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diff --git a/media/libstagefright/codecs/aacdec/tns_ar_filter.cpp b/media/libstagefright/codecs/aacdec/tns_ar_filter.cpp
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--- a/media/libstagefright/codecs/aacdec/tns_ar_filter.cpp
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@@ -1,474 +0,0 @@
-/* ------------------------------------------------------------------
- * 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.
- * -------------------------------------------------------------------
- */
-/*
-
- Pathname: tns_ar_filter.c
-
-------------------------------------------------------------------------------
- REVISION HISTORY
-
- Description: Modified from original shareware code
-
- Description: Implemented 24-bit fixed point version
- Optimized C code
-
- Description:
- - Added OVERFLOW_SHIFT_DOWN to avoid overflow.
- - Increased precision by using the Q format of the LPC coefficient.
- - Modified interface to add LPC Q format and scratch memory
- for the state variables.
- - Added pv_memset to clear state filter
- - Updated format for comments (to PV standard)
- - Updated copyright notice
-
- Description:
- - Changed multiplication scheme to increase precision. This
- works better than older version.
-
- Description:
- - Include log2(order) as a scaling down parameter.
-
- Description:
- Modified to reflect code review comments
- - misspelled words, extra comments and explicit requirements
-
- Description:
- deleted comment about fix Q format (L 107)
-
- Description: Implemented a more efficient version, which eliminated the use
- of "scratch memory" via introducing a pointer that references the actual
- output.
-
- Description: Removed the parameter "scratch_Int32_buffer" as this space
- in memory is no longer needed by this function.
-
- Description: Removed references to "scratch_Int32_buffer" in the Inputs
- section.
-
- Description:
- Modified casting to ensure proper operations for different platforms
-
- Description:
- Per code review comment:
- Eliminated casting to UInt and Int in b_low and b_high, they are
- redundant and may add unncessary extra cycles in some platforms
-
- Description: Updated the SW template to include the full pathname to the
- source file and a slightly modified copyright header.
-
- Description: Changed the order of the unsigned * signed multiply so the
- casting to Int32 is performed on the unsigned operand.
-
- Description:
- Modified 32 by 16 bit multiplications to avoid unnecessary moves to
- registers. Also split the code (based on flag direction) to simplify
- pointer's updates
-
- Description:
-
-------------------------------------------------------------------------------
- INPUT AND OUTPUT DEFINITIONS
-
- Inputs:
- spec = spectral input to be shaped by the filter.
- Fixed point format
- Int32[]
- length = spec_length
-
- spec_length = length of spec array.
- const Int
-
- direction = direction for application of tns filter.
- +1 filters spectrum from low to high frequencies
- (first input to filter is spec[0])
- -1 filters spectrum from high to low frequencies
- (first input to filter is spec[spec_length-1])
- const Int
-
- lpc = array of lpc coefficients, minus lpc[0] which is assumed to be "1"
- Fixed point format
- const Int[]
- length = TNS_MAX_ORDER
-
- Q_lpc = Q format for the lpc coeffcients (for max. precision, it assumes
- that all 16 bits are used)
- const Int
-
- order = order of the TNS filter (Range of 1 - TNS_MAX_ORDER)
- Int
-
- Local Stores/Buffers/Pointers Needed:
- None
-
- Global Stores/Buffers/Pointers Needed:
- None
-
- Outputs:
- None
-
- Pointers and Buffers Modified:
- spec = contains spectral data after application of TNS filter
- Int32 array
- length = spec_length
-
-
- Local Stores Modified:
-
- Global Stores Modified:
-
-
-------------------------------------------------------------------------------
- FUNCTION DESCRIPTION
-
- A block of spectral data (Int32 spec[]) of length (const Int spec_length)
- is processed by a simple all-pole filter defined by
- LPC coefficients passed via (const Int lpc[])
-
- TNS filter equation
- y(n) = x(n) - lpc(2)*y(n-1) - ... - lpc(order+1)*y(n-order)
-
- The filter calculation is performed in place, i.e. the output is passed
- back to the calling function via (Int32 spec[])
-
- The filter's order is defined by the variable (const Int order)
- The direction of the filter's application is defined by (const Int inc)
-
-------------------------------------------------------------------------------
- REQUIREMENTS
-
- This function should match the functionality of the ISO code.
