This commit is contained in:
Henry Schimke
2022-08-20 17:21:14 -05:00
parent d56e0a2674
commit f53b5ecc2a
15 changed files with 1551 additions and 1617 deletions

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/*
* Copyright 2007 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;
/**
* Thrown when a barcode was successfully detected and decoded, but
* was not returned because its checksum feature failed.
*
* @author Sean Owen
*/
public final class ChecksumException extends ReaderException {
private static final ChecksumException INSTANCE = new ChecksumException();
static {
INSTANCE.setStackTrace(NO_TRACE); // since it's meaningless
}
private ChecksumException() {
// do nothing
}
private ChecksumException(Throwable cause) {
super(cause);
}
public static ChecksumException getChecksumInstance() {
return isStackTrace ? new ChecksumException() : INSTANCE;
}
public static ChecksumException getChecksumInstance(Throwable cause) {
return isStackTrace ? new ChecksumException(cause) : INSTANCE;
}
}

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/*
* Copyright 2007 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;
/**
* Thrown when a barcode was successfully detected, but some aspect of
* the content did not conform to the barcode's format rules. This could have
* been due to a mis-detection.
*
* @author Sean Owen
*/
public final class FormatException extends ReaderException {
private static final FormatException INSTANCE = new FormatException();
static {
INSTANCE.setStackTrace(NO_TRACE); // since it's meaningless
}
private FormatException() {
}
private FormatException(Throwable cause) {
super(cause);
}
public static FormatException getFormatInstance() {
return isStackTrace ? new FormatException() : INSTANCE;
}
public static FormatException getFormatInstance(Throwable cause) {
return isStackTrace ? new FormatException(cause) : INSTANCE;
}
}

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/*
* Copyright 2007 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;
/**
* Thrown when a barcode was not found in the image. It might have been
* partially detected but could not be confirmed.
*
* @author Sean Owen
*/
public final class NotFoundException extends ReaderException {
private static final NotFoundException INSTANCE = new NotFoundException();
static {
INSTANCE.setStackTrace(NO_TRACE); // since it's meaningless
}
private NotFoundException() {
// do nothing
}
public static NotFoundException getNotFoundInstance() {
return isStackTrace ? new NotFoundException() : INSTANCE;
}
}

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/*
* Copyright 2007 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;
/**
* The general exception class throw when something goes wrong during decoding of a barcode.
* This includes, but is not limited to, failing checksums / error correction algorithms, being
* unable to locate finder timing patterns, and so on.
*
* @author Sean Owen
*/
public abstract class ReaderException extends Exception {
// disable stack traces when not running inside test units
protected static boolean isStackTrace =
System.getProperty("surefire.test.class.path") != null;
protected static final StackTraceElement[] NO_TRACE = new StackTraceElement[0];
ReaderException() {
// do nothing
}
ReaderException(Throwable cause) {
super(cause);
}
// Prevent stack traces from being taken
@Override
public final synchronized Throwable fillInStackTrace() {
return null;
}
/**
* For testing only. Controls whether library exception classes include stack traces or not.
* Defaults to false, unless running in the project's unit testing harness.
*
* @param enabled if true, enables stack traces in library exception classes
* @since 3.5.0
*/
public static void setStackTrace(boolean enabled) {
isStackTrace = enabled;
}
}

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/*
* Copyright 2008 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;
/**
* A base class which covers the range of exceptions which may occur when encoding a barcode using
* the Writer framework.
*
* @author dswitkin@google.com (Daniel Switkin)
*/
public final class WriterException extends Exception {
public WriterException() {
}
public WriterException(String message) {
super(message);
}
public WriterException(Throwable cause) {
super(cause);
}
}

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/*
* 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.detector;
use crate::common::BitMatrix;
use crate::{NotFoundException, RXingResultPoint};
/**
* <p>A somewhat generic detector that looks for a barcode-like rectangular region within an image.
* It looks within a mostly white region of an image for a region of black and white, but mostly
* black. It returns the four corners of the region, as best it can determine.</p>
*
* @author Sean Owen
* @deprecated without replacement since 3.3.0
*/
const MAX_MODULES : i32 = 32;
#[deprecated]
pub struct MonochromeRectangleDetector {
image: BitMatrix,
}
impl MonochromeRectangleDetector {
pub fn new(image: &BitMatrix) -> Self {
Self {
image: image,
}
}
/**
* <p>Detects a rectangular region of black and white -- mostly black -- with a region of mostly
* white, in an image.</p>
*
* @return {@link RXingResultPoint}[] describing the corners of the rectangular region. The first and
* last points are opposed on the diagonal, as are the second and third. The first point will be
* the topmost point and the last, the bottommost. The second point will be leftmost and the
* third, the rightmost
* @throws NotFoundException if no Data Matrix Code can be found
*/
pub fn detect(&self) -> Result<Vec<RXingResultPoint>, NotFoundException> {
let height = self.image.getHeight();
let width = self.image.getWidth();
let halfHeight = height / 2;
let halfWidth = width / 2;
let deltaY = 1.max( height / (MAX_MODULES * 8));
let deltaX = 1.max( width / (MAX_MODULES * 8));
let top = 0;
let bottom = height;
let left = 0;
let right = width;
let pointA = self.findCornerFromCenter(
halfWidth,
0,
left,
right,
halfHeight,
-deltaY,
top,
bottom,
halfWidth / 2,
)?;
top = pointA.getY() - 1;
let pointB = self.findCornerFromCenter(
halfWidth,
-deltaX,
left,
right,
halfHeight,
0,
top,
bottom,
halfHeight / 2,
)?;
left = pointB.getX() - 1;
let pointC = self.findCornerFromCenter(
halfWidth,
deltaX,
left,
right,
halfHeight,
0,
top,
bottom,
halfHeight / 2,
)?;
right = pointC.getX() + 1;
let pointD = self.findCornerFromCenter(
halfWidth,
0,
left,
right,
halfHeight,
deltaY,
top,
bottom,
halfWidth / 2,
)?;
bottom = pointD.getY() + 1;
// Go try to find point A again with better information -- might have been off at first.
pointA = self.findCornerFromCenter(
halfWidth,
0,
left,
right,
halfHeight,
-deltaY,
top,
bottom,
halfWidth / 4,
)?;
return vec!([pointA, pointB, pointC, pointD]);
}
/**
* Attempts to locate a corner of the barcode by scanning up, down, left or right from a center
* point which should be within the barcode.
*
* @param centerX center's x component (horizontal)
* @param deltaX same as deltaY but change in x per step instead
* @param left minimum value of x
* @param right maximum value of x
* @param centerY center's y component (vertical)
* @param deltaY change in y per step. If scanning up this is negative; down, positive;
* left or right, 0
* @param top minimum value of y to search through (meaningless when di == 0)
* @param bottom maximum value of y
* @param maxWhiteRun maximum run of white pixels that can still be considered to be within
* the barcode
* @return a {@link RXingResultPoint} encapsulating the corner that was found
* @throws NotFoundException if such a point cannot be found
*/
fn findCornerFromCenter(
&self,
centerX: i32,
deltaX: i32,
left: i32,
right: i32,
centerY: i32,
deltaY: i32,
top: i32,
bottom: i32,
maxWhiteRun: i32,
) -> Result<RXingResultPoint, NotFoundException> {
let lastRange : Option<Vec<i32>> = None;
let y: i32 = centerY;
let x: i32 = centerX;
while (y < bottom && y >= top && x < right && x >= left) {
let range: Option<Vec<i32>>;
if (deltaX == 0) {
// horizontal slices, up and down
range = self.blackWhiteRange(y, maxWhiteRun, left, right, true);
} else {
// vertical slices, left and right
range = self.blackWhiteRange(x, maxWhiteRun, top, bottom, false);
}
if (range .is_none()) {
if (lastRange .is_none()) {
return Err(NotFoundException.getNotFoundInstance());
}
// lastRange was found
if (deltaX == 0) {
let lastY = y - deltaY;
if (lastRange[0] < centerX) {
if (lastRange[1] > centerX) {
// straddle, choose one or the other based on direction
return RXingResultPoint::new(
lastRange[if deltaY > 0 { 0 } else { 1 }],
lastY,
);
}
return RXingResultPoint::new(lastRange[0], lastY);
} else {
return RXingResultPoint::new(lastRange[1], lastY);
}
} else {
let lastX = x - deltaX;
if (lastRange[0] < centerY) {
if (lastRange[1] > centerY) {
return RXingResultPoint::new(
lastX,
lastRange[if deltaX < 0 { 0 } else { 1 }],
);
}
return RXingResultPoint::new(lastX, lastRange[0]);
} else {
return RXingResultPoint::new(lastX, lastRange[1]);
}
}
}
lastRange = range;
y += deltaY;
x += deltaX
}
return Err(NotFoundException.getNotFoundInstance());
}
/**
* Computes the start and end of a region of pixels, either horizontally or vertically, that could
* be part of a Data Matrix barcode.
*
* @param fixedDimension if scanning horizontally, this is the row (the fixed vertical location)
* where we are scanning. If scanning vertically it's the column, the fixed horizontal location
* @param maxWhiteRun largest run of white pixels that can still be considered part of the
* barcode region
* @param minDim minimum pixel location, horizontally or vertically, to consider
* @param maxDim maximum pixel location, horizontally or vertically, to consider
* @param horizontal if true, we're scanning left-right, instead of up-down
* @return int[] with start and end of found range, or null if no such range is found
* (e.g. only white was found)
*/
fn blackWhiteRange(
&self,
fixedDimension: i32,
maxWhiteRun: i32,
minDim: i32,
maxDim: i32,
horizontal: bool,
) -> Option<Vec<i32>> {
let center = (minDim + maxDim) / 2;
// Scan left/up first
let start = center;
while (start >= minDim) {
if (if horizontal {
self.image.get(start, fixedDimension)
} else {
self.image.get(fixedDimension, start)
}) {
start = start - 1;
} else {
let whiteRunStart = start;
start = start - 1;
while start >= minDim
&& !(if horizontal {
self.image.get(start, fixedDimension)
} else {
self.image.get(fixedDimension, start)
})
{
start = start - 1;
}
let whiteRunSize = whiteRunStart - start;
if (start < minDim || whiteRunSize > maxWhiteRun) {
start = whiteRunStart;
break;
}
}
}
start = start + 1;
// Then try right/down
let end = center;
while (end < maxDim) {
if (if horizontal {
self.image.get(end, fixedDimension)
} else {
self.image.get(fixedDimension, end)
}) {
end = end + 1;
} else {
let whiteRunStart = end;
end = end + 1;
while end < maxDim
&& !(if horizontal {
self.image.get(end, fixedDimension)
} else {
self.image.get(fixedDimension, end)
})
{
end = end + 1;
}
let whiteRunSize = end - whiteRunStart;
if (end >= maxDim || whiteRunSize > maxWhiteRun) {
end = whiteRunStart;
break;
}
}
}
end = end - 1;
return if end > start {
Some(vec! {start, end})
} else {
None
};
}
}

