示例#1
0
snd_pcm_t *open_pcm(char *pcm_name) {

    snd_pcm_t *playback_handle;
    snd_pcm_hw_params_t *hw_params;
    snd_pcm_sw_params_t *sw_params;
            
    if (snd_pcm_open (&playback_handle, pcm_name, SND_PCM_STREAM_PLAYBACK, 0) < 0) {
        fprintf (stderr, "cannot open audio device %s\n", pcm_name);
        exit (1);
    }
    snd_pcm_hw_params_alloca(&hw_params);
    snd_pcm_hw_params_any(playback_handle, hw_params);
    snd_pcm_hw_params_set_access(playback_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
    snd_pcm_hw_params_set_format(playback_handle, hw_params, SND_PCM_FORMAT_S16_LE);
    snd_pcm_hw_params_set_rate_near(playback_handle, hw_params, 44100, 0);
    snd_pcm_hw_params_set_channels(playback_handle, hw_params, 2);
    snd_pcm_hw_params_set_periods(playback_handle, hw_params, 2, 0);
    snd_pcm_hw_params_set_period_size(playback_handle, hw_params, BUFSIZE, 0);
    snd_pcm_hw_params(playback_handle, hw_params);
    snd_pcm_sw_params_alloca(&sw_params);
    snd_pcm_sw_params_current(playback_handle, sw_params);
    snd_pcm_sw_params_set_avail_min(playback_handle, sw_params, BUFSIZE);
    snd_pcm_sw_params(playback_handle, sw_params);
    return(playback_handle);
}
static int snd_pcm_ioctl_sw_params_compat(struct snd_pcm_substream *substream,
					  struct snd_pcm_sw_params32 __user *src)
{
	struct snd_pcm_sw_params params;
	snd_pcm_uframes_t boundary;
	int err;

	memset(&params, 0, sizeof(params));
	if (get_user(params.tstamp_mode, &src->tstamp_mode) ||
	    get_user(params.period_step, &src->period_step) ||
	    get_user(params.sleep_min, &src->sleep_min) ||
	    get_user(params.avail_min, &src->avail_min) ||
	    get_user(params.xfer_align, &src->xfer_align) ||
	    get_user(params.start_threshold, &src->start_threshold) ||
	    get_user(params.stop_threshold, &src->stop_threshold) ||
	    get_user(params.silence_threshold, &src->silence_threshold) ||
	    get_user(params.silence_size, &src->silence_size))
		return -EFAULT;
	/*
	 * Check silent_size parameter.  Since we have 64bit boundary,
	 * silence_size must be compared with the 32bit boundary.
	 */
	boundary = recalculate_boundary(substream->runtime);
	if (boundary && params.silence_size >= boundary)
		params.silence_size = substream->runtime->boundary;
	err = snd_pcm_sw_params(substream, &params);
	if (err < 0)
		return err;
	if (boundary && put_user(boundary, &src->boundary))
		return -EFAULT;
	return err;
}
// returns 1 if successful
int setSWParams(AlsaPcmInfo* info) {
    int ret;

    /* get the current swparams */
    ret = snd_pcm_sw_params_current(info->handle, info->swParams);
    if (ret < 0) {
        ERROR1("Unable to determine current swparams: %s\n", snd_strerror(ret));
        return FALSE;
    }
    /* never start the transfer automatically */
    if (!setStartThresholdNoCommit(info, FALSE /* don't use threshold */)) {
        return FALSE;
    }

    /* allow the transfer when at least period_size samples can be processed */
    ret = snd_pcm_sw_params_set_avail_min(info->handle, info->swParams, info->periodSize);
    if (ret < 0) {
        ERROR1("Unable to set avail min for playback: %s\n", snd_strerror(ret));
        return FALSE;
    }
    /* align all transfers to 1 sample */
    ret = snd_pcm_sw_params_set_xfer_align(info->handle, info->swParams, 1);
    if (ret < 0) {
        ERROR1("Unable to set transfer align: %s\n", snd_strerror(ret));
        return FALSE;
    }
    /* write the parameters to the playback device */
    ret = snd_pcm_sw_params(info->handle, info->swParams);
    if (ret < 0) {
        ERROR1("Unable to set sw params: %s\n", snd_strerror(ret));
        return FALSE;
    }
    return TRUE;
}
示例#4
0
文件: alsa.c 项目: ipoerner/transsip
static void alsa_set_sw_params(struct alsa_dev *dev, snd_pcm_t *handle,
			       int period, int thres)
{
	int ret;
	snd_pcm_sw_params_t *sw_params;

	ret = snd_pcm_sw_params_malloc(&sw_params);
	if (ret < 0)
		syslog_panic("Cannot allocate software parameters: %s\n",
			     snd_strerror(ret));
	ret = snd_pcm_sw_params_current(handle, sw_params);
	if (ret < 0)
		syslog_panic("Cannot initialize software parameters: %s\n",
			     snd_strerror(ret));
	ret = snd_pcm_sw_params_set_avail_min(handle, sw_params, period);
	if (ret < 0)
		syslog_panic("Cannot set minimum available count: %s\n",
			     snd_strerror(ret));
	if (thres) {
		ret = snd_pcm_sw_params_set_start_threshold(handle, sw_params,
							    period);
		if (ret < 0)
			syslog_panic("Cannot set start mode: %s\n",
				     snd_strerror(ret));
		
