| jj2000.j2k.quantization.quantizer.CBlkQuantDataSrcEnc
All known Subclasses: jj2000.j2k.roi.encoder.ROIScaler, jj2000.j2k.quantization.quantizer.Quantizer,
| CBlkQuantDataSrcEnc | | public interface CBlkQuantDataSrcEnc extends ForwWTDataProps(Code) | | This interface defines a source of quantized wavelet coefficients and
methods to transfer them in a code-block by code-block basis. In each call
to 'getNextCodeBlock()' or 'getNextInternCodeBlock()' a new code-block is
returned. The code-blocks are returned in no specific order.
This class is the source of data for the entropy coder. See the
'EntropyCoder' 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'.
Note that no more of one object may request data, otherwise one object
would get some of the data and another one another part, in no defined
manner.
See Also: ForwWTDataProps
See Also: CBlkWTDataSrc
See Also: Quantizer
See Also: EntropyCoder |
| getNextCodeBlock | | public CBlkWTData getNextCodeBlock(int c, CBlkWTData cblk)(Code) | | Returns the next code-block in the current tile for the specified
component, as a copy (see below). The order in which code-blocks are
returned is not specified. However each code-block is returned only
once and all code-blocks will be returned if the method is called 'N'
times, where 'N' is the number of code-blocks in the tile. After all
the code-blocks have been returned for the current tile calls to this
method will return 'null'.
When changing the current tile (through 'setTile()' or 'nextTile()')
this method will always return the first code-block, as if this method
was never called before for the new current tile.
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
'CBlkWTData' class.
The 'ulx' and 'uly' members of the returned 'CBlkWTData' 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:
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 'c', ornull if all code-blocks for the current tile have been returned.
See Also: CBlkWTData |
| getNextInternCodeBlock | | public CBlkWTData getNextInternCodeBlock(int c, CBlkWTData cblk)(Code) | | Returns the next code-block in the current tile for the specified
component. The order in which code-blocks are returned is not
specified. However each code-block is returned only once and all
code-blocks will be returned if the method is called 'N' times, where
'N' is the number of code-blocks in the tile. After all the code-blocks
have been returned for the current tile calls to this method will
return 'null'.
When changing the current tile (through 'setTile()' or 'nextTile()')
this method will always return the first code-block, as if this method
was never called before for the new current tile.
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 'CBlkWTData' class.
The 'ulx' and 'uly' members of the returned 'CBlkWTData' 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:
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: CBlkWTData |
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