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/*
* Copyright 2010 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.detector;
use crate::{NotFoundException,RXingResultPoint};
use crate::common::BitMatrix;
use super::MathUtils;
/**
* <p>
* Detects a candidate barcode-like rectangular region within an image. It
* starts around the center of the image, increases the size of the candidate
* region until it finds a white rectangular region. By keeping track of the
* last black points it encountered, it determines the corners of the barcode.
* </p>
*
* @author David Olivier
*/
const INIT_SIZE:i32 = 10;
const CORR:i32 = 1;
pub struct WhiteRectangleDetector {
image: BitMatrix,
height: i32,
width: i32,
leftInit: i32,
rightInit: i32,
downInit: i32,
upInit: i32,
}
impl WhiteRectangleDetector {
pub fn new_from_image(image:&BitMatrix) -> Result<Self,NotFoundException> {
Self::new(image, INIT_SIZE, image.getWidth() / 2, image.getHeight() / 2)
}
/**
* @param image barcode image to find a rectangle in
* @param initSize initial size of search area around center
* @param x x position of search center
* @param y y position of search center
* @throws NotFoundException if image is too small to accommodate {@code initSize}
*/
pub fn new( image:&BitMatrix, initSize:i32, x:i32, y:i32) -> Result<Self, NotFoundException> {
let new_wrd : Self;
new_wrd.image = image;
new_wrd.height = image.getHeight();
new_wrd.width = image.getWidth();
let halfsize = initSize / 2;
new_wrd.leftInit = x - halfsize;
new_wrd.rightInit = x + halfsize;
new_wrd.upInit = y - halfsize;
new_wrd.downInit = y + halfsize;
if (new_wrd.upInit < 0 || new_wrd.leftInit < 0 || new_wrd.downInit >= new_wrd.height || new_wrd.rightInit >= new_wrd.width) {
return Err( NotFoundException.getNotFoundInstance());
}
Ok(new_wrd)
}
/**
* <p>
* Detects a candidate barcode-like rectangular region within an image. It
* starts around the center of the image, increases the size of the candidate
* region until it finds a white rectangular region.
* </p>
*
* @return {@link RXingResultPoint}[] describing the corners of the rectangular
* region. The first and last points are opposed on the diagonal, as
* are the second and third. The first point will be the topmost
* point and the last, the bottommost. The second point will be
* leftmost and the third, the rightmost
* @throws NotFoundException if no Data Matrix Code can be found
*/
pub fn detect(&self) -> Result<Vec<RXingResultPoint>, NotFoundException> {
let left :i32= self.leftInit;
let right:i32 = self.rightInit;
let up:i32 = self.upInit;
let down:i32 = self.downInit;
let sizeExceeded = false;
let aBlackPointFoundOnBorder = true;
let atLeastOneBlackPointFoundOnRight = false;
let atLeastOneBlackPointFoundOnBottom = false;
let atLeastOneBlackPointFoundOnLeft = false;
let atLeastOneBlackPointFoundOnTop = false;
while (aBlackPointFoundOnBorder) {
aBlackPointFoundOnBorder = false;
// .....
// . |
// .....
let rightBorderNotWhite = true;
while ((rightBorderNotWhite || !atLeastOneBlackPointFoundOnRight) && right < self.width) {
rightBorderNotWhite = self.containsBlackPoint(up, down, right, false);
if (rightBorderNotWhite) {
right += 1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnRight = true;
} else if (!atLeastOneBlackPointFoundOnRight) {
right+=1;
}
}
if (right >= self.width) {
sizeExceeded = true;
break;
}
// .....
// . .
// .___.
let bottomBorderNotWhite = true;
while ((bottomBorderNotWhite || !atLeastOneBlackPointFoundOnBottom) && down < self.height) {
bottomBorderNotWhite = self.containsBlackPoint(left, right, down, true);
if (bottomBorderNotWhite) {
down+=1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnBottom = true;
} else if (!atLeastOneBlackPointFoundOnBottom) {
down+=1;
}
}
if (down >= self.height) {
sizeExceeded = true;
break;
}
// .....
// | .
// .....
let leftBorderNotWhite = true;
while ((leftBorderNotWhite || !atLeastOneBlackPointFoundOnLeft) && left >= 0) {
leftBorderNotWhite = self.containsBlackPoint(up, down, left, false);
if (leftBorderNotWhite) {
left-=1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnLeft = true;
} else if (!atLeastOneBlackPointFoundOnLeft) {
left-=1;
}
}
if (left < 0) {
sizeExceeded = true;
break;
}
// .___.
// . .
// .....
let topBorderNotWhite = true;
while ((topBorderNotWhite || !atLeastOneBlackPointFoundOnTop) && up >= 0) {
topBorderNotWhite = self.containsBlackPoint(left, right, up, true);
if (topBorderNotWhite) {
up-=1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnTop = true;
} else if (!atLeastOneBlackPointFoundOnTop) {
up-=1;
}
}
if (up < 0) {
sizeExceeded = true;
break;
}
}
if (!sizeExceeded) {
let maxSize = right - left;
let mut z: Option<RXingResultPoint> = None;
let mut i = 1;
while z.is_none() && i < maxSize {
//for (int i = 1; z == null && i < maxSize; i++) {
z = self.getBlackPointOnSegment(left, down - i, left + i, down);
i+=1;
}
if (z .is_none()) {
return Err( NotFoundException.getNotFoundInstance());
}
let mut t : Option<RXingResultPoint> = None;
//go down right
let mut i = 1;
while t.is_none() && i < maxSize {
//for (int i = 1; t == null && i < maxSize; i++) {
t = self.getBlackPointOnSegment(left, up + i, left + i, up);
i+=1;
}
if (t .is_none()) {
return Err( NotFoundException.getNotFoundInstance());
}
let mut x : Option<RXingResultPoint> = None;
//go down left
let mut i = 1;
while x.is_none() && i < maxSize {
//for (int i = 1; x == null && i < maxSize; i++) {
x = self.getBlackPointOnSegment(right, up + i, right - i, up);
i += 1;
}
if (x .is_none()) {
return Err( NotFoundException.getNotFoundInstance());
}
let mut y : Option<RXingResultPoint> = None;
//go up left
let mut i = 1;
while y.is_none() && i < maxSize {
//for (int i = 1; y == null && i < maxSize; i++) {
y = self.getBlackPointOnSegment(right, down - i, right - i, down);
i+=1;
}
if (y .is_none()) {
return Err( NotFoundException.getNotFoundInstance());
}
return self.centerEdges(y, z, x, t);
} else {
return Err( NotFoundException.getNotFoundInstance());
}
}
fn getBlackPointOnSegment(&self, aX:f32, aY:f32, bX:f32, bY:f32) -> Option<RXingResultPoint> {
let dist = MathUtils::round(MathUtils::distance_float(aX, aY, bX, bY));
let xStep :f32= (bX - aX) / dist;
let yStep:f32 = (bY - aY) / dist;
for i in 0..dist {
let x = MathUtils::round(aX + i * xStep);
let y = MathUtils::round(aY + i * yStep);
if (self.image.get(x, y)) {
return RXingResultPoint::new(x, y);
}
}
return None;
}
/**
* recenters the points of a constant distance towards the center
*
* @param y bottom most point
* @param z left most point
* @param x right most point
* @param t top most point
* @return {@link RXingResultPoint}[] describing the corners of the rectangular
* region. The first and last points are opposed on the diagonal, as
* are the second and third. The first point will be the topmost
* point and the last, the bottommost. The second point will be
* leftmost and the third, the rightmost
*/
fn centerEdges( &self,y:&RXingResultPoint, z:&RXingResultPoint,
x:&RXingResultPoint, t:&RXingResultPoint) -> Vec<RXingResultPoint> {
//
// t t
// z x
// x OR z
// y y
//
let yi = y.getX();
let yj = y.getY();
let zi = z.getX();
let zj = z.getY();
let xi = x.getX();
let xj = x.getY();
let ti = t.getX();
let tj = t.getY();
if (yi < self.width.into() / 2.0f32) {
return vec!
[ RXingResultPoint::new(ti - CORR, tj + CORR),
RXingResultPoint::new(zi + CORR, zj + CORR),
RXingResultPoint::new(xi - CORR, xj - CORR),
RXingResultPoint::new(yi + CORR, yj - CORR)];
} else {
return vec![
RXingResultPoint::new(ti + CORR, tj + CORR),
RXingResultPoint::new(zi + CORR, zj - CORR),
RXingResultPoint::new(xi - CORR, xj + CORR),
RXingResultPoint::new(yi - CORR, yj - CORR)];
}
}
/**
* Determines whether a segment contains a black point
*
* @param a min value of the scanned coordinate
* @param b max value of the scanned coordinate
* @param fixed value of fixed coordinate
* @param horizontal set to true if scan must be horizontal, false if vertical
* @return true if a black point has been found, else false.
*/
fn containsBlackPoint(&self, a:i32, b:i32, fixed:i32, horizontal:bool) -> bool {
if (horizontal) {
for x in a..=b {
if (self.image.get(x, fixed)) {
return true;
}
}
} else {
for y in a..=b {
if (self.image.get(fixed, y)) {
return true;
}
}
}
return false;
}
}

