celp_bitstream_demux.c

MPEG-4编解码的实现(包括MPEG4视音频编解码)

/*====================================================================*/
/*         MPEG-4 Audio (ISO/IEC 14496-3) Copyright Header            */
/*====================================================================*/
/*
This software module was originally developed by Rakesh Taori and Andy
Gerrits (Philips Research Laboratories, Eindhoven, The Netherlands) in
the course of development of the MPEG-4 Audio (ISO/IEC 14496-3). This
software module is an implementation of a part of one or more MPEG-4
Audio (ISO/IEC 14496-3) tools as specified by the MPEG-4 Audio
(ISO/IEC 14496-3). ISO/IEC gives users of the MPEG-4 Audio (ISO/IEC
14496-3) free license to this software module or modifications thereof
for use in hardware or software products claiming conformance to the
MPEG-4 Audio (ISO/IEC 14496-3). Those intending to use this software
module in hardware or software products are advised that its use may
infringe existing patents. The original developer of this software
module and his/her company, the subsequent editors and their
companies, and ISO/IEC have no liability for use of this software
module or modifications thereof in an implementation. Copyright is not
released for non MPEG-4 Audio (ISO/IEC 14496-3) conforming products.
CN1 retains full right to use the code for his/her own purpose, assign
or donate the code to a third party and to inhibit third parties from
using the code for non MPEG-4 Audio (ISO/IEC 14496-3) conforming
products.  This copyright notice must be included in all copies or
derivative works. Copyright 1996.
*/
/*====================================================================*/
/*====================================================================*/
/*                                                                    */
/*      SOURCE_FILE:    CELP_BITSTREAM_DEMUX.C                        */
/*      COMPONENT:      Bitstream to Parameter converter              */
/*                                                                    */
/*====================================================================*/
    
/*====================================================================*/
/*      I N C L U D E S                                               */
/*====================================================================*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

#include "buffersHandle.h"       /* handler, defines, enums */

#include "bitstream.h"
#include "phi_cons.h"      
#include "lpc_common.h"  /* Common LPC core Defined Constants           */
#include "celp_bitstream_demux.h"    /* Parameter to bitstream conversion routines  */
/* #include "phi_freq.h"   */
#include "pan_celp_const.h"

/*======================================================================*/
/*      G L O B A L    D A T A   D E F I N I T I O N S                  */
/*======================================================================*/
/*
static short freq[ORDER_LPC_16 + 1][36];
static int counter[ORDER_LPC_16 + 1];
static long frame_count = 1;
static long ft = 1;
*/
/*======================================================================*/
/* Function Definition: read_celp_bitstream_header                     */
/*======================================================================*/
void read_celp_bitstream_header(
    BsBitStream *hdrStream,           /* In: Bitstream                     */
    long * const ExcitationMode, 	 /* In: Excitation Mode 			*/
    long * const SampleRateMode, 	 /* In: SampleRate Mode 			*/
    long * const QuantizationMode,	 /* In: Type of Quantization		*/
    long * const FineRateControl,	 /* In: Fine Rate Control switch	*/
    long * const LosslessCodingMode,  /* In: Lossless Coding Mode		*/
    long * const RPE_configuration,	 /* In: Wideband configuration  	*/
    long * const Wideband_VQ,		 /* In: Wideband VQ mode			*/
    long * const MPE_Configuration,	 /* In: Narrowband configuration	*/
    long * const NumEnhLayers,		 /* In: Number of Enhancement Layers*/
    long * const BandwidthScalabilityMode, /* In: bandwidth switch		 */
    long * const BWS_Configuration	 /* In: BWS_configuration			*/
    )
{
    unsigned long temp;
    *QuantizationMode = VectorQuantizer;
    *Wideband_VQ = Optimized_VQ;
    /* -----------------------------------------------------------------*/
    /* Read Excitation mode                                          */
    /* -----------------------------------------------------------------*/
    
	BsGetBit(hdrStream, &temp, 1); *ExcitationMode = temp;
	
    /* -----------------------------------------------------------------*/
    /* Read Sampling Rate mode                                          */
    /* -----------------------------------------------------------------*/
    BsGetBit(hdrStream, &temp, 1); *SampleRateMode = temp;

    /* -----------------------------------------------------------------*/
    /* Read FineRateControl                                             */
    /* -----------------------------------------------------------------*/
    BsGetBit(hdrStream, &temp, 1); *FineRateControl = temp;

