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Diffstat (limited to 'third_party/webrtc/src/webrtc/common_audio/signal_processing/include/signal_processing_library.h')
| -rw-r--r-- | third_party/webrtc/src/webrtc/common_audio/signal_processing/include/signal_processing_library.h | 1645 |
1 files changed, 1645 insertions, 0 deletions
diff --git a/third_party/webrtc/src/webrtc/common_audio/signal_processing/include/signal_processing_library.h b/third_party/webrtc/src/webrtc/common_audio/signal_processing/include/signal_processing_library.h new file mode 100644 index 00000000..2e96883e --- /dev/null +++ b/third_party/webrtc/src/webrtc/common_audio/signal_processing/include/signal_processing_library.h @@ -0,0 +1,1645 @@ +/* + * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + + +/* + * This header file includes all of the fix point signal processing library (SPL) function + * descriptions and declarations. + * For specific function calls, see bottom of file. + */ + +#ifndef WEBRTC_SPL_SIGNAL_PROCESSING_LIBRARY_H_ +#define WEBRTC_SPL_SIGNAL_PROCESSING_LIBRARY_H_ + +#include <string.h> +#include "webrtc/typedefs.h" + +// Macros specific for the fixed point implementation +#define WEBRTC_SPL_WORD16_MAX 32767 +#define WEBRTC_SPL_WORD16_MIN -32768 +#define WEBRTC_SPL_WORD32_MAX (int32_t)0x7fffffff +#define WEBRTC_SPL_WORD32_MIN (int32_t)0x80000000 +#define WEBRTC_SPL_MAX_LPC_ORDER 14 +#define WEBRTC_SPL_MIN(A, B) (A < B ? A : B) // Get min value +#define WEBRTC_SPL_MAX(A, B) (A > B ? A : B) // Get max value +// TODO(kma/bjorn): For the next two macros, investigate how to correct the code +// for inputs of a = WEBRTC_SPL_WORD16_MIN or WEBRTC_SPL_WORD32_MIN. +#define WEBRTC_SPL_ABS_W16(a) \ + (((int16_t)a >= 0) ? ((int16_t)a) : -((int16_t)a)) +#define WEBRTC_SPL_ABS_W32(a) \ + (((int32_t)a >= 0) ? ((int32_t)a) : -((int32_t)a)) + +#define WEBRTC_SPL_MUL(a, b) \ + ((int32_t) ((int32_t)(a) * (int32_t)(b))) +#define WEBRTC_SPL_UMUL(a, b) \ + ((uint32_t) ((uint32_t)(a) * (uint32_t)(b))) +#define WEBRTC_SPL_UMUL_32_16(a, b) \ + ((uint32_t) ((uint32_t)(a) * (uint16_t)(b))) +#define WEBRTC_SPL_MUL_16_U16(a, b) \ + ((int32_t)(int16_t)(a) * (uint16_t)(b)) + +#ifndef WEBRTC_ARCH_ARM_V7 +// For ARMv7 platforms, these are inline functions in spl_inl_armv7.h +#ifndef MIPS32_LE +// For MIPS platforms, these are inline functions in spl_inl_mips.h +#define WEBRTC_SPL_MUL_16_16(a, b) \ + ((int32_t) (((int16_t)(a)) * ((int16_t)(b)))) +#define WEBRTC_SPL_MUL_16_32_RSFT16(a, b) \ + (WEBRTC_SPL_MUL_16_16(a, b >> 16) \ + + ((WEBRTC_SPL_MUL_16_16(a, (b & 0xffff) >> 1) + 0x4000) >> 15)) +#endif +#endif + +#define WEBRTC_SPL_MUL_16_32_RSFT11(a, b) \ + ((WEBRTC_SPL_MUL_16_16(a, (b) >> 16) << 5) \ + + (((WEBRTC_SPL_MUL_16_U16(a, (uint16_t)(b)) >> 1) + 0x0200) >> 10)) +#define WEBRTC_SPL_MUL_16_32_RSFT14(a, b) \ + ((WEBRTC_SPL_MUL_16_16(a, (b) >> 16) << 2) \ + + (((WEBRTC_SPL_MUL_16_U16(a, (uint16_t)(b)) >> 1) + 0x1000) >> 13)) +#define WEBRTC_SPL_MUL_16_32_RSFT15(a, b) \ + ((WEBRTC_SPL_MUL_16_16(a, (b) >> 16) << 1) \ + + (((WEBRTC_SPL_MUL_16_U16(a, (uint16_t)(b)) >> 1) + 0x2000) >> 14)) + +#define WEBRTC_SPL_MUL_16_16_RSFT(a, b, c) \ + (WEBRTC_SPL_MUL_16_16(a, b) >> (c)) + +#define WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(a, b, c) \ + ((WEBRTC_SPL_MUL_16_16(a, b) + ((int32_t) \ + (((int32_t)1) << ((c) - 1)))) >> (c)) + +// C + the 32 most significant bits of A * B +#define WEBRTC_SPL_SCALEDIFF32(A, B, C) \ + (C + (B >> 16) * A + (((uint32_t)(0x0000FFFF & B) * A) >> 16)) + +#define WEBRTC_SPL_SAT(a, b, c) (b > a ? a : b < c ? c : b) + +// Shifting with negative numbers allowed +// Positive means left shift +#define WEBRTC_SPL_SHIFT_W32(x, c) \ + (((c) >= 0) ? ((x) << (c)) : ((x) >> (-(c)))) + +// Shifting with negative numbers not allowed +// We cannot do casting here due to signed/unsigned problem +#define WEBRTC_SPL_LSHIFT_W32(x, c) ((x) << (c)) + +#define WEBRTC_SPL_RSHIFT_U32(x, c) ((uint32_t)(x) >> (c)) + +#define WEBRTC_SPL_RAND(a) \ + ((int16_t)((((int16_t)a * 18816) >> 7) & 0x00007fff)) + +#ifdef __cplusplus +extern "C" { +#endif + +#define WEBRTC_SPL_MEMCPY_W16(v1, v2, length) \ + memcpy(v1, v2, (length) * sizeof(int16_t)) + +// inline functions: +#include "webrtc/common_audio/signal_processing/include/spl_inl.h" + +// Initialize SPL. Currently it contains only function pointer initialization. +// If the underlying platform is known to be ARM-Neon (WEBRTC_HAS_NEON defined), +// the pointers will be assigned to code optimized for Neon; otherwise +// if run-time Neon detection (WEBRTC_DETECT_NEON) is enabled, the pointers +// will be assigned to either Neon code or generic C code; otherwise, generic C +// code will be assigned. +// Note that this function MUST be called in any application that uses SPL +// functions. +void WebRtcSpl_Init(); + +int16_t WebRtcSpl_GetScalingSquare(int16_t* in_vector, + size_t in_vector_length, + size_t times); + +// Copy and set operations. Implementation in copy_set_operations.c. +// Descriptions at bottom of file. +void WebRtcSpl_MemSetW16(int16_t* vector, + int16_t set_value, + size_t vector_length); +void WebRtcSpl_MemSetW32(int32_t* vector, + int32_t set_value, + size_t vector_length); +void WebRtcSpl_MemCpyReversedOrder(int16_t* out_vector, + int16_t* in_vector, + size_t vector_length); +void WebRtcSpl_CopyFromEndW16(const int16_t* in_vector, + size_t in_vector_length, + size_t samples, + int16_t* out_vector); +void WebRtcSpl_ZerosArrayW16(int16_t* vector, + size_t vector_length); +void WebRtcSpl_ZerosArrayW32(int32_t* vector, + size_t vector_length); +// End: Copy and set operations. + + +// Minimum and maximum operation functions and their pointers. +// Implementation in min_max_operations.c. + +// Returns the largest absolute value in a signed 16-bit vector. +// +// Input: +// - vector : 16-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Maximum absolute value in vector. +typedef int16_t (*MaxAbsValueW16)(const int16_t* vector, size_t length); +extern MaxAbsValueW16 WebRtcSpl_MaxAbsValueW16; +int16_t WebRtcSpl_MaxAbsValueW16C(const int16_t* vector, size_t length); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int16_t WebRtcSpl_MaxAbsValueW16Neon(const int16_t* vector, size_t length); +#endif +#if defined(MIPS32_LE) +int16_t WebRtcSpl_MaxAbsValueW16_mips(const int16_t* vector, size_t length); +#endif + +// Returns the largest absolute value in a signed 32-bit vector. +// +// Input: +// - vector : 32-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Maximum absolute value in vector. +typedef int32_t (*MaxAbsValueW32)(const int32_t* vector, size_t length); +extern MaxAbsValueW32 WebRtcSpl_MaxAbsValueW32; +int32_t WebRtcSpl_MaxAbsValueW32C(const int32_t* vector, size_t length); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int32_t WebRtcSpl_MaxAbsValueW32Neon(const int32_t* vector, size_t length); +#endif +#if defined(MIPS_DSP_R1_LE) +int32_t WebRtcSpl_MaxAbsValueW32_mips(const int32_t* vector, size_t length); +#endif + +// Returns the maximum value of a 16-bit vector. +// +// Input: +// - vector : 16-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Maximum sample value in |vector|. +typedef int16_t (*MaxValueW16)(const int16_t* vector, size_t length); +extern MaxValueW16 WebRtcSpl_MaxValueW16; +int16_t WebRtcSpl_MaxValueW16C(const int16_t* vector, size_t length); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int16_t WebRtcSpl_MaxValueW16Neon(const int16_t* vector, size_t length); +#endif +#if defined(MIPS32_LE) +int16_t WebRtcSpl_MaxValueW16_mips(const int16_t* vector, size_t length); +#endif + +// Returns the maximum value of a 32-bit vector. +// +// Input: +// - vector : 32-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Maximum sample value in |vector|. +typedef int32_t (*MaxValueW32)(const int32_t* vector, size_t length); +extern MaxValueW32 WebRtcSpl_MaxValueW32; +int32_t WebRtcSpl_MaxValueW32C(const int32_t* vector, size_t length); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int32_t WebRtcSpl_MaxValueW32Neon(const int32_t* vector, size_t length); +#endif +#if defined(MIPS32_LE) +int32_t WebRtcSpl_MaxValueW32_mips(const int32_t* vector, size_t length); +#endif + +// Returns the minimum value of a 16-bit vector. +// +// Input: +// - vector : 16-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Minimum sample value in |vector|. +typedef int16_t (*MinValueW16)(const int16_t* vector, size_t length); +extern MinValueW16 WebRtcSpl_MinValueW16; +int16_t WebRtcSpl_MinValueW16C(const int16_t* vector, size_t length); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int16_t WebRtcSpl_MinValueW16Neon(const int16_t* vector, size_t length); +#endif +#if defined(MIPS32_LE) +int16_t WebRtcSpl_MinValueW16_mips(const int16_t* vector, size_t length); +#endif + +// Returns the minimum value of a 32-bit vector. +// +// Input: +// - vector : 32-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Minimum sample value in |vector|. +typedef int32_t (*MinValueW32)(const int32_t* vector, size_t length); +extern MinValueW32 WebRtcSpl_MinValueW32; +int32_t WebRtcSpl_MinValueW32C(const int32_t* vector, size_t length); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int32_t WebRtcSpl_MinValueW32Neon(const int32_t* vector, size_t length); +#endif +#if defined(MIPS32_LE) +int32_t WebRtcSpl_MinValueW32_mips(const int32_t* vector, size_t length); +#endif + +// Returns the vector index to the largest absolute value of a 16-bit vector. +// +// Input: +// - vector : 16-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Index to the maximum absolute value in vector. +// If there are multiple equal maxima, return the index of the +// first. -32768 will always have precedence over 32767 (despite +// -32768 presenting an int16 absolute value of 32767). +size_t WebRtcSpl_MaxAbsIndexW16(const int16_t* vector, size_t length); + +// Returns the vector index to the maximum sample value of a 16-bit vector. +// +// Input: +// - vector : 16-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Index to the maximum value in vector (if multiple +// indexes have the maximum, return the first). +size_t WebRtcSpl_MaxIndexW16(const int16_t* vector, size_t length); + +// Returns the vector index to the maximum sample value of a 32-bit vector. +// +// Input: +// - vector : 32-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Index to the maximum value in vector (if multiple +// indexes have the maximum, return the first). +size_t WebRtcSpl_MaxIndexW32(const int32_t* vector, size_t length); + +// Returns the vector index to the minimum sample value of a 16-bit vector. +// +// Input: +// - vector : 16-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Index to the mimimum value in vector (if multiple +// indexes have the minimum, return the first). +size_t WebRtcSpl_MinIndexW16(const int16_t* vector, size_t length); + +// Returns the vector index to the minimum sample value of a 32-bit vector. +// +// Input: +// - vector : 32-bit input vector. +// - length : Number of samples in vector. +// +// Return value : Index to the mimimum value in vector (if multiple +// indexes have the minimum, return the first). +size_t WebRtcSpl_MinIndexW32(const int32_t* vector, size_t length); + +// End: Minimum and maximum operations. + + +// Vector scaling operations. Implementation in vector_scaling_operations.c. +// Description at bottom of file. +void WebRtcSpl_VectorBitShiftW16(int16_t* out_vector, + size_t vector_length, + const int16_t* in_vector, + int16_t right_shifts); +void WebRtcSpl_VectorBitShiftW32(int32_t* out_vector, + size_t vector_length, + const int32_t* in_vector, + int16_t right_shifts); +void WebRtcSpl_VectorBitShiftW32ToW16(int16_t* out_vector, + size_t vector_length, + const int32_t* in_vector, + int right_shifts); +void WebRtcSpl_ScaleVector(const int16_t* in_vector, + int16_t* out_vector, + int16_t gain, + size_t vector_length, + int16_t right_shifts); +void WebRtcSpl_ScaleVectorWithSat(const int16_t* in_vector, + int16_t* out_vector, + int16_t gain, + size_t vector_length, + int16_t right_shifts); +void WebRtcSpl_ScaleAndAddVectors(const int16_t* in_vector1, + int16_t gain1, int right_shifts1, + const int16_t* in_vector2, + int16_t gain2, int right_shifts2, + int16_t* out_vector, + size_t vector_length); + +// The functions (with related pointer) perform the vector operation: +// out_vector[k] = ((scale1 * in_vector1[k]) + (scale2 * in_vector2[k]) +// + round_value) >> right_shifts, +// where round_value = (1 << right_shifts) >> 1. +// +// Input: +// - in_vector1 : Input vector 1 +// - in_vector1_scale : Gain to be used for vector 1 +// - in_vector2 : Input vector 2 +// - in_vector2_scale : Gain to be used for vector 2 +// - right_shifts : Number of right bit shifts to be applied +// - length : Number of elements in the input vectors +// +// Output: +// - out_vector : Output vector +// Return value : 0 if OK, -1 