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mod MonochromeRectangleDetector;
mod WhiteRectangleDetector;
pub mod MathUtils;
pub use MonochromeRectangleDetector::*;
pub use WhiteRectangleDetector::*;
/*
* 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.detector;
use crate::common::BitMatrix;
use crate::{NotFoundException, RXingResultPoint};
/**
* <p>A somewhat generic detector that looks for a barcode-like rectangular region within an image.
* It looks within a mostly white region of an image for a region of black and white, but mostly
* black. It returns the four corners of the region, as best it can determine.</p>
*
* @author Sean Owen
* @deprecated without replacement since 3.3.0
*/
const MAX_MODULES: i32 = 32;
#[deprecated]
pub struct MonochromeRectangleDetector {
image: BitMatrix,
}
impl MonochromeRectangleDetector {
pub fn new(image: &BitMatrix) -> Self {
Self { image: image }
}
/**
* <p>Detects a rectangular region of black and white -- mostly black -- with a region of mostly
* white, in an image.</p>
*
* @return {@link RXingResultPoint}[] describing the corners of the rectangular region. The first and
* last points are opposed on the diagonal, as are the second and third. The first point will be
* the topmost point and the last, the bottommost. The second point will be leftmost and the
* third, the rightmost
* @throws NotFoundException if no Data Matrix Code can be found
*/
pub fn detect(&self) -> Result<Vec<RXingResultPoint>, NotFoundException> {
let height = self.image.getHeight();
let width = self.image.getWidth();
let halfHeight = height / 2;
let halfWidth = width / 2;
let deltaY = 1.max(height / (MAX_MODULES * 8));
let deltaX = 1.max(width / (MAX_MODULES * 8));
let top = 0;
let bottom = height;
let left = 0;
let right = width;
let pointA = self.findCornerFromCenter(
halfWidth,
0,
left,
right,
halfHeight,
-deltaY,
top,
bottom,
halfWidth / 2,
)?;
top = pointA.getY() - 1;
let pointB = self.findCornerFromCenter(
halfWidth,
-deltaX,
left,
right,
halfHeight,
0,
top,
bottom,
halfHeight / 2,
)?;
left = pointB.getX() - 1;
let pointC = self.findCornerFromCenter(
halfWidth,
deltaX,
left,
right,
halfHeight,
0,
top,
bottom,
halfHeight / 2,
)?;
right = pointC.getX() + 1;
let pointD = self.findCornerFromCenter(
halfWidth,
0,
left,
right,
halfHeight,
deltaY,
top,
bottom,
halfWidth / 2,
)?;
bottom = pointD.getY() + 1;
// Go try to find point A again with better information -- might have been off at first.
pointA = self.findCornerFromCenter(
halfWidth,
0,
left,
right,
halfHeight,
-deltaY,
top,
bottom,
halfWidth / 4,
)?;
return Ok(vec![[pointA, pointB, pointC, pointD]]);
}
/**
* Attempts to locate a corner of the barcode by scanning up, down, left or right from a center
* point which should be within the barcode.
*
* @param centerX center's x component (horizontal)
* @param deltaX same as deltaY but change in x per step instead
* @param left minimum value of x
* @param right maximum value of x
* @param centerY center's y component (vertical)
* @param deltaY change in y per step. If scanning up this is negative; down, positive;
* left or right, 0
* @param top minimum value of y to search through (meaningless when di == 0)
* @param bottom maximum value of y
* @param maxWhiteRun maximum run of white pixels that can still be considered to be within
* the barcode
* @return a {@link RXingResultPoint} encapsulating the corner that was found
* @throws NotFoundException if such a point cannot be found
*/
fn findCornerFromCenter(
&self,
centerX: i32,
deltaX: i32,
left: i32,
right: i32,
centerY: i32,
deltaY: i32,
top: i32,
bottom: i32,
maxWhiteRun: i32,
) -> Result<RXingResultPoint, NotFoundException> {
let lastRange: Option<Vec<i32>> = None;
let y: i32 = centerY;
let x: i32 = centerX;
while (y < bottom && y >= top && x < right && x >= left) {
let range: Option<Vec<i32>>;
if (deltaX == 0) {
// horizontal slices, up and down
range = self.blackWhiteRange(y, maxWhiteRun, left, right, true);
} else {
// vertical slices, left and right
range = self.blackWhiteRange(x, maxWhiteRun, top, bottom, false);
}
if (range.is_none()) {
if (lastRange.is_none()) {
return Err(NotFoundException {});
}
// lastRange was found
if (deltaX == 0) {
let lastY = y - deltaY;
if (lastRange?[0] < centerX) {
if (lastRange?[1] > centerX) {
// straddle, choose one or the other based on direction
return RXingResultPoint::new(
lastRange?[if deltaY > 0 { 0 } else { 1 }],
lastY,
);
}
return RXingResultPoint::new(lastRange?[0], lastY);
} else {
return RXingResultPoint::new(lastRange?[1], lastY);
}
} else {
let lastX = x - deltaX;
if (lastRange?[0] < centerY) {
if (lastRange?[1] > centerY) {
return RXingResultPoint::new(
lastX,
lastRange?[if deltaX < 0 { 0 } else { 1 }],
);
}
return RXingResultPoint::new(lastX, lastRange?[0]);
} else {
return RXingResultPoint::new(lastX, lastRange?[1]);
}
}
}
lastRange = range;
y += deltaY;
x += deltaX
}
return Err(NotFoundException {});
}
/**
* Computes the start and end of a region of pixels, either horizontally or vertically, that could
* be part of a Data Matrix barcode.
*
* @param fixedDimension if scanning horizontally, this is the row (the fixed vertical location)
* where we are scanning. If scanning vertically it's the column, the fixed horizontal location
* @param maxWhiteRun largest run of white pixels that can still be considered part of the
* barcode region
* @param minDim minimum pixel location, horizontally or vertically, to consider
* @param maxDim maximum pixel location, horizontally or vertically, to consider
* @param horizontal if true, we're scanning left-right, instead of up-down
* @return int[] with start and end of found range, or null if no such range is found
* (e.g. only white was found)
*/
fn blackWhiteRange(
&self,
fixedDimension: i32,
maxWhiteRun: i32,
minDim: i32,
maxDim: i32,
horizontal: bool,
) -> Option<Vec<i32>> {
let center = (minDim + maxDim) / 2;
// Scan left/up first
let start = center;
while (start >= minDim) {
if (if horizontal {
self.image.get(start, fixedDimension)
} else {
self.image.get(fixedDimension, start)
}) {
start = start - 1;
} else {
let whiteRunStart = start;
start = start - 1;
while start >= minDim
&& !(if horizontal {
self.image.get(start, fixedDimension)
} else {
self.image.get(fixedDimension, start)
})
{
start = start - 1;
}
let whiteRunSize = whiteRunStart - start;
if (start < minDim || whiteRunSize > maxWhiteRun) {
start = whiteRunStart;
break;
}
}
}
start = start + 1;
// Then try right/down
let end = center;
while (end < maxDim) {
if (if horizontal {
self.image.get(end, fixedDimension)
} else {
self.image.get(fixedDimension, end)
}) {
end = end + 1;
} else {
let whiteRunStart = end;
end = end + 1;
while end < maxDim
&& !(if horizontal {
self.image.get(end, fixedDimension)
} else {
self.image.get(fixedDimension, end)
})
{
end = end + 1;
}
let whiteRunSize = end - whiteRunStart;
if (end >= maxDim || whiteRunSize > maxWhiteRun) {
end = whiteRunStart;
break;
}
}
}
end = end - 1;
return if end > start {
Some(vec![start, end])
} else {
None
};
}
}
/*
* Copyright 2010 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.detector;
use crate::common::BitMatrix;
use crate::{NotFoundException, RXingResultPoint};
use super::MathUtils;
/**
* <p>
* Detects a candidate barcode-like rectangular region within an image. It
* starts around the center of the image, increases the size of the candidate
* region until it finds a white rectangular region. By keeping track of the
* last black points it encountered, it determines the corners of the barcode.
* </p>
*
* @author David Olivier
*/
const INIT_SIZE: i32 = 10;
const CORR: i32 = 1;
pub struct WhiteRectangleDetector {
image: BitMatrix,
height: i32,
width: i32,
leftInit: i32,
rightInit: i32,
downInit: i32,
upInit: i32,
}
impl WhiteRectangleDetector {
pub fn new_from_image(image: &BitMatrix) -> Result<Self, NotFoundException> {
Self::new(
image,
INIT_SIZE,
image.getWidth() / 2,
image.getHeight() / 2,
)
}
/**
* @param image barcode image to find a rectangle in
* @param initSize initial size of search area around center
* @param x x position of search center
* @param y y position of search center
* @throws NotFoundException if image is too small to accommodate {@code initSize}
*/
pub fn new(
image: &BitMatrix,
initSize: i32,
x: i32,
y: i32,
) -> Result<Self, NotFoundException> {
let new_wrd: Self;
new_wrd.image = image;
new_wrd.height = image.getHeight();
new_wrd.width = image.getWidth();
let halfsize = initSize / 2;
new_wrd.leftInit = x - halfsize;
new_wrd.rightInit = x + halfsize;
new_wrd.upInit = y - halfsize;
new_wrd.downInit = y + halfsize;
if (new_wrd.upInit < 0
|| new_wrd.leftInit < 0
|| new_wrd.downInit >= new_wrd.height
|| new_wrd.rightInit >= new_wrd.width)
{
return Err(NotFoundException {});
}
Ok(new_wrd)
}
/**
* <p>
* Detects a candidate barcode-like rectangular region within an image. It
* starts around the center of the image, increases the size of the candidate
* region until it finds a white rectangular region.
* </p>
*
* @return {@link RXingResultPoint}[] describing the corners of the rectangular
* region. The first and last points are opposed on the diagonal, as
* are the second and third. The first point will be the topmost
* point and the last, the bottommost. The second point will be
* leftmost and the third, the rightmost
* @throws NotFoundException if no Data Matrix Code can be found
*/
pub fn detect(&self) -> Result<Vec<RXingResultPoint>, NotFoundException> {
let left: i32 = self.leftInit;
let right: i32 = self.rightInit;
let up: i32 = self.upInit;
let down: i32 = self.downInit;
let sizeExceeded = false;
let aBlackPointFoundOnBorder = true;
let atLeastOneBlackPointFoundOnRight = false;
let atLeastOneBlackPointFoundOnBottom = false;
let atLeastOneBlackPointFoundOnLeft = false;
let atLeastOneBlackPointFoundOnTop = false;
while (aBlackPointFoundOnBorder) {
aBlackPointFoundOnBorder = false;
// .....
// . |
// .....
let rightBorderNotWhite = true;
while ((rightBorderNotWhite || !atLeastOneBlackPointFoundOnRight) && right < self.width)
{
rightBorderNotWhite = self.containsBlackPoint(up, down, right, false);
if (rightBorderNotWhite) {
right += 1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnRight = true;
} else if (!atLeastOneBlackPointFoundOnRight) {
right += 1;
}
}
if (right >= self.width) {
sizeExceeded = true;
break;
}
// .....
// . .
// .___.
let bottomBorderNotWhite = true;
while ((bottomBorderNotWhite || !atLeastOneBlackPointFoundOnBottom)
&& down < self.height)
{
bottomBorderNotWhite = self.containsBlackPoint(left, right, down, true);
if (bottomBorderNotWhite) {
down += 1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnBottom = true;
} else if (!atLeastOneBlackPointFoundOnBottom) {
down += 1;
}
}
if (down >= self.height) {
sizeExceeded = true;
break;
}
// .....
// | .
// .....
let leftBorderNotWhite = true;
while ((leftBorderNotWhite || !atLeastOneBlackPointFoundOnLeft) && left >= 0) {
leftBorderNotWhite = self.containsBlackPoint(up, down, left, false);
if (leftBorderNotWhite) {
left -= 1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnLeft = true;
} else if (!atLeastOneBlackPointFoundOnLeft) {
left -= 1;
}
}
if (left < 0) {
sizeExceeded = true;
break;
}
// .___.
// . .
// .....
let topBorderNotWhite = true;
while ((topBorderNotWhite || !atLeastOneBlackPointFoundOnTop) && up >= 0) {
topBorderNotWhite = self.containsBlackPoint(left, right, up, true);
if (topBorderNotWhite) {
up -= 1;
aBlackPointFoundOnBorder = true;
atLeastOneBlackPointFoundOnTop = true;
} else if (!atLeastOneBlackPointFoundOnTop) {
up -= 1;
}
}
if (up < 0) {
sizeExceeded = true;
break;
}
}
if (!sizeExceeded) {
let maxSize = right - left;
let mut z: Option<RXingResultPoint> = None;
let mut i = 1;
while z.is_none() && i < maxSize {
//for (int i = 1; z == null && i < maxSize; i++) {
z = self.getBlackPointOnSegment(left, down - i, left + i, down);
i += 1;
}
if (z.is_none()) {
return Err(NotFoundException {});
}
let mut t: Option<RXingResultPoint> = None;
//go down right
let mut i = 1;
while t.is_none() && i < maxSize {
//for (int i = 1; t == null && i < maxSize; i++) {
t = self.getBlackPointOnSegment(left, up + i, left + i, up);
i += 1;
}
if (t.is_none()) {
return Err(NotFoundException {});
}
let mut x: Option<RXingResultPoint> = None;
//go down left
let mut i = 1;
while x.is_none() && i < maxSize {
//for (int i = 1; x == null && i < maxSize; i++) {
x = self.getBlackPointOnSegment(right, up + i, right - i, up);
i += 1;
}
if (x.is_none()) {
return Err(NotFoundException {});
}
let mut y: Option<RXingResultPoint> = None;
//go up left
let mut i = 1;
while y.is_none() && i < maxSize {
//for (int i = 1; y == null && i < maxSize; i++) {
y = self.getBlackPointOnSegment(right, down - i, right - i, down);
i += 1;
}
if (y.is_none()) {
return Err(NotFoundException {});
}
return Ok(self.centerEdges(y.unwrap(), z.unwrap(), x.unwrap(), t.unwrap()));
} else {
return Err(NotFoundException {});
}
}
fn getBlackPointOnSegment(
&self,
aX: f32,
aY: f32,
bX: f32,
bY: f32,
) -> Option<RXingResultPoint> {
let dist = MathUtils::round(MathUtils::distance_float(aX, aY, bX, bY));
let xStep: f32 = (bX - aX) / dist.into();
let yStep: f32 = (bY - aY) / dist.into();
for i in 0..dist {
let x = MathUtils::round(aX + i.into() * xStep);
let y = MathUtils::round(aY + i.into() * yStep);
if (self.image.get(x, y)) {
return RXingResultPoint::new(x, y);
}
}
return None;
}
/**
* recenters the points of a constant distance towards the center
*
* @param y bottom most point
* @param z left most point
* @param x right most point
* @param t top most point
* @return {@link RXingResultPoint}[] describing the corners of the rectangular
* region. The first and last points are opposed on the diagonal, as
* are the second and third. The first point will be the topmost
* point and the last, the bottommost. The second point will be
* leftmost and the third, the rightmost
*/
fn centerEdges(
&self,
y: &RXingResultPoint,
z: &RXingResultPoint,
x: &RXingResultPoint,
t: &RXingResultPoint,
) -> Vec<RXingResultPoint> {
//
// t t
// z x
// x OR z
// y y
//
let yi = y.getX();
let yj = y.getY();
let zi = z.getX();
let zj = z.getY();
let xi = x.getX();
let xj = x.getY();
let ti = t.getX();
let tj = t.getY();
if (yi < self.width.into() / 2.0f32) {
return vec![
RXingResultPoint::new(ti - CORR, tj + CORR),
RXingResultPoint::new(zi + CORR, zj + CORR),
RXingResultPoint::new(xi - CORR, xj - CORR),
RXingResultPoint::new(yi + CORR, yj - CORR),
];
} else {
return vec![
RXingResultPoint::new(ti + CORR, tj + CORR),
RXingResultPoint::new(zi + CORR, zj - CORR),
RXingResultPoint::new(xi - CORR, xj + CORR),
RXingResultPoint::new(yi - CORR, yj - CORR),
];
}
}
/**
* Determines whether a segment contains a black point
*
* @param a min value of the scanned coordinate
* @param b max value of the scanned coordinate
* @param fixed value of fixed coordinate
* @param horizontal set to true if scan must be horizontal, false if vertical
* @return true if a black point has been found, else false.
*/
fn containsBlackPoint(&self, a: i32, b: i32, fixed: i32, horizontal: bool) -> bool {
if (horizontal) {
for x in a..=b {
if (self.image.get(x, fixed)) {
return true;
}
}
} else {
for y in a..=b {
if (self.image.get(fixed, y)) {
return true;
}
}
}
return false;
}
}

