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/* ------------------------------------------------------------------
* Copyright (C) 1998-2009 PacketVideo
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied.
* See the License for the specific language governing permissions
* and limitations under the License.
* -------------------------------------------------------------------
*/
/*
------------------------------------------------------------------------------
PacketVideo Corp.
MP3 Decoder Library
Filename: pvmp3_mpeg2_get_scale_data.cpp
Date: 09/21/2007
------------------------------------------------------------------------------
REVISION HISTORY
Description:
------------------------------------------------------------------------------
INPUT AND OUTPUT DEFINITIONS
Input
mp3SideInfo *si, side information
int32 gr, granule
int32 ch, channel
mp3Header *info, mp3 header information
uint32 *scalefac_buffer,
uint32 *scalefac_IIP_buffer,
tbits *pMainData bit stream Data
Returns
uint32 *scalefac_buffer, acquired scale band data
uint32 *scalefac_IIP_buffer, auxiliary scale data
------------------------------------------------------------------------------
FUNCTION DESCRIPTION
get scale data for mpeg2 layer III LSF extension
------------------------------------------------------------------------------
REQUIREMENTS
------------------------------------------------------------------------------
REFERENCES
[1] ISO MPEG Audio Subgroup Software Simulation Group (1996)
ISO 13818-3 MPEG-2 Audio Decoder - Lower Sampling Frequency Extension
------------------------------------------------------------------------------
PSEUDO-CODE
------------------------------------------------------------------------------
*/
/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "pvmp3_mpeg2_get_scale_data.h"
#include "pvmp3_getbits.h"
/*----------------------------------------------------------------------------
; MACROS
; Define module specific macros here
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; DEFINES
; Include all pre-processor statements here. Include conditional
; compile variables also.
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; LOCAL FUNCTION DEFINITIONS
; Function Prototype declaration
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; LOCAL STORE/BUFFER/POINTER DEFINITIONS
; Variable declaration - defined here and used outside this module
----------------------------------------------------------------------------*/
const uint32 nr_of_sfb_block[6][3][4] =
{ {{ 6, 5, 5, 5}, { 9, 9, 9, 9}, { 6, 9, 9, 9}},
{{ 6, 5, 7, 3}, { 9, 9, 12, 6}, { 6, 9, 12, 6}},
{{11, 10, 0, 0}, { 18, 18, 0, 0}, {15, 18, 0, 0}},
{{ 7, 7, 7, 0}, { 12, 12, 12, 0}, { 6, 15, 12, 0}},
{{ 6, 6, 6, 3}, { 12, 9, 9, 6}, { 6, 12, 9, 6}},
{{ 8, 8, 5, 0}, { 15, 12, 9, 0}, { 6, 18, 9, 0}}
};
/*----------------------------------------------------------------------------
; EXTERNAL FUNCTION REFERENCES
; Declare functions defined elsewhere and referenced in this module
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
; Declare variables used in this module but defined elsewhere
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; FUNCTION CODE
----------------------------------------------------------------------------*/
void pvmp3_mpeg2_get_scale_data(mp3SideInfo *si,
int32 gr,
int32 ch,
mp3Header *info,
uint32 *scalefac_buffer,
uint32 *scalefac_IIP_buffer,
tmp3Bits *pMainData)
{
int16 i;
int16 j;
int16 k;
int16 blocktypenumber = 0;
int16 blocknumber = 0;
granuleInfo *gr_info = &(si->ch[ch].gran[gr]);
uint32 scalefac_comp, int_scalefac_comp, new_slen[4];
scalefac_comp = gr_info->scalefac_compress;
if ((((info->mode_ext &1)) && (ch == 1)))
{
/* intensity_scale = scalefac_comp %2; */
int_scalefac_comp = scalefac_comp >> 1;
if (int_scalefac_comp < 180)
{
new_slen[0] = int_scalefac_comp / 36;
new_slen[1] = (int_scalefac_comp % 36) / 6;
new_slen[2] = int_scalefac_comp % 6;
blocknumber = 3;
}
else if (int_scalefac_comp < 244)
{
int_scalefac_comp -= 180;
new_slen[0] = (int_scalefac_comp & 63) >> 4;
new_slen[1] = (int_scalefac_comp & 15) >> 2;
new_slen[2] = int_scalefac_comp & 3;
blocknumber = 4;
}
else if (int_scalefac_comp <= 255)
{
int_scalefac_comp -= 244;
new_slen[0] = (int_scalefac_comp) / 3;
new_slen[1] = (int_scalefac_comp) % 3;
new_slen[2] = 0;
blocknumber = 5;
}
new_slen[3] = 0;
si->ch[ch].gran[gr].preflag = 0;
}
else
{
if (scalefac_comp < 400)
{
new_slen[0] = (scalefac_comp >> 4) / 5;
new_slen[1] = (scalefac_comp >> 4) % 5;
new_slen[2] = (scalefac_comp & 15) >> 2 ;
new_slen[3] = (scalefac_comp & 3);
si->ch[ch].gran[gr].preflag = 0;
blocknumber = 0;
}
else if (scalefac_comp < 500)
{
scalefac_comp -= 400;
new_slen[0] = (scalefac_comp >> 2) / 5;
new_slen[1] = (scalefac_comp >> 2) % 5;
new_slen[2] = scalefac_comp & 3;
new_slen[3] = 0;
si->ch[ch].gran[gr].preflag = 0;
blocknumber = 1;
}
else if (scalefac_comp < 512)
{
scalefac_comp -= 500;
new_slen[0] = scalefac_comp / 3;
new_slen[1] = scalefac_comp % 3;
new_slen[2] = 0 ;
new_slen[3] = 0;
si->ch[ch].gran[gr].preflag = 1;
blocknumber = 2;
}
}
if (gr_info->block_type == 2)
{
if (gr_info->mixed_block_flag)
{
blocktypenumber = 2;
}
else
{
blocktypenumber = 1;
}
}
k = 0;
for (i = 0; i < 4; i++)
{
if (new_slen[i])
{
for (j = 0; j < (int16)nr_of_sfb_block[blocknumber][blocktypenumber][i]; j++)
{
scalefac_buffer[k] = getNbits(pMainData, new_slen[i]);
scalefac_IIP_buffer[k] = (1L << new_slen[i]) - 1;
k++;
}
}
else
{
for (j = 0; j < (int16)nr_of_sfb_block[blocknumber][blocktypenumber][i]; j++)
{
scalefac_buffer[k] = 0;
scalefac_IIP_buffer[k] = 0;
k++;
}
}
}
}
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