JackFilters.h
/*
Copyright (C) 2008 Grame
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef __JackFilters__
#define __JackFilters__
#ifdef __APPLE__
#include <TargetConditionals.h>
#endif
#include "jack.h"
#ifndef MY_TARGET_OS_IPHONE
#include "JackAtomicState.h"
#endif
#include <math.h>
#include <stdlib.h>
namespace Jack
{
#ifndef TARGET_OS_IPHONE
#define MAX_SIZE 64
PRE_PACKED_STRUCTURE
struct JackFilter
{
jack_time_t fTable[MAX_SIZE];
JackFilter()
{
for (int i = 0; i < MAX_SIZE; i++) {
fTable[i] = 0;
}
}
void AddValue(jack_time_t val)
{
memcpy(&fTable[1], &fTable[0], sizeof(jack_time_t) * (MAX_SIZE - 1));
fTable[0] = val;
}
jack_time_t GetVal()
{
jack_time_t mean = 0;
for (int i = 0; i < MAX_SIZE; i++) {
mean += fTable[i];
}
return mean / MAX_SIZE;
}
} POST_PACKED_STRUCTURE;
PRE_PACKED_STRUCTURE
class JackDelayLockedLoop
{
private:
jack_nframes_t fFrames;
jack_time_t fCurrentWakeup;
jack_time_t fCurrentCallback;
jack_time_t fNextWakeUp;
float fSecondOrderIntegrator;
jack_nframes_t fBufferSize;
jack_nframes_t fSampleRate;
jack_time_t fPeriodUsecs;
float fFilterCoefficient; /* set once, never altered */
bool fUpdating;
public:
JackDelayLockedLoop()
{}
JackDelayLockedLoop(jack_nframes_t buffer_size, jack_nframes_t sample_rate)
{
Init(buffer_size, sample_rate);
}
void Init(jack_nframes_t buffer_size, jack_nframes_t sample_rate)
{
fFrames = 0;
fCurrentWakeup = 0;
fCurrentCallback = 0;
fNextWakeUp = 0;
fFilterCoefficient = 0.01f;
fSecondOrderIntegrator = 0.0f;
fBufferSize = buffer_size;
fSampleRate = sample_rate;
fPeriodUsecs = jack_time_t(1000000.f / fSampleRate * fBufferSize); // in microsec
}
void Init(jack_time_t callback_usecs)
{
fFrames = 0;
fCurrentWakeup = 0;
fSecondOrderIntegrator = 0.0f;
fCurrentCallback = callback_usecs;
fNextWakeUp = callback_usecs + fPeriodUsecs;
}
void IncFrame(jack_time_t callback_usecs)
{
float delta = (int64_t)callback_usecs - (int64_t)fNextWakeUp;
fCurrentWakeup = fNextWakeUp;
fCurrentCallback = callback_usecs;
fFrames += fBufferSize;
fSecondOrderIntegrator += 0.5f * fFilterCoefficient * delta;
fNextWakeUp = fCurrentWakeup + fPeriodUsecs + (int64_t) floorf((fFilterCoefficient * (delta + fSecondOrderIntegrator)));
}
jack_nframes_t Time2Frames(jack_time_t time)
{
long delta = (long) rint(((double) ((long long)(time - fCurrentWakeup)) / ((long long)(fNextWakeUp - fCurrentWakeup))) * fBufferSize);
return (delta < 0) ? ((fFrames > 0) ? fFrames : 1) : (fFrames + delta);
}
jack_time_t Frames2Time(jack_nframes_t frames)
{
long delta = (long) rint(((double) ((long long)(frames - fFrames)) * ((long long)(fNextWakeUp - fCurrentWakeup))) / fBufferSize);
return (delta < 0) ? ((fCurrentWakeup > 0) ? fCurrentWakeup : 1) : (fCurrentWakeup + delta);
}
jack_nframes_t CurFrame()
{
return fFrames;
}
jack_time_t CurTime()
{
return fCurrentWakeup;
}
} POST_PACKED_STRUCTURE;
PRE_PACKED_STRUCTURE
class JackAtomicDelayLockedLoop : public JackAtomicState<JackDelayLockedLoop>
{
public:
JackAtomicDelayLockedLoop(jack_nframes_t buffer_size, jack_nframes_t sample_rate)
{
fState[0].Init(buffer_size, sample_rate);
fState[1].Init(buffer_size, sample_rate);
}
void Init(jack_time_t callback_usecs)
{
JackDelayLockedLoop* dll = WriteNextStateStart();
dll->Init(callback_usecs);
WriteNextStateStop();
TrySwitchState(); // always succeed since there is only one writer
}
void Init(jack_nframes_t buffer_size, jack_nframes_t sample_rate)
{
JackDelayLockedLoop* dll = WriteNextStateStart();
dll->Init(buffer_size, sample_rate);
WriteNextStateStop();
TrySwitchState(); // always succeed since there is only one writer
}
void IncFrame(jack_time_t callback_usecs)
{
JackDelayLockedLoop* dll = WriteNextStateStart();
dll->IncFrame(callback_usecs);
WriteNextStateStop();
TrySwitchState(); // always succeed since there is only one writer
}
jack_nframes_t Time2Frames(jack_time_t time)
{
UInt16 next_index = GetCurrentIndex();
UInt16 cur_index;
jack_nframes_t res;
do {
cur_index = next_index;
res = ReadCurrentState()->Time2Frames(time);
next_index = GetCurrentIndex();
} while (cur_index != next_index); // Until a coherent state has been read
return res;
}
jack_time_t Frames2Time(jack_nframes_t frames)
{
UInt16 next_index = GetCurrentIndex();
UInt16 cur_index;
jack_time_t res;
do {
cur_index = next_index;
res = ReadCurrentState()->Frames2Time(frames);
next_index = GetCurrentIndex();
} while (cur_index != next_index); // Until a coherent state has been read
return res;
}
} POST_PACKED_STRUCTURE;
#endif
/*
Torben Hohn PI controler from JACK1
*/
struct JackPIControler {
double resample_mean;
double static_resample_factor;
double* offset_array;
double* window_array;
int offset_differential_index;
double offset_integral;
double catch_factor;
double catch_factor2;
double pclamp;
double controlquant;
int smooth_size;
double hann(double x)
{
return 0.5 * (1.0 - cos(2 * M_PI * x));
}
JackPIControler(double resample_factor, int fir_size)
{
resample_mean = resample_factor;
static_resample_factor = resample_factor;
offset_array = new double[fir_size];
window_array = new double[fir_size];
offset_differential_index = 0;
offset_integral = 0.0;
smooth_size = fir_size;
for (int i = 0; i < fir_size; i++) {
offset_array[i] = 0.0;
window_array[i] = hann(double(i) / (double(fir_size) - 1.0));
}
// These values could be configurable
catch_factor = 100000;
catch_factor2 = 10000;
pclamp = 15.0;
controlquant = 10000.0;
}
~JackPIControler()
{
delete[] offset_array;
delete[] window_array;
}
void Init(double resample_factor)
{
resample_mean = resample_factor;
static_resample_factor = resample_factor;
}
/*
double GetRatio(int fill_level)
{
double offset = fill_level;
// Save offset.
