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      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  * Specifies the interface for the AEC core.
     13  */
     14 
     15 #ifndef WEBRTC_MODULES_AUDIO_PROCESSING_AEC_AEC_CORE_H_
     16 #define WEBRTC_MODULES_AUDIO_PROCESSING_AEC_AEC_CORE_H_
     17 
     18 #include "webrtc/typedefs.h"
     19 
     20 #define FRAME_LEN 80
     21 #define PART_LEN 64               // Length of partition
     22 #define PART_LEN1 (PART_LEN + 1)  // Unique fft coefficients
     23 #define PART_LEN2 (PART_LEN * 2)  // Length of partition * 2
     24 
     25 typedef float complex_t[2];
     26 // For performance reasons, some arrays of complex numbers are replaced by twice
     27 // as long arrays of float, all the real parts followed by all the imaginary
     28 // ones (complex_t[SIZE] -> float[2][SIZE]). This allows SIMD optimizations and
     29 // is better than two arrays (one for the real parts and one for the imaginary
     30 // parts) as this other way would require two pointers instead of one and cause
     31 // extra register spilling. This also allows the offsets to be calculated at
     32 // compile time.
     33 
     34 // Metrics
     35 enum {
     36   kOffsetLevel = -100
     37 };
     38 
     39 typedef struct Stats {
     40   float instant;
     41   float average;
     42   float min;
     43   float max;
     44   float sum;
     45   float hisum;
     46   float himean;
     47   int counter;
     48   int hicounter;
     49 } Stats;
     50 
     51 typedef struct AecCore AecCore;
     52 
     53 int WebRtcAec_CreateAec(AecCore** aec);
     54 int WebRtcAec_FreeAec(AecCore* aec);
     55 int WebRtcAec_InitAec(AecCore* aec, int sampFreq);
     56 void WebRtcAec_InitAec_SSE2(void);
     57 #if defined(MIPS_FPU_LE)
     58 void WebRtcAec_InitAec_mips(void);
     59 #endif
     60 #if defined(WEBRTC_DETECT_ARM_NEON) || defined(WEBRTC_ARCH_ARM_NEON)
     61 void WebRtcAec_InitAec_neon(void);
     62 #endif
     63 
     64 void WebRtcAec_BufferFarendPartition(AecCore* aec, const float* farend);
     65 void WebRtcAec_ProcessFrame(AecCore* aec,
     66                             const float* nearend,
     67                             const float* nearendH,
     68                             int knownDelay,
     69                             float* out,
     70                             float* outH);
     71 
     72 // A helper function to call WebRtc_MoveReadPtr() for all far-end buffers.
     73 // Returns the number of elements moved, and adjusts |system_delay| by the
     74 // corresponding amount in ms.
     75 int WebRtcAec_MoveFarReadPtr(AecCore* aec, int elements);
     76 
     77 // Calculates the median and standard deviation among the delay estimates
     78 // collected since the last call to this function.
     79 int WebRtcAec_GetDelayMetricsCore(AecCore* self, int* median, int* std);
     80 
     81 // Returns the echo state (1: echo, 0: no echo).
     82 int WebRtcAec_echo_state(AecCore* self);
     83 
     84 // Gets statistics of the echo metrics ERL, ERLE, A_NLP.
     85 void WebRtcAec_GetEchoStats(AecCore* self,
     86                             Stats* erl,
     87                             Stats* erle,
     88                             Stats* a_nlp);
     89 #ifdef WEBRTC_AEC_DEBUG_DUMP
     90 void* WebRtcAec_far_time_buf(AecCore* self);
     91 #endif
     92 
     93 // Sets local configuration modes.
     94 void WebRtcAec_SetConfigCore(AecCore* self,
     95                              int nlp_mode,
     96                              int metrics_mode,
     97                              int delay_logging);
     98 
     99 // Non-zero enables, zero disables.
    100 void WebRtcAec_enable_reported_delay(AecCore* self, int enable);
    101 
    102 // Returns non-zero if reported delay is enabled and zero if disabled.
    103 int WebRtcAec_reported_delay_enabled(AecCore* self);
    104 
    105 // We now interpret delay correction to mean an extended filter length feature.
    106 // We reuse the delay correction infrastructure to avoid changes through to
    107 // libjingle. See details along with |DelayCorrection| in
    108 // echo_cancellation_impl.h. Non-zero enables, zero disables.
    109 void WebRtcAec_enable_delay_correction(AecCore* self, int enable);
    110 
    111 // Returns non-zero if delay correction is enabled and zero if disabled.
    112 int WebRtcAec_delay_correction_enabled(AecCore* self);
    113 
    114 // Returns the current |system_delay|, i.e., the buffered difference between
    115 // far-end and near-end.
    116 int WebRtcAec_system_delay(AecCore* self);
    117 
    118 // Sets the |system_delay| to |value|.  Note that if the value is changed
    119 // improperly, there can be a performance regression.  So it should be used with
    120 // care.
    121 void WebRtcAec_SetSystemDelay(AecCore* self, int delay);
    122 
    123 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_AEC_AEC_CORE_H_
    124