if (in_vector1 == NULL +// || in_vector2 == NULL || out_vector == NULL +// || length <= 0 || right_shift < 0). +typedef int (*ScaleAndAddVectorsWithRound)(const int16_t* in_vector1, + int16_t in_vector1_scale, + const int16_t* in_vector2, + int16_t in_vector2_scale, + int right_shifts, + int16_t* out_vector, + size_t length); +extern ScaleAndAddVectorsWithRound WebRtcSpl_ScaleAndAddVectorsWithRound; +int WebRtcSpl_ScaleAndAddVectorsWithRoundC(const int16_t* in_vector1, + int16_t in_vector1_scale, + const int16_t* in_vector2, + int16_t in_vector2_scale, + int right_shifts, + int16_t* out_vector, + size_t length); +#if defined(MIPS_DSP_R1_LE) +int WebRtcSpl_ScaleAndAddVectorsWithRound_mips(const int16_t* in_vector1, + int16_t in_vector1_scale, + const int16_t* in_vector2, + int16_t in_vector2_scale, + int right_shifts, + int16_t* out_vector, + size_t length); +#endif +// End: Vector scaling operations. + +// iLBC specific functions. Implementations in ilbc_specific_functions.c. +// Description at bottom of file. +void WebRtcSpl_ReverseOrderMultArrayElements(int16_t* out_vector, + const int16_t* in_vector, + const int16_t* window, + size_t vector_length, + int16_t right_shifts); +void WebRtcSpl_ElementwiseVectorMult(int16_t* out_vector, + const int16_t* in_vector, + const int16_t* window, + size_t vector_length, + int16_t right_shifts); +void WebRtcSpl_AddVectorsAndShift(int16_t* out_vector, + const int16_t* in_vector1, + const int16_t* in_vector2, + size_t vector_length, + int16_t right_shifts); +void WebRtcSpl_AddAffineVectorToVector(int16_t* out_vector, + int16_t* in_vector, + int16_t gain, + int32_t add_constant, + int16_t right_shifts, + size_t vector_length); +void WebRtcSpl_AffineTransformVector(int16_t* out_vector, + int16_t* in_vector, + int16_t gain, + int32_t add_constant, + int16_t right_shifts, + size_t vector_length); +// End: iLBC specific functions. + +// Signal processing operations. + +// A 32-bit fix-point implementation of auto-correlation computation +// +// Input: +// - in_vector : Vector to calculate autocorrelation upon +// - in_vector_length : Length (in samples) of |vector| +// - order : The order up to which the autocorrelation should be +// calculated +// +// Output: +// - result : auto-correlation values (values should be seen +// relative to each other since the absolute values +// might have been down shifted to avoid overflow) +// +// - scale : The number of left shifts required to obtain the +// auto-correlation in Q0 +// +// Return value : Number of samples in |result|, i.e. (order+1) +size_t WebRtcSpl_AutoCorrelation(const int16_t* in_vector, + size_t in_vector_length, + size_t order, + int32_t* result, + int* scale); + +// A 32-bit fix-point implementation of the Levinson-Durbin algorithm that +// does NOT use the 64 bit class +// +// Input: +// - auto_corr : Vector with autocorrelation values of length >= |order|+1 +// - order : The LPC filter order (support up to order 20) +// +// Output: +// - lpc_coef : lpc_coef[0..order] LPC coefficients in Q12 +// - refl_coef : refl_coef[0...order-1]| Reflection coefficients in Q15 +// +// Return value : 1 for stable 0 for unstable +int16_t WebRtcSpl_LevinsonDurbin(const int32_t* auto_corr, + int16_t* lpc_coef, + int16_t* refl_coef, + size_t order); + +// Converts reflection coefficients |refl_coef| to LPC coefficients |lpc_coef|. +// This version is a 16 bit operation. +// +// NOTE: The 16 bit refl_coef -> lpc_coef conversion might result in a +// "slightly unstable" filter (i.e., a pole just outside the unit circle) in +// "rare" cases even if the reflection coefficients are stable. +// +// Input: +// - refl_coef : Reflection coefficients in Q15 that should be converted +// to LPC coefficients +// - use_order : Number of coefficients in |refl_coef| +// +// Output: +// - lpc_coef : LPC coefficients in Q12 +void WebRtcSpl_ReflCoefToLpc(const int16_t* refl_coef, + int use_order, + int16_t* lpc_coef); + +// Converts LPC coefficients |lpc_coef| to reflection coefficients |refl_coef|. +// This version is a 16 bit operation. +// The conversion is implemented by the step-down algorithm. +// +// Input: +// - lpc_coef : LPC coefficients in Q12, that should be converted to +// reflection coefficients +// - use_order : Number of coefficients in |lpc_coef| +// +// Output: +// - refl_coef : Reflection coefficients in Q15. +void WebRtcSpl_LpcToReflCoef(int16_t* lpc_coef, + int use_order, + int16_t* refl_coef); + +// Calculates reflection coefficients (16 bit) from auto-correlation values +// +// Input: +// - auto_corr : Auto-correlation values +// - use_order : Number of coefficients wanted be calculated +// +// Output: +// - refl_coef : Reflection coefficients in Q15. +void WebRtcSpl_AutoCorrToReflCoef(const int32_t* auto_corr, + int use_order, + int16_t* refl_coef); + +// The functions (with related pointer) calculate the cross-correlation between +// two sequences |seq1| and |seq2|. +// |seq1| is fixed and |seq2| slides as the pointer is increased with the +// amount |step_seq2|. Note the arguments should obey the relationship: +// |dim_seq| - 1 + |step_seq2| * (|dim_cross_correlation| - 1) < +// buffer size of |seq2| +// +// Input: +// - seq1 : First sequence (fixed throughout the correlation) +// - seq2 : Second sequence (slides |step_vector2| for each +// new correlation) +// - dim_seq : Number of samples to use in the cross-correlation +// - dim_cross_correlation : Number of cross-correlations to calculate (the +// start position for |vector2| is updated for each +// new one) +// - right_shifts : Number of right bit shifts to use. This will +// become the output Q-domain. +// - step_seq2 : How many (positive or negative) steps the +// |vector2| pointer should be updated for each new +// cross-correlation value. +// +// Output: +// - cross_correlation : The cross-correlation in Q(-right_shifts) +typedef void (*CrossCorrelation)(int32_t* cross_correlation, + const int16_t* seq1, + const int16_t* seq2, + size_t dim_seq, + size_t dim_cross_correlation, + int right_shifts, + int step_seq2); +extern CrossCorrelation WebRtcSpl_CrossCorrelation; +void WebRtcSpl_CrossCorrelationC(int32_t* cross_correlation, + const int16_t* seq1, + const int16_t* seq2, + size_t dim_seq, + size_t dim_cross_correlation, + int right_shifts, + int step_seq2); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +void WebRtcSpl_CrossCorrelationNeon(int32_t* cross_correlation, + const int16_t* seq1, + const