1/* 2 * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 12/* 13 * This header file includes all of the fix point signal processing library (SPL) function 14 * descriptions and declarations. 15 * For specific function calls, see bottom of file. 16 */ 17 18#ifndef WEBRTC_SPL_SIGNAL_PROCESSING_LIBRARY_H_ 19#define WEBRTC_SPL_SIGNAL_PROCESSING_LIBRARY_H_ 20 21#include <string.h> 22#include "webrtc/typedefs.h" 23 24// Macros specific for the fixed point implementation 25#define WEBRTC_SPL_WORD16_MAX 32767 26#define WEBRTC_SPL_WORD16_MIN -32768 27#define WEBRTC_SPL_WORD32_MAX (int32_t)0x7fffffff 28#define WEBRTC_SPL_WORD32_MIN (int32_t)0x80000000 29#define WEBRTC_SPL_MAX_LPC_ORDER 14 30#define WEBRTC_SPL_MIN(A, B) (A < B ? A : B) // Get min value 31#define WEBRTC_SPL_MAX(A, B) (A > B ? A : B) // Get max value 32// TODO(kma/bjorn): For the next two macros, investigate how to correct the code 33// for inputs of a = WEBRTC_SPL_WORD16_MIN or WEBRTC_SPL_WORD32_MIN. 34#define WEBRTC_SPL_ABS_W16(a) \ 35 (((int16_t)a >= 0) ? ((int16_t)a) : -((int16_t)a)) 36#define WEBRTC_SPL_ABS_W32(a) \ 37 (((int32_t)a >= 0) ? ((int32_t)a) : -((int32_t)a)) 38 39#define WEBRTC_SPL_MUL(a, b) \ 40 ((int32_t) ((int32_t)(a) * (int32_t)(b))) 41#define WEBRTC_SPL_UMUL(a, b) \ 42 ((uint32_t) ((uint32_t)(a) * (uint32_t)(b))) 43#define WEBRTC_SPL_UMUL_32_16(a, b) \ 44 ((uint32_t) ((uint32_t)(a) * (uint16_t)(b))) 45#define WEBRTC_SPL_MUL_16_U16(a, b) \ 46 ((int32_t)(int16_t)(a) * (uint16_t)(b)) 47 48#ifndef WEBRTC_ARCH_ARM_V7 49// For ARMv7 platforms, these are inline functions in spl_inl_armv7.h 50#ifndef MIPS32_LE 51// For MIPS platforms, these are inline functions in spl_inl_mips.h 52#define WEBRTC_SPL_MUL_16_16(a, b) \ 53 ((int32_t) (((int16_t)(a)) * ((int16_t)(b)))) 54#define WEBRTC_SPL_MUL_16_32_RSFT16(a, b) \ 55 (WEBRTC_SPL_MUL_16_16(a, b >> 16) \ 56 + ((WEBRTC_SPL_MUL_16_16(a, (b & 0xffff) >> 1) + 0x4000) >> 15)) 57#endif 58#endif 59 60#define WEBRTC_SPL_MUL_16_32_RSFT11(a, b) \ 61 ((WEBRTC_SPL_MUL_16_16(a, (b) >> 16) << 5) \ 62 + (((WEBRTC_SPL_MUL_16_U16(a, (uint16_t)(b)) >> 1) + 0x0200) >> 10)) 63#define WEBRTC_SPL_MUL_16_32_RSFT14(a, b) \ 64 ((WEBRTC_SPL_MUL_16_16(a, (b) >> 16) << 2) \ 65 + (((WEBRTC_SPL_MUL_16_U16(a, (uint16_t)(b)) >> 1) + 0x1000) >> 13)) 66#define WEBRTC_SPL_MUL_16_32_RSFT15(a, b) \ 67 ((WEBRTC_SPL_MUL_16_16(a, (b) >> 16) << 1) \ 68 + (((WEBRTC_SPL_MUL_16_U16(a, (uint16_t)(b)) >> 1) + 0x2000) >> 14)) 69 70#define WEBRTC_SPL_MUL_16_16_RSFT(a, b, c) \ 71 (WEBRTC_SPL_MUL_16_16(a, b) >> (c)) 72 73#define WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(a, b, c) \ 74 ((WEBRTC_SPL_MUL_16_16(a, b) + ((int32_t) \ 75 (((int32_t)1) << ((c) - 1)))) >> (c)) 76 77// C + the 32 most significant bits of A * B 78#define WEBRTC_SPL_SCALEDIFF32(A, B, C) \ 79 (C + (B >> 16) * A + (((uint32_t)(0x0000FFFF & B) * A) >> 16)) 80 81#define WEBRTC_SPL_SAT(a, b, c) (b > a ? a : b < c ? c : b) 82 83// Shifting with negative numbers allowed 84// Positive means left shift 85#define WEBRTC_SPL_SHIFT_W32(x, c) \ 86 (((c) >= 0) ? ((x) << (c)) : ((x) >> (-(c)))) 87 88// Shifting with negative numbers not allowed 89// We cannot do casting here due to signed/unsigned problem 90#define WEBRTC_SPL_LSHIFT_W32(x, c) ((x) << (c)) 91 92#define WEBRTC_SPL_RSHIFT_U32(x, c) ((uint32_t)(x) >> (c)) 93 94#define WEBRTC_SPL_RAND(a) \ 95 ((int16_t)((((int16_t)a * 18816) >> 7) & 0x00007fff)) 96 97#ifdef __cplusplus 98extern "C" { 99#endif 100 101#define WEBRTC_SPL_MEMCPY_W16(v1, v2, length) \ 102 memcpy(v1, v2, (length) * sizeof(int16_t)) 103 104// inline functions: 105#include "webrtc/common_audio/signal_processing/include/spl_inl.h" 106 107// Initialize SPL. Currently it contains only function pointer initialization. 108// If the underlying platform is known to be ARM-Neon (WEBRTC_HAS_NEON defined), 109// the pointers will be assigned to code optimized for Neon; otherwise 110// if run-time Neon detection (WEBRTC_DETECT_NEON) is enabled, the pointers 111// will be assigned to either Neon code or generic C code; otherwise, generic C 112// code will be assigned. 113// Note that this function MUST be called in any application that uses SPL 114// functions. 115void WebRtcSpl_Init(); 116 117int16_t WebRtcSpl_GetScalingSquare(int16_t* in_vector, 118 size_t in_vector_length, 119 size_t times); 120 121// Copy and set operations. Implementation in copy_set_operations.c. 122// Descriptions at bottom of file. 123void WebRtcSpl_MemSetW16(int16_t* vector, 124 int16_t set_value, 125 size_t vector_length); 126void WebRtcSpl_MemSetW32(int32_t* vector, 127 int32_t set_value, 128 size_t vector_length); 129void WebRtcSpl_MemCpyReversedOrder(int16_t* out_vector, 130 int16_t* in_vector, 131 size_t vector_length); 132void WebRtcSpl_CopyFromEndW16(const int16_t* in_vector, 133 size_t in_vector_length, 134 size_t samples, 135 int16_t* out_vector); 136void WebRtcSpl_ZerosArrayW16(int16_t* vector, 137 size_t vector_length); 138void WebRtcSpl_ZerosArrayW32(int32_t* vector, 139 size_t vector_length); 140// End: Copy and set operations. 141 142 143// Minimum and maximum operation functions and their pointers. 144// Implementation in min_max_operations.c. 145 146// Returns the largest absolute value in a signed 16-bit vector. 147// 148// Input: 149// - vector : 16-bit input vector. 150// - length : Number of samples in vector. 151// 152// Return value : Maximum absolute value in vector. 153typedef int16_t (*MaxAbsValueW16)(const int16_t* vector, size_t length); 154extern MaxAbsValueW16 WebRtcSpl_MaxAbsValueW16; 155int16_t WebRtcSpl_MaxAbsValueW16C(const int16_t* vector, size_t length); 156#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 157int16_t WebRtcSpl_MaxAbsValueW16Neon(const int16_t* vector, size_t length); 158#endif 159#if defined(MIPS32_LE) 160int16_t WebRtcSpl_MaxAbsValueW16_mips(const int16_t* vector, size_t length); 161#endif 162 163// Returns the largest absolute value in a signed 32-bit vector. 164// 165// Input: 166// - vector : 32-bit input vector. 167// - length : Number of samples in vector. 168// 169// Return value : Maximum absolute value in vector. 170typedef int32_t (*MaxAbsValueW32)(const int32_t* vector, size_t length); 171extern MaxAbsValueW32 WebRtcSpl_MaxAbsValueW32; 172int32_t WebRtcSpl_MaxAbsValueW32C(const int32_t* vector, size_t length); 173#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 174int32_t WebRtcSpl_MaxAbsValueW32Neon(const int32_t* vector, size_t length); 175#endif 176#if defined(MIPS_DSP_R1_LE) 177int32_t WebRtcSpl_MaxAbsValueW32_mips(const int32_t* vector, size_t length); 178#endif 179 180// Returns the maximum value of a 16-bit vector. 181// 182// Input: 183// - vector : 16-bit input vector. 184// - length : Number of samples in vector. 185// 186// Return value : Maximum sample value in |vector|. 