modules/audio_coding/codecs/isac/main/source/structs.h

/*
 *  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.
 */

/*
 * structs.h
 *
 * This header file contains all the structs used in the ISAC codec
 *
 */

#ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_STRUCTS_H_
#define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_STRUCTS_H_

#include "modules/audio_coding/codecs/isac/bandwidth_info.h"
#include "modules/audio_coding/codecs/isac/main/source/settings.h"
#include "modules/third_party/fft/fft.h"

typedef struct Bitstreamstruct {
  uint8_t stream[STREAM_SIZE_MAX];
  uint32_t W_upper;
  uint32_t streamval;
  uint32_t stream_index;

} Bitstr;

typedef struct {
  double DataBufferLo[WINLEN];
  double DataBufferHi[WINLEN];

  double CorrBufLo[ORDERLO + 1];
  double CorrBufHi[ORDERHI + 1];

  float PreStateLoF[ORDERLO + 1];
  float PreStateLoG[ORDERLO + 1];
  float PreStateHiF[ORDERHI + 1];
  float PreStateHiG[ORDERHI + 1];
  float PostStateLoF[ORDERLO + 1];
  float PostStateLoG[ORDERLO + 1];
  float PostStateHiF[ORDERHI + 1];
  float PostStateHiG[ORDERHI + 1];

  double OldEnergy;

} MaskFiltstr;

typedef struct {
  // state vectors for each of the two analysis filters
  double INSTAT1[2 * (QORDER - 1)];
  double INSTAT2[2 * (QORDER - 1)];
  double INSTATLA1[2 * (QORDER - 1)];
  double INSTATLA2[2 * (QORDER - 1)];
  double INLABUF1[QLOOKAHEAD];
  double INLABUF2[QLOOKAHEAD];

  float INSTAT1_float[2 * (QORDER - 1)];
  float INSTAT2_float[2 * (QORDER - 1)];
  float INSTATLA1_float[2 * (QORDER - 1)];
  float INSTATLA2_float[2 * (QORDER - 1)];
  float INLABUF1_float[QLOOKAHEAD];
  float INLABUF2_float[QLOOKAHEAD];

  /* High pass filter */
  double HPstates[HPORDER];
  float HPstates_float[HPORDER];

} PreFiltBankstr;

typedef struct {
  // state vectors for each of the two analysis filters
  double STATE_0_LOWER[2 * POSTQORDER];
  double STATE_0_UPPER[2 * POSTQORDER];

  /* High pass filter */
  double HPstates1[HPORDER];
  double HPstates2[HPORDER];

  float STATE_0_LOWER_float[2 * POSTQORDER];
  float STATE_0_UPPER_float[2 * POSTQORDER];

  float HPstates1_float[HPORDER];
  float HPstates2_float[HPORDER];

} PostFiltBankstr;

typedef struct {
  // data buffer for pitch filter
  double ubuf[PITCH_BUFFSIZE];

  // low pass state vector
  double ystate[PITCH_DAMPORDER];

  // old lag and gain
  double oldlagp[1];
  double oldgainp[1];

} PitchFiltstr;

typedef struct {
  // data buffer
  double buffer[PITCH_WLPCBUFLEN];

  // state vectors
  double istate[PITCH_WLPCORDER];
  double weostate[PITCH_WLPCORDER];
  double whostate[PITCH_WLPCORDER];

  // LPC window   -> should be a global array because constant
  double window[PITCH_WLPCWINLEN];

} WeightFiltstr;

typedef struct {
  // for inital estimator
  double dec_buffer[PITCH_CORR_LEN2 + PITCH_CORR_STEP2 + PITCH_MAX_LAG / 2 -
                    PITCH_FRAME_LEN / 2 + 2];
  double decimator_state[2 * ALLPASSSECTIONS + 1];
  double hp_state[2];

  double whitened_buf[QLOOKAHEAD];

  double inbuf[QLOOKAHEAD];

  PitchFiltstr PFstr_wght;
  PitchFiltstr PFstr;
  WeightFiltstr Wghtstr;

} PitchAnalysisStruct;

/* Have instance of struct together with other iSAC structs */
typedef struct {
  /* Previous frame length (in ms)                                    */
  int32_t prev_frame_length;

  /* Previous RTP timestamp from received
     packet (in samples relative beginning)                           */
  int32_t prev_rec_rtp_number;

  /* Send timestamp for previous packet (in ms using timeGetTime())   */
  uint32_t prev_rec_send_ts;

  /* Arrival time for previous packet (in ms using timeGetTime())     */
  uint32_t prev_rec_arr_ts;

  /* rate of previous packet, derived from RTP timestamps (in bits/s) */
  float prev_rec_rtp_rate;

  /* Time sinse the last update of the BN estimate (in ms)            */
  uint32_t last_update_ts;

  /* Time sinse the last reduction (in ms)                            */
  uint32_t last_reduction_ts;

  /* How many times the estimate was update in the beginning          */
  int32_t count_tot_updates_rec;

