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Diffstat (limited to 'media/libstagefright/codecs/amrnb/enc/src/convolve.cpp')
| -rw-r--r-- | media/libstagefright/codecs/amrnb/enc/src/convolve.cpp | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrnb/enc/src/convolve.cpp b/media/libstagefright/codecs/amrnb/enc/src/convolve.cpp new file mode 100644 index 0000000..e9ce7ba --- /dev/null +++ b/media/libstagefright/codecs/amrnb/enc/src/convolve.cpp @@ -0,0 +1,245 @@ +/* ------------------------------------------------------------------ + * 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. + * ------------------------------------------------------------------- + */ +/**************************************************************************************** +Portions of this file are derived from the following 3GPP standard: + + 3GPP TS 26.073 + ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec + Available from http://www.3gpp.org + +(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) +Permission to distribute, modify and use this file under the standard license +terms listed above has been obtained from the copyright holder. +****************************************************************************************/ +/* +------------------------------------------------------------------------------ + + + + Pathname: ./audio/gsm-amr/c/src/convolve.c + + Date: 06/19/2000 + +------------------------------------------------------------------------------ + REVISION HISTORY + + Description: Optimize for speed. Update to code template. + + Description: Added author name and date, fixed tabs, and added missing + sections. Updated Input/Output section. + + Description: Optimized code by calculating two convolution sums per iteration + of the outer loop, thereby, decreasing outer loop count by 2. + Updated input/output definitions to be the same as the assembly + file (convolve.asm). Left Pseudo-code section blank. + + Description: Deleted semi-colon in the Pointers modified section. + + Description: Synchronized file with UMTS version 3.2.0. Updated coding + template. Removed unnecessary include files. + + Description: Made the following changes per comments from Phase 2/3 review: + 1. Fixed typecasting issue with TI C compiler. + 2. Modified FOR loop to count down, wherever applicable. + + Description: Made the following changes + 1. Unrolled the correlation loop. + 2. Performed 2 correlation per pass per sample to avoid recalling + the same data twice. + 3. Eliminated math operations that check for saturation. + + Description: + 1. Modified loop counter, extra unrolling did speed up code + + Description: Replaced "int" and/or "char" with OSCL defined types. + + Description: Using inlines from fxp_arithmetic.h . + + Description: Replacing fxp_arithmetic.h with basic_op.h. + + Description: + +------------------------------------------------------------------------------ +*/ + +/*---------------------------------------------------------------------------- +; INCLUDES +----------------------------------------------------------------------------*/ +#include "typedef.h" +#include "convolve.h" +#include "basic_op.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 +----------------------------------------------------------------------------*/ + + +/* +------------------------------------------------------------------------------ + FUNCTION NAME: Convolve +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + + Inputs: + x = pointer to input vector of L elements of type Word16 + h = pointer to the filter's impulse response vector of L elements + of type Word16 + y = pointer to the output vector of L elements of type Word16 used for + storing the convolution of x and h; + L = Length of the convolution; type definition is Word16 + + Outputs: + y buffer contains the new convolution output + + Returns: + None + + Global Variables Used: + None + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + Perform the convolution between two vectors x[] and h[] and write the result + in the vector y[]. All vectors are of length L and only the first L samples + of the convolution are computed. + + The convolution is given by: + + y[n] = sum_{i=0}^{n} x[i] h[n-i], n=0,...,L-1 + +------------------------------------------------------------------------------ + REQUIREMENTS + + None + +------------------------------------------------------------------------------ + REFERENCES + + convolve.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 + +------------------------------------------------------------------------------ + PSEUDO-CODE + +void Convolve ( + Word16 x[], // (i) : input vector + Word16 h[], // (i) : impulse response + Word16 y[], // (o) : output vector + Word16 L // (i) : vector size +) +{ + Word16 i, n; + Word32 s; + + for (n = 0; n < L; n++) + { + s = 0; move32 (); + for (i = 0; i <= n; i++) + { + s = L_mac (s, x[i], h[n - i]); + } + s = L_shl (s, 3); + y[n] = extract_h (s); move16 (); + } + + return; +} + +------------------------------------------------------------------------------ + RESOURCES USED [optional] + + When the code is written for a specific target processor the + the resources used should be documented below. + + HEAP MEMORY USED: x bytes + + STACK MEMORY USED: x bytes + + CLOCK CYCLES: (cycle count equation for this function) + (variable + used to represent cycle count for each subroutine + called) + where: (cycle count variable) = cycle count for [subroutine + name] + +------------------------------------------------------------------------------ + CAUTION [optional] + [State any special notes, constraints or cautions for users of this function] + +------------------------------------------------------------------------------ +*/ + +void Convolve( + Word16 x[], /* (i) : input vector */ + Word16 h[], /* (i) : impulse response */ + Word16 y[], /* (o) : output vector */ + Word16 L /* (i) : vector size */ +) +{ + register Word16 i, n; + Word32 s1, s2; + + + for (n = 1; n < L; n = n + 2) + { + + h = h + n; + + s2 = ((Word32) * (x)) * *(h--); + s1 = ((Word32) * (x++)) * *(h); + + for (i = (n - 1) >> 1; i != 0; i--) + { + s2 = amrnb_fxp_mac_16_by_16bb((Word32) * (x), (Word32) * (h--), s2); + s1 = amrnb_fxp_mac_16_by_16bb((Word32) * (x++), (Word32) * (h), s1); + s2 = amrnb_fxp_mac_16_by_16bb((Word32) * (x), (Word32) * (h--), s2); + s1 = amrnb_fxp_mac_16_by_16bb((Word32) * (x++), (Word32) * (h), s1); + } + + s2 = amrnb_fxp_mac_16_by_16bb((Word32) * (x), (Word32) * (h), s2); + + *(y++) = (Word16)(s1 >> 12); + *(y++) = (Word16)(s2 >> 12); + + x = x - n; + + } + + return; +} |