jj2000.j2k.entropy.decoder

Interface CodedCBlkDataSrcDec

All Superinterfaces:

InvWTData, MultiResImgData

All Known Implementing Classes:

BitstreamReaderAgent, FileBitstreamReaderAgent

public interface CodedCBlkDataSrcDec
extends InvWTData

This interface defines a source of entropy coded data and methods to transfer it in a code-block by code-block basis. In each call to 'geCodeBlock()' a specified coded code-block is returned.

This interface is the source of data for the entropy decoder. See the 'EntropyDecoder' class.

For each coded-code-block the entropy-coded data is returned along with its truncation point information in a 'DecLyrdCBlk' object.

See Also:

EntropyDecoder, DecLyrdCBlk, BitstreamReaderAgent

Method Summary

Modifier and Type	Method and Description
DecLyrdCBlk	getCodeBlock(int c, int m, int n, SubbandSyn sb, int fl, int nl, DecLyrdCBlk ccb) Returns the specified coded code-block, for the specified component, in the current tile.

Methods inherited from interface jj2000.j2k.wavelet.synthesis.InvWTData

getCbULX, getCbULY, getSynSubbandTree

Methods inherited from interface jj2000.j2k.wavelet.synthesis.MultiResImgData

getCompImgHeight, getCompImgWidth, getCompSubsX, getCompSubsY, getImgHeight, getImgULX, getImgULY, getImgWidth, getNomTileHeight, getNomTileWidth, getNumComps, getNumTiles, getNumTiles, getResULX, getResULY, getTile, getTileCompHeight, getTileCompWidth, getTileHeight, getTileIdx, getTilePartULX, getTilePartULY, getTileWidth, nextTile, setTile

Method Detail

getCodeBlock

DecLyrdCBlk getCodeBlock(int c,
                         int m,
                         int n,
                         SubbandSyn sb,
                         int fl,
                         int nl,
                         DecLyrdCBlk ccb)

Returns the specified coded code-block, for the specified component, in the current tile. The first layer to return is indicated by 'fl'. The number of layers that is returned depends on 'nl' and the amount of data available.

The argument 'fl' is to be used by subsequent calls to this method for the same code-block. In this way supplamental data can be retrieved at a later time. The fact that data from more than one layer can be returned means that several packets from the same code-block, of the same component, and the same tile, have been concatenated.

The returned compressed code-block can have its progressive attribute set. If this attribute is set it means that more data can be obtained by subsequent calls to this method (subject to transmission delays, etc). If the progressive attribute is not set it means that the returned data is all the data that can be obtained for the specified subblock.

The compressed code-block is uniquely specified by the current tile, the component (identified by 'c'), the subband (indentified by 'sb') and the code-bock vertical and horizontal indexes 'm' and 'n'.

The 'ulx' and 'uly' members of the returned 'DecLyrdCBlk' object contain the coordinates of the top-left corner of the block, with respect to the tile, not the subband.

Parameters:

c - The index of the component, from 0 to N-1.

m - The vertical index of the code-block to return, in the specified subband.

n - The horizontal index of the code-block to return, in the specified subband.

sb - The subband in whic the requested code-block is.

fl - The first layer to return.

nl - The number of layers to return, if negative all available layers are returned, starting at 'fl'.

ccb - If not null this object is used to return the compressed code-block. If null a new object is created and returned. If the data array in ccb is not null then it can be reused to return the compressed data.

Returns:

The compressed code-block, with a certain number of layers determined by the available data and 'nl'.