int16_t* seq2, + size_t dim_seq, + size_t dim_cross_correlation, + int right_shifts, + int step_seq2); +#endif +#if defined(MIPS32_LE) +void WebRtcSpl_CrossCorrelation_mips(int32_t* cross_correlation, + const int16_t* seq1, + const int16_t* seq2, + size_t dim_seq, + size_t dim_cross_correlation, + int right_shifts, + int step_seq2); +#endif + +// Creates (the first half of) a Hanning window. Size must be at least 1 and +// at most 512. +// +// Input: +// - size : Length of the requested Hanning window (1 to 512) +// +// Output: +// - window : Hanning vector in Q14. +void WebRtcSpl_GetHanningWindow(int16_t* window, size_t size); + +// Calculates y[k] = sqrt(1 - x[k]^2) for each element of the input vector +// |in_vector|. Input and output values are in Q15. +// +// Inputs: +// - in_vector : Values to calculate sqrt(1 - x^2) of +// - vector_length : Length of vector |in_vector| +// +// Output: +// - out_vector : Output values in Q15 +void WebRtcSpl_SqrtOfOneMinusXSquared(int16_t* in_vector, + size_t vector_length, + int16_t* out_vector); +// End: Signal processing operations. + +// Randomization functions. Implementations collected in +// randomization_functions.c and descriptions at bottom of this file. +int16_t WebRtcSpl_RandU(uint32_t* seed); +int16_t WebRtcSpl_RandN(uint32_t* seed); +int16_t WebRtcSpl_RandUArray(int16_t* vector, + int16_t vector_length, + uint32_t* seed); +// End: Randomization functions. + +// Math functions +int32_t WebRtcSpl_Sqrt(int32_t value); +int32_t WebRtcSpl_SqrtFloor(int32_t value); + +// Divisions. Implementations collected in division_operations.c and +// descriptions at bottom of this file. +uint32_t WebRtcSpl_DivU32U16(uint32_t num, uint16_t den); +int32_t WebRtcSpl_DivW32W16(int32_t num, int16_t den); +int16_t WebRtcSpl_DivW32W16ResW16(int32_t num, int16_t den); +int32_t WebRtcSpl_DivResultInQ31(int32_t num, int32_t den); +int32_t WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low); +// End: Divisions. + +int32_t WebRtcSpl_Energy(int16_t* vector, + size_t vector_length, + int* scale_factor); + +// Calculates the dot product between two (int16_t) vectors. +// +// Input: +// - vector1 : Vector 1 +// - vector2 : Vector 2 +// - vector_length : Number of samples used in the dot product +// - scaling : The number of right bit shifts to apply on each term +// during calculation to avoid overflow, i.e., the +// output will be in Q(-|scaling|) +// +// Return value : The dot product in Q(-scaling) +int32_t WebRtcSpl_DotProductWithScale(const int16_t* vector1, + const int16_t* vector2, + size_t length, + int scaling); + +// Filter operations. +size_t WebRtcSpl_FilterAR(const int16_t* ar_coef, + size_t ar_coef_length, + const int16_t* in_vector, + size_t in_vector_length, + int16_t* filter_state, + size_t filter_state_length, + int16_t* filter_state_low, + size_t filter_state_low_length, + int16_t* out_vector, + int16_t* out_vector_low, + size_t out_vector_low_length); + +// WebRtcSpl_FilterMAFastQ12(...) +// +// Performs a MA filtering on a vector in Q12 +// +// Input: +// - in_vector : Input samples (state in positions +// in_vector[-order] .. in_vector[-1]) +// - ma_coef : Filter coefficients (in Q12) +// - ma_coef_length : Number of B coefficients (order+1) +// - vector_length : Number of samples to be filtered +// +// Output: +// - out_vector : Filtered samples +// +void WebRtcSpl_FilterMAFastQ12(const int16_t* in_vector, + int16_t* out_vector, + const int16_t* ma_coef, + size_t ma_coef_length, + size_t vector_length); + +// Performs a AR filtering on a vector in Q12 +// Input: +// - data_in : Input samples +// - data_out : State information in positions +// data_out[-order] .. data_out[-1] +// - coefficients : Filter coefficients (in Q12) +// - coefficients_length: Number of coefficients (order+1) +// - data_length : Number of samples to be filtered +// Output: +// - data_out : Filtered samples +void WebRtcSpl_FilterARFastQ12(const int16_t* data_in, + int16_t* data_out, + const int16_t* __restrict coefficients, + size_t coefficients_length, + size_t data_length); + +// The functions (with related pointer) perform a MA down sampling filter +// on a vector. +// Input: +// - data_in : Input samples (state in positions +// data_in[-order] .. data_in[-1]) +// - data_in_length : Number of samples in |data_in| to be filtered. +// This must be at least +// |delay| + |factor|*(|out_vector_length|-1) + 1) +// - data_out_length : Number of down sampled samples desired +// - coefficients : Filter coefficients (in Q12) +// - coefficients_length: Number of coefficients (order+1) +// - factor : Decimation factor +// - delay : Delay of filter (compensated for in out_vector) +// Output: +// - data_out : Filtered samples +// Return value : 0 if OK, -1 if |in_vector| is too short +typedef int (*DownsampleFast)(const int16_t* data_in, + size_t data_in_length, + int16_t* data_out, + size_t data_out_length, + const int16_t* __restrict coefficients, + size_t coefficients_length, + int factor, + size_t delay); +extern DownsampleFast WebRtcSpl_DownsampleFast; +int WebRtcSpl_DownsampleFastC(const int16_t* data_in, + size_t data_in_length, + int16_t* data_out, + size_t data_out_length, + const int16_t* __restrict coefficients, + size_t coefficients_length, + int factor, + size_t delay); +#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) +int WebRtcSpl_DownsampleFastNeon(const int16_t* data_in, + size_t data_in_length, + int16_t* data_out, + size_t data_out_length, + const int16_t* __restrict coefficients, + size_t coefficients_length, + int factor, + size_t delay); +#endif +#if defined(MIPS32_LE) +int WebRtcSpl_DownsampleFast_mips(const int16_t* data_in, + size_t data_in_length, + int16_t* data_out, + size_t data_out_length, + const int16_t* __restrict coefficients, + size_t coefficients_length, + int factor, + size_t delay); +#endif + +// End: Filter operations. + +// FFT operations + +int WebRtcSpl_ComplexFFT(int16_t vector[], int stages, int mode); +int WebRtcSpl_ComplexIFFT(int16_t vector[], int stages, int mode); + +// Treat a 16-bit complex data buffer |complex_data| as an array of 32-bit +// values, and swap elements whose indexes are bit-reverses of each other. +// +// Input: +// - complex_data : Complex data buffer containing 2^|stages| real +// elements interleaved with 2^|stages| imaginary +// elements: [Re Im Re Im Re Im....] +// - stages : Number of FFT stages. Must be at least 3 and at most +// 10, since the table WebRtcSpl_kSinTable1024[] is 1024 +// elements long. +// +// Output: +// - complex_data : The complex data buffer. + +void WebRtcSpl_ComplexBitReverse(int16_t* __restrict complex_data, int stages); + +// End: FFT operations + +/************************************************************ + * + * RESAMPLING FUNCTIONS AND THEIR STRUCTS ARE DEFINED BELOW + * + ************************************************************/ + +/******************************************************************* + * resample.c + * + * Includes the following resampling combinations + * 22 kHz -> 16 kHz + * 16 kHz -> 22 kHz + * 22 kHz -> 8 kHz + * 8 kHz -> 22 kHz + * + ******************************************************************/ + +// state structure for 22 -> 16 resampler +typedef struct { + int32_t S_22_44[8]; + int32_t S_44_32[8]; + int32_t S_32_16[8]; +} WebRtcSpl_State22khzTo16khz; + +void WebRtcSpl_Resample22khzTo16khz(const int16_t* in, + int16_t* out, + WebRtcSpl_State22khzTo16khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample22khzTo16khz(WebRtcSpl_State22khzTo16khz* state); + +// state structure for 16 -> 22 resampler +typedef struct { + int32_t S_16_32[8]; + int32_t S_32_22[8]; +} WebRtcSpl_State16khzTo22khz; + +void WebRtcSpl_Resample16khzTo22khz(const int16_t* in, + int16_t* out, + WebRtcSpl_State16khzTo22khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample16khzTo22khz(WebRtcSpl_State16khzTo22khz* state); + +// state structure for 22 -> 8 resampler +typedef struct { + int32_t S_22_22[16]; + int32_t S_22_16[8]; + int32_t S_16_8[8]; +} WebRtcSpl_State22khzTo8khz; + +void WebRtcSpl_Resample22khzTo8khz(const int16_t* in, int16_t* out, + WebRtcSpl_State22khzTo8khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample22khzTo8khz(WebRtcSpl_State22khzTo8khz* state); + +// state structure for 8 -> 22 resampler +typedef struct { + int32_t S_8_16[8]; + int32_t S_16_11[8]; + int32_t S_11_22[8]; +} WebRtcSpl_State8khzTo22khz; + +void WebRtcSpl_Resample8khzTo22khz(const int16_t* in, int16_t* out, + WebRtcSpl_State8khzTo22khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample8khzTo22khz(WebRtcSpl_State8khzTo22khz* state); + +/******************************************************************* + * resample_fractional.c + * Functions for internal use in the other resample functions + * + * Includes the following resampling combinations + * 48 kHz -> 32 kHz + * 32 kHz -> 24 kHz + * 44 kHz -> 32 kHz + * + ******************************************************************/ + +void WebRtcSpl_Resample48khzTo32khz(const int32_t* In, int32_t* Out, size_t K); + +void WebRtcSpl_Resample32khzTo24khz(const int32_t* In, int32_t* Out, size_t K); + +void WebRtcSpl_Resample44khzTo32khz(const int32_t* In, int32_t* Out, size_t K); + +/******************************************************************* + * resample_48khz.c + * + * Includes the following resampling combinations + * 48 kHz -> 16 kHz + * 16 kHz -> 48 kHz + * 48 kHz -> 8 kHz + * 8 kHz -> 48 kHz + * + ******************************************************************/ + +typedef struct { + int32_t S_48_48[16]; + int32_t S_48_32[8]; + int32_t S_32_16[8]; +} WebRtcSpl_State48khzTo16khz; + +void WebRtcSpl_Resample48khzTo16khz(const int16_t* in, int16_t* out, + WebRtcSpl_State48khzTo16khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample48khzTo16khz(WebRtcSpl_State48khzTo16khz* state); + +typedef struct { + int32_t S_16_32[8]; + int32_t S_32_24[8]; + int32_t S_24_48[8]; +} WebRtcSpl_State16khzTo48khz; + +void WebRtcSpl_Resample16khzTo48khz(const int16_t* in, int16_t* out, + WebRtcSpl_State16khzTo48khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample16khzTo48khz(WebRtcSpl_State16khzTo48khz* state); + +typedef struct { + int32_t S_48_24[8]; + int32_t S_24_24[16]; + int32_t S_24_16[8]; + int32_t S_16_8[8]; +} WebRtcSpl_State48khzTo8khz; + +void WebRtcSpl_Resample48khzTo8khz(const int16_t* in, int16_t* out, + WebRtcSpl_State48khzTo8khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample48khzTo8khz(WebRtcSpl_State48khzTo8khz* state); + +typedef struct { + int32_t S_8_16[8]; + int32_t S_16_12[8]; + int32_t S_12_24[8]; + int32_t S_24_48[8]; +} WebRtcSpl_State8khzTo48khz; + +void WebRtcSpl_Resample8khzTo48khz(const int16_t* in, int16_t* out, + WebRtcSpl_State8khzTo48khz* state, + int32_t* tmpmem); + +void WebRtcSpl_ResetResample8khzTo48khz(WebRtcSpl_State8khzTo48khz* state); + +/******************************************************************* + * resample_by_2.c + * + * Includes down and up sampling by a factor of two. + * + ******************************************************************/ + +void WebRtcSpl_DownsampleBy2(const int16_t* in, size_t len, + int16_t* out, int32_t* filtState); + +void WebRtcSpl_UpsampleBy2(const int16_t* in, size_t len, + int16_t* out, int32_t* filtState); + +/************************************************************ + * END OF RESAMPLING FUNCTIONS + ************************************************************/ +void WebRtcSpl_AnalysisQMF(const int16_t* in_data, + size_t in_data_length, + int16_t* low_band, + int16_t* high_band, + int32_t* filter_state1, + int32_t* filter_state2); +void WebRtcSpl_SynthesisQMF(const int16_t* low_band, + const int16_t* high_band, + size_t band_length, + int16_t* out_data, + int32_t* filter_state1, + int32_t* filter_state2); + +#ifdef __cplusplus +} +#endif // __cplusplus +#endif // WEBRTC_SPL_SIGNAL_PROCESSING_LIBRARY_H_ + +// +// WebRtcSpl_AddSatW16(...) +// WebRtcSpl_AddSatW32(...) +// +// Returns the result of a saturated 16-bit, respectively 32-bit, addition of +// the numbers specified by the |var1| and |var2| parameters. +// +// Input: +// - var1 : Input variable 1 +// - var2 : Input variable 2 +// +// Return value : Added and saturated value +// + +// +// WebRtcSpl_SubSatW16(...) +// WebRtcSpl_SubSatW32(...) +// +// Returns the result of a saturated 16-bit, respectively 32-bit, subtraction +// of the numbers specified by the |var1| and |var2| parameters. +// +// Input: +// - var1 : Input variable 1 +// - var2 : Input variable 2 +// +// Returned value : Subtracted and saturated value +// + +// +// WebRtcSpl_GetSizeInBits(...) +// +// Returns the # of bits that are needed at the most to represent the number +// specified by the |value| parameter. +// +// Input: +// - value : Input value +// +// Return value : Number of bits needed to represent |value| +// + +// +// WebRtcSpl_NormW32(...) +// +// Norm