View File

@@ -1,166 +0,0 @@
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>This class contains utility methods for performing mathematical operations over
* the Galois Fields. Operations use a given primitive polynomial in calculations.</p>
*
* <p>Throughout this package, elements of the GF are represented as an {@code int}
* for convenience and speed (but at the cost of memory).
* </p>
*
* @author Sean Owen
* @author David Olivier
*/
public final class GenericGF {
public static final GenericGF AZTEC_DATA_12 = new GenericGF(0x1069, 4096, 1); // x^12 + x^6 + x^5 + x^3 + 1
public static final GenericGF AZTEC_DATA_10 = new GenericGF(0x409, 1024, 1); // x^10 + x^3 + 1
public static final GenericGF AZTEC_DATA_6 = new GenericGF(0x43, 64, 1); // x^6 + x + 1
public static final GenericGF AZTEC_PARAM = new GenericGF(0x13, 16, 1); // x^4 + x + 1
public static final GenericGF QR_CODE_FIELD_256 = new GenericGF(0x011D, 256, 0); // x^8 + x^4 + x^3 + x^2 + 1
public static final GenericGF DATA_MATRIX_FIELD_256 = new GenericGF(0x012D, 256, 1); // x^8 + x^5 + x^3 + x^2 + 1
public static final GenericGF AZTEC_DATA_8 = DATA_MATRIX_FIELD_256;
public static final GenericGF MAXICODE_FIELD_64 = AZTEC_DATA_6;
private final int[] expTable;
private final int[] logTable;
private final GenericGFPoly zero;
private final GenericGFPoly one;
private final int size;
private final int primitive;
private final int generatorBase;
/**
* Create a representation of GF(size) using the given primitive polynomial.
*
* @param primitive irreducible polynomial whose coefficients are represented by
* the bits of an int, where the least-significant bit represents the constant
* coefficient
* @param size the size of the field
* @param b the factor b in the generator polynomial can be 0- or 1-based
* (g(x) = (x+a^b)(x+a^(b+1))...(x+a^(b+2t-1))).
* In most cases it should be 1, but for QR code it is 0.
*/
public GenericGF(int primitive, int size, int b) {
this.primitive = primitive;
this.size = size;
this.generatorBase = b;
expTable = new int[size];
logTable = new int[size];
int x = 1;
for (int i = 0; i < size; i++) {
expTable[i] = x;
x *= 2; // we're assuming the generator alpha is 2
if (x >= size) {
x ^= primitive;
x &= size - 1;
}
}
for (int i = 0; i < size - 1; i++) {
logTable[expTable[i]] = i;
}
// logTable[0] == 0 but this should never be used
zero = new GenericGFPoly(this, new int[]{0});
one = new GenericGFPoly(this, new int[]{1});
}
GenericGFPoly getZero() {
return zero;
}
GenericGFPoly getOne() {
return one;
}
/**
* @return the monomial representing coefficient * x^degree
*/
GenericGFPoly buildMonomial(int degree, int coefficient) {
if (degree < 0) {
throw new IllegalArgumentException();
}
if (coefficient == 0) {
return zero;
}
int[] coefficients = new int[degree + 1];
coefficients[0] = coefficient;
return new GenericGFPoly(this, coefficients);
}
/**
* Implements both addition and subtraction -- they are the same in GF(size).
*
* @return sum/difference of a and b
*/
static int addOrSubtract(int a, int b) {
return a ^ b;
}
/**
* @return 2 to the power of a in GF(size)
*/
int exp(int a) {
return expTable[a];
}
/**
* @return base 2 log of a in GF(size)
*/
int log(int a) {
if (a == 0) {
throw new IllegalArgumentException();
}
return logTable[a];
}
/**
* @return multiplicative inverse of a
*/
int inverse(int a) {
if (a == 0) {
throw new ArithmeticException();
}
return expTable[size - logTable[a] - 1];
}
/**
* @return product of a and b in GF(size)
*/
int multiply(int a, int b) {
if (a == 0 || b == 0) {
return 0;
}
return expTable[(logTable[a] + logTable[b]) % (size - 1)];
}
public int getSize() {
return size;
}
public int getGeneratorBase() {
return generatorBase;
}
@Override
public String toString() {
return "GF(0x" + Integer.toHexString(primitive) + ',' + size + ')';
}
}

