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partial port of finder pattern finder
This commit is contained in:
Henry Schimke
709
src/qrcode/detector/finder_pattern_finder.rs
Executable file
709
src/qrcode/detector/finder_pattern_finder.rs
Executable file
@@ -0,0 +1,709 @@
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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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use crate::{common::BitMatrix, RXingResultPointCallback, DecodingHintDictionary};
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use super::{FinderPattern, FinderPatternInfo};
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/**
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* <p>This class attempts to find finder patterns in a QR Code. Finder patterns are the square
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* markers at three corners of a QR 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.
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*
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* @author Sean Owen
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*/
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pub struct FinderPatternFinder {
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image:BitMatrix,
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possibleCenters:Vec<FinderPattern>,
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hasSkipped:bool,
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crossCheckStateCount:Vec<u32>,
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resultPointCallback:Option<RXingResultPointCallback>,
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}
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impl FinderPatternFinder{
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const CENTER_QUORUM :u32= 2;
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// private static final EstimatedModuleComparator moduleComparator = new EstimatedModuleComparator();
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const MIN_SKIP :u32 = 3; // 1 pixel/module times 3 modules/center
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const MAX_MODULES:u32 = 97; // support up to version 20 for mobile clients
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/**
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* <p>Creates a finder that will search the image for three finder patterns.</p>
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*
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* @param image image to search
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*/
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pub fn new( image:BitMatrix) -> Self{
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Self::with_callback(image, None)
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}
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pub fn with_callback( image:BitMatrix, resultPointCallback:Option<RXingResultPointCallback>) -> Self{
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Self {
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image,
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possibleCenters: Vec::new(),
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hasSkipped: false,
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crossCheckStateCount: [0u32;5],
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resultPointCallback,
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}
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}
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pub fn getImage(&self) -> &BitMatrix{
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&self.image
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}
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pub fn getPossibleCenters(&self) -> &Vec<FinderPattern>{
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&self.possibleCenters
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}
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pub fn find(&self, hints:&DecodingHintDictionary) -> Result<FinderPatternInfo,Exceptions> {
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boolean tryHarder = hints != null && hints.containsKey(DecodeHintType.TRY_HARDER);
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int maxI = image.getHeight();
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int maxJ = image.getWidth();
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// We are looking for black/white/black/white/black modules in
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// 1:1:3:1:1 ratio; this tracks the number of such modules seen so far
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// Let's assume that the maximum version QR Code we support takes up 1/4 the height of the
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// image, and then account for the center being 3 modules in size. This gives the smallest
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// number of pixels the center could be, so skip this often. When trying harder, look for all
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// QR versions regardless of how dense they are.
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int iSkip = (3 * maxI) / (4 * MAX_MODULES);
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if (iSkip < MIN_SKIP || tryHarder) {
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iSkip = MIN_SKIP;
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}
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boolean done = false;
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int[] stateCount = new int[5];
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for (int i = iSkip - 1; i < maxI && !done; i += iSkip) {
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// Get a row of black/white values
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doClearCounts(stateCount);
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int currentState = 0;
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for (int j = 0; j < maxJ; j++) {
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if (image.get(j, i)) {
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// Black pixel
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if ((currentState & 1) == 1) { // Counting white pixels
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currentState++;
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}
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stateCount[currentState]++;
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} else { // White pixel
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if ((currentState & 1) == 0) { // Counting black pixels
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if (currentState == 4) { // A winner?
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if (foundPatternCross(stateCount)) { // Yes
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boolean confirmed = handlePossibleCenter(stateCount, i, j);
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if (confirmed) {
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// Start examining every other line. Checking each line turned out to be too
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// expensive and didn't improve performance.
