Flips the given bit.
+ * + * @param i row offset + * @param j column offset + */ + public void flip(int i, int j) { + int offset = i + dimension * j; + bits[offset >> 5] ^= 1 << (offset & 0x1F); + } + /** *Sets a square region of the bit matrix to true.
* @@ -108,13 +119,6 @@ public final class BitMatrix { return dimension; } - /** - * @return array of ints holding internal representation of this matrix's bits - */ - public int[] getBits() { - return bits; - } - public String toString() { StringBuffer result = new StringBuffer(dimension * (dimension + 1)); for (int i = 0; i < dimension; i++) { diff --git a/core/src/com/google/zxing/qrcode/decoder/BitMatrixParser.java b/core/src/com/google/zxing/qrcode/decoder/BitMatrixParser.java index 9b8ae482b..59d558f48 100644 --- a/core/src/com/google/zxing/qrcode/decoder/BitMatrixParser.java +++ b/core/src/com/google/zxing/qrcode/decoder/BitMatrixParser.java @@ -161,7 +161,7 @@ final class BitMatrixParser { // some bits from reading as we wind through the bit matrix. DataMask dataMask = DataMask.forReference((int) formatInfo.getDataMask()); int dimension = bitMatrix.getDimension(); - dataMask.unmaskBitMatrix(bitMatrix.getBits(), dimension); + dataMask.unmaskBitMatrix(bitMatrix, dimension); BitMatrix functionPattern = version.buildFunctionPattern(); diff --git a/core/src/com/google/zxing/qrcode/decoder/DataMask.java b/core/src/com/google/zxing/qrcode/decoder/DataMask.java index 6ba1b3547..40d07a52f 100755 --- a/core/src/com/google/zxing/qrcode/decoder/DataMask.java +++ b/core/src/com/google/zxing/qrcode/decoder/DataMask.java @@ -16,6 +16,8 @@ package com.google.zxing.qrcode.decoder; +import com.google.zxing.common.BitMatrix; + /** *Encapsulates data masks for the data bits in a QR code, per ISO 18004:2006 6.8. Implementations * of this class can un-mask a raw BitMatrix. For simplicity, they will unmask the entire BitMatrix, @@ -50,10 +52,20 @@ abstract class DataMask { *
Implementations of this method reverse the data masking process applied to a QR Code and * make its bits ready to read.
* - * @param bits representation of QR Code bits from {@link com.google.zxing.common.BitMatrix#getBits()} + * @param bits representation of QR Code bits * @param dimension dimension of QR Code, represented by bits, being unmasked */ - abstract void unmaskBitMatrix(int[] bits, int dimension); + final void unmaskBitMatrix(BitMatrix bits, int dimension) { + for (int y = 0; y < dimension; y++) { + for (int x = 0; x < dimension; x++) { + if (isMasked(x, y)) { + bits.flip(x, y); + } + } + } + } + + abstract boolean isMasked(int x, int y); /** * @param reference a value between 0 and 7 indicating one of the eight possible @@ -68,166 +80,67 @@ abstract class DataMask { } /** - * 000: mask bits for which (i + j) mod 2 == 0 + * 000: mask bits for which (x + y) mod 2 == 0 */ private static class DataMask000 extends DataMask { - private static final int BITMASK = 0x55555555; // = 010101... - - void unmaskBitMatrix(int[] bits, int dimension) { - // This one's easy. Because the dimension of BitMatrix is always odd, - // we can merely flip every other bit - int max = bits.length; - for (int i = 0; i < max; i++) { - bits[i] ^= BITMASK; - } + boolean isMasked(int x, int y) { + return ((x + y) & 0x01) == 0; } } /** - * 001: mask bits for which i mod 2 == 0 + * 001: mask bits for which x mod 2 == 0 */ private static class DataMask001 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - for (int i = 0; i < dimension; i++) { - if ((i & 0x01) == 0) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + return (x & 0x01) == 0; } } /** - * 010: mask bits for which j mod 3 == 0 + * 010: mask bits for which y mod 3 == 0 */ private static class DataMask010 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - boolean columnMasked = j % 3 == 0; - for (int i = 0; i < dimension; i++) { - if (columnMasked) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + return y % 3 == 0; } } /** - * 011: mask bits for which (i + j) mod 3 == 0 + * 011: mask bits for which (x + y) mod 3 == 0 */ private static class DataMask011 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - for (int i = 0; i < dimension; i++) { - if ((i + j) % 3 == 0) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + return (x + y) % 3 == 0; } } /** - * 100: mask bits for which (i/2 + j/3) mod 2 == 0 + * 100: mask bits for which (x/2 + y/3) mod 2 == 0 */ private static class DataMask100 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - int jComponentParity = (j / 3) & 0x01; - for (int i = 0; i < dimension; i++) { - if (((i >> 1) & 0x01) == jComponentParity) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + return (((x >>> 1) + (y/3)) & 0x01) == 0; } } /** - * 101: mask bits for which ij mod 2 + ij mod 3 == 0 + * 101: mask bits for which xy mod 2 + xy mod 3 == 0 */ private static class DataMask101 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - for (int i = 0; i < dimension; i++) { - int product = i * j; - if (((product & 0x01) == 0) && product % 3 == 0) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + int temp = x * y; + return (temp & 0x01) + (temp % 3) == 0; } } /** - * 110: mask bits for which (ij mod 2 + ij mod 3) mod 2 == 0 + * 110: mask bits for which (xy mod 2 + xy mod 3) mod 2 == 0 */ private static class DataMask110 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - for (int i = 0; i < dimension; i++) { - int product = i * j; - if ((((product & 0x01) + product % 3) & 0x01) == 0) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + int temp = x * y; + return (((temp & 0x01) + (temp % 3)) & 0x01) == 0; } } @@ -235,23 +148,8 @@ abstract class DataMask { * 111: mask bits for which ((i+j)mod 2 + ij mod 3) mod 2 == 0 */ private static class DataMask111 extends DataMask { - void unmaskBitMatrix(int[] bits, int dimension) { - int bitMask = 0; - int count = 0; - int offset = 0; - for (int j = 0; j < dimension; j++) { - for (int i = 0; i < dimension; i++) { - if (((((i + j) & 0x01) + (i * j) % 3) & 0x01) == 0) { - bitMask |= 1 << count; - } - if (++count == 32) { - bits[offset++] ^= bitMask; - count = 0; - bitMask = 0; - } - } - } - bits[offset] ^= bitMask; + boolean isMasked(int x, int y) { + return ((((x + y) & 0x01) + ((x * y) % 3)) & 0x01) == 0; } } } diff --git a/core/test/src/com/google/zxing/common/BitMatrixTestCase.java b/core/test/src/com/google/zxing/common/BitMatrixTestCase.java index 1bb83519c..48ef90c79 100644 --- a/core/test/src/com/google/zxing/common/BitMatrixTestCase.java +++ b/core/test/src/com/google/zxing/common/BitMatrixTestCase.java @@ -50,13 +50,4 @@ public final class BitMatrixTestCase extends TestCase { } } - public void testGetBits() { - BitMatrix matrix = new BitMatrix(6); - matrix.set(0, 0); - matrix.set(5, 5); - int[] bits = matrix.getBits(); - assertEquals(1, bits[0]); - assertEquals(8, bits[1]); - } - } \ No newline at end of file diff --git a/core/test/src/com/google/zxing/qrcode/decoder/DataMaskTestCase.java b/core/test/src/com/google/zxing/qrcode/decoder/DataMaskTestCase.java index 41a8ddaf0..1f15ce69a 100644 --- a/core/test/src/com/google/zxing/qrcode/decoder/DataMaskTestCase.java +++ b/core/test/src/com/google/zxing/qrcode/decoder/DataMaskTestCase.java @@ -99,7 +99,7 @@ public final class DataMaskTestCase extends TestCase { private void testMask(DataMask mask, int dimension, MaskCondition condition) { BitMatrix bits = new BitMatrix(dimension); - mask.unmaskBitMatrix(bits.getBits(), dimension); + mask.unmaskBitMatrix(bits, dimension); for (int i = 0; i < dimension; i++) { for (int j = 0; j < dimension; j++) { assertEquals(