View File

@@ -1,271 +0,0 @@
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>Represents a polynomial whose coefficients are elements of a GF.
* Instances of this class are immutable.</p>
*
* <p>Much credit is due to William Rucklidge since portions of this code are an indirect
* port of his C++ Reed-Solomon implementation.</p>
*
* @author Sean Owen
*/
final class GenericGFPoly {
private final GenericGF field;
private final int[] coefficients;
/**
* @param field the {@link GenericGF} instance representing the field to use
* to perform computations
* @param coefficients coefficients as ints representing elements of GF(size), arranged
* from most significant (highest-power term) coefficient to least significant
* @throws IllegalArgumentException if argument is null or empty,
* or if leading coefficient is 0 and this is not a
* constant polynomial (that is, it is not the monomial "0")
*/
GenericGFPoly(GenericGF field, int[] coefficients) {
if (coefficients.length == 0) {
throw new IllegalArgumentException();
}
this.field = field;
int coefficientsLength = coefficients.length;
if (coefficientsLength > 1 && coefficients[0] == 0) {
// Leading term must be non-zero for anything except the constant polynomial "0"
int firstNonZero = 1;
while (firstNonZero < coefficientsLength && coefficients[firstNonZero] == 0) {
firstNonZero++;
}
if (firstNonZero == coefficientsLength) {
this.coefficients = new int[]{0};
} else {
this.coefficients = new int[coefficientsLength - firstNonZero];
System.arraycopy(coefficients,
firstNonZero,
this.coefficients,
0,
this.coefficients.length);
}
} else {
this.coefficients = coefficients;
}
}
int[] getCoefficients() {
return coefficients;
}
/**
* @return degree of this polynomial
*/
int getDegree() {
return coefficients.length - 1;
}
/**
* @return true iff this polynomial is the monomial "0"
*/
boolean isZero() {
return coefficients[0] == 0;
}
/**
* @return coefficient of x^degree term in this polynomial
*/
int getCoefficient(int degree) {
return coefficients[coefficients.length - 1 - degree];
}
/**
* @return evaluation of this polynomial at a given point
*/
int evaluateAt(int a) {
if (a == 0) {
// Just return the x^0 coefficient
return getCoefficient(0);
}
if (a == 1) {
// Just the sum of the coefficients
int result = 0;
for (int coefficient : coefficients) {
result = GenericGF.addOrSubtract(result, coefficient);
}
return result;
}
int result = coefficients[0];
int size = coefficients.length;
for (int i = 1; i < size; i++) {
result = GenericGF.addOrSubtract(field.multiply(a, result), coefficients[i]);
}
return result;
}
GenericGFPoly addOrSubtract(GenericGFPoly other) {
if (!field.equals(other.field)) {
throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
}
if (isZero()) {
return other;
}
if (other.isZero()) {
return this;
}
int[] smallerCoefficients = this.coefficients;
int[] largerCoefficients = other.coefficients;
if (smallerCoefficients.length > largerCoefficients.length) {
int[] temp = smallerCoefficients;
smallerCoefficients = largerCoefficients;
largerCoefficients = temp;
}
int[] sumDiff = new int[largerCoefficients.length];
int lengthDiff = largerCoefficients.length - smallerCoefficients.length;
// Copy high-order terms only found in higher-degree polynomial's coefficients
System.arraycopy(largerCoefficients, 0, sumDiff, 0, lengthDiff);
for (int i = lengthDiff; i < largerCoefficients.length; i++) {
sumDiff[i] = GenericGF.addOrSubtract(smallerCoefficients[i - lengthDiff], largerCoefficients[i]);
}
return new GenericGFPoly(field, sumDiff);
}
GenericGFPoly multiply(GenericGFPoly other) {
if (!field.equals(other.field)) {
throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
}
if (isZero() || other.isZero()) {
return field.getZero();
}
int[] aCoefficients = this.coefficients;
int aLength = aCoefficients.length;
int[] bCoefficients = other.coefficients;
int bLength = bCoefficients.length;
int[] product = new int[aLength + bLength - 1];
for (int i = 0; i < aLength; i++) {
int aCoeff = aCoefficients[i];
for (int j = 0; j < bLength; j++) {
product[i + j] = GenericGF.addOrSubtract(product[i + j],
field.multiply(aCoeff, bCoefficients[j]));
}
}
return new GenericGFPoly(field, product);
}
GenericGFPoly multiply(int scalar) {
if (scalar == 0) {
return field.getZero();
}
if (scalar == 1) {
return this;
}
int size = coefficients.length;
int[] product = new int[size];
for (int i = 0; i < size; i++) {
product[i] = field.multiply(coefficients[i], scalar);
}
return new GenericGFPoly(field, product);
}
GenericGFPoly multiplyByMonomial(int degree, int coefficient) {
if (degree < 0) {
throw new IllegalArgumentException();
}
if (coefficient == 0) {
return field.getZero();
}
int size = coefficients.length;
int[] product = new int[size + degree];
for (int i = 0; i < size; i++) {
product[i] = field.multiply(coefficients[i], coefficient);
}
return new GenericGFPoly(field, product);
}
GenericGFPoly[] divide(GenericGFPoly other) {
if (!field.equals(other.field)) {
throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
}
if (other.isZero()) {
throw new IllegalArgumentException("Divide by 0");
}
GenericGFPoly quotient = field.getZero();
GenericGFPoly remainder = this;
int denominatorLeadingTerm = other.getCoefficient(other.getDegree());
int inverseDenominatorLeadingTerm = field.inverse(denominatorLeadingTerm);
while (remainder.getDegree() >= other.getDegree() && !remainder.isZero()) {
int degreeDifference = remainder.getDegree() - other.getDegree();
int scale = field.multiply(remainder.getCoefficient(remainder.getDegree()), inverseDenominatorLeadingTerm);
GenericGFPoly term = other.multiplyByMonomial(degreeDifference, scale);
GenericGFPoly iterationQuotient = field.buildMonomial(degreeDifference, scale);
quotient = quotient.addOrSubtract(iterationQuotient);
remainder = remainder.addOrSubtract(term);
}
return new GenericGFPoly[] { quotient, remainder };
}
@Override
public String toString() {
if (isZero()) {
return "0";
}
StringBuilder result = new StringBuilder(8 * getDegree());
for (int degree = getDegree(); degree >= 0; degree--) {
int coefficient = getCoefficient(degree);
if (coefficient != 0) {
if (coefficient < 0) {
if (degree == getDegree()) {
result.append("-");
} else {
result.append(" - ");
}
coefficient = -coefficient;
} else {
if (result.length() > 0) {
result.append(" + ");
}
}
if (degree == 0 || coefficient != 1) {
int alphaPower = field.log(coefficient);
if (alphaPower == 0) {
result.append('1');
} else if (alphaPower == 1) {
result.append('a');
} else {
result.append("a^");
result.append(alphaPower);
}
}
if (degree != 0) {
if (degree == 1) {
result.append('x');
} else {
result.append("x^");
result.append(degree);
}
}
}
}
return result.toString();
}
}

