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org.apache.pdfbox.filter
public class: RunLengthDecodeFilter [javadoc | source]
java.lang.Object
   org.apache.pdfbox.filter.RunLengthDecodeFilter

All Implemented Interfaces:
    Filter

This is a filter for the RunLength Decoder. From the PDF Reference
The RunLengthDecode filter decodes data that has been encoded in a simple
byte-oriented format based on run length. The encoded data is a sequence of
runs, where each run consists of a length byte followed by 1 to 128 bytes of data. If
the length byte is in the range 0 to 127, the following length + 1 (1 to 128) bytes
are copied literally during decompression. If length is in the range 129 to 255, the
following single byte is to be copied 257 ? length (2 to 128) times during decompression.
A length value of 128 denotes EOD.

The compression achieved by run-length encoding depends on the input data. In
the best case (all zeros), a compression of approximately 64:1 is achieved for long
files. The worst case (the hexadecimal sequence 00 alternating with FF) results in
an expansion of 127:128.
Constructor:
 public RunLengthDecodeFilter() 
Method from org.apache.pdfbox.filter.RunLengthDecodeFilter Summary:
decode,   encode
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.pdfbox.filter.RunLengthDecodeFilter Detail:
 public  void decode(InputStream compressedData,
    OutputStream result,
    COSDictionary options,
    int filterIndex) throws IOException 
    {@inheritDoc}
 public  void encode(InputStream rawData,
    OutputStream result,
    COSDictionary options,
    int filterIndex) throws IOException 
    {@inheritDoc}