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cocos-engine-external/sources/pvmp3dec/src/pvmp3_get_side_info.cpp

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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_get_side_info.cpp
Date: 09/21/2007
------------------------------------------------------------------------------
REVISION HISTORY
Description:
------------------------------------------------------------------------------
INPUT AND OUTPUT DEFINITIONS
Input
mp3SideInfo *si,
mp3Header *info, mp3 header information
uint32 *crc initialized crc value (if enabled)
Returns
mp3SideInfo *si, side information
------------------------------------------------------------------------------
FUNCTION DESCRIPTION
acquires side information
------------------------------------------------------------------------------
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_get_side_info.h"
#include "pvmp3_crc.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
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; 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
----------------------------------------------------------------------------*/
ERROR_CODE pvmp3_get_side_info(tmp3Bits *inputStream,
mp3SideInfo *si,
mp3Header *info,
uint32 *crc)
{
int32 ch, gr;
uint32 tmp;
int stereo = (info->mode == MPG_MD_MONO) ? 1 : 2;
if (info->version_x == MPEG_1)
{
if (stereo == 1)
{
tmp = getbits_crc(inputStream, 14, crc, info->error_protection);
si->main_data_begin = (tmp << 18) >> 23; /* 9 */
si->private_bits = (tmp << 23) >> 27; /* 5 */
}
else
{
tmp = getbits_crc(inputStream, 12, crc, info->error_protection);
si->main_data_begin = (tmp << 20) >> 23; /* 9 */
si->private_bits = (tmp << 23) >> 29; /* 3 */
}
for (ch = 0; ch < stereo; ch++)
{
tmp = getbits_crc(inputStream, 4, crc, info->error_protection);
si->ch[ch].scfsi[0] = (tmp << 28) >> 31; /* 1 */
si->ch[ch].scfsi[1] = (tmp << 29) >> 31; /* 1 */
si->ch[ch].scfsi[2] = (tmp << 30) >> 31; /* 1 */
si->ch[ch].scfsi[3] = tmp & 1; /* 1 */
}
for (gr = 0; gr < 2 ; gr++)
{
for (ch = 0; ch < stereo; ch++)
{
si->ch[ch].gran[gr].part2_3_length = getbits_crc(inputStream, 12, crc, info->error_protection);
tmp = getbits_crc(inputStream, 22, crc, info->error_protection);
si->ch[ch].gran[gr].big_values = (tmp << 10) >> 23; /* 9 */
si->ch[ch].gran[gr].global_gain = ((tmp << 19) >> 24) - 210; /* 8 */
si->ch[ch].gran[gr].scalefac_compress = (tmp << 27) >> 28; /* 4 */
si->ch[ch].gran[gr].window_switching_flag = tmp & 1; /* 1 */
if (si->ch[ch].gran[gr].window_switching_flag)
{
tmp = getbits_crc(inputStream, 22, crc, info->error_protection);
si->ch[ch].gran[gr].block_type = (tmp << 10) >> 30; /* 2 */;
si->ch[ch].gran[gr].mixed_block_flag = (tmp << 12) >> 31; /* 1 */;
si->ch[ch].gran[gr].table_select[0] = (tmp << 13) >> 27; /* 5 */;
si->ch[ch].gran[gr].table_select[1] = (tmp << 18) >> 27; /* 5 */;
si->ch[ch].gran[gr].subblock_gain[0] = (tmp << 23) >> 29; /* 3 */;
si->ch[ch].gran[gr].subblock_gain[1] = (tmp << 26) >> 29; /* 3 */;
si->ch[ch].gran[gr].subblock_gain[2] = (tmp << 29) >> 29; /* 3 */;
/* Set region_count parameters since they are implicit in this case. */
if (si->ch[ch].gran[gr].block_type == 0)
{
return(SIDE_INFO_ERROR);
}
else if ((si->ch[ch].gran[gr].block_type == 2)