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iSkip = 2;
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if (hasSkipped) {
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done = haveMultiplyConfirmedCenters();
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} else {
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int rowSkip = findRowSkip();
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if (rowSkip > stateCount[2]) {
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// Skip rows between row of lower confirmed center
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// and top of presumed third confirmed center
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// but back up a bit to get a full chance of detecting
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// it, entire width of center of finder pattern
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// Skip by rowSkip, but back off by stateCount[2] (size of last center
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// of pattern we saw) to be conservative, and also back off by iSkip which
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// is about to be re-added
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i += rowSkip - stateCount[2] - iSkip;
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j = maxJ - 1;
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}
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}
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} else {
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doShiftCounts2(stateCount);
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currentState = 3;
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continue;
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}
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// Clear state to start looking again
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currentState = 0;
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doClearCounts(stateCount);
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} else { // No, shift counts back by two
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doShiftCounts2(stateCount);
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currentState = 3;
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}
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} else {
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stateCount[++currentState]++;
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}
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} else { // Counting white pixels
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stateCount[currentState]++;
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}
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}
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}
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if (foundPatternCross(stateCount)) {
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boolean confirmed = handlePossibleCenter(stateCount, i, maxJ);
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if (confirmed) {
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iSkip = stateCount[0];
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if (hasSkipped) {
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// Found a third one
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done = haveMultiplyConfirmedCenters();
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}
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}
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}
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}
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FinderPattern[] patternInfo = selectBestPatterns();
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RXingResultPoint.orderBestPatterns(patternInfo);
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return new FinderPatternInfo(patternInfo);
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}
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/**
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* Given a count of black/white/black/white/black pixels just seen and an end position,
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* figures the location of the center of this run.
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*/
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fn centerFromEnd(stateCount:&[u32], end:u32) -> f32 {
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return (end - stateCount[4] - stateCount[3]) - stateCount[2] / 2.0f;
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}
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/**
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* @param stateCount count of black/white/black/white/black pixels just read
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* @return true iff the proportions of the counts is close enough to the 1/1/3/1/1 ratios
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* used by finder patterns to be considered a match
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*/
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pub fn foundPatternCross( stateCount:&[u32]) -> bool{
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int totalModuleSize = 0;
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for (int i = 0; i < 5; i++) {
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int count = stateCount[i];
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if (count == 0) {
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return false;
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}
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totalModuleSize += count;
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}
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if (totalModuleSize < 7) {
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return false;
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}
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float moduleSize = totalModuleSize / 7.0f;
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float maxVariance = moduleSize / 2.0f;
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// Allow less than 50% variance from 1-1-3-1-1 proportions
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return
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Math.abs(moduleSize - stateCount[0]) < maxVariance &&
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Math.abs(moduleSize - stateCount[1]) < maxVariance &&
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Math.abs(3.0f * moduleSize - stateCount[2]) < 3 * maxVariance &&
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Math.abs(moduleSize - stateCount[3]) < maxVariance &&
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Math.abs(moduleSize - stateCount[4]) < maxVariance;
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}
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/**
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* @param stateCount count of black/white/black/white/black pixels just read
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* @return true iff the proportions of the counts is close enough to the 1/1/3/1/1 ratios
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* used by finder patterns to be considered a match
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*/
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pub fn foundPatternDiagonal( stateCount: &[u32]) -> bool{
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int totalModuleSize = 0;
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for (int i = 0; i < 5; i++) {
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int count = stateCount[i];
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if (count == 0) {
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return false;
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}
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totalModuleSize += count;
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}
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if (totalModuleSize < 7) {
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return false;
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}
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float moduleSize = totalModuleSize / 7.0f;
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float maxVariance = moduleSize / 1.333f;
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// Allow less than 75% variance from 1-1-3-1-1 proportions
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return
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Math.abs(moduleSize - stateCount[0]) < maxVariance &&
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Math.abs(moduleSize - stateCount[1]) < maxVariance &&
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Math.abs(3.0f * moduleSize - stateCount[2]) < 3 * maxVariance &&
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Math.abs(moduleSize - stateCount[3]) < maxVariance &&
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Math.abs(moduleSize - stateCount[4]) < maxVariance;
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}
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fn getCrossCheckStateCount(&self) -> &[u32] {
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doClearCounts(crossCheckStateCount);
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return crossCheckStateCount;
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}
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#[deprecated]
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pub fn clearCounts(&self, counts:&[u32]) {
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doClearCounts(counts);
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}
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#[deprecated]
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pub fn shiftCounts2(&self, stateCount:&[u32]) {
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doShiftCounts2(stateCount);
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}
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pub fn doClearCounts(icounts:&[u32]) {
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Arrays.fill(counts, 0);
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}
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pub fn doShiftCounts2( stateCount:&[u32]) {
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stateCount[0] = stateCount[2];
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stateCount[1] = stateCount[3];
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stateCount[2] = stateCount[4];
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stateCount[3] = 1;
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stateCount[4] = 0;
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}
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/**
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* After a vertical and horizontal scan finds a potential finder pattern, this method
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* "cross-cross-cross-checks" by scanning down diagonally through the center of the possible
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* finder pattern to see if the same proportion is detected.
