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diff --git a/libraries/zxing/src/com/google/zxing/common/GlobalHistogramBinarizer.java b/libraries/zxing/src/com/google/zxing/common/GlobalHistogramBinarizer.java
deleted file mode 100644
index 4fa2a887b..000000000
--- a/libraries/zxing/src/com/google/zxing/common/GlobalHistogramBinarizer.java
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@@ -1,194 +0,0 @@
-/*
- * Copyright 2009 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.
- */
-
-package com.google.zxing.common;
-
-import com.google.zxing.Binarizer;
-import com.google.zxing.LuminanceSource;
-import com.google.zxing.NotFoundException;
-
-/**
- * This Binarizer implementation uses the old ZXing global histogram approach. It is suitable
- * for low-end mobile devices which don't have enough CPU or memory to use a local thresholding
- * algorithm. However, because it picks a global black point, it cannot handle difficult shadows
- * and gradients.
- *
- * Faster mobile devices and all desktop applications should probably use HybridBinarizer instead.
- *
- * @author dswitkin@google.com (Daniel Switkin)
- * @author Sean Owen
- */
-public class GlobalHistogramBinarizer extends Binarizer {
-
- private static final int LUMINANCE_BITS = 5;
- private static final int LUMINANCE_SHIFT = 8 - LUMINANCE_BITS;
- private static final int LUMINANCE_BUCKETS = 1 << LUMINANCE_BITS;
-
- private byte[] luminances = null;
- private int[] buckets = null;
-
- public GlobalHistogramBinarizer(LuminanceSource source) {
- super(source);
- }
-
- // Applies simple sharpening to the row data to improve performance of the 1D Readers.
- public BitArray getBlackRow(int y, BitArray row) throws NotFoundException {
- LuminanceSource source = getLuminanceSource();
- int width = source.getWidth();
- if (row == null || row.getSize() < width) {
- row = new BitArray(width);
- } else {
- row.clear();
- }
-
- initArrays(width);
- byte[] localLuminances = source.getRow(y, luminances);
- int[] localBuckets = buckets;
- for (int x = 0; x < width; x++) {
- int pixel = localLuminances[x] & 0xff;
- localBuckets[pixel >> LUMINANCE_SHIFT]++;
- }
- int blackPoint = estimateBlackPoint(localBuckets);
-
- int left = localLuminances[0] & 0xff;
- int center = localLuminances[1] & 0xff;
- for (int x = 1; x < width - 1; x++) {
- int right = localLuminances[x + 1] & 0xff;
- // A simple -1 4 -1 box filter with a weight of 2.
- int luminance = ((center << 2) - left - right) >> 1;
- if (luminance < blackPoint) {
- row.set(x);
- }
- left = center;
- center = right;
- }
- return row;
- }
-
- // Does not sharpen the data, as this call is intended to only be used by 2D Readers.
- public BitMatrix getBlackMatrix() throws NotFoundException {
- LuminanceSource source = getLuminanceSource();
- int width = source.getWidth();
- int height = source.getHeight();
- BitMatrix matrix = new BitMatrix(width, height);
-
- // Quickly calculates the histogram by sampling four rows from the image. This proved to be
- // more robust on the blackbox tests than sampling a diagonal as we used to do.
- initArrays(width);
- int[] localBuckets = buckets;
- for (int y = 1; y < 5; y++) {
- int row = height * y / 5;
- byte[] localLuminances = source.getRow(row, luminances);
- int right = (width << 2) / 5;
- for (int x = width / 5; x < right; x++) {
- int pixel = localLuminances[x] & 0xff;
- localBuckets[pixel >> LUMINANCE_SHIFT]++;
- }
- }
- int blackPoint = estimateBlackPoint(localBuckets);
-
- // We delay reading the entire image luminance until the black point estimation succeeds.
- // Although we end up reading four rows twice, it is consistent with our motto of
- // "fail quickly" which is necessary for continuous scanning.
- byte[] localLuminances = source.getMatrix();
- for (int y = 0; y < height; y++) {
- int offset = y * width;
- for (int x = 0; x< width; x++) {
- int pixel = localLuminances[offset + x] & 0xff;
- if (pixel < blackPoint) {
- matrix.set(x, y);
- }
- }
- }
-
- return matrix;
- }
-
- public Binarizer createBinarizer(LuminanceSource source) {
- return new GlobalHistogramBinarizer(source);
- }
-
- private void initArrays(int luminanceSize) {
- if (luminances == null || luminances.length < luminanceSize) {
- luminances = new byte[luminanceSize];
- }
- if (buckets == null) {
- buckets = new int[LUMINANCE_BUCKETS];
- } else {
- for (int x = 0; x < LUMINANCE_BUCKETS; x++) {
- buckets[x] = 0;
- }
- }
- }
-
- private static int estimateBlackPoint(int[] buckets) throws NotFoundException {
- // Find the tallest peak in the histogram.
- int numBuckets = buckets.length;
- int maxBucketCount = 0;
- int firstPeak = 0;
- int firstPeakSize = 0;
- for (int x = 0; x < numBuckets; x++) {
- if (buckets[x] > firstPeakSize) {
- firstPeak = x;
- firstPeakSize = buckets[x];
- }
- if (buckets[x] > maxBucketCount) {
- maxBucketCount = buckets[x];
- }
- }
-
- // Find the second-tallest peak which is somewhat far from the tallest peak.
- int secondPeak = 0;
- int secondPeakScore = 0;
- for (int x = 0; x < numBuckets; x++) {
- int distanceToBiggest = x - firstPeak;
- // Encourage more distant second peaks by multiplying by square of distance.
- int score = buckets[x] * distanceToBiggest * distanceToBiggest;
- if (score > secondPeakScore) {
- secondPeak = x;
- secondPeakScore = score;
- }
- }
-
- // Make sure firstPeak corresponds to the black peak.
- if (firstPeak > secondPeak) {
- int temp = firstPeak;
- firstPeak = secondPeak;
- secondPeak = temp;
- }
-
- // If there is too little contrast in the image to pick a meaningful black point, throw rather
- // than waste time trying to decode the image, and risk false positives.
- if (secondPeak - firstPeak <= numBuckets >> 4) {
- throw NotFoundException.getNotFoundInstance();
- }
-
- // Find a valley between them that is low and closer to the white peak.
- int bestValley = secondPeak - 1;
- int bestValleyScore = -1;
- for (int x = secondPeak - 1; x > firstPeak; x--) {
- int fromFirst = x - firstPeak;
- int score = fromFirst * fromFirst * (secondPeak - x) * (maxBucketCount - buckets[x]);
- if (score > bestValleyScore) {
- bestValley = x;
- bestValleyScore = score;
- }
- }
-
- return bestValley << LUMINANCE_SHIFT;
- }
-
-}