/*
- * Copyright 2007 Google Inc.
+ * 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.
package com.google.zxing.common;
-import com.google.zxing.MonochromeBitmapSource;
-import com.google.zxing.ReaderException;
+import com.google.zxing.NotFoundException;
/**
* Implementations of this class can, given locations of finder patterns for a QR code in an
* The implementation used can be controlled by calling {@link #setGridSampler(GridSampler)}
* with an instance of a class which implements this interface.
*
- * @author srowen@google.com (Sean Owen)
+ * @author Sean Owen
*/
public abstract class GridSampler {
- private static GridSampler gridSampler;
+ private static GridSampler gridSampler = new DefaultGridSampler();
/**
* Sets the implementation of {@link GridSampler} used by the library. One global
* in the whole lifetime of the JVM. For instance, an Android activity can swap in
* an implementation that takes advantage of native platform libraries.
*
- * @param newGridSampler
+ * @param newGridSampler The platform-specific object to install.
*/
public static void setGridSampler(GridSampler newGridSampler) {
if (newGridSampler == null) {
* @return the current implementation of {@link GridSampler}
*/
public static GridSampler getInstance() {
- if (gridSampler == null) {
- gridSampler = new DefaultGridSampler();
- }
return gridSampler;
}
/**
- * <p>Samples an image for a square matrix of bits of the given dimension. This is used to extract the
- * black/white modules of a 2D barcode like a QR Code found in an image. Because this barcode may be
- * rotated or perspective-distorted, the caller supplies four points in the source image that define
- * known points in the barcode, so that the image may be sampled appropriately.</p>
- *
- * <p>The last eight "from" parameters are four X/Y coordinate pairs of locations of points in
- * the image that define some significant points in the image to be sample. For example,
- * these may be the location of finder pattern in a QR Code.</p>
- *
- * <p>The first eight "to" parameters are four X/Y coordinate pairs measured in the destination
- * {@link BitMatrix}, from the top left, where the known points in the image given by the "from" parameters
- * map to.</p>
- *
- * <p>These 16 parameters define the transformation needed to sample the image.</p>
- *
+ * Samples an image for a rectangular matrix of bits of the given dimension.
* @param image image to sample
- * @param dimension width/height of {@link BitMatrix} to sample from iamge
+ * @param dimensionX width of {@link BitMatrix} to sample from image
+ * @param dimensionY height of {@link BitMatrix} to sample from image
* @return {@link BitMatrix} representing a grid of points sampled from the image within a region
- * defined by the "from" parameters
- * @throws ReaderException if image can't be sampled, for example, if the transformation defined by
- * the given points is invalid or results in sampling outside the image boundaries
+ * defined by the "from" parameters
+ * @throws NotFoundException if image can't be sampled, for example, if the transformation defined
+ * by the given points is invalid or results in sampling outside the image boundaries
*/
- public abstract BitMatrix sampleGrid(MonochromeBitmapSource image,
- int dimension,
+ public abstract BitMatrix sampleGrid(BitMatrix image,
+ int dimensionX,
+ int dimensionY,
float p1ToX, float p1ToY,
float p2ToX, float p2ToY,
float p3ToX, float p3ToY,
float p1FromX, float p1FromY,
float p2FromX, float p2FromY,
float p3FromX, float p3FromY,
- float p4FromX, float p4FromY) throws ReaderException;
+ float p4FromX, float p4FromY) throws NotFoundException;
+
+ public abstract BitMatrix sampleGrid(BitMatrix image,
+ int dimensionX,
+ int dimensionY,
+ PerspectiveTransform transform) throws NotFoundException;
/**
* <p>Checks a set of points that have been transformed to sample points on an image against
* the image's dimensions to see if the point are even within the image.</p>
*
- * <p>This method will actually "nudge" the endpoints back onto the image if they are found to be barely
- * (less than 1 pixel) off the image. This accounts for imperfect detection of finder patterns in an image
- * where the QR Code runs all the way to the image border.</p>
+ * <p>This method will actually "nudge" the endpoints back onto the image if they are found to be
+ * barely (less than 1 pixel) off the image. This accounts for imperfect detection of finder
+ * patterns in an image where the QR Code runs all the way to the image border.</p>
*
* <p>For efficiency, the method will check points from either end of the line until one is found
* to be within the image. Because the set of points are assumed to be linear, this is valid.</p>
*
* @param image image into which the points should map
* @param points actual points in x1,y1,...,xn,yn form
- * @throws ReaderException if an endpoint is lies outside the image boundaries
+ * @throws NotFoundException if an endpoint is lies outside the image boundaries
*/
- protected static void checkAndNudgePoints(MonochromeBitmapSource image, float[] points) throws ReaderException {
+ protected static void checkAndNudgePoints(BitMatrix image, float[] points) throws NotFoundException {
int width = image.getWidth();
int height = image.getHeight();
// Check and nudge points from start until we see some that are OK:
int x = (int) points[offset];
int y = (int) points[offset + 1];
if (x < -1 || x > width || y < -1 || y > height) {
- throw new ReaderException("Transformed point out of bounds at " + x + ',' + y);
+ throw NotFoundException.getNotFoundInstance();
}
nudged = false;
if (x == -1) {
int x = (int) points[offset];
int y = (int) points[offset + 1];
if (x < -1 || x > width || y < -1 || y > height) {
- throw new ReaderException("Transformed point out of bounds at " + x + ',' + y);
+ throw NotFoundException.getNotFoundInstance();
}
nudged = false;
if (x == -1) {
projects / zxing.git / blobdiff