187typedef int16_t (*MaxValueW16)(const int16_t* vector, size_t length); 188extern MaxValueW16 WebRtcSpl_MaxValueW16; 189int16_t WebRtcSpl_MaxValueW16C(const int16_t* vector, size_t length); 190#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 191int16_t WebRtcSpl_MaxValueW16Neon(const int16_t* vector, size_t length); 192#endif 193#if defined(MIPS32_LE) 194int16_t WebRtcSpl_MaxValueW16_mips(const int16_t* vector, size_t length); 195#endif 196 197// Returns the maximum value of a 32-bit vector. 198// 199// Input: 200// - vector : 32-bit input vector. 201// - length : Number of samples in vector. 202// 203// Return value : Maximum sample value in |vector|. 204typedef int32_t (*MaxValueW32)(const int32_t* vector, size_t length); 205extern MaxValueW32 WebRtcSpl_MaxValueW32; 206int32_t WebRtcSpl_MaxValueW32C(const int32_t* vector, size_t length); 207#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 208int32_t WebRtcSpl_MaxValueW32Neon(const int32_t* vector, size_t length); 209#endif 210#if defined(MIPS32_LE) 211int32_t WebRtcSpl_MaxValueW32_mips(const int32_t* vector, size_t length); 212#endif 213 214// Returns the minimum value of a 16-bit vector. 215// 216// Input: 217// - vector : 16-bit input vector. 218// - length : Number of samples in vector. 219// 220// Return value : Minimum sample value in |vector|. 221typedef int16_t (*MinValueW16)(const int16_t* vector, size_t length); 222extern MinValueW16 WebRtcSpl_MinValueW16; 223int16_t WebRtcSpl_MinValueW16C(const int16_t* vector, size_t length); 224#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 225int16_t WebRtcSpl_MinValueW16Neon(const int16_t* vector, size_t length); 226#endif 227#if defined(MIPS32_LE) 228int16_t WebRtcSpl_MinValueW16_mips(const int16_t* vector, size_t length); 229#endif 230 231// Returns the minimum value of a 32-bit vector. 232// 233// Input: 234// - vector : 32-bit input vector. 235// - length : Number of samples in vector. 236// 237// Return value : Minimum sample value in |vector|. 238typedef int32_t (*MinValueW32)(const int32_t* vector, size_t length); 239extern MinValueW32 WebRtcSpl_MinValueW32; 240int32_t WebRtcSpl_MinValueW32C(const int32_t* vector, size_t length); 241#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 242int32_t WebRtcSpl_MinValueW32Neon(const int32_t* vector, size_t length); 243#endif 244#if defined(MIPS32_LE) 245int32_t WebRtcSpl_MinValueW32_mips(const int32_t* vector, size_t length); 246#endif 247 248// Returns the vector index to the largest absolute value of a 16-bit vector. 249// 250// Input: 251// - vector : 16-bit input vector. 252// - length : Number of samples in vector. 253// 254// Return value : Index to the maximum absolute value in vector. 255// If there are multiple equal maxima, return the index of the 256// first. -32768 will always have precedence over 32767 (despite 257// -32768 presenting an int16 absolute value of 32767). 258size_t WebRtcSpl_MaxAbsIndexW16(const int16_t* vector, size_t length); 259 260// Returns the vector index to the maximum sample value of a 16-bit vector. 261// 262// Input: 263// - vector : 16-bit input vector. 264// - length : Number of samples in vector. 265// 266// Return value : Index to the maximum value in vector (if multiple 267// indexes have the maximum, return the first). 268size_t WebRtcSpl_MaxIndexW16(const int16_t* vector, size_t length); 269 270// Returns the vector index to the maximum sample value of a 32-bit vector. 271// 272// Input: 273// - vector : 32-bit input vector. 274// - length : Number of samples in vector. 275// 276// Return value : Index to the maximum value in vector (if multiple 277// indexes have the maximum, return the first). 278size_t WebRtcSpl_MaxIndexW32(const int32_t* vector, size_t length); 279 280// Returns the vector index to the minimum sample value of a 16-bit vector. 281// 282// Input: 283// - vector : 16-bit input vector. 284// - length : Number of samples in vector. 285// 286// Return value : Index to the mimimum value in vector (if multiple 287// indexes have the minimum, return the first). 288size_t WebRtcSpl_MinIndexW16(const int16_t* vector, size_t length); 289 290// Returns the vector index to the minimum sample value of a 32-bit vector. 291// 292// Input: 293// - vector : 32-bit input vector. 294// - length : Number of samples in vector. 295// 296// Return value : Index to the mimimum value in vector (if multiple 297// indexes have the minimum, return the first). 298size_t WebRtcSpl_MinIndexW32(const int32_t* vector, size_t length); 299 300// End: Minimum and maximum operations. 301 302 303// Vector scaling operations. Implementation in vector_scaling_operations.c. 304// Description at bottom of file. 305void WebRtcSpl_VectorBitShiftW16(int16_t* out_vector, 306 size_t vector_length, 307 const int16_t* in_vector, 308 int16_t right_shifts); 309void WebRtcSpl_VectorBitShiftW32(int32_t* out_vector, 310 size_t vector_length, 311 const int32_t* in_vector, 312 int16_t right_shifts); 313void WebRtcSpl_VectorBitShiftW32ToW16(int16_t* out_vector, 314 size_t vector_length, 315 const int32_t* in_vector, 316 int right_shifts); 317void WebRtcSpl_ScaleVector(const int16_t* in_vector, 318 int16_t* out_vector, 319 int16_t gain, 320 size_t vector_length, 321 int16_t right_shifts); 322void WebRtcSpl_ScaleVectorWithSat(const int16_t* in_vector, 323 int16_t* out_vector, 324 int16_t gain, 325 size_t vector_length, 326 int16_t right_shifts); 327void WebRtcSpl_ScaleAndAddVectors(const int16_t* in_vector1, 328 int16_t gain1, int right_shifts1, 329 const int16_t* in_vector2, 330 int16_t gain2, int right_shifts2, 331 int16_t* out_vector, 332 size_t vector_length); 333 334// The functions (with related pointer) perform the vector operation: 335// out_vector[k] = ((scale1 * in_vector1[k]) + (scale2 * in_vector2[k]) 336// + round_value) >> right_shifts, 337// where round_value = (1 << right_shifts) >> 1. 338// 339// Input: 340// - in_vector1 : Input vector 1 341// - in_vector1_scale : Gain to be used for vector 1 342// - in_vector2 : Input vector 2 343// - in_vector2_scale : Gain to be used for vector 2 344// - right_shifts : Number of right bit shifts to be applied 345// - length : Number of elements in the input vectors 346// 347// Output: 348// - out_vector : Output vector 349// Return value : 0 if OK, -1 if (in_vector1 == NULL 350// || in_vector2 == NULL || out_vector == NULL 351// || length <= 0 || right_shift < 0). 352typedef int (*ScaleAndAddVectorsWithRound)(const int16_t* in_vector1, 353 int16_t in_vector1_scale, 354 const int16_t* in_vector2, 355 int16_t in_vector2_scale, 356 int right_shifts, 357 int16_t* out_vector, 358 size_t length); 359extern ScaleAndAddVectorsWithRound WebRtcSpl_ScaleAndAddVectorsWithRound; 360int WebRtcSpl_ScaleAndAddVectorsWithRoundC(const int16_t* in_vector1, 361 int16_t in_vector1_scale, 362 const int16_t* in_vector2, 363 int16_t in_vector2_scale, 364 int right_shifts, 365 int16_t* out_vector, 366 size_t length); 367#if defined(MIPS_DSP_R1_LE) 368int WebRtcSpl_ScaleAndAddVectorsWithRound_mips(const int16_t* in_vector1, 369 int16_t in_vector1_scale, 370 const int16_t* in_vector2, 371 int16_t in_vector2_scale, 372 int right_shifts, 373 int16_t* out_vector, 374 size_t length); 375#endif 376// End: Vector scaling operations. 