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@@ -1,191 +0,0 @@
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>Implements Reed-Solomon decoding, as the name implies.</p>
*
* <p>The algorithm will not be explained here, but the following references were helpful
* in creating this implementation:</p>
*
* <ul>
* <li>Bruce Maggs.
* <a href="http://www.cs.cmu.edu/afs/cs.cmu.edu/project/pscico-guyb/realworld/www/rs_decode.ps">
* "Decoding Reed-Solomon Codes"</a> (see discussion of Forney's Formula)</li>
* <li>J.I. Hall. <a href="www.mth.msu.edu/~jhall/classes/codenotes/GRS.pdf">
* "Chapter 5. Generalized Reed-Solomon Codes"</a>
* (see discussion of Euclidean algorithm)</li>
* </ul>
*
* <p>Much credit is due to William Rucklidge since portions of this code are an indirect
* port of his C++ Reed-Solomon implementation.</p>
*
* @author Sean Owen
* @author William Rucklidge
* @author sanfordsquires
*/
public final class ReedSolomonDecoder {
private final GenericGF field;
public ReedSolomonDecoder(GenericGF field) {
this.field = field;
}
/**
* <p>Decodes given set of received codewords, which include both data and error-correction
* codewords. Really, this means it uses Reed-Solomon to detect and correct errors, in-place,
* in the input.</p>
*
* @param received data and error-correction codewords
* @param twoS number of error-correction codewords available
* @throws ReedSolomonException if decoding fails for any reason
*/
public void decode(int[] received, int twoS) throws ReedSolomonException {
GenericGFPoly poly = new GenericGFPoly(field, received);
int[] syndromeCoefficients = new int[twoS];
boolean noError = true;
for (int i = 0; i < twoS; i++) {
int eval = poly.evaluateAt(field.exp(i + field.getGeneratorBase()));
syndromeCoefficients[syndromeCoefficients.length - 1 - i] = eval;
if (eval != 0) {
noError = false;
}
}
if (noError) {
return;
}
GenericGFPoly syndrome = new GenericGFPoly(field, syndromeCoefficients);
GenericGFPoly[] sigmaOmega =
runEuclideanAlgorithm(field.buildMonomial(twoS, 1), syndrome, twoS);
GenericGFPoly sigma = sigmaOmega[0];
GenericGFPoly omega = sigmaOmega[1];
int[] errorLocations = findErrorLocations(sigma);
int[] errorMagnitudes = findErrorMagnitudes(omega, errorLocations);
for (int i = 0; i < errorLocations.length; i++) {
int position = received.length - 1 - field.log(errorLocations[i]);
if (position < 0) {
throw new ReedSolomonException("Bad error location");
}
received[position] = GenericGF.addOrSubtract(received[position], errorMagnitudes[i]);
}
}
private GenericGFPoly[] runEuclideanAlgorithm(GenericGFPoly a, GenericGFPoly b, int R)
throws ReedSolomonException {
// Assume a's degree is >= b's
if (a.getDegree() < b.getDegree()) {
GenericGFPoly temp = a;
a = b;
b = temp;
}
GenericGFPoly rLast = a;
GenericGFPoly r = b;
GenericGFPoly tLast = field.getZero();
GenericGFPoly t = field.getOne();
// Run Euclidean algorithm until r's degree is less than R/2
while (2 * r.getDegree() >= R) {
GenericGFPoly rLastLast = rLast;
GenericGFPoly tLastLast = tLast;
rLast = r;
tLast = t;
// Divide rLastLast by rLast, with quotient in q and remainder in r
if (rLast.isZero()) {
// Oops, Euclidean algorithm already terminated?
throw new ReedSolomonException("r_{i-1} was zero");
}
r = rLastLast;
GenericGFPoly q = field.getZero();
int denominatorLeadingTerm = rLast.getCoefficient(rLast.getDegree());
int dltInverse = field.inverse(denominatorLeadingTerm);
while (r.getDegree() >= rLast.getDegree() && !r.isZero()) {
int degreeDiff = r.getDegree() - rLast.getDegree();
int scale = field.multiply(r.getCoefficient(r.getDegree()), dltInverse);
q = q.addOrSubtract(field.buildMonomial(degreeDiff, scale));
r = r.addOrSubtract(rLast.multiplyByMonomial(degreeDiff, scale));
}
t = q.multiply(tLast).addOrSubtract(tLastLast);
if (r.getDegree() >= rLast.getDegree()) {
throw new IllegalStateException("Division algorithm failed to reduce polynomial? " +
"r: " + r + ", rLast: " + rLast);
}
}
int sigmaTildeAtZero = t.getCoefficient(0);
if (sigmaTildeAtZero == 0) {
throw new ReedSolomonException("sigmaTilde(0) was zero");
}
int inverse = field.inverse(sigmaTildeAtZero);
GenericGFPoly sigma = t.multiply(inverse);
GenericGFPoly omega = r.multiply(inverse);
return new GenericGFPoly[]{sigma, omega};
}
private int[] findErrorLocations(GenericGFPoly errorLocator) throws ReedSolomonException {
// This is a direct application of Chien's search
int numErrors = errorLocator.getDegree();
if (numErrors == 1) { // shortcut
return new int[] { errorLocator.getCoefficient(1) };
}
int[] result = new int[numErrors];
int e = 0;
for (int i = 1; i < field.getSize() && e < numErrors; i++) {
if (errorLocator.evaluateAt(i) == 0) {
result[e] = field.inverse(i);
e++;
}
}
if (e != numErrors) {
throw new ReedSolomonException("Error locator degree does not match number of roots");
}
return result;
}
private int[] findErrorMagnitudes(GenericGFPoly errorEvaluator, int[] errorLocations) {
// This is directly applying Forney's Formula
int s = errorLocations.length;
int[] result = new int[s];
for (int i = 0; i < s; i++) {
int xiInverse = field.inverse(errorLocations[i]);
int denominator = 1;
for (int j = 0; j < s; j++) {
if (i != j) {
//denominator = field.multiply(denominator,
// GenericGF.addOrSubtract(1, field.multiply(errorLocations[j], xiInverse)));
// Above should work but fails on some Apple and Linux JDKs due to a Hotspot bug.
// Below is a funny-looking workaround from Steven Parkes
int term = field.multiply(errorLocations[j], xiInverse);
int termPlus1 = (term & 0x1) == 0 ? term | 1 : term & ~1;
denominator = field.multiply(denominator, termPlus1);
}
}
result[i] = field.multiply(errorEvaluator.evaluateAt(xiInverse),
field.inverse(denominator));
if (field.getGeneratorBase() != 0) {
result[i] = field.multiply(result[i], xiInverse);
}
}
return result;
}
}

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@@ -1,74 +0,0 @@
/*
* Copyright 2008 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.reedsolomon;
import java.util.ArrayList;
import java.util.List;
/**
* <p>Implements Reed-Solomon encoding, as the name implies.</p>
*
* @author Sean Owen
* @author William Rucklidge
*/
public final class ReedSolomonEncoder {
private final GenericGF field;
private final List<GenericGFPoly> cachedGenerators;
public ReedSolomonEncoder(GenericGF field) {
this.field = field;
this.cachedGenerators = new ArrayList<>();
cachedGenerators.add(new GenericGFPoly(field, new int[]{1}));
}
private GenericGFPoly buildGenerator(int degree) {
if (degree >= cachedGenerators.size()) {
GenericGFPoly lastGenerator = cachedGenerators.get(cachedGenerators.size() - 1);
for (int d = cachedGenerators.size(); d <= degree; d++) {
GenericGFPoly nextGenerator = lastGenerator.multiply(
new GenericGFPoly(field, new int[] { 1, field.exp(d - 1 + field.getGeneratorBase()) }));
cachedGenerators.add(nextGenerator);
lastGenerator = nextGenerator;
}
}
return cachedGenerators.get(degree);
}
public void encode(int[] toEncode, int ecBytes) {
if (ecBytes == 0) {
throw new IllegalArgumentException("No error correction bytes");
}
int dataBytes = toEncode.length - ecBytes;
if (dataBytes <= 0) {
throw new IllegalArgumentException("No data bytes provided");
}
GenericGFPoly generator = buildGenerator(ecBytes);
int[] infoCoefficients = new int[dataBytes];
System.arraycopy(toEncode, 0, infoCoefficients, 0, dataBytes);
GenericGFPoly info = new GenericGFPoly(field, infoCoefficients);
info = info.multiplyByMonomial(ecBytes, 1);
GenericGFPoly remainder = info.divide(generator)[1];
int[] coefficients = remainder.getCoefficients();
int numZeroCoefficients = ecBytes - coefficients.length;
for (int i = 0; i < numZeroCoefficients; i++) {
toEncode[dataBytes + i] = 0;
}
System.arraycopy(coefficients, 0, toEncode, dataBytes + numZeroCoefficients, coefficients.length);
}
}

View File

@@ -1,31 +0,0 @@
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>Thrown when an exception occurs during Reed-Solomon decoding, such as when
* there are too many errors to correct.</p>
*
* @author Sean Owen
*/
public final class ReedSolomonException extends Exception {
public ReedSolomonException(String message) {
super(message);
}
}

