patest_sine8.c

一个开源的sip源代码

/** @file patest_sine8.c
	@ingroup test_src
	@brief Test 8 bit data: play a sine wave for several seconds.
	@author Ross Bencina <[e-mail]>
*/
/*
 * $Id: patest_sine8.c 1162 2006-12-18 20:40:35Z bjornroche $
 *
 * This program uses the PortAudio Portable Audio Library.
 * For more information see: http://www.portaudio.com
 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * The text above constitutes the entire PortAudio license; however, 
 * the PortAudio community also makes the following non-binding requests:
 *
 * Any person wishing to distribute modifications to the Software is
 * requested to send the modifications to the original developer so that
 * they can be incorporated into the canonical version. It is also 
 * requested that these non-binding requests be included along with the 
 * license above.
 */

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

#define NUM_SECONDS   (8)
#define SAMPLE_RATE   (44100)
#define TABLE_SIZE    (200)
#define TEST_UNSIGNED (0)

#if TEST_UNSIGNED
#define TEST_FORMAT   paUInt8
#else
#define TEST_FORMAT   paInt8
#endif

#ifndef M_PI
#define M_PI (3.14159265)
#endif

typedef struct
{
#if TEST_UNSIGNED
    unsigned char sine[TABLE_SIZE];
#else
    char sine[TABLE_SIZE];
#endif
    int left_phase;
    int right_phase;
    unsigned int framesToGo;
}
paTestData;

/* This routine will be called by the PortAudio engine when audio is needed.
** It may called at interrupt level on some machines so don't do anything
** that could mess up the system like calling malloc() or free().
*/
static int patestCallback( const void *inputBuffer, void *outputBuffer,
                           unsigned long framesPerBuffer,
                           const PaStreamCallbackTimeInfo* timeInfo,
                           PaStreamCallbackFlags statusFlags,
                           void *userData )
{
    paTestData *data = (paTestData*)userData;
    char *out = (char*)outputBuffer;
    int i;
    int framesToCalc;
    int finished = 0;
    (void) inputBuffer; /* Prevent unused variable warnings. */

    if( data->framesToGo < framesPerBuffer )
    {
        framesToCalc = data->framesToGo;
        data->framesToGo = 0;
        finished = 1;
    }
    else
    {
        framesToCalc = framesPerBuffer;
        data->framesToGo -= framesPerBuffer;
    }

    for( i=0; i<framesToCalc; i++ )
    {
        *out++ = data->sine[data->left_phase];  /* left */
        *out++ = data->sine[data->right_phase];  /* right */
        data->left_phase += 1;
        if( data->left_phase >= TABLE_SIZE ) data->left_phase -= TABLE_SIZE;
        data->right_phase += 3; /* higher pitch so we can distinguish left and right. */
        if( data->right_phase >= TABLE_SIZE ) data->right_phase -= TABLE_SIZE;
    }
    /* zero remainder of final buffer */
    for( ; i<(int)framesPerBuffer; i++ )
    {
#if TEST_UNSIGNED
        *out++ = (unsigned char) 0x80; /* left */
        *out++ = (unsigned char) 0x80; /* right */
#else
        *out++ = 0; /* left */
        *out++ = 0; /* right */
#endif

    }
    return finished;
}

/*******************************************************************/
int main(void);
int main(void)
{
    PaStreamParameters  outputParameters;
    PaStream*           stream;
    PaError             err;
    paTestData          data;
    PaTime              streamOpened;
    int                 i, totalSamps;

#if TEST_UNSIGNED
    printf("PortAudio Test: output UNsigned 8 bit sine wave.\n");
#else
    printf("PortAudio Test: output signed 8 bit sine wave.\n");
#endif
    /* initialise sinusoidal wavetable */
    for( i=0; i<TABLE_SIZE; i++ )
    {
        data.sine[i] = (char) (127.0 * sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. ));
#if TEST_UNSIGNED
        data.sine[i] += (unsigned char) 0x80;
#endif
    }
    data.left_phase = data.right_phase = 0;
    data.framesToGo = totalSamps =  NUM_SECONDS * SAMPLE_RATE; /* Play for a few seconds. */

    err = Pa_Initialize();
    if( err != paNoError )
        goto error;

    outputParameters.device = Pa_GetDefaultOutputDevice(); /* Default output device. */
    outputParameters.channelCount = 2;                     /* Stereo output. */
    outputParameters.sampleFormat = TEST_FORMAT;
    outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
    outputParameters.hostApiSpecificStreamInfo = NULL;
    err = Pa_OpenStream( &stream,
                         NULL,      /* No input. */
                         &outputParameters,
                         SAMPLE_RATE,
                         256,       /* Frames per buffer. */
                         paClipOff, /* We won't output out of range samples so don't bother clipping them. */
                         patestCallback,
                         &data );
    if( err != paNoError )
        goto error;

    streamOpened = Pa_GetStreamTime( stream ); /* Time in seconds when stream was opened (approx). */

    err = Pa_StartStream( stream );
    if( err != paNoError )
        goto error;

    /* Watch until sound is halfway finished. */
    /* (Was ( Pa_StreamTime( stream ) < (totalSamps/2) ) in V18. */
    while( (Pa_GetStreamTime( stream ) - streamOpened) < (PaTime)NUM_SECONDS / 2.0 )
        Pa_Sleep(10);

    /* Stop sound. */
    printf("Stopping Stream.\n");
    err = Pa_StopStream( stream );
    if( err != paNoError )
        goto error;

    printf("Pause for 2 seconds.\n");
    Pa_Sleep( 2000 );

    printf("Starting again.\n");
    err = Pa_StartStream( stream );
    if( err != paNoError )
        goto error;

    printf("Waiting for sound to finish.\n");

    while( ( err = Pa_IsStreamActive( stream ) ) == 1 )
        Pa_Sleep(100);
    if( err < 0 )
        goto error;

    err = Pa_CloseStream( stream );
    if( err != paNoError )
        goto error;

    Pa_Terminate();
    printf("Test finished.\n");
    return err;
error:
    Pa_Terminate();
    fprintf( stderr, "An error occured while using the portaudio stream\n" );
    fprintf( stderr, "Error number: %d\n", err );
    fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
    return err;
}