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*
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* @param centerI row where a finder pattern was detected
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* @param centerJ center of the section that appears to cross a finder pattern
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* @return true if proportions are withing expected limits
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*/
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fn crossCheckDiagonal(&self, centerI:u32, centerJ:u32) -> bool{
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int[] stateCount = getCrossCheckStateCount();
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// Start counting up, left from center finding black center mass
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int i = 0;
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while (centerI >= i && centerJ >= i && image.get(centerJ - i, centerI - i)) {
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stateCount[2]++;
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i++;
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}
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if (stateCount[2] == 0) {
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return false;
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}
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// Continue up, left finding white space
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while (centerI >= i && centerJ >= i && !image.get(centerJ - i, centerI - i)) {
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stateCount[1]++;
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i++;
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}
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if (stateCount[1] == 0) {
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return false;
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}
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// Continue up, left finding black border
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while (centerI >= i && centerJ >= i && image.get(centerJ - i, centerI - i)) {
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stateCount[0]++;
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i++;
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}
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if (stateCount[0] == 0) {
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return false;
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}
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int maxI = image.getHeight();
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int maxJ = image.getWidth();
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// Now also count down, right from center
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i = 1;
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while (centerI + i < maxI && centerJ + i < maxJ && image.get(centerJ + i, centerI + i)) {
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stateCount[2]++;
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i++;
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}
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while (centerI + i < maxI && centerJ + i < maxJ && !image.get(centerJ + i, centerI + i)) {
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stateCount[3]++;
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i++;
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}
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if (stateCount[3] == 0) {
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return false;
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}
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while (centerI + i < maxI && centerJ + i < maxJ && image.get(centerJ + i, centerI + i)) {
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stateCount[4]++;
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i++;
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}
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if (stateCount[4] == 0) {
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return false;
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}
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return foundPatternDiagonal(stateCount);
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}
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/**
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* <p>After a horizontal scan finds a potential finder pattern, this method
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* "cross-checks" by scanning down vertically through the center of the possible
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* finder pattern to see if the same proportion is detected.</p>
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*
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* @param startI row where a finder pattern was detected
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* @param centerJ center of the section that appears to cross a finder 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 finder pattern, or {@link Float#NaN} if not found
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*/
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fn crossCheckVertical( &self, startI:u32, centerJ:u32, maxCount:u32,
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originalStateCountTotal:u32) -> f32{
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BitMatrix image = this.image;
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int maxI = image.getHeight();
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int[] stateCount = getCrossCheckStateCount();
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// Start counting up from center
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int i = startI;
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while (i >= 0 && image.get(centerJ, i)) {
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stateCount[2]++;
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i--;
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}
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if (i < 0) {
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return Float.NaN;
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}
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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 Float.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 Float.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)) {
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stateCount[2]++;
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i++;
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}
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if (i == maxI) {
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return Float.NaN;
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}
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while (i < maxI && !image.get(centerJ, i) && stateCount[3] < maxCount) {
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stateCount[3]++;
