|
|
|
/**************************************************************************//**
|
|
|
|
* @file
|
|
|
|
* @author Steve Lascos
|
|
|
|
* @company Blackaddr Audio
|
|
|
|
*
|
|
|
|
* LibBasicFunctions is a collection of helpful functions and classes that make
|
|
|
|
* it easier to perform common tasks in Audio applications.
|
|
|
|
*
|
|
|
|
* @copyright 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 3 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, see <http://www.gnu.org/licenses/>.
|
|
|
|
*****************************************************************************/
|
|
|
|
|
|
|
|
#include <cstddef>
|
|
|
|
#include <new>
|
|
|
|
|
|
|
|
#include <arm_math.h>
|
|
|
|
#include "Arduino.h"
|
|
|
|
#include "Audio.h"
|
|
|
|
|
|
|
|
#include "BATypes.h"
|
|
|
|
#include "LibMemoryManagement.h"
|
|
|
|
|
|
|
|
#ifndef __BAGUITAR_LIBBASICFUNCTIONS_H
|
|
|
|
#define __BAGUITAR_LIBBASICFUNCTIONS_H
|
|
|
|
|
|
|
|
namespace BAGuitar {
|
|
|
|
|
|
|
|
/**************************************************************************//**
|
|
|
|
* QueuePosition is used for storing the index (in an array of queues) and the
|
|
|
|
* offset within an audio_block_t data buffer. Useful for dealing with large
|
|
|
|
* windows of audio spread across multiple audio data blocks.
|
|
|
|
*****************************************************************************/
|
|
|
|
struct QueuePosition {
|
|
|
|
int offset; ///< offset in samples within an audio_block_t data buffer
|
|
|
|
int index; ///< index in an array of audio data blocks
|
|
|
|
};
|
|
|
|
|
|
|
|
/// Calculate the exact sample position in an array of audio blocks that corresponds
|
|
|
|
/// to a particular offset given as time.
|
|
|
|
/// @param milliseconds length of the interval in milliseconds
|
|
|
|
/// @returns a struct containing the index and offset
|
|
|
|
QueuePosition calcQueuePosition(float milliseconds);
|
|
|
|
|
|
|
|
/// Calculate the exact sample position in an array of audio blocks that corresponds
|
|
|
|
/// to a particular offset given as a number of samples
|
|
|
|
/// @param milliseconds length of the interval in milliseconds
|
|
|
|
/// @returns a struct containing the index and offset
|
|
|
|
QueuePosition calcQueuePosition(size_t numSamples);
|
|
|
|
|
|
|
|
/// Calculate the number of audio samples (rounded up) that correspond to a
|
|
|
|
/// given length of time.
|
|
|
|
/// @param milliseconds length of the interval in milliseconds
|
|
|
|
/// @returns the number of corresonding audio samples.
|
|
|
|
size_t calcAudioSamples(float milliseconds);
|
|
|
|
|
|
|
|
/// Calculate a length of time in milliseconds from the number of audio samples.
|
|
|
|
/// @param numSamples Number of audio samples to convert to time
|
|
|
|
/// @return the equivalent time in milliseconds.
|
|
|
|
float calcAudioTimeMs(size_t numSamples);
|
|
|
|
|
|
|
|
/// Calculate the number of audio samples (usually an offset) from
|
|
|
|
/// a queue position.
|
|
|
|
/// @param position specifies the index and offset within a queue
|
|
|
|
/// @returns the number of samples from the start of the queue array to the
|
|
|
|
/// specified position.
|
|
|
|
size_t calcOffset(QueuePosition position);
|
|
|
|
|
|
|
|
/// Clear the contents of an audio block to zero
|
|
|
|
/// @param block pointer to the audio block to clear
|
|
|
|
void clearAudioBlock(audio_block_t *block);
|
|
|
|
|
|
|
|
/// Perform an alpha blend between to audio blocks. Performs <br>
|
|
|
|
/// out = dry*(1-mix) + wet*(mix)
|
|
|
|
/// @param out pointer to the destination audio block
|
|
|
|
/// @param dry pointer to the dry audio
|
|
|
|
/// @param wet pointer to the wet audio
|
|
|
|
/// @param mix float between 0.0 and 1.0.
