/* * CVS identifier: * * $Id: CBlkQuantDataSrcDec.java,v 1.9 2001/09/14 08:58:36 grosbois Exp $ * * Class: CBlkQuantDataSrcDec * * Description: Interface that defines a source of * quantized wavelet data to be transferred in a * code-block by code-block basis (decoder side). * * * * COPYRIGHT: * * This software module was originally developed by Raphaël Grosbois and * Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel * Askelöf (Ericsson Radio Systems AB); and Bertrand Berthelot, David * Bouchard, Félix Henry, Gerard Mozelle and Patrice Onno (Canon Research * Centre France S.A) in the course of development of the JPEG2000 * standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This * software module is an implementation of a part of the JPEG 2000 * Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio * Systems AB and Canon Research Centre France S.A (collectively JJ2000 * Partners) agree not to assert against ISO/IEC and users of the JPEG * 2000 Standard (Users) any of their rights under the copyright, not * including other intellectual property rights, for this software module * with respect to the usage by ISO/IEC and Users of this software module * or modifications thereof for use in hardware or software products * claiming conformance to the JPEG 2000 Standard. Those intending to use * this software module in hardware or software products are advised that * their use may infringe existing patents. The original developers of * this software module, JJ2000 Partners and ISO/IEC assume no liability * for use of this software module or modifications thereof. No license * or right to this software module is granted for non JPEG 2000 Standard * conforming products. JJ2000 Partners have full right to use this * software module for his/her own purpose, assign or donate this * software module to any third party and to inhibit third parties from * using this software module for non JPEG 2000 Standard conforming * products. This copyright notice must be included in all copies or * derivative works of this software module. * * Copyright (c) 1999/2000 JJ2000 Partners. * */ using System; using CSJ2K.j2k.wavelet.synthesis; using CSJ2K.j2k.entropy.decoder; using CSJ2K.j2k.image; namespace CSJ2K.j2k.quantization.dequantizer { /// 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'. /// ///

/// /// /// /// /// /// /// /// /// public interface CBlkQuantDataSrcDec:InvWTData { /// 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.

/// ///
/// The component for which to return the next code-block. /// /// /// The vertical index of the code-block to return, in the /// specified subband. /// /// /// The horizontal index of the code-block to return, in the /// specified subband. /// /// /// The subband in which the code-block to return is. /// /// /// If non-null this object will be used to return the new /// code-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', or /// null if all code-blocks for the current tile have been returned. /// /// /// /// /// 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 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.

/// ///
/// The component for which to return the next code-block. /// /// /// The vertical index of the code-block to return, in the /// specified subband. /// /// /// The horizontal index of the code-block to return, in the /// specified subband. /// /// /// The subband in which the code-block to return is. /// /// /// If non-null this object will be used to return the new /// code-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', or /// null if all code-blocks for the current tile have been returned. /// /// /// /// /// DataBlk getInternCodeBlock(int c, int m, int n, SubbandSyn sb, DataBlk cblk); } }