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i++;
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}
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if (i == maxI || stateCount[3] >= maxCount) {
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return Float.NaN;
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}
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while (i < maxI && image.get(centerJ, i) && stateCount[4] < maxCount) {
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stateCount[4]++;
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i++;
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}
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if (stateCount[4] >= maxCount) {
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return Float.NaN;
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}
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// If we found a finder-pattern-like section, but its size is more than 40% different than
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// the original, assume it's a false positive
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int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2] + stateCount[3] +
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stateCount[4];
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if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= 2 * originalStateCountTotal) {
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return Float.NaN;
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}
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return foundPatternCross(stateCount) ? centerFromEnd(stateCount, i) : Float.NaN;
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}
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/**
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* <p>Like {@link #crossCheckVertical(int, int, int, int)}, and in fact is basically identical,
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* except it reads horizontally instead of vertically. This is used to cross-cross
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* check a vertical cross check and locate the real center of the alignment pattern.</p>
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*/
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fn crossCheckHorizontal(&self, startJ:u32, centerI:u32, maxCount:u32,
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originalStateCountTotal:u32) -> f32{
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BitMatrix image = this.image;
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||||
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int maxJ = image.getWidth();
|
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int[] stateCount = getCrossCheckStateCount();
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int j = startJ;
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while (j >= 0 && image.get(j, centerI)) {
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stateCount[2]++;
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j--;
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}
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if (j < 0) {
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return Float.NaN;
|
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}
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while (j >= 0 && !image.get(j, centerI) && stateCount[1] <= maxCount) {
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stateCount[1]++;
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j--;
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}
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if (j < 0 || stateCount[1] > maxCount) {
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return Float.NaN;
|
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}
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while (j >= 0 && image.get(j, centerI) && stateCount[0] <= maxCount) {
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stateCount[0]++;
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j--;
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}
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if (stateCount[0] > maxCount) {
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return Float.NaN;
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}
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||||
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j = startJ + 1;
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||||
while (j < maxJ && image.get(j, centerI)) {
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stateCount[2]++;
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||||
j++;
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||||
}
|
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if (j == maxJ) {
|
||||
return Float.NaN;
|
||||
}
|
||||
while (j < maxJ && !image.get(j, centerI) && stateCount[3] < maxCount) {
|
||||
stateCount[3]++;
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||||
j++;
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||||
}
|
||||
if (j == maxJ || stateCount[3] >= maxCount) {
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||||
return Float.NaN;
|
||||
}
|
||||
while (j < maxJ && image.get(j, centerI) && stateCount[4] < maxCount) {
|
||||
stateCount[4]++;
|
||||
j++;
|
||||
}
|
||||
if (stateCount[4] >= maxCount) {
|
||||
return Float.NaN;
|
||||
}
|
||||
|
||||
// If we found a finder-pattern-like section, but its size is significantly different than
|
||||
// the original, assume it's a false positive
|
||||
int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2] + stateCount[3] +
|
||||
stateCount[4];
|
||||
if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= originalStateCountTotal) {
|
||||
return Float.NaN;
|
||||
}
|
||||
|
||||
return foundPatternCross(stateCount) ? centerFromEnd(stateCount, j) : Float.NaN;
|
||||
}
|
||||
|
||||
/**
|
||||
* @param stateCount reading state module counts from horizontal scan
|
||||
* @param i row where finder pattern may be found
|
||||
* @param j end of possible finder pattern in row
|
||||
* @param pureBarcode ignored
|
||||
* @return true if a finder pattern candidate was found this time
|
||||
* @deprecated only exists for backwards compatibility
|
||||
* @see #handlePossibleCenter(int[], int, int)
|
||||
*/
|
||||
#[deprecated]
|
||||
pub fn handlePossibleCenter(&self, stateCount:&[u32], i:u32, j:u32, pureBarcode:bool) -> bool{
|
||||
return handlePossibleCenter(stateCount, i, j);
|
||||
}
|
||||
|
||||
/**
|
||||
* <p>This is called when a horizontal scan finds a possible alignment pattern. It will
|
||||
* cross check with a vertical scan, and if successful, will, ah, cross-cross-check
|
||||
* with another horizontal scan. This is needed primarily to locate the real horizontal
|
||||
* center of the pattern in cases of extreme skew.
|
||||
* And then we cross-cross-cross check with another diagonal scan.</p>
|
||||
*
|
||||
* <p>If that succeeds the finder pattern location is added to a list that tracks
|
||||
* the number of times each location has been nearly-matched as a finder pattern.