View File

@@ -0,0 +1,744 @@
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>Thrown when an exception occurs during Reed-Solomon decoding, such as when
* there are too many errors to correct.</p>
*
* @author Sean Owen
*/
pub struct ReedSolomonException {
message: String,
}
impl ReedSolomonException {
pub fn new(message: &str) -> Self {
Self {
message: message.to_owned(),
}
}
}
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>This class contains utility methods for performing mathematical operations over
* the Galois Fields. Operations use a given primitive polynomial in calculations.</p>
*
* <p>Throughout this package, elements of the GF are represented as an {@code int}
* for convenience and speed (but at the cost of memory).
* </p>
*
* @author Sean Owen
* @author David Olivier
*/
public final class GenericGF {
public static final GenericGF AZTEC_DATA_12 = new GenericGF(0x1069, 4096, 1); // x^12 + x^6 + x^5 + x^3 + 1
public static final GenericGF AZTEC_DATA_10 = new GenericGF(0x409, 1024, 1); // x^10 + x^3 + 1
public static final GenericGF AZTEC_DATA_6 = new GenericGF(0x43, 64, 1); // x^6 + x + 1
public static final GenericGF AZTEC_PARAM = new GenericGF(0x13, 16, 1); // x^4 + x + 1
public static final GenericGF QR_CODE_FIELD_256 = new GenericGF(0x011D, 256, 0); // x^8 + x^4 + x^3 + x^2 + 1
public static final GenericGF DATA_MATRIX_FIELD_256 = new GenericGF(0x012D, 256, 1); // x^8 + x^5 + x^3 + x^2 + 1
public static final GenericGF AZTEC_DATA_8 = DATA_MATRIX_FIELD_256;
public static final GenericGF MAXICODE_FIELD_64 = AZTEC_DATA_6;
private final int[] expTable;
private final int[] logTable;
private final GenericGFPoly zero;
private final GenericGFPoly one;
private final int size;
private final int primitive;
private final int generatorBase;
/**
* Create a representation of GF(size) using the given primitive polynomial.
*
* @param primitive irreducible polynomial whose coefficients are represented by
* the bits of an int, where the least-significant bit represents the constant
* coefficient
* @param size the size of the field
* @param b the factor b in the generator polynomial can be 0- or 1-based
* (g(x) = (x+a^b)(x+a^(b+1))...(x+a^(b+2t-1))).
* In most cases it should be 1, but for QR code it is 0.
*/
public GenericGF(int primitive, int size, int b) {
this.primitive = primitive;
this.size = size;
this.generatorBase = b;
expTable = new int[size];
logTable = new int[size];
int x = 1;
for (int i = 0; i < size; i++) {
expTable[i] = x;
x *= 2; // we're assuming the generator alpha is 2
if (x >= size) {
x ^= primitive;
x &= size - 1;
}
}
for (int i = 0; i < size - 1; i++) {
logTable[expTable[i]] = i;
}
// logTable[0] == 0 but this should never be used
zero = new GenericGFPoly(this, new int[]{0});
one = new GenericGFPoly(this, new int[]{1});
}
GenericGFPoly getZero() {
return zero;
}
GenericGFPoly getOne() {
return one;
}
/**
* @return the monomial representing coefficient * x^degree
*/
GenericGFPoly buildMonomial(int degree, int coefficient) {
if (degree < 0) {
throw new IllegalArgumentException();
}
if (coefficient == 0) {
return zero;
}
int[] coefficients = new int[degree + 1];
coefficients[0] = coefficient;
return new GenericGFPoly(this, coefficients);
}
/**
* Implements both addition and subtraction -- they are the same in GF(size).
*
* @return sum/difference of a and b
*/
static int addOrSubtract(int a, int b) {
return a ^ b;
}
/**
* @return 2 to the power of a in GF(size)
*/
int exp(int a) {
return expTable[a];
}
/**
* @return base 2 log of a in GF(size)
*/
int log(int a) {
if (a == 0) {
throw new IllegalArgumentException();
}
return logTable[a];
}
/**
* @return multiplicative inverse of a
*/
int inverse(int a) {
if (a == 0) {
throw new ArithmeticException();
}
return expTable[size - logTable[a] - 1];
}
/**
* @return product of a and b in GF(size)
*/
int multiply(int a, int b) {
if (a == 0 || b == 0) {
return 0;
}
return expTable[(logTable[a] + logTable[b]) % (size - 1)];
}
public int getSize() {
return size;
}
public int getGeneratorBase() {
return generatorBase;
}
@Override
public String toString() {
return "GF(0x" + Integer.toHexString(primitive) + ',' + size + ')';
}
}
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>Represents a polynomial whose coefficients are elements of a GF.
* Instances of this class are immutable.</p>
*
* <p>Much credit is due to William Rucklidge since portions of this code are an indirect
* port of his C++ Reed-Solomon implementation.</p>
*
* @author Sean Owen
*/
final class GenericGFPoly {
private final GenericGF field;
private final int[] coefficients;
/**
* @param field the {@link GenericGF} instance representing the field to use
* to perform computations
* @param coefficients coefficients as ints representing elements of GF(size), arranged
* from most significant (highest-power term) coefficient to least significant
* @throws IllegalArgumentException if argument is null or empty,
* or if leading coefficient is 0 and this is not a
* constant polynomial (that is, it is not the monomial "0")
*/
GenericGFPoly(GenericGF field, int[] coefficients) {
if (coefficients.length == 0) {
throw new IllegalArgumentException();
}
this.field = field;
int coefficientsLength = coefficients.length;
if (coefficientsLength > 1 && coefficients[0] == 0) {
// Leading term must be non-zero for anything except the constant polynomial "0"
int firstNonZero = 1;
while (firstNonZero < coefficientsLength && coefficients[firstNonZero] == 0) {
firstNonZero++;
}
if (firstNonZero == coefficientsLength) {
this.coefficients = new int[]{0};
} else {
this.coefficients = new int[coefficientsLength - firstNonZero];
System.arraycopy(coefficients,
firstNonZero,
this.coefficients,
0,
this.coefficients.length);
}
} else {
this.coefficients = coefficients;
}
}
int[] getCoefficients() {
return coefficients;
}
/**
* @return degree of this polynomial
*/
int getDegree() {
return coefficients.length - 1;
}
/**
* @return true iff this polynomial is the monomial "0"
*/
boolean isZero() {
return coefficients[0] == 0;
}
/**
* @return coefficient of x^degree term in this polynomial
*/
int getCoefficient(int degree) {
return coefficients[coefficients.length - 1 - degree];
}
/**
* @return evaluation of this polynomial at a given point
*/
int evaluateAt(int a) {
if (a == 0) {
// Just return the x^0 coefficient
return getCoefficient(0);
}
if (a == 1) {
// Just the sum of the coefficients
int result = 0;
for (int coefficient : coefficients) {
result = GenericGF.addOrSubtract(result, coefficient);
}
return result;
}
int result = coefficients[0];
int size = coefficients.length;
for (int i = 1; i < size; i++) {
result = GenericGF.addOrSubtract(field.multiply(a, result), coefficients[i]);
}
return result;
}
GenericGFPoly addOrSubtract(GenericGFPoly other) {
if (!field.equals(other.field)) {
throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
}
if (isZero()) {
return other;
}
if (other.isZero()) {
return this;
}
int[] smallerCoefficients = this.coefficients;
int[] largerCoefficients = other.coefficients;
if (smallerCoefficients.length > largerCoefficients.length) {
int[] temp = smallerCoefficients;
smallerCoefficients = largerCoefficients;
largerCoefficients = temp;
}
int[] sumDiff = new int[largerCoefficients.length];
int lengthDiff = largerCoefficients.length - smallerCoefficients.length;
// Copy high-order terms only found in higher-degree polynomial's coefficients
System.arraycopy(largerCoefficients, 0, sumDiff, 0, lengthDiff);
for (int i = lengthDiff; i < largerCoefficients.length; i++) {
sumDiff[i] = GenericGF.addOrSubtract(smallerCoefficients[i - lengthDiff], largerCoefficients[i]);
}
return new GenericGFPoly(field, sumDiff);
}
GenericGFPoly multiply(GenericGFPoly other) {
if (!field.equals(other.field)) {
throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
}
if (isZero() || other.isZero()) {
return field.getZero();
}
int[] aCoefficients = this.coefficients;
int aLength = aCoefficients.length;
int[] bCoefficients = other.coefficients;
int bLength = bCoefficients.length;
int[] product = new int[aLength + bLength - 1];
for (int i = 0; i < aLength; i++) {
int aCoeff = aCoefficients[i];
for (int j = 0; j < bLength; j++) {
product[i + j] = GenericGF.addOrSubtract(product[i + j],
field.multiply(aCoeff, bCoefficients[j]));
}
}
return new GenericGFPoly(field, product);
}
GenericGFPoly multiply(int scalar) {
if (scalar == 0) {
return field.getZero();
}
if (scalar == 1) {
return this;
}
int size = coefficients.length;
int[] product = new int[size];
for (int i = 0; i < size; i++) {
product[i] = field.multiply(coefficients[i], scalar);
}
return new GenericGFPoly(field, product);
}
GenericGFPoly multiplyByMonomial(int degree, int coefficient) {
if (degree < 0) {
throw new IllegalArgumentException();
}
if (coefficient == 0) {
return field.getZero();
}
int size = coefficients.length;
int[] product = new int[size + degree];
for (int i = 0; i < size; i++) {
product[i] = field.multiply(coefficients[i], coefficient);
}
return new GenericGFPoly(field, product);
}
GenericGFPoly[] divide(GenericGFPoly other) {
if (!field.equals(other.field)) {
throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
}
if (other.isZero()) {
throw new IllegalArgumentException("Divide by 0");
}
GenericGFPoly quotient = field.getZero();
GenericGFPoly remainder = this;
int denominatorLeadingTerm = other.getCoefficient(other.getDegree());
int inverseDenominatorLeadingTerm = field.inverse(denominatorLeadingTerm);
while (remainder.getDegree() >= other.getDegree() && !remainder.isZero()) {
int degreeDifference = remainder.getDegree() - other.getDegree();
int scale = field.multiply(remainder.getCoefficient(remainder.getDegree()), inverseDenominatorLeadingTerm);
GenericGFPoly term = other.multiplyByMonomial(degreeDifference, scale);
GenericGFPoly iterationQuotient = field.buildMonomial(degreeDifference, scale);
quotient = quotient.addOrSubtract(iterationQuotient);
remainder = remainder.addOrSubtract(term);
}
return new GenericGFPoly[] { quotient, remainder };
}
@Override
public String toString() {
if (isZero()) {
return "0";
}
StringBuilder result = new StringBuilder(8 * getDegree());
for (int degree = getDegree(); degree >= 0; degree--) {
int coefficient = getCoefficient(degree);
if (coefficient != 0) {
if (coefficient < 0) {
if (degree == getDegree()) {
result.append("-");
} else {
result.append(" - ");
}
coefficient = -coefficient;
} else {
if (result.length() > 0) {
result.append(" + ");
}
}
if (degree == 0 || coefficient != 1) {
int alphaPower = field.log(coefficient);
if (alphaPower == 0) {
result.append('1');
} else if (alphaPower == 1) {
result.append('a');
} else {
result.append("a^");
result.append(alphaPower);
}
}
if (degree != 0) {
if (degree == 1) {
result.append('x');
} else {
result.append("x^");
result.append(degree);
}
}
}
}
return result.toString();
}
}
/*
* Copyright 2007 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.reedsolomon;
/**
* <p>Implements Reed-Solomon decoding, as the name implies.</p>
*
* <p>The algorithm will not be explained here, but the following references were helpful
* in creating this implementation:</p>
*
* <ul>
* <li>Bruce Maggs.
* <a href="http://www.cs.cmu.edu/afs/cs.cmu.edu/project/pscico-guyb/realworld/www/rs_decode.ps">
* "Decoding Reed-Solomon Codes"</a> (see discussion of Forney's Formula)</li>
* <li>J.I. Hall. <a href="www.mth.msu.edu/~jhall/classes/codenotes/GRS.pdf">
* "Chapter 5. Generalized Reed-Solomon Codes"</a>
* (see discussion of Euclidean algorithm)</li>
* </ul>
*
* <p>Much credit is due to William Rucklidge since portions of this code are an indirect
* port of his C++ Reed-Solomon implementation.</p>
*
* @author Sean Owen
* @author William Rucklidge
* @author sanfordsquires
*/
public final class ReedSolomonDecoder {
private final GenericGF field;
public ReedSolomonDecoder(GenericGF field) {
this.field = field;
}
/**
* <p>Decodes given set of received codewords, which include both data and error-correction
* codewords. Really, this means it uses Reed-Solomon to detect and correct errors, in-place,
* in the input.</p>
*
* @param received data and error-correction codewords
* @param twoS number of error-correction codewords available
* @throws ReedSolomonException if decoding fails for any reason
*/
public void decode(int[] received, int twoS) throws ReedSolomonException {
GenericGFPoly poly = new GenericGFPoly(field, received);
int[] syndromeCoefficients = new int[twoS];
boolean noError = true;
for (int i = 0; i < twoS; i++) {
int eval = poly.evaluateAt(field.exp(i + field.getGeneratorBase()));
syndromeCoefficients[syndromeCoefficients.length - 1 - i] = eval;
if (eval != 0) {
noError = false;
}
}
if (noError) {
return;
}
GenericGFPoly syndrome = new GenericGFPoly(field, syndromeCoefficients);
GenericGFPoly[] sigmaOmega =
runEuclideanAlgorithm(field.buildMonomial(twoS, 1), syndrome, twoS);
GenericGFPoly sigma = sigmaOmega[0];
GenericGFPoly omega = sigmaOmega[1];
int[] errorLocations = findErrorLocations(sigma);
int[] errorMagnitudes = findErrorMagnitudes(omega, errorLocations);
for (int i = 0; i < errorLocations.length; i++) {
int position = received.length - 1 - field.log(errorLocations[i]);
if (position < 0) {
throw new ReedSolomonException("Bad error location");
}
received[position] = GenericGF.addOrSubtract(received[position], errorMagnitudes[i]);
}
}
private GenericGFPoly[] runEuclideanAlgorithm(GenericGFPoly a, GenericGFPoly b, int R)
throws ReedSolomonException {
// Assume a's degree is >= b's
if (a.getDegree() < b.getDegree()) {
GenericGFPoly temp = a;
a = b;
b = temp;
}
GenericGFPoly rLast = a;
GenericGFPoly r = b;
GenericGFPoly tLast = field.getZero();
GenericGFPoly t = field.getOne();
// Run Euclidean algorithm until r's degree is less than R/2
while (2 * r.getDegree() >= R) {
GenericGFPoly rLastLast = rLast;
GenericGFPoly tLastLast = tLast;
rLast = r;
tLast = t;
// Divide rLastLast by rLast, with quotient in q and remainder in r
if (rLast.isZero()) {
// Oops, Euclidean algorithm already terminated?
throw new ReedSolomonException("r_{i-1} was zero");
}
r = rLastLast;
GenericGFPoly q = field.getZero();
int denominatorLeadingTerm = rLast.getCoefficient(rLast.getDegree());
int dltInverse = field.inverse(denominatorLeadingTerm);
while (r.getDegree() >= rLast.getDegree() && !r.isZero()) {
int degreeDiff = r.getDegree() - rLast.getDegree();
int scale = field.multiply(r.getCoefficient(r.getDegree()), dltInverse);
q = q.addOrSubtract(field.buildMonomial(degreeDiff, scale));
r = r.addOrSubtract(rLast.multiplyByMonomial(degreeDiff, scale));
}
t = q.multiply(tLast).addOrSubtract(tLastLast);
if (r.getDegree() >= rLast.getDegree()) {
throw new IllegalStateException("Division algorithm failed to reduce polynomial? " +
"r: " + r + ", rLast: " + rLast);
}
}
int sigmaTildeAtZero = t.getCoefficient(0);
if (sigmaTildeAtZero == 0) {
throw new ReedSolomonException("sigmaTilde(0) was zero");
}
int inverse = field.inverse(sigmaTildeAtZero);
GenericGFPoly sigma = t.multiply(inverse);
GenericGFPoly omega = r.multiply(inverse);
return new GenericGFPoly[]{sigma, omega};
}
private int[] findErrorLocations(GenericGFPoly errorLocator) throws ReedSolomonException {
// This is a direct application of Chien's search
int numErrors = errorLocator.getDegree();
if (numErrors == 1) { // shortcut
return new int[] { errorLocator.getCoefficient(1) };
}
int[] result = new int[numErrors];
int e = 0;
for (int i = 1; i < field.getSize() && e < numErrors; i++) {
if (errorLocator.evaluateAt(i) == 0) {
result[e] = field.inverse(i);
e++;
}
}
if (e != numErrors) {
throw new ReedSolomonException("Error locator degree does not match number of roots");
}
return result;
}
private int[] findErrorMagnitudes(GenericGFPoly errorEvaluator, int[] errorLocations) {
// This is directly applying Forney's Formula
int s = errorLocations.length;
int[] result = new int[s];
for (int i = 0; i < s; i++) {
int xiInverse = field.inverse(errorLocations[i]);
int denominator = 1;
for (int j = 0; j < s; j++) {
if (i != j) {
//denominator = field.multiply(denominator,
// GenericGF.addOrSubtract(1, field.multiply(errorLocations[j], xiInverse)));
// Above should work but fails on some Apple and Linux JDKs due to a Hotspot bug.
// Below is a funny-looking workaround from Steven Parkes
int term = field.multiply(errorLocations[j], xiInverse);
int termPlus1 = (term & 0x1) == 0 ? term | 1 : term & ~1;
denominator = field.multiply(denominator, termPlus1);
}
}
result[i] = field.multiply(errorEvaluator.evaluateAt(xiInverse),
field.inverse(denominator));
if (field.getGeneratorBase() != 0) {
result[i] = field.multiply(result[i], xiInverse);
}
}
return result;
}
}
/*
* Copyright 2008 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.reedsolomon;
import java.util.ArrayList;
import java.util.List;
/**
* <p>Implements Reed-Solomon encoding, as the name implies.</p>
*
* @author Sean Owen
* @author William Rucklidge
*/
public final class ReedSolomonEncoder {
private final GenericGF field;
private final List<GenericGFPoly> cachedGenerators;
public ReedSolomonEncoder(GenericGF field) {
this.field = field;
this.cachedGenerators = new ArrayList<>();
cachedGenerators.add(new GenericGFPoly(field, new int[]{1}));
}
private GenericGFPoly buildGenerator(int degree) {
if (degree >= cachedGenerators.size()) {
GenericGFPoly lastGenerator = cachedGenerators.get(cachedGenerators.size() - 1);
for (int d = cachedGenerators.size(); d <= degree; d++) {
GenericGFPoly nextGenerator = lastGenerator.multiply(
new GenericGFPoly(field, new int[] { 1, field.exp(d - 1 + field.getGeneratorBase()) }));
cachedGenerators.add(nextGenerator);
lastGenerator = nextGenerator;
}
}
return cachedGenerators.get(degree);
}
public void encode(int[] toEncode, int ecBytes) {
if (ecBytes == 0) {
throw new IllegalArgumentException("No error correction bytes");
}
int dataBytes = toEncode.length - ecBytes;
if (dataBytes <= 0) {
throw new IllegalArgumentException("No data bytes provided");
}
GenericGFPoly generator = buildGenerator(ecBytes);
int[] infoCoefficients = new int[dataBytes];
System.arraycopy(toEncode, 0, infoCoefficients, 0, dataBytes);
GenericGFPoly info = new GenericGFPoly(field, infoCoefficients);
info = info.multiplyByMonomial(ecBytes, 1);
GenericGFPoly remainder = info.divide(generator)[1];
int[] coefficients = remainder.getCoefficients();
int numZeroCoefficients = ecBytes - coefficients.length;
for (int i = 0; i < numZeroCoefficients; i++) {
toEncode[dataBytes + i] = 0;
}
System.arraycopy(coefficients, 0, toEncode, dataBytes + numZeroCoefficients, coefficients.length);
}
}

