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Diffstat (limited to 'media/libstagefright/codecs/amrnb/enc/src/autocorr.cpp')
| -rw-r--r-- | media/libstagefright/codecs/amrnb/enc/src/autocorr.cpp | 459 |
1 files changed, 459 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrnb/enc/src/autocorr.cpp b/media/libstagefright/codecs/amrnb/enc/src/autocorr.cpp new file mode 100644 index 0000000..0d3acac --- /dev/null +++ b/media/libstagefright/codecs/amrnb/enc/src/autocorr.cpp @@ -0,0 +1,459 @@ +/* ------------------------------------------------------------------ + * 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/autocorr.c + + Date: 05/15/2000 + +------------------------------------------------------------------------------ + REVISION HISTORY + + Description: Put into template...starting optimization. + + Description: Removed call to mult_r routine. + + Description: Modified Input/Output Definitions section to comply with the + current template. Fixed tabs. + + Description: Updated Input/Output definitions by making them more + descriptive. + + Description: Synchronized file with UMTS version 3.2.0. Updated coding + template. + + Description: Made the following changes per comments from Phase 2/3 review: + 1. Added full pathname of file. + 2. Fixed typecasting issue with TI compiler. + 3. Modified FOR loops to count down. + 4. Added comment to the code. + + Description: Removed extern to global paramter (Flag Overflow) and replaced + by passing in a pointer to Overflow. Also, made several small changes to + bring code more in line with PV Standards. + + Description: + 1. Added pointer to avoid adding offsets in every pass + 2. Break last loop in two nested loop to speed up processing + 3. Removed extra check for overflow by doing scaling right + after overflow is detected. + 4. Eliminated calls to basic operations (like extract) not + needed because of the nature of the number (all bounded) + + Description: + 1. Fixed for: + overflow check was looking for positive number before a left + shift. When numbers were big enough, positive numbers after + shifted became negative, causing a 1/0 division). + Fixed so now it checks for numbers lesser than 0x40000000 + before the left shift + + Description: + 1.Modified check for saturation to match bit exact test. + Also, when saturation is reached, a faster loop is used + (with no energy accumulation) to speed up processing + + + Description: + 1.Added pointer initialization to for loop when saturation + is found. This because some compiler ( like Vcpp in release + mode) when optimizing code, may remove pointer information + once the loop is broken. + + Description: Added casting to eliminate warnings + + 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 "autocorr.h" +#include "typedef.h" +#include "basic_op.h" +#include "oper_32b.h" +#include "cnst.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 NAME: Autocorr +---------------------------------------------------------------------------- + INPUT AND OUTPUT DEFINITIONS + + Inputs: + x = buffer of input signals of type Word16 + m = LPC order of type Word16 + wind = buffer of window signals of type Word16 + r_h = buffer containing the high word of the autocorrelation values + of type Word16 + r_l = buffer containing the low word of the autocorrelation values + of type Word16 + + pOverflow = pointer to variable of type Flag *, which indicates if + overflow occurs. + + Outputs: + r_h buffer contains the high word of the new autocorrelation values + r_l buffer contains the low word of the new autocorrelation values + pOverflow -> 1 if overflow occurs. + + Returns: + norm = normalized autocorrelation at lag zero of type Word16 + + Global Variables Used: + None + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + This function windows the input signal with the provided window + then calculates the autocorrelation values for lags of 0,1,...m, + where m is the passed in LPC order. + +------------------------------------------------------------------------------ + REQUIREMENTS + + None. + +------------------------------------------------------------------------------ + REFERENCES + + autocorr.