|
||||
* Each additional find is more evidence that the location is in fact a finder
|
||||
* pattern center
|
||||
*
|
||||
* @param stateCount reading state module counts from horizontal scan
|
||||
* @param i row where finder pattern may be found
|
||||
* @param j end of possible finder pattern in row
|
||||
* @return true if a finder pattern candidate was found this time
|
||||
*/
|
||||
pub fn handlePossibleCenter(&self, stateCount:&[u32], i:u32, j:u32) -> bool{
|
||||
int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2] + stateCount[3] +
|
||||
stateCount[4];
|
||||
float centerJ = centerFromEnd(stateCount, j);
|
||||
float centerI = crossCheckVertical(i, (int) centerJ, stateCount[2], stateCountTotal);
|
||||
if (!Float.isNaN(centerI)) {
|
||||
// Re-cross check
|
||||
centerJ = crossCheckHorizontal((int) centerJ, (int) centerI, stateCount[2], stateCountTotal);
|
||||
if (!Float.isNaN(centerJ) && crossCheckDiagonal((int) centerI, (int) centerJ)) {
|
||||
float estimatedModuleSize = stateCountTotal / 7.0f;
|
||||
boolean found = false;
|
||||
for (int index = 0; index < possibleCenters.size(); index++) {
|
||||
FinderPattern center = possibleCenters.get(index);
|
||||
// Look for about the same center and module size:
|
||||
if (center.aboutEquals(estimatedModuleSize, centerI, centerJ)) {
|
||||
possibleCenters.set(index, center.combineEstimate(centerI, centerJ, estimatedModuleSize));
|
||||
found = true;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (!found) {
|
||||
FinderPattern point = new FinderPattern(centerJ, centerI, estimatedModuleSize);
|
||||
possibleCenters.add(point);
|
||||
if (resultPointCallback != null) {
|
||||
resultPointCallback.foundPossibleRXingResultPoint(point);
|
||||
}
|
||||
}
|
||||
return true;
|
||||
}
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return number of rows we could safely skip during scanning, based on the first
|
||||
* two finder patterns that have been located. In some cases their position will
|
||||
* allow us to infer that the third pattern must lie below a certain point farther
|
||||
* down in the image.
|
||||
*/
|
||||
fn findRowSkip(&self) -> u32{
|
||||
int max = possibleCenters.size();
|
||||
if (max <= 1) {
|
||||
return 0;
|
||||
}
|
||||
RXingResultPoint firstConfirmedCenter = null;
|
||||
for (FinderPattern center : possibleCenters) {
|
||||
if (center.getCount() >= CENTER_QUORUM) {
|
||||
if (firstConfirmedCenter == null) {
|
||||
firstConfirmedCenter = center;
|
||||
} else {
|
||||
// We have two confirmed centers
|
||||
// How far down can we skip before resuming looking for the next
|
||||
// pattern? In the worst case, only the difference between the
|
||||
// difference in the x / y coordinates of the two centers.
|
||||
// This is the case where you find top left last.
|
||||
hasSkipped = true;
|
||||
return (int) (Math.abs(firstConfirmedCenter.getX() - center.getX()) -
|
||||
Math.abs(firstConfirmedCenter.getY() - center.getY())) / 2;
|
||||
}
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return true iff we have found at least 3 finder patterns that have been detected
|
||||
* at least {@link #CENTER_QUORUM} times each, and, the estimated module size of the
|
||||
* candidates is "pretty similar"
|
||||
*/
|
||||
fn haveMultiplyConfirmedCenters(&self) -> bool {
|
||||
int confirmedCount = 0;
|
||||
float totalModuleSize = 0.0f;
|
||||
int max = possibleCenters.size();
|
||||
for (FinderPattern pattern : possibleCenters) {
|
||||
if (pattern.getCount() >= CENTER_QUORUM) {
|
||||
confirmedCount++;
|
||||
totalModuleSize += pattern.getEstimatedModuleSize();
|
||||
}
|
||||
}
|
||||
if (confirmedCount < 3) {
|
||||
return false;
|
||||
}
|
||||
// OK, we have at least 3 confirmed centers, but, it's possible that one is a "false positive"
|
||||
// and that we need to keep looking. We detect this by asking if the estimated module sizes
|
||||
// vary too much. We arbitrarily say that when the total deviation from average exceeds
|
||||
// 5% of the total module size estimates, it's too much.
|
||||
float average = totalModuleSize / max;
|
||||
float totalDeviation = 0.0f;
|
||||
for (FinderPattern pattern : possibleCenters) {
|
||||
totalDeviation += Math.abs(pattern.getEstimatedModuleSize() - average);
|
||||
}
|
||||
return totalDeviation <= 0.05f * totalModuleSize;
|
||||
}
|
||||
|
||||
/**
|
||||
* Get square of distance between a and b.
