/// <summary> <p>Convenience method that can decode a PDF417 Code represented as a 2D array of booleans.
/// "true" is taken to mean a black module.</p>
///
/// </summary>
/// <param name="image">booleans representing white/black PDF417 modules
/// </param>
/// <returns> text and bytes encoded within the PDF417 Code
/// </returns>
/// <throws> ReaderException if the PDF417 Code cannot be decoded </throws>
public DecoderResult decode(bool[][] image)
{
int dimension = image.Length;
BitMatrix bits = new BitMatrix(dimension);
for (int i = 0; i < dimension; i++)
{
for (int j = 0; j < dimension; j++)
{
if (image[j][i])
{
bits.set_Renamed(j, i);
}
}
}
return decode(bits);
}
/// <summary> This method detects a barcode in a "pure" image -- that is, pure monochrome image
/// which contains only an unrotated, unskewed, image of a barcode, with some white border
/// around it. This is a specialized method that works exceptionally fast in this special
/// case.
/// </summary>
private static BitMatrix extractPureBits(BinaryBitmap image)
{
// Now need to determine module size in pixels
BitMatrix matrix = image.BlackMatrix;
int height = matrix.Height;
int width = matrix.Width;
int minDimension = System.Math.Min(height, width);
// First, skip white border by tracking diagonally from the top left down and to the right:
int borderWidth = 0;
while (borderWidth < minDimension && !matrix.get_Renamed(borderWidth, borderWidth))
{
borderWidth++;
}
if (borderWidth == minDimension)
{
throw ReaderException.Instance;
}
// And then keep tracking across the top-left black module to determine module size
int moduleEnd = borderWidth;
while (moduleEnd < minDimension && matrix.get_Renamed(moduleEnd, moduleEnd))
{
moduleEnd++;
}
if (moduleEnd == minDimension)
{
throw ReaderException.Instance;
}
int moduleSize = moduleEnd - borderWidth;
// And now find where the rightmost black module on the first row ends
int rowEndOfSymbol = width - 1;
while (rowEndOfSymbol >= 0 && !matrix.get_Renamed(rowEndOfSymbol, borderWidth))
{
rowEndOfSymbol--;
}
if (rowEndOfSymbol < 0)
{
throw ReaderException.Instance;
}
rowEndOfSymbol++;
// Make sure width of barcode is a multiple of module size
if ((rowEndOfSymbol - borderWidth) % moduleSize != 0)
{
throw ReaderException.Instance;
}
int dimension = (rowEndOfSymbol - borderWidth) / moduleSize;
// Push in the "border" by half the module width so that we start
// sampling in the middle of the module. Just in case the image is a
// little off, this will help recover.
borderWidth += (moduleSize >> 1);
int sampleDimension = borderWidth + (dimension - 1) * moduleSize;
if (sampleDimension >= width || sampleDimension >= height)
{
throw ReaderException.Instance;
}
// Now just read off the bits
BitMatrix bits = new BitMatrix(dimension);
for (int y = 0; y < dimension; y++)
{
int iOffset = borderWidth + y * moduleSize;
for (int x = 0; x < dimension; x++)
{
if (matrix.get_Renamed(borderWidth + x * moduleSize, iOffset))
{
bits.set_Renamed(x, y);
}
}
}
return bits;
}
/// <summary> This method detects a Data Matrix code in a "pure" image -- that is, pure monochrome image
/// which contains only an unrotated, unskewed, image of a Data Matrix code, with some white border
/// around it. This is a specialized method that works exceptionally fast in this special
/// case.
/// </summary>
private static BitMatrix extractPureBits(BitMatrix image)
{
// Now need to determine module size in pixels
int height = image.Height;
int width = image.Width;
int minDimension = System.Math.Min(height, width);
// First, skip white border by tracking diagonally from the top left down and to the right:
int borderWidth = 0;
while (borderWidth < minDimension && !image.get_Renamed(borderWidth, borderWidth))
{
borderWidth++;
}
if (borderWidth == minDimension)
{
throw ReaderException.Instance;
}
// And then keep tracking across the top-left black module to determine module size
int moduleEnd = borderWidth + 1;
while (moduleEnd < width && image.get_Renamed(moduleEnd, borderWidth))
{
moduleEnd++;
}
if (moduleEnd == width)
{
throw ReaderException.Instance;
}
int moduleSize = moduleEnd - borderWidth;
// And now find where the bottommost black module on the first column ends
int columnEndOfSymbol = height - 1;
while (columnEndOfSymbol >= 0 && !image.get_Renamed(borderWidth, columnEndOfSymbol))
{
columnEndOfSymbol--;
}
if (columnEndOfSymbol < 0)
{
throw ReaderException.Instance;
}
columnEndOfSymbol++;
// Make sure width of barcode is a multiple of module size
if ((columnEndOfSymbol - borderWidth) % moduleSize != 0)
{
throw ReaderException.Instance;
}
int dimension = (columnEndOfSymbol - borderWidth) / moduleSize;
// Push in the "border" by half the module width so that we start
// sampling in the middle of the module. Just in case the image is a
// little off, this will help recover.
borderWidth += (moduleSize >> 1);
int sampleDimension = borderWidth + (dimension - 1) * moduleSize;
if (sampleDimension >= width || sampleDimension >= height)
{
throw ReaderException.Instance;
}
// Now just read off the bits
BitMatrix bits = new BitMatrix(dimension);
for (int i = 0; i < dimension; i++)
{
int iOffset = borderWidth + i * moduleSize;
for (int j = 0; j < dimension; j++)
{
if (image.get_Renamed(borderWidth + j * moduleSize, iOffset))
{
bits.set_Renamed(j, i);
}
}
}
return bits;
}