	}
	ret = snd_pcm_sw_params(handle, sw_params);
	if (ret < 0)
		syslog_panic("Cannot set software parameters: %s\n",
			     snd_strerror(ret));
	snd_pcm_sw_params_free(sw_params);
}
示例#5
0
static void audio_renderer_init() {
  int rc;
  decoder = opus_decoder_create(SAMPLE_RATE, CHANNEL_COUNT, &rc);

  snd_pcm_hw_params_t *hw_params;
  snd_pcm_sw_params_t *sw_params;
  snd_pcm_uframes_t period_size = FRAME_SIZE * CHANNEL_COUNT * 2;
  snd_pcm_uframes_t buffer_size = 12 * period_size;
  unsigned int sampleRate = SAMPLE_RATE;

  /* Open PCM device for playback. */
  CHECK_RETURN(snd_pcm_open(&handle, audio_device, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK))

  /* Set hardware parameters */
  CHECK_RETURN(snd_pcm_hw_params_malloc(&hw_params));
  CHECK_RETURN(snd_pcm_hw_params_any(handle, hw_params));
  CHECK_RETURN(snd_pcm_hw_params_set_access(handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED));
  CHECK_RETURN(snd_pcm_hw_params_set_format(handle, hw_params, SND_PCM_FORMAT_S16_LE));
  CHECK_RETURN(snd_pcm_hw_params_set_rate_near(handle, hw_params, &sampleRate, NULL));
  CHECK_RETURN(snd_pcm_hw_params_set_channels(handle, hw_params, CHANNEL_COUNT));
  CHECK_RETURN(snd_pcm_hw_params_set_buffer_size_near(handle, hw_params, &buffer_size));
  CHECK_RETURN(snd_pcm_hw_params_set_period_size_near(handle, hw_params, &period_size, NULL));
  CHECK_RETURN(snd_pcm_hw_params(handle, hw_params));
  snd_pcm_hw_params_free(hw_params);

  /* Set software parameters */
  CHECK_RETURN(snd_pcm_sw_params_malloc(&sw_params));
  CHECK_RETURN(snd_pcm_sw_params_current(handle, sw_params));
  CHECK_RETURN(snd_pcm_sw_params_set_start_threshold(handle, sw_params, buffer_size - period_size));
  CHECK_RETURN(snd_pcm_sw_params_set_avail_min(handle, sw_params, period_size));
  CHECK_RETURN(snd_pcm_sw_params(handle, sw_params));
  snd_pcm_sw_params_free(sw_params);

  CHECK_RETURN(snd_pcm_prepare(handle));
}
int set_swparams(snd_pcm_t *handle, snd_pcm_sw_params_t *swparams)
{
        int err;

        /* get the current swparams */
        err = snd_pcm_sw_params_current(handle, swparams);
        if (err < 0) {
                printf("Unable to determine current swparams for playback: %s\n", snd_strerror(err));
                return err;
        }
        /* start the transfer when the buffer is almost full: */
        /* (buffer_size / avail_min) * avail_min */
        //err = snd_pcm_sw_params_set_start_threshold(handle, swparams, (buffer_size / period_size) * period_size);
        err = snd_pcm_sw_params_set_start_threshold(handle, swparams, period_size * periods - arnold_frame_size);
        if (err < 0) {
                printf("Unable to set start threshold mode for playback: %s\n", snd_strerror(err));
                return err;
        }
        /* allow the transfer when at least period_size samples can be processed */
        err = snd_pcm_sw_params_set_avail_min(handle, swparams, arnold_frame_size);
        if (err < 0) {
                printf("Unable to set avail min for playback: %s\n", snd_strerror(err));
                return err;
        }
        /* write the parameters to the playback device */
        err = snd_pcm_sw_params(handle, swparams);
        if (err < 0) {
                printf("Unable to set sw params for playback: %s\n", snd_strerror(err));
                return err;
        }
        return 0;
}
示例#7
0
static int set_sw_params(snd_pcm_t *pcm,
                         snd_pcm_sw_params_t *sw_params,
                         snd_spcm_xrun_type_t xrun_type)
{
    int err;