View File

@@ -1 +1,143 @@
mod common;
mod common;
/*
* Copyright 2007 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;
/**
* Thrown when a barcode was not found in the image. It might have been
* partially detected but could not be confirmed.
*
* @author Sean Owen
*/
pub struct NotFoundException;
/*
* Copyright 2007 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;
/**
* Thrown when a barcode was successfully detected, but some aspect of
* the content did not conform to the barcode's format rules. This could have
* been due to a mis-detection.
*
* @author Sean Owen
*/
pub struct FormatException;
/*
* Copyright 2007 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;
/**
* Thrown when a barcode was successfully detected and decoded, but
* was not returned because its checksum feature failed.
*
* @author Sean Owen
*/
pub struct ChecksumException;
/*
* Copyright 2007 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;
/**
* The general exception class throw when something goes wrong during decoding of a barcode.
* This includes, but is not limited to, failing checksums / error correction algorithms, being
* unable to locate finder timing patterns, and so on.
*
* @author Sean Owen
*/
pub struct ReaderException;
/*
* Copyright 2008 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;
/**
* A base class which covers the range of exceptions which may occur when encoding a barcode using
* the Writer framework.
*
* @author dswitkin@google.com (Daniel Switkin)
*/
pub struct WriterException {
message: String,
}
impl WriterException {
pub fn new(message: &str) -> Self {
Self {
message: message.to_owned(),
}
}
}