Samples: Capturing Audio to WAV File

In this example, we capture audio from the sound device and save it to WAVE file.

See also:

page_pjmedia_samples_playfile_c

This file is pjsip-apps/src/samples/recfile.c

/* $Id: recfile.c 2039 2008-06-20 22:44:47Z bennylp $ */
/* 
 * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org>
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */

#include <pjmedia.h>
#include <pjlib.h>

#include <stdio.h>

/* For logging purpose. */
#define THIS_FILE   "recfile.c"


/* Configs */
#define CLOCK_RATE          44100
#define NCHANNELS           2
#define SAMPLES_PER_FRAME   (NCHANNELS * (CLOCK_RATE * 10 / 1000))
#define BITS_PER_SAMPLE     16


static const char *desc = 
 " FILE                                     \n"
 "  recfile.c                               \n"
 "                                          \n"
 " PURPOSE:                                 \n"
 "  Record microphone to WAVE file.         \n"
 "                                          \n"
 " USAGE:                                   \n"
 "  recfile FILE.WAV                        \n"
 "";


/* Util to display the error message for the specified error code  */
static int app_perror( const char *sender, const char *title, 
                       pj_status_t status)
{
    char errmsg[PJ_ERR_MSG_SIZE];

    PJ_UNUSED_ARG(sender);

    pj_strerror(status, errmsg, sizeof(errmsg));

    printf("%s: %s [code=%d]\n", title, errmsg, status);
    return 1;
}


/*
 * main()
 */
int main(int argc, char *argv[])
{
    pj_caching_pool cp;
    pjmedia_endpt *med_endpt;
    pj_pool_t *pool;
    pjmedia_port *file_port;
    pjmedia_snd_port *snd_port;
    char tmp[10];
    pj_status_t status;


    /* Verify cmd line arguments. */
    if (argc != 2) {
        puts("");
        puts(desc);
        return 0;
    }

    /* Must init PJLIB first: */
    status = pj_init();
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, 1);

    /* Must create a pool factory before we can allocate any memory. */
    pj_caching_pool_init(&cp, &pj_pool_factory_default_policy, 0);

    /* 
     * Initialize media endpoint.
     * This will implicitly initialize PJMEDIA too.
     */
    status = pjmedia_endpt_create(&cp.factory, NULL, 1, &med_endpt);
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, 1);

    /* Create memory pool for our file player */
    pool = pj_pool_create( &cp.factory,     /* pool factory         */
                           "app",           /* pool name.           */
                           4000,            /* init size            */
                           4000,            /* increment size       */
                           NULL             /* callback on error    */
                           );

    /* Create WAVE file writer port. */
    status = pjmedia_wav_writer_port_create(  pool, argv[1],
                                              CLOCK_RATE,
                                              NCHANNELS,
                                              SAMPLES_PER_FRAME,
                                              BITS_PER_SAMPLE,
                                              0, 0, 
                                              &file_port);
    if (status != PJ_SUCCESS) {
        app_perror(THIS_FILE, "Unable to open WAV file for writing", status);
        return 1;
    }

    /* Create sound player port. */
    status = pjmedia_snd_port_create_rec( 
                 pool,                              /* pool                 */
                 -1,                                /* use default dev.     */
                 file_port->info.clock_rate,        /* clock rate.          */
                 file_port->info.channel_count,     /* # of channels.       */
                 file_port->info.samples_per_frame, /* samples per frame.   */
                 file_port->info.bits_per_sample,   /* bits per sample.     */
                 0,                                 /* options              */
                 &snd_port                          /* returned port        */
                 );
    if (status != PJ_SUCCESS) {
        app_perror(THIS_FILE, "Unable to open sound device", status);
        return 1;
    }

    /* Connect file port to the sound player.
     * Stream playing will commence immediately.
     */
    status = pjmedia_snd_port_connect( snd_port, file_port);
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, 1);



    /* 
     * Recording should be started now. 
     */


    /* Sleep to allow log messages to flush */
    pj_thread_sleep(10);


    printf("Recodring %s..\n", argv[1]);
    puts("");
    puts("Press <ENTER> to stop recording and quit");

    fgets(tmp, sizeof(tmp), stdin);

    
    /* Start deinitialization: */

    /* Destroy sound device */
    status = pjmedia_snd_port_destroy( snd_port );
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, 1);


    /* Destroy file port */
    status = pjmedia_port_destroy( file_port );
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, 1);


    /* Release application pool */
    pj_pool_release( pool );

    /* Destroy media endpoint. */
    pjmedia_endpt_destroy( med_endpt );

    /* Destroy pool factory */
    pj_caching_pool_destroy( &cp );

    /* Shutdown PJLIB */
    pj_shutdown();


    /* Done. */
    return 0;
}