    err = snd_pcm_sw_params_current(pcm, sw_params);
    if (err < 0)
        return err;
    err = snd_pcm_sw_params_set_start_threshold(pcm, sw_params, (pcm->buffer_size / pcm->period_size) * pcm->period_size);
    if (err < 0)
        return err;
    err = snd_pcm_sw_params_set_avail_min(pcm, sw_params, pcm->period_size);
    if (err < 0)
        return err;
    switch (xrun_type) {
    case SND_SPCM_XRUN_STOP:
        err = snd_pcm_sw_params_set_stop_threshold(pcm, sw_params, pcm->buffer_size);
        break;
    case SND_SPCM_XRUN_IGNORE:
        err = snd_pcm_sw_params_set_stop_threshold(pcm, sw_params, pcm->boundary);
        break;
    default:
        return -EINVAL;
    }
    if (err < 0)
        return err;
    err = snd_pcm_sw_params_set_xfer_align(pcm, sw_params, 1);
    if (err < 0)
        return err;
    err = snd_pcm_sw_params(pcm, sw_params);
    if (err < 0)
        return err;
    return 0;
}
示例#8
0
文件: tsmf_alsa.c 项目: BUGgs/FreeRDP
static BOOL tsmf_alsa_set_format(ITSMFAudioDevice *audio,
								 UINT32 sample_rate, UINT32 channels, UINT32 bits_per_sample)
{
	int error;
	snd_pcm_uframes_t frames;
	snd_pcm_hw_params_t *hw_params;
	snd_pcm_sw_params_t *sw_params;
	TSMFAlsaAudioDevice *alsa = (TSMFAlsaAudioDevice *) audio;
	if(!alsa->out_handle)
		return FALSE;
	snd_pcm_drop(alsa->out_handle);
	alsa->actual_rate = alsa->source_rate = sample_rate;
	alsa->actual_channels = alsa->source_channels = channels;
	alsa->bytes_per_sample = bits_per_sample / 8;
	error = snd_pcm_hw_params_malloc(&hw_params);
	if(error < 0)
	{
		WLog_ERR(TAG, "snd_pcm_hw_params_malloc failed");
		return FALSE;
	}
	snd_pcm_hw_params_any(alsa->out_handle, hw_params);
	snd_pcm_hw_params_set_access(alsa->out_handle, hw_params,
								 SND_PCM_ACCESS_RW_INTERLEAVED);
	snd_pcm_hw_params_set_format(alsa->out_handle, hw_params,
								 SND_PCM_FORMAT_S16_LE);
	snd_pcm_hw_params_set_rate_near(alsa->out_handle, hw_params,
									&alsa->actual_rate, NULL);
	snd_pcm_hw_params_set_channels_near(alsa->out_handle, hw_params,
										&alsa->actual_channels);
	frames = sample_rate;
	snd_pcm_hw_params_set_buffer_size_near(alsa->out_handle, hw_params,
										   &frames);
	snd_pcm_hw_params(alsa->out_handle, hw_params);
	snd_pcm_hw_params_free(hw_params);
	error = snd_pcm_sw_params_malloc(&sw_params);
	if(error < 0)
	{
		WLog_ERR(TAG, "snd_pcm_sw_params_malloc");
		return FALSE;
	}
	snd_pcm_sw_params_current(alsa->out_handle, sw_params);
	snd_pcm_sw_params_set_start_threshold(alsa->out_handle, sw_params,
										  frames / 2);
	snd_pcm_sw_params(alsa->out_handle, sw_params);
	snd_pcm_sw_params_free(sw_params);
	snd_pcm_prepare(alsa->out_handle);
	DEBUG_TSMF("sample_rate %d channels %d bits_per_sample %d",
			   sample_rate, channels, bits_per_sample);
	DEBUG_TSMF("hardware buffer %d frames", (int)frames);
	if((alsa->actual_rate != alsa->source_rate) ||
			(alsa->actual_channels != alsa->source_channels))
	{
		DEBUG_TSMF("actual rate %d / channel %d is different "
				   "from source rate %d / channel %d, resampling required.",
				   alsa->actual_rate, alsa->actual_channels,
				   alsa->source_rate, alsa->source_channels);
	}
	return TRUE;
}
示例#9
0
static av_cold int audio_read_header(AVFormatContext *s1,
                                     AVFormatParameters *ap)
{
    AlsaData *s = s1->priv_data;
    AVStream *st;
    int ret;
    enum CodecID codec_id;
    snd_pcm_sw_params_t *sw_params;

    st = av_new_stream(s1, 0);
    if (!st) {
        av_log(s1, AV_LOG_ERROR, "Cannot add stream\n");

        return AVERROR(ENOMEM);
    }
    codec_id    = s1->audio_codec_id;

    ret = ff_alsa_open(s1, SND_PCM_STREAM_CAPTURE, &s->sample_rate, s->channels,
        &codec_id);
    if (ret < 0) {
        return AVERROR(EIO);
    }

    if (snd_pcm_type(s->h) != SND_PCM_TYPE_HW)
        av_log(s1, AV_LOG_WARNING,
               "capture with some ALSA plugins, especially dsnoop, "
               "may hang.\n");

    ret = snd_pcm_sw_params_malloc(&sw_params);
    if (ret < 0) {
        av_log(s1, AV_LOG_ERROR, "cannot allocate software parameters structure (%s)\n",
               snd_strerror(ret));
        goto fail;
    }

    snd_pcm_sw_params_current(s->h, sw_params);
    snd_pcm_sw_params_set_tstamp_mode(s->h, sw_params, SND_PCM_TSTAMP_ENABLE);

    ret = snd_pcm_sw_params(s->h, sw_params);
    snd_pcm_sw_params_free(sw_params);
    if (ret < 0) {
        av_log(s1, AV_LOG_ERROR, "cannot install ALSA software parameters (%s)\n",
               snd_strerror(ret));
        goto fail;
    }

    /* take real parameters */
    st->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
    st->codec->codec_id    = codec_id;
    st->codec->sample_rate = s->sample_rate;
    st->codec->channels    = s->channels;
    av_set_pts_info(st, 64, 1, 1000000);  /* 64 bits pts in us */

    return 0;

fail:
    snd_pcm_close(s->h);
    return AVERROR(EIO);
}
示例#10
0
static int
set_params(struct alsa_device_data * alsa_data)
{
	snd_pcm_hw_params_t * hw_params;
	snd_pcm_sw_params_t * sw_params;
	int error;
	snd_pcm_uframes_t frames;

	snd_pcm_drop(alsa_data->out_handle);

