ptime = test_data->samples_per_frame * 1000000 /	    test_data->clock_rate;    /* Calculate jitter */    min_jitter = 0xFFFFF;    max_jitter = 0;    sum_jitter = 0;    for (i=1; i<strm_data->counter; ++i) {	int jitter1, jitter2, jitter;	/* jitter1 is interarrival difference */	jitter1 = strm_data->delay[i] - strm_data->delay[i-1];	if (jitter1 < 0) jitter1 = -jitter1;		/* jitter2 is difference between actual and scheduled arrival.	 * This is intended to capture situation when frames are coming	 * instantaneously, which will calculate as zero jitter with	 * jitter1 calculation.	 */	jitter2 = ptime - strm_data->delay[i];	if (jitter2 < 0) jitter2 = -jitter2;	/* Set jitter as the maximum of the two jitter calculations. 	 * This is intended to show the worst result.	 */	jitter = (jitter1>jitter2) ? jitter1 : jitter2;	/* Calculate min, max, avg jitter */	if (jitter < (int)min_jitter) min_jitter = jitter;	if (jitter > (int)max_jitter) max_jitter = jitter;	sum_jitter += jitter;    }    avg_jitter = (sum_jitter) / (strm_data->counter - 1);    if (max_jitter < WARN_JITTER_USEC) {	PJ_LOG(3,(THIS_FILE, 		  "   Jitter: min=%d.%03dms, avg=%d.%03dms, max=%d.%03dms",		  min_jitter/1000, min_jitter%1000, 		  avg_jitter/1000, avg_jitter%1000,		  max_jitter/1000, max_jitter%1000));    } else {	test_data->has_error = 1;	PJ_LOG(2,(THIS_FILE, 		  "   Jitter: min=%d.%03dms, avg=%d.%03dms, max=%d.%03dms",		  min_jitter/1000, min_jitter%1000, 		  avg_jitter/1000, avg_jitter%1000,		  max_jitter/1000, max_jitter%1000));    }}static int perform_test(int dev_id, pjmedia_dir dir,		        unsigned clock_rate, unsigned samples_per_frame, 			unsigned nchannel, int verbose){    pj_status_t status = PJ_SUCCESS;    pjmedia_snd_stream *strm;    struct test_data test_data;    pjmedia_snd_stream_info si;    /*     * Init test parameters     */    pj_bzero(&test_data, sizeof(test_data));    test_data.dir = dir;    test_data.clock_rate = clock_rate;    test_data.samples_per_frame = samples_per_frame;    test_data.channel_count = nchannel;    /*     * Open device.     */    if (dir == PJMEDIA_DIR_CAPTURE) {	status = pjmedia_snd_open_rec( dev_id, clock_rate, nchannel,				       samples_per_frame, 16, &rec_cb, 				       &test_data, &strm);    } else if (dir == PJMEDIA_DIR_PLAYBACK) {	status = pjmedia_snd_open_player( dev_id, clock_rate, nchannel,					  samples_per_frame, 16, &play_cb, 					  &test_data, &strm);    } else {	status = pjmedia_snd_open( dev_id, dev_id, clock_rate, nchannel,				   samples_per_frame, 16, &rec_cb, &play_cb, 				   &test_data, &strm);    }        if (status != PJ_SUCCESS) {        app_perror("Unable to open device for capture", status);        return status;    }    pjmedia_snd_stream_get_info(strm, &si);    if (si.play_id >= 0) {	PJ_LOG(3,(THIS_FILE, "Testing playback device %s", 		  pjmedia_snd_get_dev_info(si.play_id)->name));    }    if (si.rec_id >= 0) {	PJ_LOG(3,(THIS_FILE, "Testing capture device %s", 		  pjmedia_snd_get_dev_info(si.rec_id)->name));    }    /* Sleep for a while to let sound device "settles" */    pj_thread_sleep(200);    /*     * Start the stream.     */    status = pjmedia_snd_stream_start(strm);    if (status != PJ_SUCCESS) {        app_perror("Unable to start capture stream", status);        return status;    }    PJ_LOG(3,(THIS_FILE,	      " Please wait while test is in progress (~%d secs)..",	      (DURATION+SKIP_DURATION)/1000));    /* Let the stream runs for few msec/sec to get stable result.     * (capture normally begins with frames available simultaneously).     */    pj_thread_sleep(SKIP_DURATION);    /* Begin gather data */    test_data.running = 1;    /*      * Let the test runs for a while.     */    pj_thread_sleep(DURATION);    /*     * Close stream.     */    test_data.running = 0;    pjmedia_snd_stream_close(strm);    /*      * Print results.     */    PJ_LOG(3,(THIS_FILE, " Dumping results:"));    PJ_LOG(3,(THIS_FILE, "  Parameters: clock rate=%dHz, %d samples/frame",	      clock_rate, samples_per_frame));    if (dir & PJMEDIA_DIR_PLAYBACK)	print_stream_data("Playback", &test_data, &test_data.playback_data, 			  verbose);    if (dir & PJMEDIA_DIR_CAPTURE)	print_stream_data("Capture", &test_data, &test_data.capture_data, 			   verbose);    /* Check drifting */    if (dir == PJMEDIA_DIR_CAPTURE_PLAYBACK) {	int end_diff, start_diff, drift;	end_diff = test_data.capture_data.last_timestamp -		   test_data.playback_data.last_timestamp;	start_diff = test_data.capture_data.first_timestamp-		      test_data.playback_data.first_timestamp;	drift = end_diff - start_diff;	PJ_LOG(3,(THIS_FILE, "  Checking for clock drifts:"));	/* Allow one frame tolerance for clock drift detection */	if (drift < (int)samples_per_frame) {	    PJ_LOG(3,(THIS_FILE, "   No clock drifts is detected"));	} else {	    const char *which = (drift<0 ? "slower" : "faster");	    unsigned msec_dur;	    if (drift < 0) drift = -drift;	    msec_dur = (test_data.capture_data.last_timestamp - 		       test_data.capture_data.first_timestamp) * 1000 /		       test_data.clock_rate;	    PJ_LOG(2,(THIS_FILE, 		      "   Sound capture is %d samples %s than playback "		      "at the end of the test (average is %d samples"		      " per second)",		      drift, which, 		      drift * 1000 / msec_dur));	}    }    if (test_data.has_error == 0) {	PJ_LOG(3,(THIS_FILE, " Test completed, sound device looks okay."));	return 0;    } else {	PJ_LOG(2,(THIS_FILE, " Test completed with some warnings"));	return 1;    }}int main(int argc, char *argv[]){    pj_caching_pool cp;    pjmedia_endpt *med_endpt;    int id = -1, verbose = 0;    int clock_rate = 8000;    int frame = -1;    int channel = 1;    struct pj_getopt_option long_options[] = {	{ "id",	     1, 0, 'i' },	{ "rate",    1, 0, 'r' },	{ "frame",   1, 0, 'f' },	{ "channel", 1, 0, 'n' },	{ "verbose", 0, 0, 'v' },	{ "help",    0, 0, 'h' },	{ NULL, 0, 0, 0 }    };    int c, option_index;        pj_status_t status;    /* Init pjlib */    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);    /* Print devices */    enum_devices();    /* Parse options */    pj_optind = 0;    while((c=pj_getopt_long(argc,argv, "i:r:f:n:vh", 			    long_options, &option_index))!=-1)     {	switch (c) {	case 'i':	    id = atoi(pj_optarg);	    break;	case 'r':	    clock_rate = atoi(pj_optarg);	    break;	case 'f':	    frame = atoi(pj_optarg);	    break;	case 'n':	    channel = atoi(pj_optarg);	    break;	case 'v':	    verbose = 1;	    break;	case 'h':	    puts(desc);	    return 0;	    break;	default:	    printf("Error: invalid options %s\n", argv[pj_optind-1]);	    puts(desc);	    return 1;	}    }    if (pj_optind != argc) {	printf("Error: invalid options\n");	puts(desc);	return 1;    }    if (!verbose)	pj_log_set_level(3);    if (frame == -1)	frame = 10 * clock_rate / 1000;    status = perform_test(id, PJMEDIA_DIR_CAPTURE_PLAYBACK, 			  clock_rate, frame, channel, verbose);    if (status != 0)	return 1;        return 0;}