- The implementation does support filter orders bigger or equal to 1.
- The size of the spectral coeffcients has to be bigger or equal than 1.
-
-------------------------------------------------------------------------------
- REFERENCES
-
- (1) ISO/IEC 14496-3:1999(E)
- Part 3
- Subpart 4.6.8 (Temporal Noise Shaping)
-
- (2) MPEG-2 NBC Audio Decoder
- "This software module was originally developed by AT&T, Dolby
- Laboratories, Fraunhofer Gesellschaft IIS in the course of development
- of the MPEG-2 NBC/MPEG-4 Audio standard ISO/IEC 13818-7, 14496-1,2 and
- 3. This software module is an implementation of a part of one or more
- MPEG-2 NBC/MPEG-4 Audio tools as specified by the MPEG-2 NBC/MPEG-4
- Audio standard. ISO/IEC gives users of the MPEG-2 NBC/MPEG-4 Audio
- standards free license to this software module or modifications thereof
- for use in hardware or software products claiming conformance to the
- MPEG-2 NBC/MPEG-4 Audio standards. Those intending to use this software
- module in hardware or software products are advised that this 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-2 NBC/MPEG-4 Audio conforming products.The original
- developer 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 party
- from using the code for non MPEG-2 NBC/MPEG-4 Audio conforming products.
- This copyright notice must be included in all copies or derivative
- works."
- Copyright(c)1996.
-
-------------------------------------------------------------------------------
- PSEUDO-CODE
-
-
- FOR (i=0; i<order; i++)
- state[i] = 0;
- ENDFOR
-
- IF (inc == -1)
- THEN
- spec = spec + spec_length - 1;
- ENDIF
-
- FOR (i=0; i<spec_length; i++)
-
- y = *spec;
-
- FOR (j=0; j<order; j++)
-
- y -= lpc[j] * state[j];
-
- ENDFOR
-
- FOR (j=order-1; j>0; j--)
-
- state[j] = state[j-1];
-
- ENDFOR
-
- state[0] = y;
-
- *spec = y;
-
- spec = spec + inc;
-
- ENDFOR
-
-
-------------------------------------------------------------------------------
- RESOURCES USED
-
- When the code is written for a specific target processor
- the resources used should be documented below.
-
- STACK USAGE: [stack count for this module] + [variable to represent
- stack usage for each subroutine called]
-
- where: [stack usage variable] = stack usage for [subroutine
- name] (see [filename].ext)
-
- DATA MEMORY USED: x words
-
- PROGRAM MEMORY USED: x words
-
- CLOCK CYCLES: [cycle count equation for this module] + [variable
- used to represent cycle count for each subroutine
- called]
-
- where: [cycle count variable] = cycle count for [subroutine
- name] (see [filename].ext)
-
-------------------------------------------------------------------------------
-*/
-
-/*----------------------------------------------------------------------------
-; INCLUDES
-----------------------------------------------------------------------------*/
-#include "pv_audio_type_defs.h"
-#include "e_tns_const.h"
-#include "tns_ar_filter.h"
-#include "fxp_mul32.h"
-
-/*----------------------------------------------------------------------------
-; MACROS
-; Define module specific macros here
-----------------------------------------------------------------------------*/
-
-/*----------------------------------------------------------------------------
-; DEFINES
-; Include all pre-processor statements here. Include conditional
-; compile variables also.
