/**
* Converts a 2D array of luminance data to 1 bit. As above, assume this method is expensive and
* do not call it repeatedly. This method is intended for decoding 2D barcodes and may or may not
* apply sharpening. Therefore, a row from this matrix may not be identical to one fetched using
* getBlackRow(), so don't mix and match between them.
*
* @return The 2D array of bits for the image (true means black).
* @throws NotFoundException if image can't be binarized to make a matrix
*/
public BitMatrix getBlackMatrix() throws NotFoundException {
// The matrix is created on demand the first time it is requested, then cached. There are two
// reasons for this:
// 1. This work will never be done if the caller only installs 1D Reader objects, or if a
// 1D Reader finds a barcode before the 2D Readers run.
// 2. This work will only be done once even if the caller installs multiple 2D Readers.
if (matrix == null) {
matrix = binarizer.getBlackMatrix();
}
return matrix;
}
/** @return Whether this bitmap can be cropped. */
public boolean isCropSupported() {
return binarizer.getLuminanceSource().isCropSupported();
}
/**
* Converts one row of luminance data to 1 bit data. May actually do the conversion, or return
* cached data. Callers should assume this method is expensive and call it as seldom as possible.
* This method is intended for decoding 1D barcodes and may choose to apply sharpening.
*
* @param y The row to fetch, which must be in [0, bitmap height)
* @param row An optional preallocated array. If null or too small, it will be ignored. If used,
* the Binarizer will call BitArray.clear(). Always use the returned object.
* @return The array of bits for this row (true means black).
* @throws NotFoundException if row can't be binarized
*/
public BitArray getBlackRow(int y, BitArray row) throws NotFoundException {
return binarizer.getBlackRow(y, row);
}
/** @return The height of the bitmap. */
public int getHeight() {
return binarizer.getHeight();
}
/** @return The width of the bitmap. */
public int getWidth() {
return binarizer.getWidth();
}
/**
* Returns a new object with rotated image data by 45 degrees counterclockwise. Only callable if
* {@link #isRotateSupported()} is true.
*
* @return A rotated version of this object.
*/
public BinaryBitmap rotateCounterClockwise45() {
LuminanceSource newSource = binarizer.getLuminanceSource().rotateCounterClockwise45();
return new BinaryBitmap(binarizer.createBinarizer(newSource));
}
/**
* Returns a new object with cropped image data. Implementations may keep a reference to the
* original data rather than a copy. Only callable if isCropSupported() is true.
*
* @param left The left coordinate, which must be in [0,getWidth())
* @param top The top coordinate, which must be in [0,getHeight())
* @param width The width of the rectangle to crop.
* @param height The height of the rectangle to crop.
* @return A cropped version of this object.
*/
public BinaryBitmap crop(int left, int top, int width, int height) {
LuminanceSource newSource = binarizer.getLuminanceSource().crop(left, top, width, height);
return new BinaryBitmap(binarizer.createBinarizer(newSource));
}