  /* The estimated bottle neck rate from there to here (in bits/s)    */
  int32_t rec_bw;
  float rec_bw_inv;
  float rec_bw_avg;
  float rec_bw_avg_Q;

  /* The estimated mean absolute jitter value,
     as seen on this side (in ms)                                     */
  float rec_jitter;
  float rec_jitter_short_term;
  float rec_jitter_short_term_abs;
  float rec_max_delay;
  float rec_max_delay_avg_Q;

  /* (assumed) bitrate for headers (bps)                              */
  float rec_header_rate;

  /* The estimated bottle neck rate from here to there (in bits/s)    */
  float send_bw_avg;

  /* The estimated mean absolute jitter value, as seen on
     the other siee (in ms)                                           */
  float send_max_delay_avg;

  // number of packets received since last update
  int num_pkts_rec;

  int num_consec_rec_pkts_over_30k;

  // flag for marking that a high speed network has been
  // detected downstream
  int hsn_detect_rec;

  int num_consec_snt_pkts_over_30k;

  // flag for marking that a high speed network has
  // been detected upstream
  int hsn_detect_snd;

  uint32_t start_wait_period;

  int in_wait_period;

  int change_to_WB;

  uint32_t senderTimestamp;
  uint32_t receiverTimestamp;
  // enum IsacSamplingRate incomingStreamSampFreq;
  uint16_t numConsecLatePkts;
  float consecLatency;
  int16_t inWaitLatePkts;

  IsacBandwidthInfo external_bw_info;
} BwEstimatorstr;

typedef struct {
  /* boolean, flags if previous packet exceeded B.N. */
  int PrevExceed;
  /* ms */
  int ExceedAgo;
  /* packets left to send in current burst */
  int BurstCounter;
  /* packets */
  int InitCounter;
  /* ms remaining in buffer when next packet will be sent */
  double StillBuffered;

} RateModel;

/* The following strutc is used to store data from encoding, to make it
   fast and easy to construct a new bitstream with a different Bandwidth
   estimate. All values (except framelength and minBytes) is double size to
   handle 60 ms of data.
*/
typedef struct {
  /* Used to keep track of if it is first or second part of 60 msec packet */
  int startIdx;

  /* Frame length in samples */
  int16_t framelength;

  /* Pitch Gain */
  int pitchGain_index[2];

  /* Pitch Lag */
  double meanGain[2];
  int pitchIndex[PITCH_SUBFRAMES * 2];

  /* LPC */
  int LPCindex_s[108 * 2]; /* KLT_ORDER_SHAPE = 108 */
  int LPCindex_g[12 * 2];  /* KLT_ORDER_GAIN = 12 */
  double LPCcoeffs_lo[(ORDERLO + 1) * SUBFRAMES * 2];
  double LPCcoeffs_hi[(ORDERHI + 1) * SUBFRAMES * 2];

  /* Encode Spec */
  int16_t fre[FRAMESAMPLES];
  int16_t fim[FRAMESAMPLES];
  int16_t AvgPitchGain[2];

  /* Used in adaptive mode only */
  int minBytes;

} IsacSaveEncoderData;

typedef struct {
  int indexLPCShape[UB_LPC_ORDER * UB16_LPC_VEC_PER_FRAME];
  double lpcGain[SUBFRAMES << 1];
  int lpcGainIndex[SUBFRAMES << 1];

  Bitstr bitStreamObj;

  int16_t realFFT[FRAMESAMPLES_HALF];
  int16_t imagFFT[FRAMESAMPLES_HALF];
} ISACUBSaveEncDataStruct;

typedef struct {
  Bitstr bitstr_obj;
  MaskFiltstr maskfiltstr_obj;
  PreFiltBankstr prefiltbankstr_obj;
  PitchFiltstr pitchfiltstr_obj;
  PitchAnalysisStruct pitchanalysisstr_obj;
  FFTstr fftstr_obj;
  IsacSaveEncoderData SaveEnc_obj;

  int buffer_index;
  int16_t current_framesamples;

  float data_buffer_float[FRAMESAMPLES_30ms];

  int frame_nb;
  double bottleneck;
  int16_t new_framelength;
  double s2nr;

  /* Maximum allowed number of bits for a 30 msec packet */
  int16_t payloadLimitBytes30;
  /* Maximum allowed number of bits for a 30 msec packet */
  int16_t payloadLimitBytes60;
  /* Maximum allowed number of bits for both 30 and 60 msec packet */
  int16_t maxPayloadBytes;
  /* Maximum allowed rate in bytes per 30 msec packet */
  int16_t maxRateInBytes;

  /*---
    If set to 1 iSAC will not adapt the frame-size, if used in
    channel-adaptive mode. The initial value will be used for all rates.
    ---*/
  int16_t enforceFrameSize;