returns the # of left shifts required to 32-bit normalize the 32-bit +// signed number specified by the |value| parameter. +// +// Input: +// - value : Input value +// +// Return value : Number of bit shifts needed to 32-bit normalize |value| +// + +// +// WebRtcSpl_NormW16(...) +// +// Norm returns the # of left shifts required to 16-bit normalize the 16-bit +// signed number specified by the |value| parameter. +// +// Input: +// - value : Input value +// +// Return value : Number of bit shifts needed to 32-bit normalize |value| +// + +// +// WebRtcSpl_NormU32(...) +// +// Norm returns the # of left shifts required to 32-bit normalize the unsigned +// 32-bit number specified by the |value| parameter. +// +// Input: +// - value : Input value +// +// Return value : Number of bit shifts needed to 32-bit normalize |value| +// + +// +// WebRtcSpl_GetScalingSquare(...) +// +// Returns the # of bits required to scale the samples specified in the +// |in_vector| parameter so that, if the squares of the samples are added the +// # of times specified by the |times| parameter, the 32-bit addition will not +// overflow (result in int32_t). +// +// Input: +// - in_vector : Input vector to check scaling on +// - in_vector_length : Samples in |in_vector| +// - times : Number of additions to be performed +// +// Return value : Number of right bit shifts needed to avoid +// overflow in the addition calculation +// + +// +// WebRtcSpl_MemSetW16(...) +// +// Sets all the values in the int16_t vector |vector| of length +// |vector_length| to the specified value |set_value| +// +// Input: +// - vector : Pointer to the int16_t vector +// - set_value : Value specified +// - vector_length : Length of vector +// + +// +// WebRtcSpl_MemSetW32(...) +// +// Sets all the values in the int32_t vector |vector| of length +// |vector_length| to the specified value |set_value| +// +// Input: +// - vector : Pointer to the int16_t vector +// - set_value : Value specified +// - vector_length : Length of vector +// + +// +// WebRtcSpl_MemCpyReversedOrder(...) +// +// Copies all the values from the source int16_t vector |in_vector| to a +// destination int16_t vector |out_vector|. It is done in reversed order, +// meaning that the first sample of |in_vector| is copied to the last sample of +// the |out_vector|. The procedure continues until the last sample of +// |in_vector| has been copied to the first sample of |out_vector|. This +// creates a reversed vector. Used in e.g. prediction in iLBC. +// +// Input: +// - in_vector : Pointer to the first sample in a int16_t vector +// of length |length| +// - vector_length : Number of elements to copy +// +// Output: +// - out_vector : Pointer to the last sample in a int16_t vector +// of length |length| +// + +// +// WebRtcSpl_CopyFromEndW16(...) +// +// Copies the rightmost |samples| of |in_vector| (of length |in_vector_length|) +// to the vector |out_vector|. +// +// Input: +// - in_vector : Input vector +// - in_vector_length : Number of samples in |in_vector| +// - samples : Number of samples to extract (from right side) +// from |in_vector| +// +// Output: +// - out_vector : Vector with the requested samples +// + +// +// WebRtcSpl_ZerosArrayW16(...) +// WebRtcSpl_ZerosArrayW32(...) +// +// Inserts the value "zero" in all positions of a w16 and a w32 vector +// respectively. +// +// Input: +// - vector_length : Number of samples in vector +// +// Output: +// - vector : Vector containing all zeros +// + +// +// WebRtcSpl_VectorBitShiftW16(...) +// WebRtcSpl_VectorBitShiftW32(...) +// +// Bit shifts all the values in a vector up or downwards. Different calls for +// int16_t and int32_t vectors respectively. +// +// Input: +// - vector_length : Length of vector +// - in_vector : Pointer to the vector that should be bit shifted +// - right_shifts : Number of right bit shifts (negative value gives left +// shifts) +// +// Output: +// - out_vector : Pointer to the result vector (can be the same as +// |in_vector|) +// + +// +// WebRtcSpl_VectorBitShiftW32ToW16(...) +// +// Bit shifts all the values in a int32_t vector up or downwards and +// stores the result as an int16_t vector. The function will saturate the +// signal if needed, before storing in the output vector. +// +// Input: +// - vector_length : Length of vector +// - in_vector : Pointer to the vector that should be bit shifted +// - right_shifts : Number of right bit shifts (negative value gives left +// shifts) +// +// Output: +// - out_vector : Pointer to the result vector (can be the same as +// |in_vector|) +// + +// +// WebRtcSpl_ScaleVector(...) +// +// Performs the vector operation: +// out_vector[k] = (gain*in_vector[k])>>right_shifts +// +// Input: +// - in_vector : Input vector +// - gain : Scaling gain +// - vector_length : Elements in the |in_vector| +// - right_shifts : Number of right bit shifts applied +// +// Output: +// - out_vector : Output vector (can be the same as |in_vector|) +// + +// +// WebRtcSpl_ScaleVectorWithSat(...) +// +// Performs the vector operation: +// out_vector[k] = SATURATE( (gain*in_vector[k])>>right_shifts ) +// +// Input: +// - in_vector : Input vector +// - gain : Scaling gain +// - vector_length : Elements in the |in_vector| +// - right_shifts : Number of right bit shifts applied +// +// Output: +// - out_vector : Output vector (can be the same as |in_vector|) +// + +// +// WebRtcSpl_ScaleAndAddVectors(...) +// +// Performs the vector operation: +// out_vector[k] = (gain1*in_vector1[k])>>right_shifts1 +// + (gain2*in_vector2[k])>>right_shifts2 +// +// Input: +// - in_vector1 : Input vector 1 +// - gain1 : Gain to be used for vector 1 +// - right_shifts1 : Right bit shift to be used for vector 1 +// - in_vector2 : Input vector 2 +// - gain2 : Gain to be used for vector 2 +// - right_shifts2 : Right bit shift to be used for vector 2 +// - vector_length : Elements in the input vectors +// +// Output: +// - out_vector : Output vector +// + +// +// WebRtcSpl_ReverseOrderMultArrayElements(...) +// +// Performs the vector operation: +// out_vector[n] = (in_vector[n]*window[-n])>>right_shifts +// +// Input: +// - in_vector : Input vector +// - window : Window vector (should be reversed). The pointer +// should be set to the last value in the vector +// - right_shifts : Number of right bit shift to be applied after the +// multiplication +// - vector_length : Number of elements in |in_vector| +// +// Output: +// - out_vector : Output vector (can be same as |in_vector|) +// + +// +// WebRtcSpl_ElementwiseVectorMult(...) +// +// Performs the vector operation: +// out_vector[n] = (in_vector[n]*window[n])>>right_shifts +// +// Input: +// - in_vector : Input vector +// - window : Window vector. +// - right_shifts : Number of right bit shift to be applied after the +// multiplication +// - vector_length : Number of elements in |in_vector| +// +// Output: +// - out_vector : Output vector (can be same as |in_vector|) +// + +// +// WebRtcSpl_AddVectorsAndShift(...) +// +// Performs the vector operation: +// out_vector[k] = (in_vector1[k] + in_vector2[k])>>right_shifts +// +// Input: +// - in_vector1 : Input vector 1 +// - in_vector2 : Input vector 2 +// - right_shifts : Number of right bit shift to be applied after the +// multiplication +// - vector_length : Number of elements in |in_vector1| and |in_vector2| +// +// Output: +// - out_vector : Output vector (can be same as |in_vector1|) +// + +// +// WebRtcSpl_AddAffineVectorToVector(...) +// +// Adds an affine transformed vector to another vector |out_vector|, i.e, +// performs +// out_vector[k] += (in_vector[k]*gain+add_constant)>>right_shifts +// +// Input: +// - in_vector : Input vector +// - gain : Gain value, used to multiply the in vector with +// - add_constant : Constant value to add (usually 1<<(right_shifts-1), +// but others can be used as well +// - right_shifts : Number of right bit shifts (0-16) +// - vector_length : Number of samples in |in_vector| and |out_vector| +// +// Output: +// - out_vector : Vector with the output +// + +// +// WebRtcSpl_AffineTransformVector(...) +// +// Affine transforms a vector, i.e, performs +// out_vector[k] = (in_vector[k]*gain+add_constant)>>right_shifts +// +// Input: +// - in_vector : Input vector +// - gain : Gain value, used to multiply the in vector with +// - add_constant : Constant value to add (usually 1<<(right_shifts-1), +// but others can be used as well +// - right_shifts : Number of right bit shifts (0-16) +// - vector_length : Number of samples in |in_vector| and |out_vector| +// +// Output: +// - out_vector : Vector with the output +// + +// +// WebRtcSpl_IncreaseSeed(...) +// +// Increases the seed (and returns the new value) +// +// Input: +// - seed : Seed for random calculation +// +// Output: +// - seed : Updated seed value +// +// Return value : The new seed value +// + +// +// WebRtcSpl_RandU(...) +// +// Produces a uniformly distributed value in the int16_t range +// +// Input: +// - seed : Seed for random calculation +// +// Output: +// - seed : Updated seed value +// +// Return value : Uniformly distributed value in the range +// [Word16_MIN...Word16_MAX] +// + +// +// WebRtcSpl_RandN(...) +// +// Produces a normal distributed value in the int16_t range +// +// Input: +// - seed : Seed for random calculation +// +// Output: +// - seed : Updated seed value +// +// Return value : N(0,1) value in the Q13 domain +// + +// +// WebRtcSpl_RandUArray(...) +// +// Produces a uniformly distributed vector with elements in the int16_t +// range +// +// Input: +// - vector_length : Samples wanted in the vector +// - seed : Seed for random calculation +// +// Output: +// - vector : Vector with the uniform values +// - seed : Updated seed value +// +// Return value : Number of samples in vector, i.e., |vector_length| +// + +// +// WebRtcSpl_Sqrt(...) +// +// Returns the square root of the input value |value|. The precision of this +// function is integer precision, i.e., sqrt(8) gives 2 as answer. +// If |value| is a negative number then 0 is returned. +// +// Algorithm: +// +// A sixth order Taylor Series expansion is used here to compute the square +// root of a number y^0.5 = (1+x)^0.5 +// where +// x = y-1 +// = 1+(x/2)-0.5*((x/2)^2+0.5*((x/2)^3-0.625*((x/2)^4+0.875*((x/2)^5) +// 0.5 <= x < 1 +// +// Input: +// - value : Value to calculate sqrt of +// +// Return value : Result of the sqrt calculation +// + +// +// WebRtcSpl_SqrtFloor(...) +// +// Returns the square root of the input value |value|. The precision of this +// function is rounding down integer precision, i.e., sqrt(8) gives 2 as answer. +// If |value| is a negative number then 0 is returned. +// +// Algorithm: +// +// An iterative 4 cylce/bit routine +// +// Input: +// - value : Value to calculate sqrt of +// +// Return value : Result of the sqrt calculation +// + +// +// WebRtcSpl_DivU32U16(...) +// +// Divides a uint32_t |num| by a uint16_t |den|. +// +// If |den|==0, (uint32_t)0xFFFFFFFF is returned. +// +// Input: +// - num : Numerator +// - den : Denominator +// +// Return value : Result of the division (as a uint32_t), i.e., the +// integer part of num/den. +// + +// +// WebRtcSpl_DivW32W16(...) +// +// Divides a int32_t |num| by a int16_t |den|. +// +// If |den|==0, (int32_t)0x7FFFFFFF is returned. +// +// Input: +// - num : Numerator +// - den : Denominator +// +// Return value : Result of the division (as a int32_t), i.e., the +// integer part of num/den. +// + +// +// WebRtcSpl_DivW32W16ResW16(...) +// +// Divides a int32_t |num| by a int16_t |den|, assuming that the +// result is less than 32768, otherwise an unpredictable result will occur. +// +// If |den|==0, (int16_t)0x7FFF is returned. +// +// Input: +// - num : Numerator +// - den : Denominator +// +// Return value : Result of the division (as a int16_t), i.e., the +// integer part of num/den. +// + +// +// WebRtcSpl_DivResultInQ31(...) +// +// Divides a int32_t |num| by a int16_t |den|, assuming that the +// absolute value of the denominator is larger than the numerator, otherwise +// an unpredictable result will occur. +// +// Input: +// - num : Numerator +// - den : Denominator +// +// Return value : Result of the division in Q31. +// + +// +// WebRtcSpl_DivW32HiLow(...) +// +// Divides a int32_t |num| by a denominator in hi, low format. The +// absolute value of the denominator has to be larger (or equal to) the +// numerator. +// +// Input: +// - num : Numerator +// - den_hi : High part of denominator +// - den_low : Low part of denominator +// +// Return value : Divided value in Q31 +// + +// +// WebRtcSpl_Energy(...) +// +// Calculates the energy of a vector +// +// Input: +// - vector : Vector which the energy should be calculated on +// - vector_length : Number of samples in vector +// +// Output: +// - scale_factor : Number of left bit shifts needed to get the physical +// energy value, i.e, to