/*---------------------------------------------------------------------------- * * File: * eas_reverbdata.h * * Contents and purpose: * Contains the prototypes for the Reverb effect. * * * Copyright Sonic Network Inc. 2006 * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * *---------------------------------------------------------------------------- * Revision Control: * $Revision: 499 $ * $Date: 2006-12-11 16:07:20 -0800 (Mon, 11 Dec 2006) $ *---------------------------------------------------------------------------- */ #ifndef _EAS_REVERBDATA_H #define _EAS_REVERBDATA_H #include "eas_types.h" #include "eas_audioconst.h" /*------------------------------------ * defines *------------------------------------ */ /* CIRCULAR() calculates the array index using modulo arithmetic. The "trick" is that modulo arithmetic is simplified by masking the effective address where the mask is (2^n)-1. This only works if the buffer size is a power of two. */ #define CIRCULAR(base,offset,size) (EAS_U32)( \ ( \ ((EAS_I32)(base)) + ((EAS_I32)(offset)) \ ) \ & size \ ) /* reverb parameters are updated every 2^(REVERB_UPDATE_PERIOD_IN_BITS) samples */ #if defined (_SAMPLE_RATE_8000) #define REVERB_UPDATE_PERIOD_IN_BITS 5 #define REVERB_BUFFER_SIZE_IN_SAMPLES 2048 #elif defined (_SAMPLE_RATE_16000) #define REVERB_UPDATE_PERIOD_IN_BITS 6 #define REVERB_BUFFER_SIZE_IN_SAMPLES 4096 #elif defined (_SAMPLE_RATE_22050) #define REVERB_UPDATE_PERIOD_IN_BITS 7 #define REVERB_BUFFER_SIZE_IN_SAMPLES 4096 #elif defined (_SAMPLE_RATE_32000) #define REVERB_UPDATE_PERIOD_IN_BITS 7 #define REVERB_BUFFER_SIZE_IN_SAMPLES 8192 #elif defined (_SAMPLE_RATE_44100) #define REVERB_UPDATE_PERIOD_IN_BITS 8 #define REVERB_BUFFER_SIZE_IN_SAMPLES 8192 #elif defined (_SAMPLE_RATE_48000) #define REVERB_UPDATE_PERIOD_IN_BITS 8 #define REVERB_BUFFER_SIZE_IN_SAMPLES 8192 #endif // Define a mask for circular addressing, so that array index // can wraparound and stay in array boundary of 0, 1, ..., (buffer size -1) // The buffer size MUST be a power of two #define REVERB_BUFFER_MASK (REVERB_BUFFER_SIZE_IN_SAMPLES -1) #define REVERB_MAX_ROOM_TYPE 4 // any room numbers larger than this are invalid #define REVERB_MAX_NUM_REFLECTIONS 5 // max num reflections per channel /* synth parameters are updated every SYNTH_UPDATE_PERIOD_IN_SAMPLES */ #define REVERB_UPDATE_PERIOD_IN_SAMPLES (EAS_I32)(0x1L << REVERB_UPDATE_PERIOD_IN_BITS) /* calculate the update counter by bitwise ANDING with this value to generate a 2^n modulo value */ #define REVERB_MODULO_UPDATE_PERIOD_IN_SAMPLES (EAS_I32)(REVERB_UPDATE_PERIOD_IN_SAMPLES -1) /* synth parameters are updated every SYNTH_UPDATE_PERIOD_IN_SECONDS seconds */ #define REVERB_UPDATE_PERIOD_IN_SECONDS (REVERB_UPDATE_PERIOD_IN_SAMPLES / _OUTPUT_SAMPLE_RATE) // xfade parameters #define REVERB_XFADE_PERIOD_IN_SECONDS (100.0 / 1000.0) // xfade once every this many seconds #define REVERB_XFADE_PERIOD_IN_SAMPLES (REVERB_XFADE_PERIOD_IN_SECONDS * _OUTPUT_SAMPLE_RATE) #define REVERB_XFADE_PHASE_INCREMENT (EAS_I16)(65536 / ((EAS_I16)REVERB_XFADE_PERIOD_IN_SAMPLES/(EAS_I16)REVERB_UPDATE_PERIOD_IN_SAMPLES)) /**********/ /* the entire synth uses various flags in a bit field */ /* if flag is set, synth reset has been requested */ #define REVERB_FLAG_RESET_IS_REQUESTED 0x01 /* bit 0 */ #define MASK_REVERB_RESET_IS_REQUESTED 