|
|
|
|
void alphaBlend(audio_block_t *out, audio_block_t *dry, audio_block_t* wet, float mix);
|
|
|
|
|
|
|
|
/// Applies a gain to the audio via fixed-point scaling accoring to <br>
|
|
|
|
/// out = int * (vol * 2^coeffShift)
|
|
|
|
/// @param out pointer to output audio block
|
|
|
|
/// @param in pointer to input audio block
|
|
|
|
/// @param vol volume cofficient between -1.0 and +1.0
|
|
|
|
/// @param coeffShift number of bits to shift the coefficient
|
|
|
|
void gainAdjust(audio_block_t *out, audio_block_t *in, float vol, int coeffShift = 0);
|
|
|
|
|
|
|
|
/// Combine two audio blocks through vector addition
|
|
|
|
/// out[n] = in0[n] + in1[n]
|
|
|
|
/// @param out pointer to output audio block
|
|
|
|
/// @param in0 pointer to first input audio block to combine
|
|
|
|
/// @param in1 pointer to second input audio block to combine
|
|
|
|
void combine(audio_block_t *out, audio_block_t *in0, audio_block_t *in1);
|
|
|
|
|
|
|
|
template <class T>
|
|
|
|
class RingBuffer; // forward declare so AudioDelay can use it.
|
|
|
|
|
|
|
|
|
|
|
|
/**************************************************************************//**
|
|
|
|
* Audio delays are a very common function in audio processing. In addition to
|
|
|
|
* being used for simply create a delay effect, it can also be used for buffering
|
|
|
|
* a sliding window in time of audio samples. This is useful when combining
|
|
|
|
* several audio_block_t data buffers together to form one large buffer for
|
|
|
|
* FFTs, etc.
|
|
|
|
* @details The buffer works like a queue. You add new audio_block_t when available,
|
|
|
|
* and the class will return an old buffer when it is to be discarded from the queue.<br>
|
|
|
|
* Note that using INTERNAL memory means the class will only store a queue
|
|
|
|
* of pointers to audio_block_t buffers, since the Teensy Audio uses a shared memory
|
|
|
|
* approach. When using EXTERNAL memory, data is actually copyied to/from an external
|
|
|
|
* SRAM device.
|
|
|
|
*****************************************************************************/
|
|
|
|
constexpr size_t AUDIO_BLOCK_SIZE = sizeof(int16_t)*AUDIO_BLOCK_SAMPLES;
|
|
|
|
class AudioDelay {
|
|
|
|
public:
|
|
|
|
AudioDelay() = delete;
|
|
|
|
|
|
|
|
/// Construct an audio buffer using INTERNAL memory by specifying the max number
|
|
|
|
/// of audio samples you will want.
|
|
|
|
/// @param maxSamples equal or greater than your longest delay requirement
|
|
|
|
AudioDelay(size_t maxSamples);
|
|
|
|
|
|
|
|
/// Construct an audio buffer using INTERNAL memory by specifying the max amount of
|
|
|
|
/// time you will want available in the buffer.
|
|
|
|
/// @param maxDelayTimeMs max length of time you want in the buffer specified in milliseconds
|
|
|
|
AudioDelay(float maxDelayTimeMs);
|
|
|
|
|
|
|
|
/// Construct an audio buffer using a slot configured with the BAGuitar::ExternalSramManager
|
|
|
|
/// @param slot a pointer to the slot representing the memory you wish to use for the buffer.
|
|
|
|
AudioDelay(ExtMemSlot *slot);
|
|
|
|
|
|
|
|
~AudioDelay();
|
|
|
|
|
|
|
|
/// Add a new audio block into the buffer. When the buffer is filled,
|
|
|
|
/// adding a new block will push out the oldest once which is returned.
