com.google.zxing

Class BinaryBitmap


  • public final class BinaryBitmap
extends Object
    This class is the core bitmap class used by ZXing to represent 1 bit data. Reader objects accept a BinaryBitmap and attempt to decode it.

    • Constructor Detail

      • BinaryBitmap

        public BinaryBitmap(Binarizer binarizer)

    • Method Detail

      • getWidth

        public int getWidth()
        Returns:
        The width of the bitmap.

      • getHeight

        public int getHeight()
        Returns:
        The height of the bitmap.

      • getBlackRow

        public BitArray getBlackRow(int y,
                            BitArray row)
                     throws NotFoundException
        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.
        Parameters:
        y - The row to fetch, which must be in [0, bitmap height)
        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.
        Returns:
        The array of bits for this row (true means black).
        Throws:
        NotFoundException - if row can't be binarized

      • getBlackMatrix

        public BitMatrix getBlackMatrix()
                         throws NotFoundException
        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.
        Returns:
        The 2D array of bits for the image (true means black).
        Throws:
        NotFoundException - if image can't be binarized to make a matrix

      • isCropSupported

        public boolean isCropSupported()
        Returns:
        Whether this bitmap can be cropped.

      • crop

        public BinaryBitmap crop(int left,
                         int top,
                         int width,
                         int height)
        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.
        Parameters:
        left - The left coordinate, which must be in [0,getWidth())
        top - The top coordinate, which must be in [0,getHeight())
        width - The width of the rectangle to crop.
        height - The height of the rectangle to crop.
        Returns:
        A cropped version of this object.

      • isRotateSupported

        public boolean isRotateSupported()
        Returns:
        Whether this bitmap supports counter-clockwise rotation.

      • rotateCounterClockwise

        public BinaryBitmap rotateCounterClockwise()
        Returns a new object with rotated image data by 90 degrees counterclockwise. Only callable if isRotateSupported() is true.
        Returns:
        A rotated version of this object.

      • rotateCounterClockwise45

        public BinaryBitmap rotateCounterClockwise45()
        Returns a new object with rotated image data by 45 degrees counterclockwise. Only callable if isRotateSupported() is true.
        Returns:
        A rotated version of this object.

      • toString

        public String toString()