0x01 #define MASK_REVERB_RESET_IS_NOT_REQUESTED (EAS_U32)(~MASK_REVERB_RESET_IS_REQUESTED) /* by default, we always want to update ALL channel parameters when we reset the synth (e.g., during GM ON) */ #define DEFAULT_REVERB_FLAGS 0x0 /* coefficients for generating sin, cos */ #define REVERB_PAN_G2 4294940151 /* -0.82842712474619 = 2 - 4/sqrt(2) */ /* EAS_I32 nPanG1 = +1.0 for sin EAS_I32 nPanG1 = -1.0 for cos */ #define REVERB_PAN_G0 23170 /* 0.707106781186547 = 1/sqrt(2) */ /*************************************************************/ // define the input injection points #define GUARD 5 // safety guard of this many samples #define MAX_AP_TIME (double) (20.0/1000.0) // delay time in milliseconds #define MAX_DELAY_TIME (double) (65.0/1000.0) // delay time in milliseconds #define MAX_AP_SAMPLES (int)(((double) MAX_AP_TIME) * ((double) _OUTPUT_SAMPLE_RATE)) #define MAX_DELAY_SAMPLES (int)(((double) MAX_DELAY_TIME) * ((double) _OUTPUT_SAMPLE_RATE)) #define AP0_IN 0 #define AP1_IN (AP0_IN + MAX_AP_SAMPLES + GUARD) #define DELAY0_IN (AP1_IN + MAX_AP_SAMPLES + GUARD) #define DELAY1_IN (DELAY0_IN + MAX_DELAY_SAMPLES + GUARD) // Define the max offsets for the end points of each section // i.e., we don't expect a given section's taps to go beyond // the following limits #define AP0_OUT (AP0_IN + MAX_AP_SAMPLES -1) #define AP1_OUT (AP1_IN + MAX_AP_SAMPLES -1) #define DELAY0_OUT (DELAY0_IN + MAX_DELAY_SAMPLES -1) #define DELAY1_OUT (DELAY1_IN + MAX_DELAY_SAMPLES -1) #define REVERB_DEFAULT_ROOM_NUMBER 1 // default preset number #define DEFAULT_AP0_LENGTH (int)(((double) (17.0/1000.0)) * ((double) _OUTPUT_SAMPLE_RATE)) #define DEFAULT_AP0_GAIN 19400 #define DEFAULT_AP1_LENGTH (int)(((double) (16.5/1000.0)) * ((double) _OUTPUT_SAMPLE_RATE)) #define DEFAULT_AP1_GAIN -19400 #define REVERB_DEFAULT_WET 32767 #define REVERB_DEFAULT_DRY 0 #define EAS_REVERB_WET_MAX 32767 #define EAS_REVERB_WET_MIN 0 #define EAS_REVERB_DRY_MAX 32767 #define EAS_REVERB_DRY_MIN 0 /* parameters for each allpass */ typedef struct { EAS_U16 m_zApOut; // delay offset for ap out EAS_I16 m_nApGain; // gain for ap EAS_U16 m_zApIn; // delay offset for ap in } S_ALLPASS_OBJECT; /* parameters for each allpass */ typedef struct { EAS_PCM m_zLpf; // actual state variable, not a length EAS_I16 m_nLpfFwd; // lpf forward gain EAS_I16 m_nLpfFbk; // lpf feedback gain EAS_U16 m_zDelay[REVERB_MAX_NUM_REFLECTIONS]; // delay offset for ap out EAS_I16 m_nGain[REVERB_MAX_NUM_REFLECTIONS]; // gain for ap } S_EARLY_REFLECTION_OBJECT; //demo typedef struct { EAS_I16 m_nLpfFbk; EAS_I16 m_nLpfFwd; EAS_I16 m_nEarly; EAS_I16 m_nWet; EAS_I16 m_nDry; EAS_I16 m_nEarlyL_LpfFbk; EAS_I16 m_nEarlyL_LpfFwd; EAS_I16 m_nEarlyL_Delay0; //8 EAS_I16 m_nEarlyL_Gain0; EAS_I16 m_nEarlyL_Delay1; EAS_I16 m_nEarlyL_Gain1; EAS_I16 m_nEarlyL_Delay2; EAS_I16 m_nEarlyL_Gain2; EAS_I16 m_nEarlyL_Delay3; EAS_I16 m_nEarlyL_Gain3; EAS_I16 m_nEarlyL_Delay4; EAS_I16 m_nEarlyL_Gain4; EAS_I16 m_nEarlyR_Delay0; //18 EAS_I16 m_nEarlyR_Gain0; EAS_I16 m_nEarlyR_Delay1; EAS_I16 m_nEarlyR_Gain1; EAS_I16 m_nEarlyR_Delay2; EAS_I16 m_nEarlyR_Gain2; EAS_I16 m_nEarlyR_Delay3; EAS_I16 m_nEarlyR_Gain3; EAS_I16 m_nEarlyR_Delay4; EAS_I16 m_nEarlyR_Gain4; EAS_U16 m_nMaxExcursion; //28 EAS_I16 m_nXfadeInterval; EAS_I16 m_nAp0_ApGain; //30 EAS_I16 m_nAp0_ApOut; EAS_I16 m_nAp1_ApGain; EAS_I16 