|
|
|
|
/// @param blockIn pointer to the most recent block of audio
|
|
|
|
/// @returns the buffer to be discarded, or nullptr if not filled (INTERNAL), or
|
|
|
|
/// not applicable (EXTERNAL).
|
|
|
|
audio_block_t *addBlock(audio_block_t *blockIn);
|
|
|
|
|
|
|
|
/// When using INTERNAL memory, returns the pointer for the specified index into buffer.
|
|
|
|
/// @details, the most recent block is 0, 2nd most recent is 1, ..., etc.
|
|
|
|
/// @param index the specifies how many buffers older than the current to retrieve
|
|
|
|
/// @returns a pointer to the requested audio_block_t
|
|
|
|
audio_block_t *getBlock(size_t index);
|
|
|
|
|
|
|
|
/// Retrieve an audio block (or samples) from the buffer.
|
|
|
|
/// @details when using INTERNAL memory, only supported size is AUDIO_BLOCK_SAMPLES. When using
|
|
|
|
/// EXTERNAL, a size smaller than AUDIO_BLOCK_SAMPLES can be requested.
|
|
|
|
/// @param dest pointer to the target audio block to write the samples to.
|
|
|
|
/// @param offsetSamples data will start being transferred offset samples from the start of the audio buffer
|
|
|
|
/// @param numSamples default value is AUDIO_BLOCK_SAMPLES, so typically you don't have to specify this parameter.
|
|
|
|
/// @returns true on success, false on error.
|
|
|
|
bool getSamples(audio_block_t *dest, size_t offsetSamples, size_t numSamples = AUDIO_BLOCK_SAMPLES);
|
|
|
|
|
|
|
|
/// When using EXTERNAL memory, this function can return a pointer to the underlying ExtMemSlot object associated
|
|
|
|
/// with the buffer.
|
|
|
|
/// @returns pointer to the underlying ExtMemSlot.
|
|
|
|
ExtMemSlot *getSlot() const { return m_slot; }
|
|
|
|
|
|
|
|
/// Ween using INTERNAL memory, thsi function can return a pointer to the underlying RingBuffer that contains
|
|
|
|
/// audio_block_t * pointers.
|
|
|
|
/// @returns pointer to the underlying RingBuffer
|
|
|
|
RingBuffer<audio_block_t*> *getRingBuffer() const { return m_ringBuffer; }
|
|
|
|
|
|
|
|
private:
|
|
|
|
|
|
|
|
/// enumerates whether the underlying memory buffer uses INTERNAL or EXTERNAL memory
|
|
|
|
enum class MemType : unsigned {
|
|
|
|
MEM_INTERNAL = 0, ///< internal audio_block_t from the Teensy Audio Library is used
|
|
|
|
MEM_EXTERNAL ///< external SPI based ram is used
|
|
|
|
};
|
|
|
|
|
|
|
|
MemType m_type; ///< when 0, INTERNAL memory, when 1, external MEMORY.
|
|
|
|
RingBuffer<audio_block_t *> *m_ringBuffer = nullptr; ///< When using INTERNAL memory, a RingBuffer will be created.
|
|
|
|
ExtMemSlot *m_slot = nullptr; ///< When using EXTERNAL memory, an ExtMemSlot must be provided.
|
|
|
|
};
|
|
|
|
|
|
|
|
/**************************************************************************//**
|
|
|
|
* IIR BiQuad Filter - Direct Form I <br>
|
|
|
|
* y[n] = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2]<br>
|
|
|
|
* Some design tools (like Matlab assume the feedback coefficients 'a' are negated. You
|
|
|
|
* may have to negate your 'a' coefficients.
|
|
|
|
* @details Note that the ARM CMSIS-DSP library requires an extra zero between first
|
|
|
|
* and second 'b' coefficients. E.g. <br>
|
|
|
|
* {b10, 0, b11, b12, a11, a12, b20, 0, b21, b22, a21, a22, ...}
|
|
|
|
*****************************************************************************/
|
|
|
|
class IirBiQuadFilter {
|
|
|
|
public:
|
|
|
|
IirBiQuadFilter() = delete;
|
|
|
|
/// Construct a Biquad filter with specified number of stages, coefficients and scaling.