377 378// iLBC specific functions. Implementations in ilbc_specific_functions.c. 379// Description at bottom of file. 380void WebRtcSpl_ReverseOrderMultArrayElements(int16_t* out_vector, 381 const int16_t* in_vector, 382 const int16_t* window, 383 size_t vector_length, 384 int16_t right_shifts); 385void WebRtcSpl_ElementwiseVectorMult(int16_t* out_vector, 386 const int16_t* in_vector, 387 const int16_t* window, 388 size_t vector_length, 389 int16_t right_shifts); 390void WebRtcSpl_AddVectorsAndShift(int16_t* out_vector, 391 const int16_t* in_vector1, 392 const int16_t* in_vector2, 393 size_t vector_length, 394 int16_t right_shifts); 395void WebRtcSpl_AddAffineVectorToVector(int16_t* out_vector, 396 int16_t* in_vector, 397 int16_t gain, 398 int32_t add_constant, 399 int16_t right_shifts, 400 size_t vector_length); 401void WebRtcSpl_AffineTransformVector(int16_t* out_vector, 402 int16_t* in_vector, 403 int16_t gain, 404 int32_t add_constant, 405 int16_t right_shifts, 406 size_t vector_length); 407// End: iLBC specific functions. 408 409// Signal processing operations. 410 411// A 32-bit fix-point implementation of auto-correlation computation 412// 413// Input: 414// - in_vector : Vector to calculate autocorrelation upon 415// - in_vector_length : Length (in samples) of |vector| 416// - order : The order up to which the autocorrelation should be 417// calculated 418// 419// Output: 420// - result : auto-correlation values (values should be seen 421// relative to each other since the absolute values 422// might have been down shifted to avoid overflow) 423// 424// - scale : The number of left shifts required to obtain the 425// auto-correlation in Q0 426// 427// Return value : Number of samples in |result|, i.e. (order+1) 428size_t WebRtcSpl_AutoCorrelation(const int16_t* in_vector, 429 size_t in_vector_length, 430 size_t order, 431 int32_t* result, 432 int* scale); 433 434// A 32-bit fix-point implementation of the Levinson-Durbin algorithm that 435// does NOT use the 64 bit class 436// 437// Input: 438// - auto_corr : Vector with autocorrelation values of length >= |order|+1 439// - order : The LPC filter order (support up to order 20) 440// 441// Output: 442// - lpc_coef : lpc_coef[0..order] LPC coefficients in Q12 443// - refl_coef : refl_coef[0...order-1]| Reflection coefficients in Q15 444// 445// Return value : 1 for stable 0 for unstable 446int16_t WebRtcSpl_LevinsonDurbin(const int32_t* auto_corr, 447 int16_t* lpc_coef, 448 int16_t* refl_coef, 449 size_t order); 450 451// Converts reflection coefficients |refl_coef| to LPC coefficients |lpc_coef|. 452// This version is a 16 bit operation. 453// 454// NOTE: The 16 bit refl_coef -> lpc_coef conversion might result in a 455// "slightly unstable" filter (i.e., a pole just outside the unit circle) in 456// "rare" cases even if the reflection coefficients are stable. 457// 458// Input: 459// - refl_coef : Reflection coefficients in Q15 that should be converted 460// to LPC coefficients 461// - use_order : Number of coefficients in |refl_coef| 462// 463// Output: 464// - lpc_coef : LPC coefficients in Q12 465void WebRtcSpl_ReflCoefToLpc(const int16_t* refl_coef, 466 int use_order, 467 int16_t* lpc_coef); 468 469// Converts LPC coefficients |lpc_coef| to reflection coefficients |refl_coef|. 470// This version is a 16 bit operation. 471// The conversion is implemented by the step-down algorithm. 472// 473// Input: 474// - lpc_coef : LPC coefficients in Q12, that should be converted to 475// reflection coefficients 476// - use_order : Number of coefficients in |lpc_coef| 477// 478// Output: 479// - refl_coef : Reflection coefficients in Q15. 480void WebRtcSpl_LpcToReflCoef(int16_t* lpc_coef, 481 int use_order, 482 int16_t* refl_coef); 483 484// Calculates reflection coefficients (16 bit) from auto-correlation values 485// 486// Input: 487// - auto_corr : Auto-correlation values 488// - use_order : Number of coefficients wanted be calculated 489// 490// Output: 491// - refl_coef : Reflection coefficients in Q15. 492void WebRtcSpl_AutoCorrToReflCoef(const int32_t* auto_corr, 493 int use_order, 494 int16_t* refl_coef); 495 496// The functions (with related pointer) calculate the cross-correlation between 497// two sequences |seq1| and |seq2|. 498// |seq1| is fixed and |seq2| slides as the pointer is increased with the 499// amount |step_seq2|. Note the arguments should obey the relationship: 500// |dim_seq| - 1 + |step_seq2| * (|dim_cross_correlation| - 1) < 501// buffer size of |seq2| 502// 503// Input: 504// - seq1 : First sequence (fixed throughout the correlation) 505// - seq2 : Second sequence (slides |step_vector2| for each 506// new correlation) 507// - dim_seq : Number of samples to use in the cross-correlation 508// - dim_cross_correlation : Number of cross-correlations to calculate (the 509// start position for |vector2| is updated for each 510// new one) 511// - right_shifts : Number of right bit shifts to use. This will 512// become the output Q-domain. 513// - step_seq2 : How many (positive or negative) steps the 514// |vector2| pointer should be updated for each new 515// cross-correlation value. 516// 517// Output: 518// - cross_correlation : The cross-correlation in Q(-right_shifts) 519typedef void (*CrossCorrelation)(int32_t* cross_correlation, 520 const int16_t* seq1, 521 const int16_t* seq2, 522 size_t dim_seq, 523 size_t dim_cross_correlation, 524 int right_shifts, 525 int step_seq2); 526extern CrossCorrelation WebRtcSpl_CrossCorrelation; 527void WebRtcSpl_CrossCorrelationC(int32_t* cross_correlation, 528 const int16_t* seq1, 529 const int16_t* seq2, 530 size_t dim_seq, 531 size_t dim_cross_correlation, 532 int right_shifts, 533 int step_seq2); 534#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 535void WebRtcSpl_CrossCorrelationNeon(int32_t* cross_correlation, 536 const int16_t* seq1, 537 const int16_t* seq2, 538 size_t dim_seq, 539 size_t dim_cross_correlation, 540 int right_shifts, 541 int step_seq2); 542#endif 543#if defined(MIPS32_LE) 544void WebRtcSpl_CrossCorrelation_mips(int32_t* cross_correlation, 545 const int16_t* seq1, 546 const int16_t* seq2, 547 size_t dim_seq, 548 size_t dim_cross_correlation, 549 int right_shifts, 550 int step_seq2); 551#endif 552 553// Creates (the first half of) a Hanning window. Size must be at least 1 and 554// at most 512. 555// 556// Input: 557// - size : Length of the requested Hanning window (1 to 512) 558// 559// Output: 560// - window : Hanning vector in Q14. 