1 /*

     2 * Copyright (c) 2003, 2004 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  TJ2kStreamReader class is to implement the

    15 *                MJ2kPacketHeaderReader interface for reading the

    16 *                packet header and packet body from the stream

    17 *                buffer provided by ICL framework.

    18 *

    19 */

    20 

    21 

    22 #ifndef __JP2KSTREAMREADER_H__

    23 #define __JP2KSTREAMREADER_H__

    24 

    25 //  INCLUDES

    26 #include <e32base.h>

    27 #include "JP2KMarker.h"

    28 

    29 // CONSTANTS

    30 

    31 // MACROS

    32 

    33 // DATA TYPES

    34 

    35 // FUNCTION PROTOTYPES

    36 

    37 // FORWARD DECLARATIONS

    38 

    39 // CLASS DECLARATION

    40 

    41 /**

    42 * TJ2kStreamReader class is to implement the

    43 * MJ2kPacketHeaderReader interface for reading the

    44 * packet header and packet body from the stream

    45 * buffer provided by ICL framework.

    46 *

    47 * JP2KCodec.dll

    48 * @since 2.6

    49 */

    50 class TJ2kStreamReader : public MJ2kPacketHeaderReader

    51     {

    52     public:  // Constructors and destructor

    53         

    54     public: // New functions

    55         

    56         /**

    57         * Update the codestream length read and offset of SOT marker

    58         * @since 2.6

    59         */

    60         void  UpdateMainHeader();

    61 

    62         /**

    63         * Update the codestream length read and length of data consumed

    64         * @since 2.6

    65         */

    66         void  UpdateTileHeader();

    67 

    68         /**

    69         * From MJ2kPacketHeaderReader

    70         * Try to consume the EPH marker if there is one

    71         * @since 2.6

    72         * @return TUint8: true if end of buffer.

    73         */

    74         TUint8 ReadEPHMarker();

    75 

    76         /**

    77         * From MJ2kPacketHeaderReader

    78         * Read a bit from the packet header stream

    79         * @since 2.6

    80         * @param aBit: get a bit from the packet header bitstream.

    81         * @return TUint8: true if end of buffer.

    82         */

    83         TUint8 ReadBit( TUint8& aBit );

    84 

    85         /**

    86         * From MJ2kPacketHeaderReader

    87         * Read some bits from the packet header stream

    88         * @since 2.6

    89         * @param aBit: get some bits from the packet header bitstream.

    90         * @param aBitLen: how many bits to read.

    91         * @return TUint8: true if end of buffer.

    92         */

    93         TUint8 ReadBits( TUint8& aBit, TUint8 aBitLen );

    94 

    95         /**

    96         * From MJ2kPacketHeaderReader

    97         * Read some bits from the packet header stream

    98         * @since 2.6

    99         * @param aBit: get some bits from the packet header bitstream.

   100         * @param aBitLen: how many bits to read.

   101         * @return TUint8: true if end of buffer.

   102         */

   103         TUint8 ReadBits( TUint32& aBit, TUint8 aBitLen );

   104 

   105         /**

   106         * From MJ2kPacketHeaderReader

   107         * Start reading from packet header stream

   108         * @since 2.6

   109         * @return TUint8: true if end of buffer.

   110         */

   111         TUint8 StartReadBit();

   112 

   113         /**

   114         * From MJ2kPacketHeaderReader

   115         * Align the stream to the next byte boundary if necessary

   116         * @since 2.6

   117         */

   118         void AlignReader();

   119 

   120         /**

   121         * Try to consume the SOP marker if there is one

   122         * @since 2.6

   123         * @return TUint8: true if end of buffer.

   124         */

   125         TUint8 ReadSOPMarker();

   126 

   127         /**

   128         * Try to consume the EPH marker after failure on previous try

   129         * @since 2.6

   130         * @return TUint8: true if end of buffer.

   131         */

   132         TUint8 TryReadEPHMarker();

   133 

   134         /**

   135         * Try to align to byte boundary after failure on previous try

   136         * @since 2.6

   137         * @return TUint8: true if end of buffer.

   138         */

   139         TUint8 TryReAlignReader();

   140 

   141     public: // Functions from base classes

   142        

   143     protected:  // New functions       

   144 

   145     protected:  // Functions from base classes

   146 

   147     private:

   148 

   149     public:     // Data

   150 

   151         // Iterator pointed to current position in the buffer

   152         const TUint8 *iPtr;            

   153 

   154         // Iterator pointed to the start of buffer

   155         TUint8 *iPtrStart;       

   156 

   157         // Iterator pointed to the end of buffer

   158         TUint8 *iPtrEnd;         

   159 

   160         // Iterator pointed to the start of marker

   161         TUint8 *iPtrStartMarker; 

   162 

   163         // Data consumed during decoding

   164         TUint32 iDataUsed;       

   165 

   166         // Length of codestream left to be read

   167         TUint32 iCSLength;       

   168 

   169         // Offset position of first SOT

   170         TUint32 iStartSOT;       

   171 

   172         // Offset position of next tile to be processed

   173         TUint32 iNewDataStart;   

   174 

   175         // Length of data to skip

   176         TUint32 iSkipLength;     

   177 

   178         // Current data in 8 bits

   179         TUint8 iData;           

   180 

   181         // Current bit position

   182         TUint8 iPos;            

   183 

   184         // Bit position of next byte

   185         TUint8 iNextPos;        

   186 

   187         // To indicate byte alignment is required

   188         TUint8 iAlign;          

   189 

   190         // To indicate EPH marker should be tried

   191         TUint8 iTryEPHMarker;   

   192     

   193     protected:  // Data

   194 

   195     private:    // Data

   196 

   197     public:     // Friend classes

   198     

   199     protected:  // Friend classes

   200        

   201     private:    // Friend classes

   202 

   203     };

   204 

   205 #endif // __JP2KSTREAMREADER_H__

   206