    /* -----------------------------------------------------------------*/
    /* Read Configuration                                               */
    /* -----------------------------------------------------------------*/
    if (*ExcitationMode == RegularPulseExc )
    {
        BsGetBit(hdrStream, &temp, 3); *RPE_configuration = temp;
    }

    if (*ExcitationMode == MultiPulseExc )
    {
	BsGetBit(hdrStream, &temp, 5); *MPE_Configuration = temp;
	BsGetBit(hdrStream, &temp, 2); *NumEnhLayers = temp;
	/* -------------------------------------------------------------*/
	/* Read Bandwidth Scalability Mode                              */
	/* -------------------------------------------------------------*/
	BsGetBit(hdrStream, &temp, 1); *BandwidthScalabilityMode = temp;
	if (*BandwidthScalabilityMode == ON)
	{
	    /* ---------------------------------------------------------*/
	    /* If Bandwidth Scalability Mode, read BWS_Configuration    */
	    /* ---------------------------------------------------------*/
	    BsGetBit(hdrStream, &temp, 2); *BWS_Configuration = temp;
	}
    }
}
/*======================================================================*/
/* Function Definition: Read_Narrowband_LSP                             */
/*======================================================================*/
void Read_NarrowBand_LSP
(
    BsBitStream *bitStream,           /* In: Bitstream                 */
    unsigned long indices[]           /* Out: indices to rfc_table[]   */
)
{
    /*==================================================================*/
    /*     Read the Parameters from the Bitstream                       */
    /*     These represent the packed LPC Indices                       */     
    /*==================================================================*/
	BsGetBit(bitStream, &indices[0], PAN_BIT_LSP22_0);
	BsGetBit(bitStream, &indices[1], PAN_BIT_LSP22_1);
	BsGetBit(bitStream, &indices[2], PAN_BIT_LSP22_2);
	BsGetBit(bitStream, &indices[3], PAN_BIT_LSP22_3);
	BsGetBit(bitStream, &indices[4], PAN_BIT_LSP22_4);
}

/*======================================================================*/
/* Function Definition: Read_Narrowband_LSP                             */
/*======================================================================*/
void Read_BandScalable_LSP
(
    BsBitStream *bitStream,           /* In: Bitstream                  */
    unsigned long indices[]           /* Out: indices                   */
)
{
    /*==================================================================*/
    /*     Read the Parameters from the Bitstream                       */
    /*     These represent the packed LPC Indices                       */     
    /*==================================================================*/
	BsGetBit(bitStream, &indices[0], 4);
	BsGetBit(bitStream, &indices[1], 7);
	BsGetBit(bitStream, &indices[2], 4);
	BsGetBit(bitStream, &indices[3], 6);
	BsGetBit(bitStream, &indices[4], 7);
	BsGetBit(bitStream, &indices[5], 4);
}

/*======================================================================*/
/* Function Definition: Read_Wideband_LSP                               */
/*======================================================================*/
void Read_Wideband_LSP
(
    BsBitStream *bitStream,           /* In: Bitstream                  */
    unsigned long indices[]           /* Out: indices                   */
)
{
	BsGetBit(bitStream, &indices[0], PAN_BIT_LSP_WL_0);
	BsGetBit(bitStream, &indices[1], PAN_BIT_LSP_WL_1);
	BsGetBit(bitStream, &indices[2], PAN_BIT_LSP_WL_2);
	BsGetBit(bitStream, &indices[3], PAN_BIT_LSP_WL_3);
	BsGetBit(bitStream, &indices[4], PAN_BIT_LSP_WL_4);
	BsGetBit(bitStream, &indices[5], PAN_BIT_LSP_WU_0);
	BsGetBit(bitStream, &indices[6], PAN_BIT_LSP_WU_1);
	BsGetBit(bitStream, &indices[7], PAN_BIT_LSP_WU_2);
	BsGetBit(bitStream, &indices[8], PAN_BIT_LSP_WU_3);
	BsGetBit(bitStream, &indices[9], PAN_BIT_LSP_WU_4);
}

/*======================================================================*/
/*      H I S T O R Y                                                   */
/*======================================================================*/
/* 07-06-96  R. Taori & A.Gerrits    Initial Version                    */
/* 18-09-96  R. Taori & A.Gerrits    MPEG bitstream used                */