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livetrax/libs/audiographer/audiographer/routines.h
2010-03-15 19:11:48 +00:00

70 lines
2.0 KiB
C++

#ifndef AUDIOGRAPHER_ROUTINES_H
#define AUDIOGRAPHER_ROUTINES_H
#include "types.h"
#include <cmath>
namespace AudioGrapher
{
/// Allows overriding some routines with more efficient ones.
class Routines
{
public:
typedef uint32_t uint_type;
typedef float (*compute_peak_t) (float const *, uint_type, float);
typedef void (*apply_gain_to_buffer_t) (float *, uint_type, float);
static void override_compute_peak (compute_peak_t func) { _compute_peak = func; }
static void override_apply_gain_to_buffer (apply_gain_to_buffer_t func) { _apply_gain_to_buffer = func; }
/** Computes peak in float buffer
* \n RT safe
* \param data buffer from which the peak is computed
* \param frames length of the portion of \a buffer that is checked
* \param current_peak current peak of buffer, if calculated in several passes
* \return maximum of values in [\a data, \a data + \a frames) and \a current_peak
*/
static inline float compute_peak (float const * data, uint_type frames, float current_peak)
{
return (*_compute_peak) (data, frames, current_peak);
}
/** Applies constant gain to buffer
* \n RT safe
* \param data data to which the gain is applied
* \param frames length of data
* \param gain gain that is applied
*/
static inline void apply_gain_to_buffer (float * data, uint_type frames, float gain)
{
(*_apply_gain_to_buffer) (data, frames, gain);
}
private:
static inline float default_compute_peak (float const * data, uint_type frames, float current_peak)
{
for (uint_type i = 0; i < frames; ++i) {
float abs = std::fabs(data[i]);
if (abs > current_peak) { current_peak = abs; }
}
return current_peak;
}
static inline void default_apply_gain_to_buffer (float * data, uint_type frames, float gain)
{
for (uint_type i = 0; i < frames; ++i) {
data[i] *= gain;
}
}
static compute_peak_t _compute_peak;
static apply_gain_to_buffer_t _apply_gain_to_buffer;
};
} // namespace
#endif // AUDIOGRAPHER_ROUTINES_H