	error = snd_pcm_hw_params_malloc(&hw_params);
	if (error < 0)
	{
		LLOGLN(0, ("set_params: snd_pcm_hw_params_malloc failed"));
		return 1;
	}
	snd_pcm_hw_params_any(alsa_data->out_handle, hw_params);
	snd_pcm_hw_params_set_access(alsa_data->out_handle, hw_params,
		SND_PCM_ACCESS_RW_INTERLEAVED);
	snd_pcm_hw_params_set_format(alsa_data->out_handle, hw_params,
		alsa_data->format);
	snd_pcm_hw_params_set_rate_near(alsa_data->out_handle, hw_params,
		&alsa_data->actual_rate, NULL);
	snd_pcm_hw_params_set_channels_near(alsa_data->out_handle, hw_params,
		&alsa_data->actual_channels);
	frames = alsa_data->actual_rate * 4;
	snd_pcm_hw_params_set_buffer_size_near(alsa_data->out_handle, hw_params,
		&frames);
	snd_pcm_hw_params(alsa_data->out_handle, hw_params);
	snd_pcm_hw_params_free(hw_params);

	error = snd_pcm_sw_params_malloc(&sw_params);
	if (error < 0)
	{
		LLOGLN(0, ("set_params: snd_pcm_sw_params_malloc"));
		return 1;
	}
	snd_pcm_sw_params_current(alsa_data->out_handle, sw_params);
	snd_pcm_sw_params_set_start_threshold(alsa_data->out_handle, sw_params,
		frames / 2);
	snd_pcm_sw_params(alsa_data->out_handle, sw_params);
	snd_pcm_sw_params_free(sw_params);

	snd_pcm_prepare(alsa_data->out_handle);

	LLOGLN(10, ("set_params: hardware buffer %d frames, playback buffer %.2g seconds",
		(int)frames, (double)frames / 2.0 / (double)alsa_data->actual_rate));
	if ((alsa_data->actual_rate != alsa_data->source_rate) ||
		(alsa_data->actual_channels != alsa_data->source_channels))
	{
		LLOGLN(0, ("set_params: actual rate %d / channel %d is different from source rate %d / channel %d, resampling required.",
			alsa_data->actual_rate, alsa_data->actual_channels, alsa_data->source_rate, alsa_data->source_channels));
	}
	return 0;
}
示例#11
0
文件: AudioAlsa.cpp 项目: uro5h/lmms
int AudioAlsa::setSWParams()
{
	int err;

	// get the current swparams
	if( ( err = snd_pcm_sw_params_current( m_handle, m_swParams ) ) < 0 )
	{
		printf( "Unable to determine current swparams for playback: %s"
						"\n", snd_strerror( err ) );
		return err;
	}

	// start the transfer when a period is full
	if( ( err = snd_pcm_sw_params_set_start_threshold( m_handle,
					m_swParams, m_periodSize ) ) < 0 )
	{
		printf( "Unable to set start threshold mode for playback: %s\n",
							snd_strerror( err ) );
		return err;
	}

	// allow the transfer when at least m_periodSize samples can be
	// processed
	if( ( err = snd_pcm_sw_params_set_avail_min( m_handle, m_swParams,
							m_periodSize ) ) < 0 )
	{
		printf( "Unable to set avail min for playback: %s\n",
							snd_strerror( err ) );
		return err;
	}

	// align all transfers to 1 sample
	
#if SND_LIB_VERSION < ((1<<16)|(0)|16)
	if( ( err = snd_pcm_sw_params_set_xfer_align( m_handle,
							m_swParams, 1 ) ) < 0 )
	{
		printf( "Unable to set transfer align for playback: %s\n",
							snd_strerror( err ) );
		return err;
	}
#endif

	// write the parameters to the playback device
	if( ( err = snd_pcm_sw_params( m_handle, m_swParams ) ) < 0 )
	{
		printf( "Unable to set sw params for playback: %s\n",
							snd_strerror( err ) );
		return err;
	}

	return 0;	// all ok
}
示例#12
0
文件: mixer.c 项目: wsmind/funpad
void mixer_open()
{
	memset(&channels, 0, sizeof(channels));
	int err = snd_pcm_open(&pcm, "default", SND_PCM_STREAM_PLAYBACK, 0);
	if (err < 0)
	{
		printf("Failed to open pcm device: %s\n", snd_strerror(err));
		exit(1);
	}
	
	unsigned int rate = 44100;
	snd_pcm_hw_params_t *hw_params = 0;
	snd_pcm_hw_params_alloca(&hw_params);
	snd_pcm_hw_params_any(pcm, hw_params);
	snd_pcm_hw_params_set_rate_resample(pcm, hw_params, 0);
	snd_pcm_hw_params_set_access(pcm, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
	snd_pcm_hw_params_set_format(pcm, hw_params, SND_PCM_FORMAT_S16_LE);
	snd_pcm_hw_params_set_rate_near(pcm, hw_params, &rate, 0);
	snd_pcm_hw_params_set_channels(pcm, hw_params, 2);
	snd_pcm_hw_params_set_period_size(pcm, hw_params, BUFFER_SIZE, 0);
	snd_pcm_hw_params_set_buffer_size(pcm, hw_params, BUFFER_SIZE * 4);
	
	err = snd_pcm_hw_params(pcm, hw_params);
	if (err < 0)
	{
		printf("Failed to apply pcm hardware settings: %s\n", snd_strerror(err));
		exit(1);
	}
	
