Ts2BitUtils.h

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/*****************************************************************
|
|   MPEG2 Transport Stream - Bit Utils (adapted from Fluo and Bento4)
|
|   $Id: Ts2BitUtils.h 296 2014-06-25 11:20:09Z jebaseelir $
|   Original author:  Gilles Boccon-Gibod
|
|   This software is provided to you pursuant to your agreement 
|   with Intertrust Technologies Corporation ("Intertrust"). 
|   This software may be used only in accordance with the terms 
|   of the agreement.
|      
|   Copyright (c) 2005-2014 by Intertrust. All rights reserved. 
|
****************************************************************/

#ifndef _TS2_BIT_UTILS_H_
#define _TS2_BIT_UTILS_H_

/*----------------------------------------------------------------------
|       includes
+---------------------------------------------------------------------*/
#include "Atomix.h"

/*----------------------------------------------------------------------
|   types helpers
+---------------------------------------------------------------------*/
/* use long by default */
typedef ATX_UInt32     TS2_BitsWord;
#define TS2_WORD_BITS  32
#define TS2_WORD_BYTES 4

/*----------------------------------------------------------------------
|   types
+---------------------------------------------------------------------*/
typedef struct {
    const ATX_Byte* data;
    ATX_Size        data_size;
    ATX_UInt32      pos;
    TS2_BitsWord    cache;
    ATX_UInt8       bits_cached;
} TS2_BitStream;

typedef struct {
    ATX_Byte*       data;
    ATX_Size        data_size;
    ATX_UInt64      bit_count;
} TS2_BitWriter;

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/*----------------------------------------------------------------------
|   TS2_BitStream functions
+---------------------------------------------------------------------*/
ATX_Result   TS2_BitStream_SetData(TS2_BitStream*  bits, 
                                   const ATX_Byte* data, 
                                   ATX_Size        data_size);
    
ATX_Result   TS2_BitStream_Reset(TS2_BitStream* bits);
    
ATX_Size     TS2_BitStream_GetBitsLeft(TS2_BitStream* bits);
    
ATX_Result   TS2_BitStream_Rewind(TS2_BitStream* bits, ATX_UInt32 n);
    
ATX_UInt32   TS2_BitStream_ReadBits(TS2_BitStream* bits, ATX_UInt32 n);
    
ATX_UInt32   TS2_BitStream_ReadBit(TS2_BitStream* bits);
    
ATX_UInt64   TS2_BitStream_Read64(TS2_BitStream* bits, ATX_UInt32 n);
    
ATX_Result   TS2_BitStream_ReadTimecode(TS2_BitStream* bits, ATX_UInt64* timecode);
    
ATX_UInt32   TS2_BitStream_PeekBits(const TS2_BitStream* bits, ATX_UInt32 n);
    
ATX_UInt32   TS2_BitStream_PeekBit(const TS2_BitStream* bits);
    
void         TS2_BitStream_SkipBits(TS2_BitStream* bits, ATX_UInt32 n);
    
void         TS2_BitStream_SkipBit(TS2_BitStream* bits);

/*----------------------------------------------------------------------
|   TS2_BitWriter functions
+---------------------------------------------------------------------*/
ATX_Result TS2_BitWriter_SetData(TS2_BitWriter* writer,
                                 ATX_Byte*      data,
                                 ATX_Size       data_size);
    
ATX_Result TS2_BitWriter_Write(TS2_BitWriter* writer,
                               ATX_UInt32     bits,
                               ATX_UInt32     bit_count);
    
ATX_Result TS2_BitWriter_WriteAlignedBytes(TS2_BitWriter* writer,
                                           ATX_Byte*      data,
                                           ATX_Size       data_size);
    
#define TS2_BitWriter_IsByteAligned(writer) ((writer)->bit_count%8 == 0)
    
#define TS2_BitWriter_ByteCount(writer) ((ATX_UInt32)((writer)->bit_count / 8))

#ifdef __cplusplus
}
#endif /* __cplusplus */


#endif /* _TS2_BIT_UTILS_H_ */