| jj2000.j2k.quantization.dequantizer.CBlkQuantDataSrcDec
All known Subclasses: jj2000.j2k.entropy.decoder.EntropyDecoder, jj2000.j2k.roi.ROIDeScaler,
| CBlkQuantDataSrcDec | | public interface CBlkQuantDataSrcDec extends InvWTData(Code) | | This interface defines a source of quantized wavelet coefficients and
methods to transfer them in a code-block by code-block basis, fro the
decoder side. In each call to 'getCodeBlock()' or 'getInternCodeBlock()' a
new code-block is returned.
This class is the source of data for the dequantizer. See the
'Dequantizer' class.
Code-block data is returned in sign-magnitude representation, instead of
the normal two's complement one. Only integral types are used. The sign
magnitude representation is more adequate for entropy coding. In sign
magnitude representation, the most significant bit is used for the sign (0
if positive, 1 if negative) and the magnitude of the coefficient is stored
in the next M most significant bits. The rest of the bits (least
significant bits) can contain a fractional value of the quantized
coefficient. The number 'M' of magnitude bits is communicated in the
'magbits' member variable of the 'CBlkWTData'.
See Also: InvWTData
See Also: CBlkWTDataSrcDec
See Also: Dequantizer
See Also: EntropyDecoder |
| Method Summary | |
| public DataBlk | getCodeBlock(int c, int m, int n, SubbandSyn sb, DataBlk cblk)
Returns the specified code-block in the current tile for the specified
component, as a copy (see below).
The returned code-block may be progressive, which is indicated by
the 'progressive' variable of the returned 'DataBlk' object. | | public DataBlk | getInternCodeBlock(int c, int m, int n, SubbandSyn sb, DataBlk cblk)
Returns the specified code-block in the current tile for the specified
component (as a reference or copy).
The returned code-block may be progressive, which is indicated by
the 'progressive' variable of the returned 'DataBlk' object. |
| getCodeBlock | | public DataBlk getCodeBlock(int c, int m, int n, SubbandSyn sb, DataBlk cblk)(Code) | | Returns the specified code-block in the current tile for the specified
component, as a copy (see below).
The returned code-block may be progressive, which is indicated by
the 'progressive' variable of the returned 'DataBlk' object. If a
code-block is progressive it means that in a later request to this
method for the same code-block it is possible to retrieve data which is
a better approximation, since meanwhile more data to decode for the
code-block could have been received. If the code-block is not
progressive then later calls to this method for the same code-block
will return the exact same data values.
The data returned by this method is always a copy of the internal
data of this object, if any, and it can be modified "in place" without
any problems after being returned. The 'offset' of the returned data is
0, and the 'scanw' is the same as the code-block width. See the
'DataBlk' class.
The 'ulx' and 'uly' members of the returned 'DataBlk' object contain
the coordinates of the top-left corner of the block, with respect to
the tile, not the subband.
Parameters:
c - The component for which to return the next code-block.
Parameters:
m - The vertical index of the code-block to return, in thespecified subband.
Parameters:
n - The horizontal index of the code-block to return, in thespecified subband.
Parameters:
sb - The subband in which the code-block to return is.
Parameters:
cblk - If non-null this object will be used to return the newcode-block. If null a new one will be allocated and returned. If the"data" array of the object is non-null it will be reused, if possible,to return the data. The next code-block in the current tile for component 'n', ornull if all code-blocks for the current tile have been returned.
See Also: DataBlk |
| getInternCodeBlock | | public DataBlk getInternCodeBlock(int c, int m, int n, SubbandSyn sb, DataBlk cblk)(Code) | | Returns the specified code-block in the current tile for the specified
component (as a reference or copy).
The returned code-block may be progressive, which is indicated by
the 'progressive' variable of the returned 'DataBlk' object. If a
code-block is progressive it means that in a later request to this
method for the same code-block it is possible to retrieve data which is
a better approximation, since meanwhile more data to decode for the
code-block could have been received. If the code-block is not
progressive then later calls to this method for the same code-block
will return the exact same data values.
The data returned by this method can be the data in the internal
buffer of this object, if any, and thus can not be modified by the
caller. The 'offset' and 'scanw' of the returned data can be
arbitrary. See the 'DataBlk' class.
The 'ulx' and 'uly' members of the returned 'DataBlk' object contain
the coordinates of the top-left corner of the block, with respect to
the tile, not the subband.
Parameters:
c - The component for which to return the next code-block.
Parameters:
m - The vertical index of the code-block to return, in thespecified subband.
Parameters:
n - The horizontal index of the code-block to return, in thespecified subband.
Parameters:
sb - The subband in which the code-block to return is.
Parameters:
cblk - If non-null this object will be used to return the newcode-block. If null a new one will be allocated and returned. If the"data" array of the object is non-null it will be reused, if possible,to return the data. The next code-block in the current tile for component 'n', ornull if all code-blocks for the current tile have been returned.
See Also: DataBlk |
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