"use strict";
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/*
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* Copyright 2007 ZXing authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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var __values = (this && this.__values) || function(o) {
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var s = typeof Symbol === "function" && Symbol.iterator, m = s && o[s], i = 0;
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if (m) return m.call(o);
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if (o && typeof o.length === "number") return {
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next: function () {
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if (o && i >= o.length) o = void 0;
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return { value: o && o[i++], done: !o };
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}
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};
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throw new TypeError(s ? "Object is not iterable." : "Symbol.iterator is not defined.");
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};
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Object.defineProperty(exports, "__esModule", { value: true });
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var AlignmentPattern_1 = require("./AlignmentPattern");
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var NotFoundException_1 = require("../../NotFoundException");
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/*import java.util.ArrayList;*/
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/*import java.util.List;*/
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/**
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* <p>This class attempts to find alignment patterns in a QR Code. Alignment patterns look like finder
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* patterns but are smaller and appear at regular intervals throughout the image.</p>
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*
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* <p>At the moment this only looks for the bottom-right alignment pattern.</p>
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*
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* <p>This is mostly a simplified copy of {@link FinderPatternFinder}. It is copied,
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* pasted and stripped down here for maximum performance but does unfortunately duplicate
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* some code.</p>
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*
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* <p>This class is thread-safe but not reentrant. Each thread must allocate its own object.</p>
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*
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* @author Sean Owen
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*/
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var AlignmentPatternFinder = /** @class */ (function () {
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/**
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* <p>Creates a finder that will look in a portion of the whole image.</p>
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*
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* @param image image to search
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* @param startX left column from which to start searching
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* @param startY top row from which to start searching
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* @param width width of region to search
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* @param height height of region to search
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* @param moduleSize estimated module size so far
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*/
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function AlignmentPatternFinder(image, startX /*int*/, startY /*int*/, width /*int*/, height /*int*/, moduleSize /*float*/, resultPointCallback) {
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this.image = image;
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this.startX = startX;
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this.startY = startY;
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this.width = width;
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this.height = height;
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this.moduleSize = moduleSize;
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this.resultPointCallback = resultPointCallback;
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this.possibleCenters = []; // new Array<any>(5))
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// TYPESCRIPTPORT: array initialization without size as the length is checked below
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this.crossCheckStateCount = new Int32Array(3);
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}
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/**
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* <p>This method attempts to find the bottom-right alignment pattern in the image. It is a bit messy since
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* it's pretty performance-critical and so is written to be fast foremost.</p>
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*
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* @return {@link AlignmentPattern} if found
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* @throws NotFoundException if not found
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*/
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AlignmentPatternFinder.prototype.find = function () {
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var startX = this.startX;
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var height = this.height;
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var width = this.width;
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var maxJ = startX + width;
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var middleI = this.startY + (height / 2);
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// We are looking for black/white/black modules in 1:1:1 ratio
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// this tracks the number of black/white/black modules seen so far
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var stateCount = new Int32Array(3);
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var image = this.image;
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for (var iGen = 0; iGen < height; iGen++) {
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// Search from middle outwards
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var i = middleI + ((iGen & 0x01) === 0 ? Math.floor((iGen + 1) / 2) : -Math.floor((iGen + 1) / 2));
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stateCount[0] = 0;
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stateCount[1] = 0;
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stateCount[2] = 0;
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var j = startX;
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// Burn off leading white pixels before anything else; if we start in the middle of
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// a white run, it doesn't make sense to count its length, since we don't know if the
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// white run continued to the left of the start point
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while (j < maxJ && !image.get(j, i)) {
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j++;
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}
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var currentState = 0;
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while (j < maxJ) {
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if (image.get(j, i)) {
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// Black pixel
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if (currentState === 1) { // Counting black pixels
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stateCount[1]++;
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}
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else { // Counting white pixels
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if (currentState === 2) { // A winner?
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if (this.foundPatternCross(stateCount)) { // Yes
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var confirmed = this.handlePossibleCenter(stateCount, i, j);
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if (confirmed !== null) {
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return confirmed;
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}
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}
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stateCount[0] = stateCount[2];
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stateCount[1] = 1;
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stateCount[2] = 0;
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currentState = 1;
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}
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else {
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stateCount[++currentState]++;
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}
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}
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}
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else { // White pixel
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if (currentState === 1) { // Counting black pixels
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currentState++;
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}
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stateCount[currentState]++;
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}
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j++;
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}
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if (this.foundPatternCross(stateCount)) {
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var confirmed = this.handlePossibleCenter(stateCount, i, maxJ);
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if (confirmed !== null) {
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return confirmed;
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}
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}
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}
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// Hmm, nothing we saw was observed and confirmed twice. If we had
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// any guess at all, return it.
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if (this.possibleCenters.length !== 0) {
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return this.possibleCenters[0];
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}
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throw new NotFoundException_1.default();
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};
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/**
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* Given a count of black/white/black pixels just seen and an end position,
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* figures the location of the center of this black/white/black run.