	snd_pcm_sw_params_t *sw_params = 0;
	snd_pcm_sw_params_alloca(&sw_params);
	snd_pcm_sw_params_current(pcm, sw_params);
	snd_pcm_sw_params_set_avail_min(pcm, sw_params, BUFFER_SIZE * 4);
	err = snd_pcm_sw_params(pcm, sw_params);
	if (err < 0)
	{
		printf("Failed to apply pcm software settings: %s\n", snd_strerror(err));
		exit(1);
	}
	
	err = snd_pcm_prepare(pcm);
	if (err < 0)
	{
		printf("Failed to prepare pcm interface: %s\n", snd_strerror(err));
		exit(1);
	}
	
	memset(delay_left, 0, sizeof(delay_left));
	memset(delay_right, 0, sizeof(delay_right));
}
示例#13
0
static int setparams_set(snd_pcm_t *handle,
                         snd_pcm_hw_params_t *params,
                         snd_pcm_sw_params_t *swparams,
                         snd_pcm_uframes_t start_treshold,
                         const char *id)
{
    int err;

    err = snd_pcm_hw_params(handle, params);
    if (err < 0) {
        fprintf(error_fp, "alsa: Unable to set hw params for %s: %s\n",
                id, snd_strerror(err));
        return err;
    }
    err = snd_pcm_sw_params_current(handle, swparams);
    if (err < 0) {
        fprintf(error_fp, "alsa: Unable to determine current swparams for %s: %s\n",
                id, snd_strerror(err));
        return err;
    }
    err = snd_pcm_sw_params_set_start_threshold(handle, swparams,
            start_treshold);
    if (err < 0) {
        fprintf(error_fp, "alsa: Unable to set start threshold mode for %s: %s\n",
                id, snd_strerror(err));
        return err;
    }

    err = snd_pcm_sw_params_set_avail_min(handle, swparams, 4);
    if (err < 0) {
        fprintf(error_fp, "alsa: Unable to set avail min for %s: %s\n",
                id, snd_strerror(err));
        return err;
    }

    err = snd_pcm_sw_params_set_tstamp_mode(handle, swparams, SND_PCM_TSTAMP_ENABLE);
    if (err < 0) {
        fprintf(error_fp, "alsa: Unable to enable timestamps for %s: %s\n",
                id, snd_strerror(err));
    }

    err = snd_pcm_sw_params(handle, swparams);
    if (err < 0) {
        fprintf(error_fp, "alsa: Unable to set sw params for %s: %s\n",
                id, snd_strerror(err));
        return err;
    }
    return 0;
}
int setStartThreshold(AlsaPcmInfo* info, int useThreshold) {
    int ret = 0;

    if (!setStartThresholdNoCommit(info, useThreshold)) {
        ret = -1;
    }
    if (ret == 0) {
        // commit it
        ret = snd_pcm_sw_params(info->handle, info->swParams);
        if (ret < 0) {
            ERROR1("Unable to set sw params: %s\n", snd_strerror(ret));
        }
    }
    return (ret == 0)?TRUE:FALSE;
}
示例#15
0
/**************************************************************************************
 * set_swparams
 * history: (1) 2014 03 30 mhb
 *
 **************************************************************************************/
static int set_swparams(snd_pcm_t *handle, 
                        snd_pcm_sw_params_t *swparams)
{
    int err;
    /* get the current swparams */
    err = snd_pcm_sw_params_current(handle, swparams);
    if (err < 0) 
    {
        printf("Unable to determine current swparams : %s\n", snd_strerror(err));
        return err;
    }
    /* start the transfer when the buffer is almost full: */
    /* (buffer_size / avail_min) * avail_min */
    err = snd_pcm_sw_params_set_start_threshold(handle, swparams, (buffer_size / period_size) * period_size);
    //err = snd_pcm_sw_params_set_start_threshold(handle, swparams, 3*period_size);// mhb|  修改此值,太小程序会卡死
    if (err < 0) 
    {
        printf("Unable to set start threshold mode : %s\n", snd_strerror(err));
        return err;
    }
    /* allow the transfer when at least period_size samples can be processed */
    /* or disable this mechanism when period event is enabled (aka interrupt like style processing) */
    err = snd_pcm_sw_params_set_avail_min(handle, swparams, period_event ? buffer_size : period_size);
    //err = snd_pcm_sw_params_set_avail_min(handle, swparams, 0);//mhb
    if (err < 0) 
    {
        printf("Unable to set avail min : %s\n", snd_strerror(err));
        return err;
    }
    /* enable period events when requested */
    if (period_event) 
    {
        err = snd_pcm_sw_params_set_period_event(handle, swparams, 1);
        if (err < 0) 
        {
            printf("Unable to set period event: %s\n", snd_strerror(err));
            return err;
        }
    }
    /* write the parameters to the playback device */
    err = snd_pcm_sw_params(handle, swparams);
    if (err < 0) 
    {
        printf("Unable to set sw params : %s\n", snd_strerror(err));
        return err;
    }
    return 0;
}
int
set_mic_swparams(snd_pcm_t *handle) 
{
    // set software params

    snd_pcm_sw_params_t *swparams;
    snd_pcm_sw_params_alloca(&swparams);

    /* get the current swparams */
    int ret = snd_pcm_sw_params_current(handle, swparams);
    if (ret < 0) {
        fprintf(stderr, 
	    "Unable to determine current swparams for mic: %s\n", 
	    snd_strerror(ret));
        return ret;
    }