|
|
|
|
/// @details See CMSIS-DSP documentation for more details
|
|
|
|
/// @param numStages number of biquad stages. Each stage has 5 coefficients.
|
|
|
|
/// @param coeffs pointer to an array of Q31 fixed-point coefficients (range -1 to +0.999...)
|
|
|
|
/// @param coeffShift coeffs are multiplied by 2^coeffShift to support coefficient range scaling
|
|
|
|
IirBiQuadFilter(unsigned numStages, const int32_t *coeffs, int coeffShift = 0);
|
|
|
|
virtual ~IirBiQuadFilter();
|
|
|
|
|
|
|
|
/// Reconfigure the filter coefficients.
|
|
|
|
/// @details See CMSIS-DSP documentation for more details
|
|
|
|
/// @param numStages number of biquad stages. Each stage has 5 coefficients.
|
|
|
|
/// @param coeffs pointer to an array of Q31 fixed-point coefficients (range -1 to +0.999...)
|
|
|
|
/// @param coeffShift coeffs are multiplied by 2^coeffShift to support coefficient range scaling
|
|
|
|
void changeFilterCoeffs(unsigned numStages, const int32_t *coeffs, int coeffShift = 0);
|
|
|
|
|
|
|
|
/// Process the data using the configured IIR filter
|
|
|
|
/// @details output and input can be the same pointer if in-place modification is desired
|
|
|
|
/// @param output pointer to where the output results will be written
|
|
|
|
/// @param input pointer to where the input data will be read from
|
|
|
|
/// @param numSampmles number of samples to process
|
|
|
|
bool process(int16_t *output, int16_t *input, size_t numSamples);
|
|
|
|
private:
|
|
|
|
const unsigned NUM_STAGES;
|
|
|
|
int32_t *m_coeffs = nullptr;
|
|
|
|
|
|
|
|
// ARM DSP Math library filter instance
|
|
|
|
arm_biquad_casd_df1_inst_q31 m_iirCfg;
|
|
|
|
int32_t *m_state = nullptr;
|
|
|
|
};
|
|
|
|
|
|
|
|
/**************************************************************************//**
|
|
|
|
* A High-precision version of IirBiQuadFilter often necessary for complex, multistage
|
|
|
|
* filters. This class uses CMSIS-DSP biquads with 64-bit internal precision instead
|
|
|
|
* of 32-bit.
|
|
|
|
*****************************************************************************/
|
|
|
|
class IirBiQuadFilterHQ {
|
|
|
|
public:
|
|
|
|
IirBiQuadFilterHQ() = delete;
|
|
|
|
/// Construct a Biquad filter with specified number of stages, coefficients and scaling.
|
|
|
|
/// @details See CMSIS-DSP documentation for more details
|
|
|
|
/// @param numStages number of biquad stages. Each stage has 5 coefficients.
|
|
|
|
/// @param coeffs pointer to an array of Q31 fixed-point coefficients (range -1 to +0.999...)
|
|
|
|
/// @param coeffShift coeffs are multiplied by 2^coeffShift to support coefficient range scaling
|
|
|
|
IirBiQuadFilterHQ(unsigned maxNumStages, const int32_t *coeffs, int coeffShift = 0);
|
|
|
|
virtual ~IirBiQuadFilterHQ();
|
|
|
|
|
|
|
|
/// Reconfigure the filter coefficients.
|
|
|
|
/// @details See CMSIS-DSP documentation for more details
|
|
|
|
/// @param numStages number of biquad stages. Each stage has 5 coefficients.
|
|
|
|
/// @param coeffs pointer to an array of Q31 fixed-point coefficients (range -1 to +0.999...)