561void WebRtcSpl_GetHanningWindow(int16_t* window, size_t size); 562 563// Calculates y[k] = sqrt(1 - x[k]^2) for each element of the input vector 564// |in_vector|. Input and output values are in Q15. 565// 566// Inputs: 567// - in_vector : Values to calculate sqrt(1 - x^2) of 568// - vector_length : Length of vector |in_vector| 569// 570// Output: 571// - out_vector : Output values in Q15 572void WebRtcSpl_SqrtOfOneMinusXSquared(int16_t* in_vector, 573 size_t vector_length, 574 int16_t* out_vector); 575// End: Signal processing operations. 576 577// Randomization functions. Implementations collected in 578// randomization_functions.c and descriptions at bottom of this file. 579int16_t WebRtcSpl_RandU(uint32_t* seed); 580int16_t WebRtcSpl_RandN(uint32_t* seed); 581int16_t WebRtcSpl_RandUArray(int16_t* vector, 582 int16_t vector_length, 583 uint32_t* seed); 584// End: Randomization functions. 585 586// Math functions 587int32_t WebRtcSpl_Sqrt(int32_t value); 588int32_t WebRtcSpl_SqrtFloor(int32_t value); 589 590// Divisions. Implementations collected in division_operations.c and 591// descriptions at bottom of this file. 592uint32_t WebRtcSpl_DivU32U16(uint32_t num, uint16_t den); 593int32_t WebRtcSpl_DivW32W16(int32_t num, int16_t den); 594int16_t WebRtcSpl_DivW32W16ResW16(int32_t num, int16_t den); 595int32_t WebRtcSpl_DivResultInQ31(int32_t num, int32_t den); 596int32_t WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low); 597// End: Divisions. 598 599int32_t WebRtcSpl_Energy(int16_t* vector, 600 size_t vector_length, 601 int* scale_factor); 602 603// Calculates the dot product between two (int16_t) vectors. 604// 605// Input: 606// - vector1 : Vector 1 607// - vector2 : Vector 2 608// - vector_length : Number of samples used in the dot product 609// - scaling : The number of right bit shifts to apply on each term 610// during calculation to avoid overflow, i.e., the 611// output will be in Q(-|scaling|) 612// 613// Return value : The dot product in Q(-scaling) 614int32_t WebRtcSpl_DotProductWithScale(const int16_t* vector1, 615 const int16_t* vector2, 616 size_t length, 617 int scaling); 618 619// Filter operations. 620size_t WebRtcSpl_FilterAR(const int16_t* ar_coef, 621 size_t ar_coef_length, 622 const int16_t* in_vector, 623 size_t in_vector_length, 624 int16_t* filter_state, 625 size_t filter_state_length, 626 int16_t* filter_state_low, 627 size_t filter_state_low_length, 628 int16_t* out_vector, 629 int16_t* out_vector_low, 630 size_t out_vector_low_length); 631 632// WebRtcSpl_FilterMAFastQ12(...) 633// 634// Performs a MA filtering on a vector in Q12 635// 636// Input: 637// - in_vector : Input samples (state in positions 638// in_vector[-order] .. in_vector[-1]) 639// - ma_coef : Filter coefficients (in Q12) 640// - ma_coef_length : Number of B coefficients (order+1) 641// - vector_length : Number of samples to be filtered 642// 643// Output: 644// - out_vector : Filtered samples 645// 646void WebRtcSpl_FilterMAFastQ12(const int16_t* in_vector, 647 int16_t* out_vector, 648 const int16_t* ma_coef, 649 size_t ma_coef_length, 650 size_t vector_length); 651 652// Performs a AR filtering on a vector in Q12 653// Input: 654// - data_in : Input samples 655// - data_out : State information in positions 656// data_out[-order] .. data_out[-1] 657// - coefficients : Filter coefficients (in Q12) 658// - coefficients_length: Number of coefficients (order+1) 659// - data_length : Number of samples to be filtered 660// Output: 661// - data_out : Filtered samples 662void WebRtcSpl_FilterARFastQ12(const int16_t* data_in, 663 int16_t* data_out, 664 const int16_t* __restrict coefficients, 665 size_t coefficients_length, 666 size_t data_length); 667 668// The functions (with related pointer) perform a MA down sampling filter 669// on a vector. 670// Input: 671// - data_in : Input samples (state in positions 672// data_in[-order] .. data_in[-1]) 673// - data_in_length : Number of samples in |data_in| to be filtered. 674// This must be at least 675// |delay| + |factor|*(|out_vector_length|-1) + 1) 676// - data_out_length : Number of down sampled samples desired 677// - coefficients : Filter coefficients (in Q12) 678// - coefficients_length: Number of coefficients (order+1) 679// - factor : Decimation factor 680// - delay : Delay of filter (compensated for in out_vector) 681// Output: 682// - data_out : Filtered samples 683// Return value : 0 if OK, -1 if |in_vector| is too short 684typedef int (*DownsampleFast)(const int16_t* data_in, 685 size_t data_in_length, 686 int16_t* data_out, 687 size_t data_out_length, 688 const int16_t* __restrict coefficients, 689 size_t coefficients_length, 690 int factor, 691 size_t delay); 692extern DownsampleFast WebRtcSpl_DownsampleFast; 693int WebRtcSpl_DownsampleFastC(const int16_t* data_in, 694 size_t data_in_length, 695 int16_t* data_out, 696 size_t data_out_length, 697 const int16_t* __restrict coefficients, 698 size_t coefficients_length, 699 int factor, 700 size_t delay); 701#if (defined WEBRTC_DETECT_NEON) || (defined WEBRTC_HAS_NEON) 702int WebRtcSpl_DownsampleFastNeon(const int16_t* data_in, 703 size_t data_in_length, 704 int16_t* data_out, 705 size_t data_out_length, 706 const int16_t* __restrict coefficients, 707 size_t coefficients_length, 708 int factor, 709 size_t delay); 710#endif 711#if defined(MIPS32_LE) 712int WebRtcSpl_DownsampleFast_mips(const int16_t* data_in, 713 size_t data_in_length, 714 int16_t* data_out, 715 size_t data_out_length, 716 const int16_t* __restrict coefficients, 717 size_t coefficients_length, 718 int factor, 719 size_t delay); 720#endif 721 722// End: Filter operations. 723 724// FFT operations 725 726int WebRtcSpl_ComplexFFT(int16_t vector[], int stages, int mode); 727int WebRtcSpl_ComplexIFFT(int16_t vector[], int stages, int mode); 728 729// Treat a 16-bit complex data buffer |complex_data| as an array of 32-bit 730// values, and swap elements whose indexes are bit-reverses of each other. 731// 732// Input: 733// - complex_data : Complex data buffer containing 2^|stages| real 734// elements interleaved with 2^|stages| imaginary 735// elements: [Re Im Re Im Re Im....] 736// - stages : Number of FFT stages. Must be at least 3 and at most 737// 10, since the table WebRtcSpl_kSinTable1024[] is 1024 738// elements long. 739// 740// Output: 741// - complex_data : The complex data buffer. 