m_nAp1_ApOut; EAS_I16 m_rfu4; EAS_I16 m_rfu5; EAS_I16 m_rfu6; EAS_I16 m_rfu7; EAS_I16 m_rfu8; EAS_I16 m_rfu9; EAS_I16 m_rfu10; //43 } S_REVERB_PRESET; typedef struct { S_REVERB_PRESET m_sPreset[REVERB_MAX_ROOM_TYPE]; //array of presets } S_REVERB_PRESET_BANK; /* parameters for each reverb */ typedef struct { /* controls entire reverb playback volume */ /* to conserve memory, use the MSB and ignore the LSB */ EAS_U8 m_nMasterVolume; /* update counter keeps track of when synth params need updating */ /* only needs to be as large as REVERB_UPDATE_PERIOD_IN_SAMPLES */ EAS_I16 m_nUpdateCounter; EAS_U16 m_nMinSamplesToAdd; /* ComputeReverb() generates this many samples */ EAS_U8 m_nFlags; /* misc flags/bit fields */ EAS_PCM *m_pOutputBuffer; EAS_PCM *m_pInputBuffer; EAS_U16 m_nNumSamplesInOutputBuffer; EAS_U16 m_nNumSamplesInInputBuffer; EAS_U16 m_nNumInputSamplesRead; // if m_nNumInputSamplesRead >= NumSamplesInInputBuffer // then get a new input buffer EAS_PCM *m_pNextInputSample; EAS_U16 m_nBaseIndex; // base index for circular buffer // reverb delay line offsets, allpass parameters, etc: EAS_PCM m_nRevOutFbkR; // combine feedback reverb right out with dry left in S_ALLPASS_OBJECT m_sAp0; // allpass 0 (left channel) EAS_U16 m_zD0In; // delay offset for delay line D0 in EAS_PCM m_nRevOutFbkL; // combine feedback reverb left out with dry right in S_ALLPASS_OBJECT m_sAp1; // allpass 1 (right channel) EAS_U16 m_zD1In; // delay offset for delay line D1 in // delay output taps, notice criss cross order EAS_U16 m_zD0Self; // self feeds forward d0 --> d0 EAS_U16 m_zD1Cross; // cross feeds across d1 --> d0 EAS_PCM m_zLpf0; // actual state variable, not a length EAS_U16 m_zD1Self; // self feeds forward d1 --> d1 EAS_U16 m_zD0Cross; // cross feeds across d0 --> d1 EAS_PCM m_zLpf1; // actual state variable, not a length EAS_I16 m_nSin; // gain for self taps EAS_I16 m_nCos; // gain for cross taps EAS_I16 m_nSinIncrement; // increment for gain EAS_I16 m_nCosIncrement; // increment for gain EAS_I16 m_nLpfFwd; // lpf forward gain (includes scaling for mixer) EAS_I16 m_nLpfFbk; // lpf feedback gain EAS_U16 m_nXfadeInterval; // update/xfade after this many samples EAS_U16 m_nXfadeCounter; // keep track of when to xfade EAS_I16 m_nPhase; // -1 <= m_nPhase < 1 // but during sin,cos calculations // use m_nPhase/2 EAS_I16 m_nPhaseIncrement; // add this to m_nPhase each frame EAS_I16 m_nNoise; // random noise sample EAS_U16 m_nMaxExcursion; // the taps can excurse +/- this amount EAS_BOOL m_bUseNoise; // if EAS_TRUE, use noise as input signal EAS_BOOL m_bBypass; // if EAS_TRUE, then bypass reverb and copy input to output EAS_I16 m_nCurrentRoom; // preset number for current room EAS_I16 m_nNextRoom; // preset number for next room EAS_I16 m_nWet; // gain for wet (processed) signal EAS_I16 m_nDry; // gain for dry (unprocessed) signal EAS_I16 m_nEarly; // gain for early (widen) signal S_EARLY_REFLECTION_OBJECT m_sEarlyL; // left channel early reflections S_EARLY_REFLECTION_OBJECT m_sEarlyR; // right channel early reflections EAS_PCM m_nDelayLine[REVERB_BUFFER_SIZE_IN_SAMPLES]; // one large delay line for all reverb elements S_REVERB_PRESET pPreset; S_REVERB_PRESET_BANK m_sPreset; //EAS_I8 preset; } S_REVERB_OBJECT; /*------------------------------------ * prototypes *------------------------------------ */ /*---------------------------------------------------------------------------- * ReverbUpdateXfade *---------------------------------------------------------------------------- * Purpose: * Update the xfade parameters as required * * Inputs: * nNumSamplesToAdd - number of samples to write to buffer * * Outputs: * * * Side Effects: * - xfade parameters will be changed * *---------------------------------------------------------------------------- */ static EAS_RESULT ReverbUpdateXfade(S_REVERB_OBJECT* pReverbData, EAS_INT nNumSamplesToAdd); /*---------------------------------------------------------------------------- * ReverbCalculateNoise *---------------------------------------------------------------------------- * Purpose: * Calculate a noise sample and limit its value * * Inputs: * nMaxExcursion - noise value is limited to this value * pnNoise - return new noise sample in this (not limited) * * Outputs: * new limited noise value * * Side Effects: * - *pnNoise noise value is updated * *---------------------------------------------------------------------------- */ static EAS_U16 ReverbCalculateNoise(EAS_U16 nMaxExcursion, EAS_I16 *pnNoise); /*---------------------------------------------------------------------------- * ReverbCalculateSinCos *---------------------------------------------------------------------------- * Purpose: * Calculate a new sin and cosine value based on the given phase * * Inputs: * nPhase - phase angle * pnSin - input old value, output new value * pnCos - input old value, output new value * * Outputs: * * Side Effects: * - *pnSin, *pnCos are updated * *---------------------------------------------------------------------------- */ static EAS_RESULT ReverbCalculateSinCos(EAS_I16 nPhase, EAS_I16 *pnSin, EAS_I16 *pnCos); /*---------------------------------------------------------------------------- * Reverb *---------------------------------------------------------------------------- * Purpose: * apply reverb to the given signal * * Inputs: * nNu * pnSin - input old value, output new value * pnCos - input old value, output new value * * Outputs: * number of samples actually reverberated * * Side Effects: * *---------------------------------------------------------------------------- */ static EAS_RESULT Reverb(S_REVERB_OBJECT* pReverbData, EAS_INT nNumSamplesToAdd, EAS_PCM *pOutputBuffer, EAS_PCM *pInputBuffer); /*---------------------------------------------------------------------------- * ReverbReadInPresets() *---------------------------------------------------------------------------- * Purpose: sets global reverb preset bank to defaults * * Inputs: * * Outputs: * *---------------------------------------------------------------------------- */ static EAS_RESULT ReverbReadInPresets(S_REVERB_OBJECT* pReverbData); /*---------------------------------------------------------------------------- * ReverbUpdateRoom *---------------------------------------------------------------------------- * Purpose: * Update the room's preset parameters as required * * Inputs: * * Outputs: * * * Side Effects: * - reverb paramters (fbk, fwd, etc) will be changed * - m_nCurrentRoom := m_nNextRoom *---------------------------------------------------------------------------- */ static EAS_RESULT ReverbUpdateRoom(S_REVERB_OBJECT* pReverbData); #endif /* #ifndef _EAS_REVERBDATA_H */