|
||||
*/
|
||||
fn squaredDistance( a:&FinderPattern, b:&FinderPattern) -> f64{
|
||||
double x = a.getX() - b.getX();
|
||||
double y = a.getY() - b.getY();
|
||||
return x * x + y * y;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return the 3 best {@link FinderPattern}s from our list of candidates. The "best" are
|
||||
* those have similar module size and form a shape closer to a isosceles right triangle.
|
||||
* @throws NotFoundException if 3 such finder patterns do not exist
|
||||
*/
|
||||
fn selectBestPatterns(&self) -> Result<Vec<FinderPattern>,Exceptions> {
|
||||
|
||||
int startSize = possibleCenters.size();
|
||||
if (startSize < 3) {
|
||||
// Couldn't find enough finder patterns
|
||||
throw NotFoundException.getNotFoundInstance();
|
||||
}
|
||||
|
||||
possibleCenters.sort(moduleComparator);
|
||||
|
||||
double distortion = Double.MAX_VALUE;
|
||||
FinderPattern[] bestPatterns = new FinderPattern[3];
|
||||
|
||||
for (int i = 0; i < possibleCenters.size() - 2; i++) {
|
||||
FinderPattern fpi = possibleCenters.get(i);
|
||||
float minModuleSize = fpi.getEstimatedModuleSize();
|
||||
|
||||
for (int j = i + 1; j < possibleCenters.size() - 1; j++) {
|
||||
FinderPattern fpj = possibleCenters.get(j);
|
||||
double squares0 = squaredDistance(fpi, fpj);
|
||||
|
||||
for (int k = j + 1; k < possibleCenters.size(); k++) {
|
||||
FinderPattern fpk = possibleCenters.get(k);
|
||||
float maxModuleSize = fpk.getEstimatedModuleSize();
|
||||
if (maxModuleSize > minModuleSize * 1.4f) {
|
||||
// module size is not similar
|
||||
continue;
|
||||
}
|
||||
|
||||
double a = squares0;
|
||||
double b = squaredDistance(fpj, fpk);
|
||||
double c = squaredDistance(fpi, fpk);
|
||||
|
||||
// sorts ascending - inlined
|
||||
if (a < b) {
|
||||
if (b > c) {
|
||||
if (a < c) {
|
||||
double temp = b;
|
||||
b = c;
|
||||
c = temp;
|
||||
} else {
|
||||
double temp = a;
|
||||
a = c;
|
||||
c = b;
|
||||
b = temp;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
if (b < c) {
|
||||
if (a < c) {
|
||||
double temp = a;
|
||||
a = b;
|
||||
b = temp;
|
||||
} else {
|
||||
double temp = a;
|
||||
a = b;
|
||||
b = c;
|
||||
c = temp;
|
||||
}
|
||||
} else {
|
||||
double temp = a;
|
||||
a = c;
|
||||
c = temp;
|
||||
}
|
||||
}
|
||||
|
||||
// a^2 + b^2 = c^2 (Pythagorean theorem), and a = b (isosceles triangle).
|
||||
// Since any right triangle satisfies the formula c^2 - b^2 - a^2 = 0,
|
||||
// we need to check both two equal sides separately.
|
||||
// The value of |c^2 - 2 * b^2| + |c^2 - 2 * a^2| increases as dissimilarity
|
||||
// from isosceles right triangle.
|
||||
double d = Math.abs(c - 2 * b) + Math.abs(c - 2 * a);
|
||||
if (d < distortion) {
|
||||
distortion = d;
|
||||
bestPatterns[0] = fpi;
|
||||
bestPatterns[1] = fpj;
|
||||
bestPatterns[2] = fpk;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (distortion == Double.MAX_VALUE) {
|
||||
throw NotFoundException.getNotFoundInstance();
|
||||
}
|
||||
|
||||
return bestPatterns;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
// /**
|
||||
// * <p>Orders by {@link FinderPattern#getEstimatedModuleSize()}</p>
|
||||
// */
|
||||
// private static final class EstimatedModuleComparator implements Comparator<FinderPattern>, Serializable {
|
||||
// @Override
|
||||
// public int compare(FinderPattern center1, FinderPattern center2) {
|
||||
// return Float.compare(center1.getEstimatedModuleSize(), center2.getEstimatedModuleSize());
|
||||
// }
|
||||
// }
|
||||
Reference in New Issue
Block a user