  /*-----
    This records the BWE index the encoder injected into the bit-stream.
    It will be used in RCU. The same BWE index of main payload will be in
    the redundant payload. We can not retrieve it from BWE because it is
    a recursive procedure (WebRtcIsac_GetDownlinkBwJitIndexImpl) and has to be
    called only once per each encode.
    -----*/
  int16_t lastBWIdx;
} ISACLBEncStruct;

typedef struct {
  Bitstr bitstr_obj;
  MaskFiltstr maskfiltstr_obj;
  PreFiltBankstr prefiltbankstr_obj;
  FFTstr fftstr_obj;
  ISACUBSaveEncDataStruct SaveEnc_obj;

  int buffer_index;
  float data_buffer_float[MAX_FRAMESAMPLES + LB_TOTAL_DELAY_SAMPLES];
  double bottleneck;
  /* Maximum allowed number of bits for a 30 msec packet */
  // int16_t        payloadLimitBytes30;
  /* Maximum allowed number of bits for both 30 and 60 msec packet */
  // int16_t        maxPayloadBytes;
  int16_t maxPayloadSizeBytes;

  double lastLPCVec[UB_LPC_ORDER];
  int16_t numBytesUsed;
  int16_t lastJitterInfo;
} ISACUBEncStruct;

typedef struct {
  Bitstr bitstr_obj;
  MaskFiltstr maskfiltstr_obj;
  PostFiltBankstr postfiltbankstr_obj;
  PitchFiltstr pitchfiltstr_obj;
  FFTstr fftstr_obj;

} ISACLBDecStruct;

typedef struct {
  Bitstr bitstr_obj;
  MaskFiltstr maskfiltstr_obj;
  PostFiltBankstr postfiltbankstr_obj;
  FFTstr fftstr_obj;

} ISACUBDecStruct;

typedef struct {
  ISACLBEncStruct ISACencLB_obj;
  ISACLBDecStruct ISACdecLB_obj;
} ISACLBStruct;

typedef struct {
  ISACUBEncStruct ISACencUB_obj;
  ISACUBDecStruct ISACdecUB_obj;
} ISACUBStruct;

/*
  This struct is used to take a snapshot of the entropy coder and LPC gains
  right before encoding LPC gains. This allows us to go back to that state
  if we like to limit the payload size.
*/
typedef struct {
  /* 6 lower-band & 6 upper-band */
  double loFiltGain[SUBFRAMES];
  double hiFiltGain[SUBFRAMES];
  /* Upper boundary of interval W */
  uint32_t W_upper;
  uint32_t streamval;
  /* Index to the current position in bytestream */
  uint32_t stream_index;
  uint8_t stream[3];
} transcode_obj;

typedef struct {
  // TODO(kwiberg): The size of these tables could be reduced by storing floats
  // instead of doubles, and by making use of the identity cos(x) =
  // sin(x+pi/2). They could also be made global constants that we fill in at
  // compile time.
  double costab1[FRAMESAMPLES_HALF];
  double sintab1[FRAMESAMPLES_HALF];
  double costab2[FRAMESAMPLES_QUARTER];
  double sintab2[FRAMESAMPLES_QUARTER];
} TransformTables;

typedef struct {
  // lower-band codec instance
  ISACLBStruct instLB;
  // upper-band codec instance
  ISACUBStruct instUB;

  // Bandwidth Estimator and model for the rate.
  BwEstimatorstr bwestimator_obj;
  RateModel rate_data_obj;
  double MaxDelay;

  /* 0 = adaptive; 1 = instantaneous */
  int16_t codingMode;

  // overall bottleneck of the codec
  int32_t bottleneck;

  // QMF Filter state
  int32_t analysisFBState1[FB_STATE_SIZE_WORD32];
  int32_t analysisFBState2[FB_STATE_SIZE_WORD32];
  int32_t synthesisFBState1[FB_STATE_SIZE_WORD32];
  int32_t synthesisFBState2[FB_STATE_SIZE_WORD32];

  // Error Code
  int16_t errorCode;

  // bandwidth of the encoded audio 8, 12 or 16 kHz
  enum ISACBandwidth bandwidthKHz;
  // Sampling rate of audio, encoder and decode,  8 or 16 kHz
  enum IsacSamplingRate encoderSamplingRateKHz;
  enum IsacSamplingRate decoderSamplingRateKHz;
  // Flag to keep track of initializations, lower & upper-band
  // encoder and decoder.
  int16_t initFlag;

  // Flag to to indicate signal bandwidth switch
  int16_t resetFlag_8kHz;

  // Maximum allowed rate, measured in Bytes per 30 ms.
  int16_t maxRateBytesPer30Ms;
  // Maximum allowed payload-size, measured in Bytes.
  int16_t maxPayloadSizeBytes;
  /* The expected sampling rate of the input signal. Valid values are 16000
   * and 32000. This is not the operation sampling rate of the codec. */
  uint16_t in_sample_rate_hz;

  // Trig tables for WebRtcIsac_Time2Spec and WebRtcIsac_Spec2time.
  TransformTables transform_tables;
} ISACMainStruct;

#endif /* MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_STRUCTS_H_ */