&& (si->ch[ch].gran[gr].mixed_block_flag == 0))
{
si->ch[ch].gran[gr].region0_count = 8; /* MI 9; */
si->ch[ch].gran[gr].region1_count = 12;
}
else
{
si->ch[ch].gran[gr].region0_count = 7; /* MI 8; */
si->ch[ch].gran[gr].region1_count = 13;
}
}
else
{
tmp = getbits_crc(inputStream, 22, crc, info->error_protection);
si->ch[ch].gran[gr].table_select[0] = (tmp << 10) >> 27; /* 5 */;
si->ch[ch].gran[gr].table_select[1] = (tmp << 15) >> 27; /* 5 */;
si->ch[ch].gran[gr].table_select[2] = (tmp << 20) >> 27; /* 5 */;
si->ch[ch].gran[gr].region0_count = (tmp << 25) >> 28; /* 4 */;
si->ch[ch].gran[gr].region1_count = (tmp << 29) >> 29; /* 3 */;
si->ch[ch].gran[gr].block_type = 0;
}
tmp = getbits_crc(inputStream, 3, crc, info->error_protection);
si->ch[ch].gran[gr].preflag = (tmp << 29) >> 31; /* 1 */
si->ch[ch].gran[gr].scalefac_scale = (tmp << 30) >> 31; /* 1 */
si->ch[ch].gran[gr].count1table_select = tmp & 1; /* 1 */
}
}
}
else /* Layer 3 LSF */
{
si->main_data_begin = getbits_crc(inputStream, 8, crc, info->error_protection);
si->private_bits = getbits_crc(inputStream, stereo, crc, info->error_protection);
for (ch = 0; ch < stereo; ch++)
{
tmp = getbits_crc(inputStream, 21, crc, info->error_protection);
si->ch[ch].gran[0].part2_3_length = (tmp << 11) >> 20; /* 12 */
si->ch[ch].gran[0].big_values = (tmp << 23) >> 23; /* 9 */
tmp = getbits_crc(inputStream, 18, crc, info->error_protection);
si->ch[ch].gran[0].global_gain = ((tmp << 14) >> 24) - 210; /* 8 */
si->ch[ch].gran[0].scalefac_compress = (tmp << 22) >> 23; /* 9 */
si->ch[ch].gran[0].window_switching_flag = tmp & 1; /* 1 */
if (si->ch[ch].gran[0].window_switching_flag)
{
tmp = getbits_crc(inputStream, 22, crc, info->error_protection);
si->ch[ch].gran[0].block_type = (tmp << 10) >> 30; /* 2 */;
si->ch[ch].gran[0].mixed_block_flag = (tmp << 12) >> 31; /* 1 */;
si->ch[ch].gran[0].table_select[0] = (tmp << 13) >> 27; /* 5 */;
si->ch[ch].gran[0].table_select[1] = (tmp << 18) >> 27; /* 5 */;
si->ch[ch].gran[0].subblock_gain[0] = (tmp << 23) >> 29; /* 3 */;
si->ch[ch].gran[0].subblock_gain[1] = (tmp << 26) >> 29; /* 3 */;
si->ch[ch].gran[0].subblock_gain[2] = (tmp << 29) >> 29; /* 3 */;
/* Set region_count parameters since they are implicit in this case. */
if (si->ch[ch].gran[0].block_type == 0)
{
return(SIDE_INFO_ERROR);
}
else if ((si->ch[ch].gran[0].block_type == 2)
&& (si->ch[ch].gran[0].mixed_block_flag == 0))
{
si->ch[ch].gran[0].region0_count = 8; /* MI 9; */
si->ch[ch].gran[0].region1_count = 12;
}
else
{
si->ch[ch].gran[0].region0_count = 7; /* MI 8; */
si->ch[ch].gran[0].region1_count = 13;
}
}
else
{
tmp = getbits_crc(inputStream, 22, crc, info->error_protection);
si->ch[ch].gran[0].table_select[0] = (tmp << 10) >> 27; /* 5 */;
si->ch[ch].gran[0].table_select[1] = (tmp << 15) >> 27; /* 5 */;
si->ch[ch].gran[0].table_select[2] = (tmp << 20) >> 27; /* 5 */;
si->ch[ch].gran[0].region0_count = (tmp << 25) >> 28; /* 4 */;
si->ch[ch].gran[0].region1_count = (tmp << 29) >> 29; /* 3 */;
si->ch[ch].gran[0].block_type = 0;
}
tmp = getbits_crc(inputStream, 2, crc, info->error_protection);
si->ch[ch].gran[0].scalefac_scale = tmp >> 1; /* 1 */
si->ch[ch].gran[0].count1table_select = tmp & 1; /* 1 */
}
}
return (NO_DECODING_ERROR);
}
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