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 + +------------------------------------------------------------------------------ + PSEUDO-CODE + +Word16 Autocorr ( + Word16 x[], // (i) : Input signal (L_WINDOW) + Word16 m, // (i) : LPC order + Word16 r_h[], // (o) : Autocorrelations (msb) + Word16 r_l[], // (o) : Autocorrelations (lsb) + const Word16 wind[] // (i) : window for LPC analysis (L_WINDOW) +) +{ + Word16 i, j, norm; + Word16 y[L_WINDOW]; + Word32 sum; + Word16 overfl, overfl_shft; + + // Windowing of signal + + for (i = 0; i < L_WINDOW; i++) + { + y[i] = mult_r (x[i], wind[i]); + } + + // Compute r[0] and test for overflow + + overfl_shft = 0; + + do + { + overfl = 0; + sum = 0L; + + for (i = 0; i < L_WINDOW; i++) + { + sum = L_mac (sum, y[i], y[i]); + } + + // If overflow divide y[] by 4 + + if (L_sub (sum, MAX_32) == 0L) + { + overfl_shft = add (overfl_shft, 4); + overfl = 1; // Set the overflow flag + + for (i = 0; i < L_WINDOW; i++) + { + y[i] = shr (y[i], 2); + } + } + } + while (overfl != 0); + + sum = L_add (sum, 1L); // Avoid the case of all zeros + + // Normalization of r[0] + + norm = norm_l (sum); + sum = L_shl (sum, norm); + L_Extract (sum, &r_h[0], &r_l[0]); // Put in DPF format (see oper_32b) + + // r[1] to r[m] + + for (i = 1; i <= m; i++) + { + sum = 0; + + for (j = 0; j < L_WINDOW - i; j++) + { + sum = L_mac (sum, y[j], y[j + i]); + } + + sum = L_shl (sum, norm); + L_Extract (sum, &r_h[i], &r_l[i]); + } + + norm = sub (norm, overfl_shft); + + return norm; +} + + +------------------------------------------------------------------------------ + 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] + +------------------------------------------------------------------------------ +*/ + +Word16 Autocorr( + Word16 x[], /* (i) : Input signal (L_WINDOW) */ + Word16 m, /* (i) : LPC order */ + Word16 r_h[], /* (o) : Autocorrelations (msb) */ + Word16 r_l[], /* (o) : Autocorrelations (lsb) */ + const Word16 wind[], /* (i) : window for LPC analysis (L_WINDOW) */ + Flag *pOverflow /* (o) : indicates overflow */ +) +{ + register Word16 i; + register Word16 j; + register Word16 norm; + + Word16 y[L_WINDOW]; + Word32 sum; + Word16 overfl_shft; + + + /* Added for optimization */ + + + Word16 temp; + Word16 *p_x; + Word16 *p_y; + Word16 *p_y_1; + Word16 *p_y_ref; + Word16 *p_rh; + Word16 *p_rl; + const Word16 *p_wind; + p_y = y; + p_x = x; + p_wind = wind; + /* + * Windowing of the signal + */ + + OSCL_UNUSED_ARG(pOverflow); + + sum = 0L; + j = 0; + + for (i = L_WINDOW; i != 0; i--) + { + temp = (amrnb_fxp_mac_16_by_16bb((Word32) * (p_x++), (Word32) * (p_wind++), 0x04000)) >> 15; + *(p_y++) = temp; + + sum += ((Word32)temp * temp) << 1; + if (sum < 0) + { + /* + * if oveflow exist, then stop accumulation + */ + j = 1; + break; + } + + } + /* + * if oveflow existed, complete windowing operation + * without computing energy + */ + + if (j) + { + p_y = &y[L_WINDOW-i]; + p_x = &x[L_WINDOW-i]; + p_wind = &wind[L_WINDOW-i]; + + for (; i != 0; i--) + { + temp = (amrnb_fxp_mac_16_by_16bb((Word32) * (p_x++), (Word32) * (p_wind++), 0x04000)) >> 15; + *(p_y++) = temp; + } + } + + + /* + * Compute r[0] and test for overflow + */ + + overfl_shft = 0; + + /* + * scale down by 1/4 only when needed + */ + while (j == 1) + { + /* If overflow divide y[] by 4 */ + /* FYI: For better resolution, we could */ + /* divide y[] by 2 */ + overfl_shft += 4; + p_y = &y[0]; + sum = 0L; + + for (i = (L_WINDOW >> 1); i != 0 ; i--) + { + temp = *p_y >> 2; + *(p_y++) = temp; + sum += ((Word32)temp * temp) << 1; + temp = *p_y >> 2; + *(p_y++) = temp; + sum += ((Word32)temp * temp) << 1; + } + if (sum > 0) + { + j = 0; + } + + } + + sum += 1L; /* Avoid the case of all zeros */ + + /* Normalization of r[0] */ + + norm = norm_l(sum); + + sum <<= norm; + + /* Put in DPF format (see oper_32b) */ + r_h[0] = (Word16)(sum >> 16); + r_l[0] = (Word16)((sum >> 1) - ((Word32)(r_h[0]) << 15)); + + /* r[1] to r[m] */ + + p_y_ref = &y[L_WINDOW - 1 ]; + p_rh = &r_h[m]; + p_rl = &r_l[m]; + + for (i = m; i > 0; i--) + { + sum = 0; + + p_y = &y[L_WINDOW - i - 1]; + p_y_1 = p_y_ref; + + for (j = (L_WINDOW - i - 1) >> 1; j != 0; j--) + { + sum = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y--), (Word32) * (p_y_1--), sum); + sum = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y--), (Word32) * (p_y_1--), sum); + } + + sum = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y--), (Word32) * (p_y_1--), sum); + + if (((L_WINDOW - i - 1) & 1)) + { + sum = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y--), (Word32) * (p_y_1--), sum); + } + + sum <<= (norm + 1); + + *(p_rh) = (Word16)(sum >> 16); + *(p_rl--) = (Word16)((sum >> 1) - ((Word32) * (p_rh--) << 15)); + + } + + norm -= overfl_shft; + + return (norm); + +} /* Autocorr */ |