742 743void WebRtcSpl_ComplexBitReverse(int16_t* __restrict complex_data, int stages); 744 745// End: FFT operations 746 747/************************************************************ 748 * 749 * RESAMPLING FUNCTIONS AND THEIR STRUCTS ARE DEFINED BELOW 750 * 751 ************************************************************/ 752 753/******************************************************************* 754 * resample.c 755 * 756 * Includes the following resampling combinations 757 * 22 kHz -> 16 kHz 758 * 16 kHz -> 22 kHz 759 * 22 kHz -> 8 kHz 760 * 8 kHz -> 22 kHz 761 * 762 ******************************************************************/ 763 764// state structure for 22 -> 16 resampler 765typedef struct { 766 int32_t S_22_44[8]; 767 int32_t S_44_32[8]; 768 int32_t S_32_16[8]; 769} WebRtcSpl_State22khzTo16khz; 770 771void WebRtcSpl_Resample22khzTo16khz(const int16_t* in, 772 int16_t* out, 773 WebRtcSpl_State22khzTo16khz* state, 774 int32_t* tmpmem); 775 776void WebRtcSpl_ResetResample22khzTo16khz(WebRtcSpl_State22khzTo16khz* state); 777 778// state structure for 16 -> 22 resampler 779typedef struct { 780 int32_t S_16_32[8]; 781 int32_t S_32_22[8]; 782} WebRtcSpl_State16khzTo22khz; 783 784void WebRtcSpl_Resample16khzTo22khz(const int16_t* in, 785 int16_t* out, 786 WebRtcSpl_State16khzTo22khz* state, 787 int32_t* tmpmem); 788 789void WebRtcSpl_ResetResample16khzTo22khz(WebRtcSpl_State16khzTo22khz* state); 790 791// state structure for 22 -> 8 resampler 792typedef struct { 793 int32_t S_22_22[16]; 794 int32_t S_22_16[8]; 795 int32_t S_16_8[8]; 796} WebRtcSpl_State22khzTo8khz; 797 798void WebRtcSpl_Resample22khzTo8khz(const int16_t* in, int16_t* out, 799 WebRtcSpl_State22khzTo8khz* state, 800 int32_t* tmpmem); 801 802void WebRtcSpl_ResetResample22khzTo8khz(WebRtcSpl_State22khzTo8khz* state); 803 804// state structure for 8 -> 22 resampler 805typedef struct { 806 int32_t S_8_16[8]; 807 int32_t S_16_11[8]; 808 int32_t S_11_22[8]; 809} WebRtcSpl_State8khzTo22khz; 810 811void WebRtcSpl_Resample8khzTo22khz(const int16_t* in, int16_t* out, 812 WebRtcSpl_State8khzTo22khz* state, 813 int32_t* tmpmem); 814 815void WebRtcSpl_ResetResample8khzTo22khz(WebRtcSpl_State8khzTo22khz* state); 816 817/******************************************************************* 818 * resample_fractional.c 819 * Functions for internal use in the other resample functions 820 * 821 * Includes the following resampling combinations 822 * 48 kHz -> 32 kHz 823 * 32 kHz -> 24 kHz 824 * 44 kHz -> 32 kHz 825 * 826 ******************************************************************/ 827 828void WebRtcSpl_Resample48khzTo32khz(const int32_t* In, int32_t* Out, size_t K); 829 830void WebRtcSpl_Resample32khzTo24khz(const int32_t* In, int32_t* Out, size_t K); 831 832void WebRtcSpl_Resample44khzTo32khz(const int32_t* In, int32_t* Out, size_t K); 833 834/******************************************************************* 835 * resample_48khz.c 836 * 837 * Includes the following resampling combinations 838 * 48 kHz -> 16 kHz 839 * 16 kHz -> 48 kHz 840 * 48 kHz -> 8 kHz 841 * 8 kHz -> 48 kHz 842 * 843 ******************************************************************/ 844 845typedef struct { 846 int32_t S_48_48[16]; 847 int32_t S_48_32[8]; 848 int32_t S_32_16[8]; 849} WebRtcSpl_State48khzTo16khz; 850 851void WebRtcSpl_Resample48khzTo16khz(const int16_t* in, int16_t* out, 852 WebRtcSpl_State48khzTo16khz* state, 853 int32_t* tmpmem); 854 855void WebRtcSpl_ResetResample48khzTo16khz(WebRtcSpl_State48khzTo16khz* state); 856 857typedef struct { 858 int32_t S_16_32[8]; 859 int32_t S_32_24[8]; 860 int32_t S_24_48[8]; 861} WebRtcSpl_State16khzTo48khz; 862 863void WebRtcSpl_Resample16khzTo48khz(const int16_t* in, int16_t* out, 864 WebRtcSpl_State16khzTo48khz* state, 865 int32_t* tmpmem); 866 867void WebRtcSpl_ResetResample16khzTo48khz(WebRtcSpl_State16khzTo48khz* state); 868 869typedef struct { 870 int32_t S_48_24[8]; 871 int32_t S_24_24[16]; 872 int32_t S_24_16[8]; 873 int32_t S_16_8[8]; 874} WebRtcSpl_State48khzTo8khz; 875 876void WebRtcSpl_Resample48khzTo8khz(const int16_t* in, int16_t* out, 877 WebRtcSpl_State48khzTo8khz* state, 878 int32_t* tmpmem); 879 880void WebRtcSpl_ResetResample48khzTo8khz(WebRtcSpl_State48khzTo8khz* state); 881 882typedef struct { 883 int32_t S_8_16[8]; 884 int32_t S_16_12[8]; 885 int32_t S_12_24[8]; 886 int32_t S_24_48[8]; 887} WebRtcSpl_State8khzTo48khz; 888 889void WebRtcSpl_Resample8khzTo48khz(const int16_t* in, int16_t* out, 890 WebRtcSpl_State8khzTo48khz* state, 891 int32_t* tmpmem); 892 893void WebRtcSpl_ResetResample8khzTo48khz(WebRtcSpl_State8khzTo48khz* state); 894 895/******************************************************************* 896 * resample_by_2.c 897 * 898 * Includes down and up sampling by a factor of two. 899 * 900 ******************************************************************/ 901 902void WebRtcSpl_DownsampleBy2(const int16_t* in, size_t len, 903 int16_t* out, int32_t* filtState); 904 905void WebRtcSpl_UpsampleBy2(const int16_t* in, size_t len, 906 int16_t* out, int32_t* filtState); 907 908/************************************************************ 909 * END OF RESAMPLING FUNCTIONS 910 ************************************************************/ 911void WebRtcSpl_AnalysisQMF(const int16_t* in_data, 912 size_t in_data_length, 913 int16_t* low_band, 914 int16_t* high_band, 915 int32_t* filter_state1, 916 int32_t* filter_state2); 917void WebRtcSpl_SynthesisQMF(const int16_t* low_band, 918 const int16_t* high_band, 919 size_t band_length, 920 int16_t* out_data, 921 int32_t* filter_state1, 922 int32_t* filter_state2); 923 924#ifdef __cplusplus 925} 926#endif // __cplusplus 927#endif // WEBRTC_SPL_SIGNAL_PROCESSING_LIBRARY_H_ 928 929// 930// WebRtcSpl_AddSatW16(...) 931// WebRtcSpl_AddSatW32(...) 932// 933// Returns the result of a saturated 16-bit, respectively 32-bit, addition of 934// the numbers specified by the |var1| and |var2| parameters. 935// 936// Input: 937// - var1 : Input variable 1 938// - var2 : Input variable 2 939// 940// Return value : Added and saturated value 941// 942 943// 944// WebRtcSpl_SubSatW16(...) 945// WebRtcSpl_SubSatW32(...) 946// 947// Returns the result of a saturated 16-bit, respectively 32-bit, subtraction 948// of the numbers specified by the |var1| and |var2| parameters. 949// 950// Input: 951// - var1 : Input variable 1 952// - var2 : Input variable 2 953// 954// Returned value : Subtracted and saturated value 955// 956 957// 958// WebRtcSpl_GetSizeInBits(...) 959// 960// Returns the # of bits that are needed at the most to represent the number 961// specified by the |value| parameter. 962// 963// Input: 964// - value : Input value 965// 966// Return value : Number of bits needed to represent |value| 967// 968 969// 970// WebRtcSpl_NormW32(...) 971// 972// Norm returns the # of left shifts required to 32-bit normalize the 32-bit 973// signed number specified by the |value| parameter. 974// 975// Input: 976// - value : Input value 977// 978// Return value : Number of bit shifts needed to 32-bit normalize |value| 979// 980 981// 982// WebRtcSpl_NormW16(...) 983// 984// Norm returns the # of left shifts required to 16-bit normalize the 16-bit 985// signed number specified by the |value| parameter. 986// 987// Input: 988// - value : Input value 989// 990// Return value : Number of bit shifts needed to 32-bit normalize |value| 991// 992 993// 994// WebRtcSpl_NormU32(...) 