Moved CroppedMonochromeBitmapSource into the common package and fixed some more 100...

[zxing.git] / core / src / com / google / zxing / common / CroppedMonochromeBitmapSource.java

diff --git a/core/src/com/google/zxing/common/CroppedMonochromeBitmapSource.java b/core/src/com/google/zxing/common/CroppedMonochromeBitmapSource.java
new file mode 100644 (file)
index 0000000..c7d625d
--- /dev/null
+++ b/core/src/com/google/zxing/common/CroppedMonochromeBitmapSource.java
@@ -0,0 +1,98 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import com.google.zxing.BlackPointEstimationMethod;
+import com.google.zxing.MonochromeBitmapSource;
+import com.google.zxing.ReaderException;
+
+/**
+ * Encapulates a cropped region of another {@link com.google.zxing.MonochromeBitmapSource}.
+ *
+ * @author Sean Owen
+ */
+public final class CroppedMonochromeBitmapSource implements MonochromeBitmapSource {
+
+  private final MonochromeBitmapSource delegate;
+  private final int left;
+  private final int top;
+  private final int right;
+  private final int bottom;
+
+  /**
+   * Creates an instance that uses only a region of the given image as a source of pixels to decode.
+   *
+   * @param delegate image to decode a region of
+   * @param left x coordinate of leftmost pixels to decode
+   * @param top y coordinate of topmost pixels to decode
+   * @param right one more than the x coordinate of rightmost pixels to decode, i.e. we will decode
+   *  pixels whose x coordinate is in [left,right)
+   * @param bottom likewise, one more than the y coordinate of the bottommost pixels to decode
+   */
+  public CroppedMonochromeBitmapSource(MonochromeBitmapSource delegate,
+                                       int left, int top, int right, int bottom) {
+    this.delegate = delegate;
+    this.left = left;
+    this.top = top;
+    this.right = right;
+    this.bottom = bottom;
+  }
+
+  public boolean isBlack(int x, int y) {
+    return delegate.isBlack(left + x, top + y);
+  }
+
+  public BitArray getBlackRow(int y, BitArray row, int startX, int getWidth) {
+    return delegate.getBlackRow(top + y, row, left + startX, getWidth);
+  }
+
+  public BitArray getBlackColumn(int x, BitArray column, int startY, int getHeight) {
+    return delegate.getBlackColumn(left + x, column, top + startY, getHeight);
+  }
+
+  public int getHeight() {
+    return bottom - top;
+  }
+
+  public int getWidth() {
+    return right - left;
+  }
+
+  public void estimateBlackPoint(BlackPointEstimationMethod method, int argument)
+      throws ReaderException {
+    // Hmm, the delegate will probably base this on the whole image though...
+    delegate.estimateBlackPoint(method, argument);
+  }
+
+  public BlackPointEstimationMethod getLastEstimationMethod() {
+    return delegate.getLastEstimationMethod();
+  }
+
+  public MonochromeBitmapSource rotateCounterClockwise() {
+    MonochromeBitmapSource rotated = delegate.rotateCounterClockwise();
+    return new CroppedMonochromeBitmapSource(rotated,
+                                             top,
+                                             delegate.getWidth() - right,
+                                             delegate.getHeight() - bottom,
+                                             left);
+  }
+
+  public boolean isRotateSupported() {
+    return delegate.isRotateSupported();
+  }
+
+}