|
|
|
|
/// @param coeffShift coeffs are multiplied by 2^coeffShift to support coefficient range scaling
|
|
|
|
void changeFilterCoeffs(unsigned numStages, const int32_t *coeffs, int coeffShift = 0);
|
|
|
|
|
|
|
|
/// Process the data using the configured IIR filter
|
|
|
|
/// @details output and input can be the same pointer if in-place modification is desired
|
|
|
|
/// @param output poinvoid combine(audio_block_t *out, audio_block_t *in0, audio_block_t *in1)ter to where the output results will be written
|
|
|
|
/// @param input pointer to where the input data will be read from
|
|
|
|
/// @param numSampmles number of samples to process
|
|
|
|
bool process(int16_t *output, int16_t *input, size_t numSamples);
|
|
|
|
private:
|
|
|
|
const unsigned NUM_STAGES;
|
|
|
|
int32_t *m_coeffs = nullptr;
|
|
|
|
|
|
|
|
// ARM DSP Math library filter instance
|
|
|
|
arm_biquad_cas_df1_32x64_ins_q31 m_iirCfg;
|
|
|
|
int64_t *m_state = nullptr;
|
|
|
|
};
|
|
|
|
|
|
|
|
/**************************************************************************//**
|
|
|
|
* A single-precision floating-point biquad using CMSIS-DSP hardware instructions.
|
|
|
|
* @details Use this when IirBiQuadFilterHQ is insufficient, since that version
|
|
|
|
* is still faster with 64-bit fixed-point arithmetic.
|
|
|
|
*****************************************************************************/
|
|
|
|
class IirBiQuadFilterFloat {
|
|
|
|
public:
|
|
|
|
IirBiQuadFilterFloat() = delete;
|
|
|
|
|
|
|
|
/// Construct a Biquad filter with specified number of stages and coefficients
|
|
|
|
/// @details See CMSIS-DSP documentation for more details
|
|
|
|
/// @param numStages number of biquad stages. Each stage has 5 coefficients.
|
|
|
|
/// @param coeffs pointer to an array of single-precision floating-point coefficients
|
|
|
|
IirBiQuadFilterFloat(unsigned maxNumStages, const float *coeffs);
|
|
|
|
virtual ~IirBiQuadFilterFloat();
|
|
|
|
|
|
|
|
/// Reconfigure the filter coefficients.
|
|
|
|
/// @details See CMSIS-DSP documentation for more details
|
|
|
|
/// @param numStages number of biquad stages. Each stage has 5 coefficients.
|
|
|
|
/// @param coeffs pointer to an array of single-precision floating-point coefficients
|
|
|
|
void changeFilterCoeffs(unsigned numStages, const float *coeffs);
|
|
|
|
|
|
|
|
/// Process the data using the configured IIR filter
|
|
|
|
/// @details output and input can be the same pointer if in-place modification is desired
|
|
|
|
/// @param output pointer to where the output results will be written
|
|
|
|
/// @param input pointer to where the input data will be read from
|
|
|
|
/// @param numberSampmles number of samples to process
|
|
|
|
bool process(float *output, float *input, size_t numSamples);
|
|
|
|
private:
|
|
|
|
const unsigned NUM_STAGES;
|
|
|
|
float *m_coeffs = nullptr;
|
|
|
|
|
|
|
|
// ARM DSP Math library filter instance
|
|
|
|
arm_biquad_cascade_df2T_instance_f32 m_iirCfg;
|
|
|
|
float *m_state = nullptr;
|
|
|
|
|
|
|
|
};
|
|
|
|
|
|
|
|
} // namespace BAGuitar
|
|
|
|
|
|
|
|
namespace BALibrary {
|
|
|
|
|
|
|
|
/**************************************************************************//**
|
|
|
|
* The class will automate a parameter using a trigger from a start value to an
|
|
|
|
* end value, using either a preprogrammed function or a user-provided LUT.
