patest_latency.c File Reference

Hear the latency caused by big buffers. Play a sine wave and change frequency based on letter input. More...

#include <stdio.h>
#include <math.h>
#include "portaudio.h"

Data Structures
struct	paTestData

Macros
#define	OUTPUT_DEVICE   (Pa_GetDefaultOutputDevice())
#define	SAMPLE_RATE   (44100)
#define	FRAMES_PER_BUFFER   (64)
#define	MIN_FREQ   (100.0f)
#define	CalcPhaseIncrement(freq)
#define	M_PI   (3.14159265)
#define	TABLE_SIZE   (400)

Functions
float	LookupSine (paTestData *data, float phase)
int	main (void)

Detailed Description

Hear the latency caused by big buffers. Play a sine wave and change frequency based on letter input.

Author

Phil Burk philb.nosp@m.urk@.nosp@m.softs.nosp@m.ynth.nosp@m..com, and Darren Gibbs

Macro Definition Documentation

CalcPhaseIncrement

#define CalcPhaseIncrement

(

freq

)

Value:

((freq)/SAMPLE_RATE)

Referenced by main().

FRAMES_PER_BUFFER

#define FRAMES_PER_BUFFER   (64)

Referenced by main().

M_PI

#define M_PI   (3.14159265)

Referenced by main().

MIN_FREQ

#define MIN_FREQ   (100.0f)

Referenced by main().

OUTPUT_DEVICE

#define OUTPUT_DEVICE   (Pa_GetDefaultOutputDevice())

Referenced by main().

SAMPLE_RATE

#define SAMPLE_RATE   (44100)

Referenced by main().

TABLE_SIZE

#define TABLE_SIZE   (400)

Referenced by LookupSine(), and main().

Function Documentation

LookupSine()

float LookupSine	(	paTestData *	data,
		float	phase )

References paTestData::sine, and TABLE_SIZE.

main()

int main

(

void

)

References CalcPhaseIncrement, PaStreamParameters::channelCount, PaDeviceInfo::defaultLowOutputLatency, PaStreamParameters::device, FRAMES_PER_BUFFER, PaStreamParameters::hostApiSpecificStreamInfo, paTestData::left_phase, M_PI, MIN_FREQ, OUTPUT_DEVICE, Pa_GetDeviceInfo(), Pa_GetErrorText(), Pa_Initialize(), Pa_OpenStream(), Pa_StartStream(), Pa_StopStream(), Pa_Terminate(), paClipOff, paDitherOff, paFloat32, paNoDevice, paNoError, paTestData::phase_increment, paTestData::right_phase, SAMPLE_RATE, PaStreamParameters::sampleFormat, paTestData::sine, PaStreamParameters::suggestedLatency, and TABLE_SIZE.