    /* allow transfer when at least period_frames can be processed */

    ret = snd_pcm_sw_params_set_avail_min(handle, swparams, 
	get_period_frames(handle));

    if (ret < 0) {
        fprintf(stderr, "Unable to set avail min for mic: %s\n", 
	    snd_strerror(ret));
        return ret;
    }

    /* align all transfers to 1 sample */
    ret = snd_pcm_sw_params_set_xfer_align(handle, swparams, 1);
    if (ret < 0) {
        fprintf(stderr, "Unable to set transfer align for mic: %s\n", 
	    snd_strerror(ret));
        return ret;
    }

    /* write the parameters to the microphone device */
    ret = snd_pcm_sw_params(handle, swparams);
    if (ret < 0) {
        fprintf(stderr, "Unable to set sw params for mic: %s\n", 
	    snd_strerror(ret));
        return ret;
    }
	
    dump_swparams(handle);
    return 0;
}
示例#17
0
static int alsa_set_hwparams()
{
	snd_pcm_hw_params_t *hwp;
	snd_pcm_sw_params_t *swp;
	int dir = 1;
	unsigned period_time;
	snd_pcm_uframes_t buffer_size, period_size;

	snd_pcm_hw_params_alloca(&hwp);
	snd_pcm_sw_params_alloca(&swp);

	// ALSA bug? If we request 44100 Hz, it rounds the value up to 48000...
	alsa_hw.rate--;

	if (alsa_error("hw_params_any", snd_pcm_hw_params_any(alsa_hw.handle, hwp))
	    || alsa_error("hw_params_set_format", snd_pcm_hw_params_set_format(alsa_hw.handle, hwp, alsa_hw.format))
	    || alsa_error("hw_params_set_channels",
			  snd_pcm_hw_params_set_channels(alsa_hw.handle, hwp, alsa_hw.num_channels))
	    || alsa_error("hw_params_set_rate_near",
			  snd_pcm_hw_params_set_rate_near(alsa_hw.handle, hwp, &alsa_hw.rate, &dir))
	    || alsa_error("hw_params_set_access",
			  snd_pcm_hw_params_set_access(alsa_hw.handle, hwp, SND_PCM_ACCESS_RW_INTERLEAVED))
	    || alsa_error("hw_params_set_buffer_time_near",
			  snd_pcm_hw_params_set_buffer_time_near(alsa_hw.handle, hwp, &alsa_hw.buffer_time, 0)))
		return -1;

	/* How often to call our SIGIO handler (~40Hz) */
	period_time = alsa_hw.buffer_time / 4;
	if (alsa_error
	    ("hw_params_set_period_time_near",
	     snd_pcm_hw_params_set_period_time_near(alsa_hw.handle, hwp, &period_time, &dir))
	    || alsa_error("hw_params_get_buffer_size", snd_pcm_hw_params_get_buffer_size(hwp, &buffer_size))
	    || alsa_error("hw_params_get_period_size", snd_pcm_hw_params_get_period_size(hwp, &period_size, 0))
	    || alsa_error("hw_params", snd_pcm_hw_params(alsa_hw.handle, hwp)))
		return -1;

	snd_pcm_sw_params_current(alsa_hw.handle, swp);
	if (alsa_error
	    ("sw_params_set_start_threshold", snd_pcm_sw_params_set_start_threshold(alsa_hw.handle, swp, period_size))
	    || alsa_error("sw_params_set_avail_min", snd_pcm_sw_params_set_avail_min(alsa_hw.handle, swp, period_size))
	    || alsa_error("sw_params", snd_pcm_sw_params(alsa_hw.handle, swp)))
		return -1;

	return 0;
}
示例#18
0
static int
laudio_alsa_set_start_threshold(snd_pcm_uframes_t threshold)
{
  snd_pcm_sw_params_t *sw_params;
  int ret;

  ret = snd_pcm_sw_params_malloc(&sw_params);
  if (ret < 0)
    {
      DPRINTF(E_LOG, L_LAUDIO, "Could not allocate sw params: %s\n", snd_strerror(ret));

      goto out_fail;
    }

  ret = snd_pcm_sw_params_current(hdl, sw_params);
  if (ret < 0)
    {
      DPRINTF(E_LOG, L_LAUDIO, "Could not retrieve current sw params: %s\n", snd_strerror(ret));

      goto out_fail;
    }

  ret = snd_pcm_sw_params_set_start_threshold(hdl, sw_params, threshold);
  if (ret < 0)
    {
      DPRINTF(E_LOG, L_LAUDIO, "Could not set start threshold: %s\n", snd_strerror(ret));

      goto out_fail;
    }

  ret = snd_pcm_sw_params(hdl, sw_params);
  if (ret < 0)
    {
      DPRINTF(E_LOG, L_LAUDIO, "Could not set sw params: %s\n", snd_strerror(ret));

      goto out_fail;
    }

  return 0;

 out_fail:
  snd_pcm_sw_params_free(sw_params);

  return -1;
}
static int drvHostALSAAudioSetThreshold(snd_pcm_t *phPCM,
                                        snd_pcm_uframes_t threshold)
{
    snd_pcm_sw_params_t *pSWParms = NULL;
    snd_pcm_sw_params_alloca(&pSWParms);
    if (!pSWParms)
        return VERR_NO_MEMORY;

    int rc;
    do
    {
        int err = snd_pcm_sw_params_current(phPCM, pSWParms);
        if (err < 0)
        {
            LogRel(("ALSA: Failed to get current software parameters for threshold: %s\n",
                    snd_strerror(err)));
            rc = VERR_ACCESS_DENIED;
            break;
        }

        err = snd_pcm_sw_params_set_start_threshold(phPCM, pSWParms, threshold);
        if (err < 0)
        {
            LogRel(("ALSA: Failed to set software threshold to %ld: %s\n",
                    threshold, snd_strerror(err)));
            rc = VERR_ACCESS_DENIED;
            break;
        }

        err = snd_pcm_sw_params(phPCM, pSWParms);
        if (err < 0)
        {
            LogRel(("ALSA: Failed to set new software parameters for threshold: %s\n",
                    snd_strerror(err)));
            rc = VERR_ACCESS_DENIED;
            break;
        }