get the Q0 value +// +// Return value : Energy value in Q(-|scale_factor|) +// + +// +// WebRtcSpl_FilterAR(...) +// +// Performs a 32-bit AR filtering on a vector in Q12 +// +// Input: +// - ar_coef : AR-coefficient vector (values in Q12), +// ar_coef[0] must be 4096. +// - ar_coef_length : Number of coefficients in |ar_coef|. +// - in_vector : Vector to be filtered. +// - in_vector_length : Number of samples in |in_vector|. +// - filter_state : Current state (higher part) of the filter. +// - filter_state_length : Length (in samples) of |filter_state|. +// - filter_state_low : Current state (lower part) of the filter. +// - filter_state_low_length : Length (in samples) of |filter_state_low|. +// - out_vector_low_length : Maximum length (in samples) of +// |out_vector_low|. +// +// Output: +// - filter_state : Updated state (upper part) vector. +// - filter_state_low : Updated state (lower part) vector. +// - out_vector : Vector containing the upper part of the +// filtered values. +// - out_vector_low : Vector containing the lower part of the +// filtered values. +// +// Return value : Number of samples in the |out_vector|. +// + +// +// WebRtcSpl_ComplexIFFT(...) +// +// Complex Inverse FFT +// +// Computes an inverse complex 2^|stages|-point FFT on the input vector, which +// is in bit-reversed order. The original content of the vector is destroyed in +// the process, since the input is overwritten by the output, normal-ordered, +// FFT vector. With X as the input complex vector, y as the output complex +// vector and with M = 2^|stages|, the following is computed: +// +// M-1 +// y(k) = sum[X(i)*[cos(2*pi*i*k/M) + j*sin(2*pi*i*k/M)]] +// i=0 +// +// The implementations are optimized for speed, not for code size. It uses the +// decimation-in-time algorithm with radix-2 butterfly technique. +// +// Input: +// - vector : In pointer to complex vector containing 2^|stages| +// real elements interleaved with 2^|stages| imaginary +// elements. +// [ReImReImReIm....] +// The elements are in Q(-scale) domain, see more on Return +// Value below. +// +// - stages : Number of FFT stages. Must be at least 3 and at most 10, +// since the table WebRtcSpl_kSinTable1024[] is 1024 +// elements long. +// +// - mode : This parameter gives the user to choose how the FFT +// should work. +// mode==0: Low-complexity and Low-accuracy mode +// mode==1: High-complexity and High-accuracy mode +// +// Output: +// - vector : Out pointer to the FFT vector (the same as input). +// +// Return Value : The scale value that tells the number of left bit shifts +// that the elements in the |vector| should be shifted with +// in order to get Q0 values, i.e. the physically correct +// values. The scale parameter is always 0 or positive, +// except if N>1024 (|stages|>10), which returns a scale +// value of -1, indicating error. +// + +// +// WebRtcSpl_ComplexFFT(...) +// +// Complex FFT +// +// Computes a complex 2^|stages|-point FFT on the input vector, which is in +// bit-reversed order. The original content of the vector is destroyed in +// the process, since the input is overwritten by the output, normal-ordered, +// FFT vector. With x as the input complex vector, Y as the output complex +// vector and with M = 2^|stages|, the following is computed: +// +// M-1 +// Y(k) = 1/M * sum[x(i)*[cos(2*pi*i*k/M) + j*sin(2*pi*i*k/M)]] +// i=0 +// +// The implementations are optimized for speed, not for code size. It uses the +// decimation-in-time algorithm with radix-2 butterfly technique. +// +// This routine prevents overflow by scaling by 2 before each FFT stage. This is +// a fixed scaling, for proper normalization - there will be log2(n) passes, so +// this results in an overall factor of 1/n, distributed to maximize arithmetic +// accuracy. +// +// Input: +// - vector : In pointer to complex vector containing 2^|stages| real +// elements interleaved with 2^|stages| imaginary elements. +// [ReImReImReIm....] +// The output is in the Q0 domain. +// +// - stages : Number of FFT stages. Must be at least 3 and at most 10, +// since the table WebRtcSpl_kSinTable1024[] is 1024 +// elements long. +// +// - mode : This parameter gives the user to choose how the FFT +// should work. +// mode==0: Low-complexity and Low-accuracy mode +// mode==1: High-complexity and High-accuracy mode +// +// Output: +// - vector : The output FFT vector is in the Q0 domain. +// +// Return value : The scale parameter is always 0, except if N>1024, +// which returns a scale value of -1, indicating error. +// + +// +// WebRtcSpl_AnalysisQMF(...) +// +// Splits a 0-2*F Hz signal into two sub bands: 0-F Hz and F-2*F Hz. The +// current version has F = 8000, therefore, a super-wideband audio signal is +// split to lower-band 0-8 kHz and upper-band 8-16 kHz. +// +// Input: +// - in_data : Wide band speech signal, 320 samples (10 ms) +// +// Input & Output: +// - filter_state1 : Filter state for first All-pass filter +// - filter_state2 : Filter state for second All-pass filter +// +// Output: +// - low_band : Lower-band signal 0-8 kHz band, 160 samples (10 ms) +// - high_band : Upper-band signal 8-16 kHz band (flipped in frequency +// domain), 160 samples (10 ms) +// + +// +// WebRtcSpl_SynthesisQMF(...) +// +// Combines the two sub bands (0-F and F-2*F Hz) into a signal of 0-2*F +// Hz, (current version has F = 8000 Hz). So the filter combines lower-band +// (0-8 kHz) and upper-band (8-16 kHz) channels to obtain super-wideband 0-16 +// kHz audio. +// +// Input: +// - low_band : The signal with the 0-8 kHz band, 160 samples (10 ms) +// - high_band : The signal with the 8-16 kHz band, 160 samples (10 ms) +// +// Input & Output: +// - filter_state1 : Filter state for first All-pass filter +// - filter_state2 : Filter state for second All-pass filter +// +// Output: +// - out_data : Super-wideband speech signal, 0-16 kHz +// + +// int16_t WebRtcSpl_SatW32ToW16(...) +// +// This function saturates a 32-bit word into a 16-bit word. +// +// Input: +// - value32 : The value of a 32-bit word. +// +// Output: +// - out16 : the saturated 16-bit word. +// + +// int32_t WebRtc_MulAccumW16(...) +// +// This function multiply a 16-bit word by a 16-bit word, and accumulate this +// value to a 32-bit integer. +// +// Input: +// - a : The value of the first 16-bit word. +// - b : The value of the second 16-bit word. +// - c : The value of an 32-bit integer. +// +// Return Value: The value of a * b + c. +// |