Constructor Detail

• PktDecoder

  public PktDecoder(DecoderSpecs decSpec,
                    HeaderDecoder hd,
                    RandomAccessIO ehs,
                    BitstreamReaderAgent src,
                    boolean isTruncMode,
                    int maxCB)

  Creates an empty PktDecoder object associated with given decoder specifications and HeaderDecoder. This object must be initialized thanks to the restart method before being used.

  Parameters:

  decSpec - The decoder specifications.

  hd - The HeaderDecoder instance.

  ehs - The stream where to read data from.

  src - The bit stream reader agent.

  isTruncMode - Whether or not truncation mode is required.

  maxCB - The maximum number of code-blocks to read before ncbquit

Method Detail

• restart

  public CBlkInfo[][][][][] restart(int nc,
                                    int[] mdl,
                                    int nl,
                                    CBlkInfo[][][][][] cbI,
                                    boolean pph,
                                    ByteArrayInputStream pphbais)

  Re-initialize the PktDecoder instance at the beginning of a new tile.

  Parameters:

  nc - The number of components in this tile

  mdl - The maximum number of decomposition level in each component of this tile

  nl - The number of layers in this tile

  cbI - The code-blocks array

  pph - Flag indicating whether packed packet headers was used

  pphbais - Stream containing the packed packet headers

• getNumPrecinct

  public int getNumPrecinct(int c,
                            int r)

  Gets the number of precincts in a given component and resolution level.

  Parameters:

  c - Component index

  r - Resolution index

• readPktHead

  public boolean readPktHead(int l,
                             int r,
                             int c,
                             int p,
                             CBlkInfo[][][] cbI,
                             int[] nb)
                      throws IOException

  Read specified packet head and found length of each code-block's piece of codewords as well as number of skipped most significant bit-planes.

  Parameters:

  l - layer index

  r - Resolution level index

  c - Component index

  p - Precinct index

  cbI - CBlkInfo array of relevant component and resolution level.

  nb - The number of bytes to read in each tile before reaching output rate (used by truncation mode)

  Returns:

  True if specified output rate or EOF is reached.

  Throws:

  IOException

• readPktBody

  public boolean readPktBody(int l,
                             int r,
                             int c,
                             int p,
                             CBlkInfo[][][] cbI,
                             int[] nb)
                      throws IOException

  Reads specificied packet body in order to find offset of each code-block's piece of codeword. This use the list of found code-blocks in previous red packet head.

  Parameters:

  l - layer index

  r - Resolution level index

  c - Component index

  p - Precinct index

  cbI - CBlkInfo array of relevant component and resolution level.

  nb - The remainding number of bytes to read from the bit stream in each tile before reaching the decoding rate (in truncation mode)

  Returns:

  True if decoding rate is reached

  Throws:

  IOException

• getPPX

  public final int getPPX(int t,
                          int c,
                          int r)

  Returns the precinct partition width for the specified component, resolution level and tile.

  Parameters:

  t - the tile index

  c - The index of the component (between 0 and C-1)

  r - The resolution level, from 0 to L.

  Returns:

  the precinct partition width for the specified component, resolution level and tile.

• getPPY

  public final int getPPY(int t,
                          int c,
                          int rl)

  Returns the precinct partition height for the specified component, resolution level and tile.

  Parameters:

  t - the tile index

  c - The index of the component (between 0 and C-1)

  rl - The resolution level, from 0 to L.

  Returns:

  the precinct partition height in the specified component, for the specified resolution level, for the current tile.

• readSOPMarker

  public boolean readSOPMarker(int[] nBytes,
                               int p,
                               int c,
                               int r)
                        throws IOException

  Try to read a SOP marker and check that its sequence number if not out of sequence. If so, an error is thrown.

  Parameters:

  nBytes - The number of bytes left to read from each tile

  p - Precinct index

  r - Resolution level index

  c - Component index

  Throws:

  IOException

• readEPHMarker

  public void readEPHMarker(io.scif.jj2000.j2k.codestream.reader.PktHeaderBitReader bin)
                     throws IOException

  Try to read an EPH marker. If it is not possible then an Error is thrown.

  Parameters:

  bin - The packet header reader to read the EPH marker from

  Throws:

  IOException

• getPrecInfo

  public PrecInfo getPrecInfo(int c,
                              int r,
                              int p)

  Get PrecInfo instance of the specified resolution level, component and precinct.

  Parameters:

  c - Component index.

  r - Resolution level index.

  p - Precinct index.