();
let firstRow = this.imageRowToCodewordIndex(Math.trunc(top.getY()));
let lastRow = this.imageRowToCodewordIndex(Math.trunc(bottom.getY()));
// float averageRowHeight = (lastRow - firstRow) / /*(float)*/ barcodeMetadata.getRowCount();
let codewords = this.getCodewords();
let barcodeRow = -1;
let maxRowHeight = 1;
let currentRowHeight = 0;
for (let codewordsRow /*int*/ = firstRow; codewordsRow < lastRow; codewordsRow++) {
if (codewords[codewordsRow] == null) {
continue;
}
let codeword = codewords[codewordsRow];
codeword.setRowNumberAsRowIndicatorColumn();
let rowDifference = codeword.getRowNumber() - barcodeRow;
// TODO improve handling with case where first row indicator doesn't start with 0
if (rowDifference === 0) {
currentRowHeight++;
}
else if (rowDifference === 1) {
maxRowHeight = Math.max(maxRowHeight, currentRowHeight);
currentRowHeight = 1;
barcodeRow = codeword.getRowNumber();
}
else if (codeword.getRowNumber() >= barcodeMetadata.getRowCount()) {
codewords[codewordsRow] = null;
}
else {
barcodeRow = codeword.getRowNumber();
currentRowHeight = 1;
}
}
// return (int) (averageRowHeight + 0.5);
}
getBarcodeMetadata() {
let codewords = this.getCodewords();
let barcodeColumnCount = new BarcodeValue();
let barcodeRowCountUpperPart = new BarcodeValue();
let barcodeRowCountLowerPart = new BarcodeValue();
let barcodeECLevel = new BarcodeValue();
for (let codeword /*Codeword*/ of codewords) {
if (codeword == null) {
continue;
}
codeword.setRowNumberAsRowIndicatorColumn();
let rowIndicatorValue = codeword.getValue() % 30;
let codewordRowNumber = codeword.getRowNumber();
if (!this._isLeft) {
codewordRowNumber += 2;
}
switch (codewordRowNumber % 3) {
case 0:
barcodeRowCountUpperPart.setValue(rowIndicatorValue * 3 + 1);
break;
case 1:
barcodeECLevel.setValue(rowIndicatorValue / 3);
barcodeRowCountLowerPart.setValue(rowIndicatorValue % 3);
break;
case 2:
barcodeColumnCount.setValue(rowIndicatorValue + 1);
break;
}
}
// Maybe we should check if we have ambiguous values?
if ((barcodeColumnCount.getValue().length === 0) ||
(barcodeRowCountUpperPart.getValue().length === 0) ||
(barcodeRowCountLowerPart.getValue().length === 0) ||
(barcodeECLevel.getValue().length === 0) ||
barcodeColumnCount.getValue()[0] < 1 ||
barcodeRowCountUpperPart.getValue()[0] + barcodeRowCountLowerPart.getValue()[0] < PDF417Common.MIN_ROWS_IN_BARCODE ||
barcodeRowCountUpperPart.getValue()[0] + barcodeRowCountLowerPart.getValue()[0] > PDF417Common.MAX_ROWS_IN_BARCODE) {
return null;
}
let barcodeMetadata = new BarcodeMetadata(barcodeColumnCount.getValue()[0], barcodeRowCountUpperPart.getValue()[0], barcodeRowCountLowerPart.getValue()[0], barcodeECLevel.getValue()[0]);
this.removeIncorrectCodewords(codewords, barcodeMetadata);
return barcodeMetadata;
}
removeIncorrectCodewords(codewords, barcodeMetadata) {
// Remove codewords which do not match the metadata
// TODO Maybe we should keep the incorrect codewords for the start and end positions?
for (let codewordRow /*int*/ = 0; codewordRow < codewords.length; codewordRow++) {
let codeword = codewords[codewordRow];
if (codewords[codewordRow] == null) {
continue;
}
let rowIndicatorValue = codeword.getValue() % 30;
let codewordRowNumber = codeword.getRowNumber();
if (codewordRowNumber > barcodeMetadata.getRowCount()) {
codewords[codewordRow] = null;
continue;
}
if (!this._isLeft) {
codewordRowNumber += 2;
}
switch (codewordRowNumber % 3) {
case 0:
if (rowIndicatorValue * 3 + 1 !== barcodeMetadata.getRowCountUpperPart()) {
codewords[codewordRow] = null;
}
break;
case 1:
if (Math.trunc(rowIndicatorValue / 3) !== barcodeMetadata.getErrorCorrectionLevel() ||
rowIndicatorValue % 3 !== barcodeMetadata.getRowCountLowerPart()) {
codewords[codewordRow] = null;
}
break;
case 2:
if (rowIndicatorValue + 1 !== barcodeMetadata.getColumnCount()) {
codewords[codewordRow] = null;
}
break;
}
}
}
isLeft() {
return this._isLeft;
}
// @Override
toString() {
return 'IsLeft: ' + this._isLeft + '\n' + super.toString();
}
}