offset_array[(offset_differential_index++) % smooth_size] = offset;
// Build the mean of the windowed offset array basically fir lowpassing.
double smooth_offset = 0.0;
for (int i = 0; i < smooth_size; i++) {
smooth_offset += offset_array[(i + offset_differential_index - 1) % smooth_size] * window_array[i];
}
smooth_offset /= double(smooth_size);
// This is the integral of the smoothed_offset
offset_integral += smooth_offset;
// Clamp offset : the smooth offset still contains unwanted noise which would go straigth onto the resample coeff.
// It only used in the P component and the I component is used for the fine tuning anyways.
if (fabs(smooth_offset) < pclamp)
smooth_offset = 0.0;
// Ok, now this is the PI controller.
// u(t) = K * (e(t) + 1/T \int e(t') dt')
// Kp = 1/catch_factor and T = catch_factor2 Ki = Kp/T
double current_resample_factor
= static_resample_factor - smooth_offset / catch_factor - offset_integral / catch_factor / catch_factor2;
// Now quantize this value around resample_mean, so that the noise which is in the integral component doesnt hurt.
current_resample_factor = floor((current_resample_factor - resample_mean) * controlquant + 0.5) / controlquant + resample_mean;
// Calculate resample_mean so we can init ourselves to saner values.
resample_mean = 0.9999 * resample_mean + 0.0001 * current_resample_factor;
return current_resample_factor;
}
*/
double GetRatio(int error)
{
double smooth_offset = error;
// This is the integral of the smoothed_offset
offset_integral += smooth_offset;
// Ok, now this is the PI controller.
// u(t) = K * (e(t) + 1/T \int e(t') dt')
// Kp = 1/catch_factor and T = catch_factor2 Ki = Kp/T
return static_resample_factor - smooth_offset/catch_factor - offset_integral/catch_factor/catch_factor2;
}
void OurOfBounds()
{
int i;
// Set the resample_rate... we need to adjust the offset integral, to do this.
// first look at the PI controller, this code is just a special case, which should never execute once
// everything is swung in.
offset_integral = - (resample_mean - static_resample_factor) * catch_factor * catch_factor2;
// Also clear the array. we are beginning a new control cycle.
for (i = 0; i < smooth_size; i++) {
offset_array[i] = 0.0;
}
}
};
}
#endif
Jack::JackAtomicState< JackDelayLockedLoop >::ReadCurrentState
JackDelayLockedLoop * ReadCurrentState()
Returns the current state : only valid in the RT reader thread.
Definition: JackAtomicState.h:144
Jack::JackAtomicDelayLockedLoop
Definition: JackFilters.h:155
Jack::JackDelayLockedLoop
Definition: JackFilters.h:72
Jack::JackPIControler
Definition: JackFilters.h:226
Jack
Definition: JackAC3Encoder.cpp:30
Jack::JackAtomicState< JackDelayLockedLoop >::WriteNextStateStop
void WriteNextStateStop()
Stop write operation : make the next state ready to be used by the RT thread.
Definition: JackAtomicState.h:202
Jack::JackAtomicState< JackDelayLockedLoop >::WriteNextStateStart
JackDelayLockedLoop * WriteNextStateStart()
Start write operation : setup and returns the next state to update, check for recursive write calls...
Definition: JackAtomicState.h:191
Jack::JackFilter
Definition: JackFilters.h:42
Jack::JackAtomicState< JackDelayLockedLoop >::GetCurrentIndex
UInt16 GetCurrentIndex()
Returns the current state index.
Definition: JackAtomicState.h:152
Jack::JackAtomicState< JackDelayLockedLoop >::TrySwitchState
JackDelayLockedLoop * TrySwitchState()
Tries to switch to the next state and returns the new current state (either the same as before if cas...
Definition: JackAtomicState.h:160
Jack::JackAtomicState
A class to handle two states (switching from one to the other) in a lock-free manner.
Definition: JackAtomicState.h:90