Class BinaryBitmap

java.lang.Object
com.google.zxing.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.
  • Field Details

  • Constructor Details

    • BinaryBitmap

      public BinaryBitmap(Binarizer binarizer)
  • Method Details

    • 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()
      Overrides:
      toString in class Object