995// 996// Norm returns the # of left shifts required to 32-bit normalize the unsigned 997// 32-bit number specified by the |value| parameter. 998// 999// Input: 1000// - value : Input value 1001// 1002// Return value : Number of bit shifts needed to 32-bit normalize |value| 1003// 1004 1005// 1006// WebRtcSpl_GetScalingSquare(...) 1007// 1008// Returns the # of bits required to scale the samples specified in the 1009// |in_vector| parameter so that, if the squares of the samples are added the 1010// # of times specified by the |times| parameter, the 32-bit addition will not 1011// overflow (result in int32_t). 1012// 1013// Input: 1014// - in_vector : Input vector to check scaling on 1015// - in_vector_length : Samples in |in_vector| 1016// - times : Number of additions to be performed 1017// 1018// Return value : Number of right bit shifts needed to avoid 1019// overflow in the addition calculation 1020// 1021 1022// 1023// WebRtcSpl_MemSetW16(...) 1024// 1025// Sets all the values in the int16_t vector |vector| of length 1026// |vector_length| to the specified value |set_value| 1027// 1028// Input: 1029// - vector : Pointer to the int16_t vector 1030// - set_value : Value specified 1031// - vector_length : Length of vector 1032// 1033 1034// 1035// WebRtcSpl_MemSetW32(...) 1036// 1037// Sets all the values in the int32_t vector |vector| of length 1038// |vector_length| to the specified value |set_value| 1039// 1040// Input: 1041// - vector : Pointer to the int16_t vector 1042// - set_value : Value specified 1043// - vector_length : Length of vector 1044// 1045 1046// 1047// WebRtcSpl_MemCpyReversedOrder(...) 1048// 1049// Copies all the values from the source int16_t vector |in_vector| to a 1050// destination int16_t vector |out_vector|. It is done in reversed order, 1051// meaning that the first sample of |in_vector| is copied to the last sample of 1052// the |out_vector|. The procedure continues until the last sample of 1053// |in_vector| has been copied to the first sample of |out_vector|. This 1054// creates a reversed vector. Used in e.g. prediction in iLBC. 1055// 1056// Input: 1057// - in_vector : Pointer to the first sample in a int16_t vector 1058// of length |length| 1059// - vector_length : Number of elements to copy 1060// 1061// Output: 1062// - out_vector : Pointer to the last sample in a int16_t vector 1063// of length |length| 1064// 1065 1066// 1067// WebRtcSpl_CopyFromEndW16(...) 1068// 1069// Copies the rightmost |samples| of |in_vector| (of length |in_vector_length|) 1070// to the vector |out_vector|. 1071// 1072// Input: 1073// - in_vector : Input vector 1074// - in_vector_length : Number of samples in |in_vector| 1075// - samples : Number of samples to extract (from right side) 1076// from |in_vector| 1077// 1078// Output: 1079// - out_vector : Vector with the requested samples 1080// 1081 1082// 1083// WebRtcSpl_ZerosArrayW16(...) 1084// WebRtcSpl_ZerosArrayW32(...) 1085// 1086// Inserts the value "zero" in all positions of a w16 and a w32 vector 1087// respectively. 1088// 1089// Input: 1090// - vector_length : Number of samples in vector 1091// 1092// Output: 1093// - vector : Vector containing all zeros 1094// 1095 1096// 1097// WebRtcSpl_VectorBitShiftW16(...) 1098// WebRtcSpl_VectorBitShiftW32(...) 1099// 1100// Bit shifts all the values in a vector up or downwards. Different calls for 1101// int16_t and int32_t vectors respectively. 1102// 1103// Input: 1104// - vector_length : Length of vector 1105// - in_vector : Pointer to the vector that should be bit shifted 1106// - right_shifts : Number of right bit shifts (negative value gives left 1107// shifts) 1108// 1109// Output: 1110// - out_vector : Pointer to the result vector (can be the same as 1111// |in_vector|) 1112// 1113 1114// 1115// WebRtcSpl_VectorBitShiftW32ToW16(...) 1116// 1117// Bit shifts all the values in a int32_t vector up or downwards and 1118// stores the result as an int16_t vector. The function will saturate the 1119// signal if needed, before storing in the output vector. 1120// 1121// Input: 1122// - vector_length : Length of vector 1123// - in_vector : Pointer to the vector that should be bit shifted 1124// - right_shifts : Number of right bit shifts (negative value gives left 1125// shifts) 1126// 1127// Output: 1128// - out_vector : Pointer to the result vector (can be the same as 1129// |in_vector|) 1130// 1131 1132// 1133// WebRtcSpl_ScaleVector(...) 1134// 1135// Performs the vector operation: 1136// out_vector[k] = (gain*in_vector[k])>>right_shifts 1137// 1138// Input: 1139// - in_vector : Input vector 1140// - gain : Scaling gain 1141// - vector_length : Elements in the |in_vector| 1142// - right_shifts : Number of right bit shifts applied 1143// 1144// Output: 1145// - out_vector : Output vector (can be the same as |in_vector|) 1146// 1147 1148// 1149// WebRtcSpl_ScaleVectorWithSat(...) 1150// 1151// Performs the vector operation: 1152// out_vector[k] = SATURATE( (gain*in_vector[k])>>right_shifts ) 1153// 1154// Input: 1155// - in_vector : Input vector 1156// - gain : Scaling gain 1157// - vector_length : Elements in the |in_vector| 1158// - right_shifts : Number of right bit shifts applied 1159// 1160// Output: 1161// - out_vector : Output vector (can be the same as |in_vector|) 1162// 1163 1164// 1165// WebRtcSpl_ScaleAndAddVectors(...) 1166// 1167// Performs the vector operation: 1168// out_vector[k] = (gain1*in_vector1[k])>>right_shifts1 1169// + (gain2*in_vector2[k])>>right_shifts2 1170// 1171// Input: 1172// - in_vector1 : Input vector 1 1173// - gain1 : Gain to be used for vector 1 1174// - right_shifts1 : Right bit shift to be used for vector 1 1175// - in_vector2 : Input vector 2 1176// - gain2 : Gain to be used for vector 2 1177// - right_shifts2 : Right bit shift to be used for vector 2 1178// - vector_length : Elements in the input vectors 1179// 1180// Output: 1181// - out_vector : Output vector 1182// 1183 1184// 1185// WebRtcSpl_ReverseOrderMultArrayElements(...) 1186// 1187// Performs the vector operation: 1188// out_vector[n] = (in_vector[n]*window[-n])>>right_shifts 1189// 1190// Input: 1191// - in_vector : Input vector 1192// - window : Window vector (should be reversed). The pointer 1193// should be set to the last value in the vector 1194// - right_shifts : Number of right bit shift to be applied after the 1195// multiplication 1196// - vector_length : Number of elements in |in_vector| 1197// 1198// Output: 1199// - out_vector : Output vector (can be same as |in_vector|) 1200// 1201 1202// 1203// WebRtcSpl_ElementwiseVectorMult(...) 1204// 1205// Performs the vector operation: 1206// out_vector[n] = (in_vector[n]*window[n])>>right_shifts 1207// 1208// Input: 1209// - in_vector : Input vector 1210// - window : Window vector. 1211// - right_shifts : Number of right bit shift to be applied after the 1212// multiplication 1213// - vector_length : Number of elements in |in_vector| 1214// 1215// Output: 1216// - out_vector : Output vector (can be same as |in_vector|) 1217// 1218 1219// 1220// WebRtcSpl_AddVectorsAndShift(...) 