|
|
|
|
*****************************************************************************/
|
|
|
|
template <typename T>
|
|
|
|
class ParameterAutomation
|
|
|
|
{
|
|
|
|
public:
|
|
|
|
enum class Function : unsigned {
|
|
|
|
NOT_CONFIGURED = 0, ///< Initial, unconfigured stage
|
|
|
|
LINEAR, ///< f(x) = x
|
|
|
|
EXPONENTIAL, ///< f(x) = e^x
|
|
|
|
LOGARITHMIC, ///< f(x) = ln(x)
|
|
|
|
PARABOLIC, ///< f(x) = x^2
|
|
|
|
LOOKUP_TABLE ///< f(x) = lut(x)
|
|
|
|
};
|
|
|
|
ParameterAutomation();
|
|
|
|
ParameterAutomation(T startValue, T endValue, size_t durationSamples, Function function = Function::LINEAR);
|
|
|
|
ParameterAutomation(T startValue, T endValue, float durationMilliseconds, Function function = Function::LINEAR);
|
|
|
|
virtual ~ParameterAutomation();
|
|
|
|
|
|
|
|
/// set the start and end values for the automation
|
|
|
|
/// @param function select which automation curve (function) to use
|
|
|
|
/// @param startValue after reset, parameter automation start from this value
|
|
|
|
/// @param endValue after the automation duration, paramter will finish at this value
|
|
|
|
/// @param durationSamples number of samples to transition from startValue to endValue
|
|
|
|
void reconfigure(T startValue, T endValue, size_t durationSamples, Function function = Function::LINEAR);
|
|
|
|
void reconfigure(T startValue, T endValue, float durationMilliseconds, Function function = Function::LINEAR);
|
|
|
|
|
|
|
|
/// Start the automation from startValue
|
|
|
|
void trigger();
|
|
|
|
|
|
|
|
/// Retrieve the next calculated automation value
|
|
|
|
/// @returns the calculated parameter value of templated type T
|
|
|
|
T getNextValue();
|
|
|
|
|
|
|
|
bool isFinished() { return !m_running; }
|
|
|
|
|
|
|
|
private:
|
|
|
|
Function m_function;
|
|
|
|
T m_startValue;
|
|
|
|
T m_endValue;
|
|
|
|
bool m_running = false;
|
|
|
|
T m_currentValueX; ///< the current value of x in f(x)
|
|
|
|
size_t m_duration;
|
|
|
|
T m_coeffs[3]; ///< some general coefficient storage
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
// TODO: initialize with const number of sequences with null type that automatically skips
|
|
|
|
// then register each new sequence.
|
|
|
|
constexpr int MAX_PARAMETER_SEQUENCES = 32;
|
|
|
|
template <typename T>
|
|
|
|
class ParameterAutomationSequence
|
|
|
|
{
|
|
|
|
public:
|
|
|
|
ParameterAutomationSequence() = delete;
|
|
|
|
ParameterAutomationSequence(int numStages);
|
|
|
|
virtual ~ParameterAutomationSequence();
|
|
|
|
|
|
|
|
void setupParameter(int index, T startValue, T endValue, size_t durationSamples, typename ParameterAutomation<T>::Function function);
|
|
|
|
void setupParameter(int index, T startValue, T endValue, float durationMilliseconds, typename ParameterAutomation<T>::Function function);
|
|
|
|
|
|
|
|
/// Trigger a the automation sequence until numStages is reached or a Function is ParameterAutomation<T>::Function::NOT_CONFIGURED
|
|
|
|
void trigger();
|
|
|
|
|
|
|
|
T getNextValue();
|
|
|
|
bool isFinished();
|
|
|
|
|
|
|
|
private:
|
|
|
|
ParameterAutomation<T> *m_paramArray[MAX_PARAMETER_SEQUENCES];
|
|
|
|
int m_currentIndex = 0;
|
|
|
|
int m_numStages = 0;
|
|
|
|
};
|
|
|
|
|
|
|
|
} // BALibrary
|
|
|
|
|
|
|
|
|
|
|
|
#endif /* __BAGUITAR_LIBBASICFUNCTIONS_H */
|