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*/
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AlignmentPatternFinder.centerFromEnd = function (stateCount, end /*int*/) {
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return (end - stateCount[2]) - stateCount[1] / 2.0;
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};
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/**
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* @param stateCount count of black/white/black pixels just read
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* @return true iff the proportions of the counts is close enough to the 1/1/1 ratios
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* used by alignment patterns to be considered a match
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*/
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AlignmentPatternFinder.prototype.foundPatternCross = function (stateCount) {
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var moduleSize = this.moduleSize;
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var maxVariance = moduleSize / 2.0;
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for (var i = 0; i < 3; i++) {
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if (Math.abs(moduleSize - stateCount[i]) >= maxVariance) {
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return false;
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}
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}
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return true;
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};
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/**
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* <p>After a horizontal scan finds a potential alignment pattern, this method
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* "cross-checks" by scanning down vertically through the center of the possible
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* alignment pattern to see if the same proportion is detected.</p>
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*
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* @param startI row where an alignment pattern was detected
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* @param centerJ center of the section that appears to cross an alignment pattern
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* @param maxCount maximum reasonable number of modules that should be
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* observed in any reading state, based on the results of the horizontal scan
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* @return vertical center of alignment pattern, or {@link Float#NaN} if not found
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*/
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AlignmentPatternFinder.prototype.crossCheckVertical = function (startI /*int*/, centerJ /*int*/, maxCount /*int*/, originalStateCountTotal /*int*/) {
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var image = this.image;
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var maxI = image.getHeight();
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var stateCount = this.crossCheckStateCount;
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stateCount[0] = 0;
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stateCount[1] = 0;
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stateCount[2] = 0;
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// Start counting up from center
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var i = startI;
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while (i >= 0 && image.get(centerJ, i) && stateCount[1] <= maxCount) {
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stateCount[1]++;
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i--;
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}
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// If already too many modules in this state or ran off the edge:
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if (i < 0 || stateCount[1] > maxCount) {
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return NaN;
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}
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while (i >= 0 && !image.get(centerJ, i) && stateCount[0] <= maxCount) {
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stateCount[0]++;
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i--;
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}
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if (stateCount[0] > maxCount) {
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return NaN;
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}
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// Now also count down from center
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i = startI + 1;
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while (i < maxI && image.get(centerJ, i) && stateCount[1] <= maxCount) {
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stateCount[1]++;
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i++;
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}
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if (i === maxI || stateCount[1] > maxCount) {
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return NaN;
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}
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while (i < maxI && !image.get(centerJ, i) && stateCount[2] <= maxCount) {
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stateCount[2]++;
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i++;
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}
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if (stateCount[2] > maxCount) {
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return NaN;
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}
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var stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2];
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if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= 2 * originalStateCountTotal) {
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return NaN;
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}
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return this.foundPatternCross(stateCount) ? AlignmentPatternFinder.centerFromEnd(stateCount, i) : NaN;
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};
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/**
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* <p>This is called when a horizontal scan finds a possible alignment pattern. It will
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* cross check with a vertical scan, and if successful, will see if this pattern had been
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* found on a previous horizontal scan. If so, we consider it confirmed and conclude we have
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* found the alignment pattern.</p>
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*
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* @param stateCount reading state module counts from horizontal scan
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* @param i row where alignment pattern may be found
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* @param j end of possible alignment pattern in row
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* @return {@link AlignmentPattern} if we have found the same pattern twice, or null if not
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*/
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AlignmentPatternFinder.prototype.handlePossibleCenter = function (stateCount, i /*int*/, j /*int*/) {
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var e_1, _a;
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var stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2];
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var centerJ = AlignmentPatternFinder.centerFromEnd(stateCount, j);
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var centerI = this.crossCheckVertical(i, /*(int) */ centerJ, 2 * stateCount[1], stateCountTotal);
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if (!isNaN(centerI)) {
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var estimatedModuleSize = (stateCount[0] + stateCount[1] + stateCount[2]) / 3.0;
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try {
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for (var _b = __values(this.possibleCenters), _c = _b.next(); !_c.done; _c = _b.next()) {
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var center = _c.value;
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// Look for about the same center and module size:
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if (center.aboutEquals(estimatedModuleSize, centerI, centerJ)) {
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return center.combineEstimate(centerI, centerJ, estimatedModuleSize);
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}
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}
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}
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catch (e_1_1) { e_1 = { error: e_1_1 }; }
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finally {
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try {
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if (_c && !_c.done && (_a = _b.return)) _a.call(_b);
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}
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finally { if (e_1) throw e_1.error; }
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}
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// Hadn't found this before; save it
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var point = new AlignmentPattern_1.default(centerJ, centerI, estimatedModuleSize);
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this.possibleCenters.push(point);
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if (this.resultPointCallback !== null && this.resultPointCallback !== undefined) {
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this.resultPointCallback.foundPossibleResultPoint(point);
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}
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}
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return null;
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};
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return AlignmentPatternFinder;
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}());
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exports.default = AlignmentPatternFinder;
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