1221// 1222// Performs the vector operation: 1223// out_vector[k] = (in_vector1[k] + in_vector2[k])>>right_shifts 1224// 1225// Input: 1226// - in_vector1 : Input vector 1 1227// - in_vector2 : Input vector 2 1228// - right_shifts : Number of right bit shift to be applied after the 1229// multiplication 1230// - vector_length : Number of elements in |in_vector1| and |in_vector2| 1231// 1232// Output: 1233// - out_vector : Output vector (can be same as |in_vector1|) 1234// 1235 1236// 1237// WebRtcSpl_AddAffineVectorToVector(...) 1238// 1239// Adds an affine transformed vector to another vector |out_vector|, i.e, 1240// performs 1241// out_vector[k] += (in_vector[k]*gain+add_constant)>>right_shifts 1242// 1243// Input: 1244// - in_vector : Input vector 1245// - gain : Gain value, used to multiply the in vector with 1246// - add_constant : Constant value to add (usually 1<<(right_shifts-1), 1247// but others can be used as well 1248// - right_shifts : Number of right bit shifts (0-16) 1249// - vector_length : Number of samples in |in_vector| and |out_vector| 1250// 1251// Output: 1252// - out_vector : Vector with the output 1253// 1254 1255// 1256// WebRtcSpl_AffineTransformVector(...) 1257// 1258// Affine transforms a vector, i.e, performs 1259// out_vector[k] = (in_vector[k]*gain+add_constant)>>right_shifts 1260// 1261// Input: 1262// - in_vector : Input vector 1263// - gain : Gain value, used to multiply the in vector with 1264// - add_constant : Constant value to add (usually 1<<(right_shifts-1), 1265// but others can be used as well 1266// - right_shifts : Number of right bit shifts (0-16) 1267// - vector_length : Number of samples in |in_vector| and |out_vector| 1268// 1269// Output: 1270// - out_vector : Vector with the output 1271// 1272 1273// 1274// WebRtcSpl_IncreaseSeed(...) 1275// 1276// Increases the seed (and returns the new value) 1277// 1278// Input: 1279// - seed : Seed for random calculation 1280// 1281// Output: 1282// - seed : Updated seed value 1283// 1284// Return value : The new seed value 1285// 1286 1287// 1288// WebRtcSpl_RandU(...) 1289// 1290// Produces a uniformly distributed value in the int16_t range 1291// 1292// Input: 1293// - seed : Seed for random calculation 1294// 1295// Output: 1296// - seed : Updated seed value 1297// 1298// Return value : Uniformly distributed value in the range 1299// [Word16_MIN...Word16_MAX] 1300// 1301 1302// 1303// WebRtcSpl_RandN(...) 1304// 1305// Produces a normal distributed value in the int16_t range 1306// 1307// Input: 1308// - seed : Seed for random calculation 1309// 1310// Output: 1311// - seed : Updated seed value 1312// 1313// Return value : N(0,1) value in the Q13 domain 1314// 1315 1316// 1317// WebRtcSpl_RandUArray(...) 1318// 1319// Produces a uniformly distributed vector with elements in the int16_t 1320// range 1321// 1322// Input: 1323// - vector_length : Samples wanted in the vector 1324// - seed : Seed for random calculation 1325// 1326// Output: 1327// - vector : Vector with the uniform values 1328// - seed : Updated seed value 1329// 1330// Return value : Number of samples in vector, i.e., |vector_length| 1331// 1332 1333// 1334// WebRtcSpl_Sqrt(...) 1335// 1336// Returns the square root of the input value |value|. The precision of this 1337// function is integer precision, i.e., sqrt(8) gives 2 as answer. 1338// If |value| is a negative number then 0 is returned. 1339// 1340// Algorithm: 1341// 1342// A sixth order Taylor Series expansion is used here to compute the square 1343// root of a number y^0.5 = (1+x)^0.5 1344// where 1345// x = y-1 1346// = 1+(x/2)-0.5*((x/2)^2+0.5*((x/2)^3-0.625*((x/2)^4+0.875*((x/2)^5) 1347// 0.5 <= x < 1 1348// 1349// Input: 1350// - value : Value to calculate sqrt of 1351// 1352// Return value : Result of the sqrt calculation 1353// 1354 1355// 1356// WebRtcSpl_SqrtFloor(...) 1357// 1358// Returns the square root of the input value |value|. The precision of this 1359// function is rounding down integer precision, i.e., sqrt(8) gives 2 as answer. 1360// If |value| is a negative number then 0 is returned. 1361// 1362// Algorithm: 1363// 1364// An iterative 4 cylce/bit routine 1365// 1366// Input: 1367// - value : Value to calculate sqrt of 1368// 1369// Return value : Result of the sqrt calculation 1370// 1371 1372// 1373// WebRtcSpl_DivU32U16(...) 1374// 1375// Divides a uint32_t |num| by a uint16_t |den|. 1376// 1377// If |den|==0, (uint32_t)0xFFFFFFFF is returned. 1378// 1379// Input: 1380// - num : Numerator 1381// - den : Denominator 1382// 1383// Return value : Result of the division (as a uint32_t), i.e., the 1384// integer part of num/den. 1385// 1386 1387// 1388// WebRtcSpl_DivW32W16(...) 1389// 1390// Divides a int32_t |num| by a int16_t |den|. 1391// 1392// If |den|==0, (int32_t)0x7FFFFFFF is returned. 1393// 1394// Input: 1395// - num : Numerator 1396// - den : Denominator 1397// 1398// Return value : Result of the division (as a int32_t), i.e., the 1399// integer part of num/den. 1400// 1401 1402// 1403// WebRtcSpl_DivW32W16ResW16(...) 1404// 1405// Divides a int32_t |num| by a int16_t |den|, assuming that the 1406// result is less than 32768, otherwise an unpredictable result will occur. 1407// 1408// If |den|==0, (int16_t)0x7FFF is returned. 1409// 1410// Input: 1411// - num : Numerator 1412// - den : Denominator 1413// 1414// Return value : Result of the division (as a int16_t), i.e., the 1415// integer part of num/den. 1416// 1417 1418// 1419// WebRtcSpl_DivResultInQ31(...) 1420// 1421// Divides a int32_t |num| by a int16_t |den|, assuming that the 1422// absolute value of the denominator is larger than the numerator, otherwise 1423// an unpredictable result will occur. 1424// 1425// Input: 1426// - num : Numerator 1427// - den : Denominator 1428// 1429// Return value : Result of the division in Q31. 1430// 1431 1432// 1433// WebRtcSpl_DivW32HiLow(...) 1434// 1435// Divides a int32_t |num| by a denominator in hi, low format. The 1436// absolute value of the denominator has to be larger (or equal to) the 1437// numerator. 1438// 1439// Input: 1440// - num : Numerator 1441// - den_hi : High part of denominator 1442// - den_low : Low part of denominator 1443// 1444// Return value : Divided value in Q31 1445// 1446 1447// 1448// WebRtcSpl_Energy(...) 1449// 1450// Calculates the energy of a vector 1451// 1452// Input: 1453// - vector : Vector which the energy should be calculated on 1454// - vector_length : Number of samples in vector 1455// 1456// Output: 1457// - scale_factor : Number of left bit shifts needed to get the physical 1458// energy value, i.e, to get the Q0 value 1459// 1460// Return value : Energy value in Q(-|scale_factor|) 1461// 1462 1463// 1464// WebRtcSpl_FilterAR(...) 