-----------------------------------------------------------------------------*/
-#define MASK_LOW16 0xFFFF
-#define UPPER16 16
-
-/*----------------------------------------------------------------------------
-; 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
-----------------------------------------------------------------------------*/
-
-Int tns_ar_filter(
- Int32 spec[],
- const Int spec_length,
- const Int direction,
- const Int32 lpc[],
- const Int Q_lpc,
- const Int order)
-{
-
- Int i;
- Int j;
-
- /*
- * Multiplication related variables
- */
-
- Int32 temp;
-
- /*
- * Filter related variables
- */
- Int32 y0;
-
- /*
- * Circular buffer to hold the filter's state
- * (y[n-1],y[n-2],y[n-3],etc.)
- *
- * p_state and p_lpc should take advantage
- * of any special circular buffer instructions
- * if this code is hand-optimized in assembly.
- */
-
- Int32 *p_state = NULL;
-
- const Int32 *p_lpc;
-
-
- Int shift_up;
- Int shift_down_amount;
-
- /*
- * Pointer to the I/O memory space
- */
- Int32 *p_spec = spec;
-
-
- i = 0;
- j = order;
-
- /*
- * get the power of 2 that is bigger than the order
- * i is the bit counter and j is modified until exceed
- * the power of 2 corresponding to TNS_MAX_ORDER
- */
-
- while (j < 0x010)
- {
- j <<= 1;
- i++;
- }
-
- /*
- * 5 is the number of bits needed to represent 0x010
- * TNS_MAX_ORDER = 20, power of 2 that include 20 is 5
- */
- shift_down_amount = 4 - i;
-
- shift_up = UPPER16 - Q_lpc;
-
- /*
- * shift_down_amount == power of 2 that is bigger than the order - 1
- */
-
- shift_down_amount += shift_up;
-
- if (direction == -1)
- {
- p_spec += spec_length - 1;
-
- for (i = order; i != 0; i--)
- {
-
- y0 = *p_spec >> shift_down_amount;
-
- p_lpc = lpc;
-
- /* 32 by 32 bit multiplication */
- for (j = order; j > i; j--)
- {
- temp = *p_state++;
- y0 -= fxp_mul32_Q31(temp, *(p_lpc++)) << shift_up;
- }
-
- /*
- * Record the output in-place
- */
- p_state = p_spec;
- *(p_spec--) = y0;
-
- }
-
- if (spec_length > order)
- {
- for (i = (spec_length - order); i != 0; i--)
- {
- y0 = *p_spec >> shift_down_amount;
-
- p_lpc = &(lpc[0]);
-
- /* 32 by 32 bit multiplication */
- for (j = order; j != 0; j--)
- {
- temp = *p_state++;
- y0 -= fxp_mul32_Q31(temp, *(p_lpc++)) << shift_up;
- }
-
- /*
- * Record the output in-place
- */
- p_state = p_spec;
- *(p_spec--) = y0;
-
- } /* END for (i = (spec_length - order); i>0; i--) */
- }
-
- }
- else
- {
- for (i = order; i != 0; i--)
- {
-
- p_lpc = lpc;
-
- y0 = 0;
-
- /* 32 by 32 bit multiplication */
- for (j = order; j > i; j--)
- {
- y0 -= fxp_mul32_Q31(*p_state--, *(p_lpc++));
- }
-
- p_state = p_spec;
- /*
- * Record the output in-place
- */
- *(p_spec) = (*p_spec >> shift_down_amount) + (y0 << shift_up);
- p_spec++;
- }
-
- if (spec_length > order)
- {
- for (i = (spec_length - order); i != 0; i--)
- {
- p_lpc = lpc;
-
- y0 = 0;
-
- /* 32 by 32 bit multiplication */
- for (j = order; j != 0; j--)
- {
- y0 -= fxp_mul32_Q31(*p_state--, *(p_lpc++));
- }
-
- p_state = p_spec;
- /*
- * Record the output in-place
- */
- *(p_spec) = (*p_spec >> shift_down_amount) + (y0 << shift_up);
- p_spec++;
-
- } /* END for (i = (spec_length - order); i>0; i--) */
- }
- }
-
- return(shift_down_amount);
-
-
-} /* tns_ar_filter */
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