public override byte[] Decode(Bytes.Buffer data, PdfDirectObject parameters, IDictionary <PdfName, PdfDirectObject> header)
{
// get decode parameters
PdfDictionary decodeParms = parameters as PdfDictionary;
var ccittFaxParams = new CCITTFaxParams(
K: decodeParms.GetInt(PdfName.K),
endOfLine: decodeParms.GetBool(PdfName.EndOfLine),
encodedByteAlign: decodeParms.GetBool(PdfName.EncodedByteAlign),
columns: decodeParms.GetInt(PdfName.Columns),
rows: decodeParms.GetInt(PdfName.Rows),
endOfBlock: decodeParms.GetBool(PdfName.EndOfBlock),
blackIs1: decodeParms.GetBool(PdfName.BlackIs1)
);
var decoder = new CCITTFaxDecoder(data, ccittFaxParams);
using (var output = new Bytes.Buffer())
{
var currentByte = 0;
while ((currentByte = decoder.ReadNextChar()) > -1)
{
output.Append(FiltersExtension.ToByte(currentByte));
}
return(output.GetBuffer());
}
}
//BEWARE: codeTable must be local to each method, because there is only
// one instance of each filter
public override byte[] Decode(Bytes.Buffer data, PdfDirectObject parameters, IDictionary <PdfName, PdfDirectObject> header)
{
PdfDictionary decodeParams = (PdfDictionary)parameters;
int earlyChange = decodeParams?.GetInt(PdfName.EarlyChange, 1) ?? 1;
if (earlyChange != 0 && earlyChange != 1)
{
earlyChange = 1;
}
var result = DoLZWDecode(data, earlyChange);
return(DecodePredictor(result, parameters, header));
}