1465// 1466// Performs a 32-bit AR filtering on a vector in Q12 1467// 1468// Input: 1469// - ar_coef : AR-coefficient vector (values in Q12), 1470// ar_coef[0] must be 4096. 1471// - ar_coef_length : Number of coefficients in |ar_coef|. 1472// - in_vector : Vector to be filtered. 1473// - in_vector_length : Number of samples in |in_vector|. 1474// - filter_state : Current state (higher part) of the filter. 1475// - filter_state_length : Length (in samples) of |filter_state|. 1476// - filter_state_low : Current state (lower part) of the filter. 1477// - filter_state_low_length : Length (in samples) of |filter_state_low|. 1478// - out_vector_low_length : Maximum length (in samples) of 1479// |out_vector_low|. 1480// 1481// Output: 1482// - filter_state : Updated state (upper part) vector. 1483// - filter_state_low : Updated state (lower part) vector. 1484// - out_vector : Vector containing the upper part of the 1485// filtered values. 1486// - out_vector_low : Vector containing the lower part of the 1487// filtered values. 1488// 1489// Return value : Number of samples in the |out_vector|. 1490// 1491 1492// 1493// WebRtcSpl_ComplexIFFT(...) 1494// 1495// Complex Inverse FFT 1496// 1497// Computes an inverse complex 2^|stages|-point FFT on the input vector, which 1498// is in bit-reversed order. The original content of the vector is destroyed in 1499// the process, since the input is overwritten by the output, normal-ordered, 1500// FFT vector. With X as the input complex vector, y as the output complex 1501// vector and with M = 2^|stages|, the following is computed: 1502// 1503// M-1 1504// y(k) = sum[X(i)*[cos(2*pi*i*k/M) + j*sin(2*pi*i*k/M)]] 1505// i=0 1506// 1507// The implementations are optimized for speed, not for code size. It uses the 1508// decimation-in-time algorithm with radix-2 butterfly technique. 1509// 1510// Input: 1511// - vector : In pointer to complex vector containing 2^|stages| 1512// real elements interleaved with 2^|stages| imaginary 1513// elements. 1514// [ReImReImReIm....] 1515// The elements are in Q(-scale) domain, see more on Return 1516// Value below. 1517// 1518// - stages : Number of FFT stages. Must be at least 3 and at most 10, 1519// since the table WebRtcSpl_kSinTable1024[] is 1024 1520// elements long. 1521// 1522// - mode : This parameter gives the user to choose how the FFT 1523// should work. 1524// mode==0: Low-complexity and Low-accuracy mode 1525// mode==1: High-complexity and High-accuracy mode 1526// 1527// Output: 1528// - vector : Out pointer to the FFT vector (the same as input). 1529// 1530// Return Value : The scale value that tells the number of left bit shifts 1531// that the elements in the |vector| should be shifted with 1532// in order to get Q0 values, i.e. the physically correct 1533// values. The scale parameter is always 0 or positive, 1534// except if N>1024 (|stages|>10), which returns a scale 1535// value of -1, indicating error. 1536// 1537 1538// 1539// WebRtcSpl_ComplexFFT(...) 1540// 1541// Complex FFT 1542// 1543// Computes a complex 2^|stages|-point FFT on the input vector, which is in 1544// bit-reversed order. The original content of the vector is destroyed in 1545// the process, since the input is overwritten by the output, normal-ordered, 1546// FFT vector. With x as the input complex vector, Y as the output complex 1547// vector and with M = 2^|stages|, the following is computed: 1548// 1549// M-1 1550// Y(k) = 1/M * sum[x(i)*[cos(2*pi*i*k/M) + j*sin(2*pi*i*k/M)]] 1551// i=0 1552// 1553// The implementations are optimized for speed, not for code size. It uses the 1554// decimation-in-time algorithm with radix-2 butterfly technique. 1555// 1556// This routine prevents overflow by scaling by 2 before each FFT stage. This is 1557// a fixed scaling, for proper normalization - there will be log2(n) passes, so 1558// this results in an overall factor of 1/n, distributed to maximize arithmetic 1559// accuracy. 1560// 1561// Input: 1562// - vector : In pointer to complex vector containing 2^|stages| real 1563// elements interleaved with 2^|stages| imaginary elements. 1564// [ReImReImReIm....] 1565// The output is in the Q0 domain. 1566// 1567// - stages : Number of FFT stages. Must be at least 3 and at most 10, 1568// since the table WebRtcSpl_kSinTable1024[] is 1024 1569// elements long. 1570// 1571// - mode : This parameter gives the user to choose how the FFT 1572// should work. 1573// mode==0: Low-complexity and Low-accuracy mode 1574// mode==1: High-complexity and High-accuracy mode 1575// 1576// Output: 1577// - vector : The output FFT vector is in the Q0 domain. 1578// 1579// Return value : The scale parameter is always 0, except if N>1024, 1580// which returns a scale value of -1, indicating error. 1581// 1582 1583// 1584// WebRtcSpl_AnalysisQMF(...) 1585// 1586// Splits a 0-2*F Hz signal into two sub bands: 0-F Hz and F-2*F Hz. The 1587// current version has F = 8000, therefore, a super-wideband audio signal is 1588// split to lower-band 0-8 kHz and upper-band 8-16 kHz. 1589// 1590// Input: 1591// - in_data : Wide band speech signal, 320 samples (10 ms) 1592// 1593// Input & Output: 1594// - filter_state1 : Filter state for first All-pass filter 1595// - filter_state2 : Filter state for second All-pass filter 1596// 1597// Output: 1598// - low_band : Lower-band signal 0-8 kHz band, 160 samples (10 ms) 1599// - high_band : Upper-band signal 8-16 kHz band (flipped in frequency 1600// domain), 160 samples (10 ms) 1601// 1602 1603// 1604// WebRtcSpl_SynthesisQMF(...) 1605// 1606// Combines the two sub bands (0-F and F-2*F Hz) into a signal of 0-2*F 1607// Hz, (current version has F = 8000 Hz). So the filter combines lower-band 1608// (0-8 kHz) and upper-band (8-16 kHz) channels to obtain super-wideband 0-16 1609// kHz audio. 1610// 1611// Input: 1612// - low_band : The signal with the 0-8 kHz band, 160 samples (10 ms) 1613// - high_band : The signal with the 8-16 kHz band, 160 samples (10 ms) 1614// 1615// Input & Output: 1616// - filter_state1 : Filter state for first All-pass filter 1617// - filter_state2 : Filter state for second All-pass filter 1618// 1619// Output: 1620// - out_data : Super-wideband speech signal, 0-16 kHz 1621// 1622 1623// int16_t WebRtcSpl_SatW32ToW16(...) 1624// 1625// This function saturates a 32-bit word into a 16-bit word. 1626// 1627// Input: 1628// - value32 : The value of a 32-bit word. 1629// 1630// Output: 1631// - out16 : the saturated 16-bit word. 1632// 1633 1634// int32_t WebRtc_MulAccumW16(...) 1635// 1636// This function multiply a 16-bit word by a 16-bit word, and accumulate this 1637// value to a 32-bit integer. 1638// 1639// Input: 1640// - a : The value of the first 16-bit word. 1641// - b : The value of the second 16-bit word. 1642// - c : The value of an 32-bit integer. 1643// 1644// Return Value: The value of a * b + c. 1645// 1646