        LogFlowFunc(("Setting threshold to %RU32\n", threshold));
        rc = VINF_SUCCESS;
    }
    while (0);

    return rc;
}
/* setup alsa data transfer behavior */
static inline int alsa_set_swparams(ao_alsa_internal *internal)
{
	snd_pcm_sw_params_t   *params;
	int err;

	/* allocate the software parameter structure */
	snd_pcm_sw_params_alloca(&params);

	/* fetch the current software parameters */
	internal->cmd = "snd_pcm_sw_params_current";
	err = snd_pcm_sw_params_current(internal->pcm_handle, params);
	if (err < 0)
		return err;

	/* allow transfers to start when there is one period */
	internal->cmd = "snd_pcm_sw_params_set_start_threshold";
	err = snd_pcm_sw_params_set_start_threshold(internal->pcm_handle,
			params, internal->period_size);
	if (err < 0)
		return err;

	/* require a minimum of one full transfer in the buffer */
	internal->cmd = "snd_pcm_sw_params_set_avail_min";
	err = snd_pcm_sw_params_set_avail_min(internal->pcm_handle, params,
			internal->period_size);
	if (err < 0)
		return err;

	/* do not align transfers */
	internal->cmd = "snd_pcm_sw_params_set_xfer_align";
	err = snd_pcm_sw_params_set_xfer_align(internal->pcm_handle, params, 1);
	if (err < 0)
		return err;

	/* commit the params structure to ALSA */
	internal->cmd = "snd_pcm_sw_params";
	err = snd_pcm_sw_params(internal->pcm_handle, params);
	if (err < 0)
		return err;

	return 1;
}
示例#21
0
void AlsaRenderer::SetupSwParams()
{
    snd_pcm_sw_params_t* params;

    /* allocate a software parameters object */
    snd_pcm_sw_params_malloc(&params);

    /* get the current swparams */
    snd_pcm_sw_params_current(m_PcmHandle, params);

    /* round up to closest transfer boundary */
    snd_pcm_sw_params_set_start_threshold(m_PcmHandle, params, 1);

    /* require a minimum of one full transfer in the buffer */
    snd_pcm_sw_params_set_avail_min(m_PcmHandle, params, 1);

    snd_pcm_sw_params(m_PcmHandle, params);

    /* free */
    snd_pcm_sw_params_free(params);
}
示例#22
0
文件: alsa_out.c 项目: recri/keyer
static int set_swparams(snd_pcm_t *handle, snd_pcm_sw_params_t *swparams, int period, int nperiods) {
	int err;

	/* get the current swparams */
	err = snd_pcm_sw_params_current(handle, swparams);
	if (err < 0) {
		printf("Unable to determine current swparams for capture: %s\n", snd_strerror(err));
		return err;
	}
	/* start the transfer when the buffer is full */
	err = snd_pcm_sw_params_set_start_threshold(handle, swparams, period );
	if (err < 0) {
		printf("Unable to set start threshold mode for capture: %s\n", snd_strerror(err));
		return err;
	}
	err = snd_pcm_sw_params_set_stop_threshold(handle, swparams, -1 );
	if (err < 0) {
		printf("Unable to set start threshold mode for capture: %s\n", snd_strerror(err));
		return err;
	}
	/* allow the transfer when at least period_size samples can be processed */
	err = snd_pcm_sw_params_set_avail_min(handle, swparams, 1 );
	if (err < 0) {
		printf("Unable to set avail min for capture: %s\n", snd_strerror(err));
		return err;
	}
	/* align all transfers to 1 sample */
	err = snd_pcm_sw_params_set_xfer_align(handle, swparams, 1);
	if (err < 0) {
		printf("Unable to set transfer align for capture: %s\n", snd_strerror(err));
		return err;
	}
	/* write the parameters to the playback device */
	err = snd_pcm_sw_params(handle, swparams);
	if (err < 0) {
		printf("Unable to set sw params for capture: %s\n", snd_strerror(err));
		return err;
	}
	return 0;
}
int setparams_set(snd_pcm_t *handle,
		  snd_pcm_hw_params_t *params,
		  snd_pcm_sw_params_t *swparams,
		  const char *id)
{
	int err;
	snd_pcm_uframes_t val;

	err = snd_pcm_hw_params(handle, params);
	if (err < 0) {
		printf("Unable to set hw params for %s: %s\n", id, snd_strerror(err));
		return err;
	}
	err = snd_pcm_sw_params_current(handle, swparams);
	if (err < 0) {
		printf("Unable to determine current swparams for %s: %s\n", id, snd_strerror(err));
		return err;
	}
	err = snd_pcm_sw_params_set_start_threshold(handle, swparams, 0x7fffffff);
	if (err < 0) {
		printf("Unable to set start threshold mode for %s: %s\n", id, snd_strerror(err));
		return err;
	}
	if (!block)
		val = 4;
	else
		snd_pcm_hw_params_get_period_size(params, &val, NULL);
	err = snd_pcm_sw_params_set_avail_min(handle, swparams, val);
	if (err < 0) {
		printf("Unable to set avail min for %s: %s\n", id, snd_strerror(err));
		return err;
	}
	err = snd_pcm_sw_params(handle, swparams);
	if (err < 0) {
		printf("Unable to set sw params for %s: %s\n", id, snd_strerror(err));
		return err;
	}
	return 0;
}
示例#24
0
snd_pcm_t *open_pcm(char *pcm_name) {
    snd_pcm_t *playback_handle;
    snd_pcm_hw_params_t *hw_params;
    snd_pcm_sw_params_t *sw_params;
    if (snd_pcm_open (&playback_handle, pcm_name, SND_PCM_STREAM_PLAYBACK, 0) < 0) {
        fprintf (stderr, "cannot open audio device %s\n", pcm_name);
      return NULL;//it seems greedy and wants exclusive control?!
    }
    snd_pcm_hw_params_alloca(&hw_params);
    snd_pcm_hw_params_any(playback_handle, hw_params);
    snd_pcm_hw_params_set_access(playback_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
    snd_pcm_hw_params_set_format(playback_handle, hw_params, SND_PCM_FORMAT_S16_LE);
    snd_pcm_hw_params_set_rate_near(playback_handle, hw_params, &rate, 0);
    snd_pcm_hw_params_set_channels(playback_handle, hw_params, 2);
    snd_pcm_hw_params_set_periods(playback_handle, hw_params, 2, 0);
    snd_pcm_hw_params_set_period_size(playback_handle, hw_params, BUFSAMPS, 0);
    snd_pcm_hw_params(playback_handle, hw_params);
    snd_pcm_sw_params_alloca(&sw_params);
    snd_pcm_sw_params_current(playback_handle, sw_params);
    snd_pcm_sw_params_set_avail_min(playback_handle, sw_params, BUFSAMPS);
    snd_pcm_sw_params(playback_handle, sw_params);
    return(playback_handle);
}
示例#25
0
bool CAESinkALSA::InitializeSW(AEAudioFormat &format)
{
  snd_pcm_sw_params_t *sw_params;
  snd_pcm_uframes_t boundary;

  snd_pcm_sw_params_alloca(&sw_params);
  memset(sw_params, 0, snd_pcm_sw_params_sizeof());

  snd_pcm_sw_params_current              (m_pcm, sw_params);
  snd_pcm_sw_params_set_start_threshold  (m_pcm, sw_params, INT_MAX);
  snd_pcm_sw_params_set_silence_threshold(m_pcm, sw_params, 0);
  snd_pcm_sw_params_get_boundary         (sw_params, &boundary);
  snd_pcm_sw_params_set_silence_size     (m_pcm, sw_params, boundary);
  snd_pcm_sw_params_set_avail_min        (m_pcm, sw_params, format.m_frames);

  if (snd_pcm_sw_params(m_pcm, sw_params) < 0)
  {
    CLog::Log(LOGERROR, "CAESinkALSA::InitializeSW - Failed to set the parameters");
    return false;
  }

  return true;
}
示例#26
0
bool AudioInputALSA::PrepSwParams(void)
{
    snd_pcm_sw_params_t* swparams;
    snd_pcm_sw_params_alloca(&swparams);
    snd_pcm_uframes_t boundary;
    if (AlsaBad(snd_pcm_sw_params_current(pcm_handle, swparams),
                "failed to get swparams"))
        return false;
    if (AlsaBad(snd_pcm_sw_params_get_boundary(swparams, &boundary),
                "failed to get boundary"))
        return false;
    // explicit start, not auto start
    if (AlsaBad(snd_pcm_sw_params_set_start_threshold(pcm_handle, swparams,
                boundary), "failed to set start threshold"))
        return false;
    if (AlsaBad(snd_pcm_sw_params_set_stop_threshold(pcm_handle, swparams,
                boundary), "failed to set stop threshold"))
        return false;
    if (AlsaBad(snd_pcm_sw_params(pcm_handle, swparams),
                "failed to set software parameters"))
        return false;

    return true;
}
示例#27
0
int ai_alsa_setup(audio_in_t *ai)
{
    snd_pcm_hw_params_t *params;
    snd_pcm_sw_params_t *swparams;
    snd_pcm_uframes_t buffer_size, period_size;
    int err;
    int dir;
    unsigned int rate;

    snd_pcm_hw_params_alloca(&params);
    snd_pcm_sw_params_alloca(&swparams);

    err = snd_pcm_hw_params_any(ai->alsa.handle, params);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Broken configuration for this PCM: no configurations available.\n");
	return -1;
    }

    err = snd_pcm_hw_params_set_access(ai->alsa.handle, params,
				       SND_PCM_ACCESS_RW_INTERLEAVED);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Access type not available.\n");
	return -1;
    }

    err = snd_pcm_hw_params_set_format(ai->alsa.handle, params, SND_PCM_FORMAT_S16_LE);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Sample format not available.\n");
	return -1;
    }

    err = snd_pcm_hw_params_set_channels(ai->alsa.handle, params, ai->req_channels);
    if (err < 0) {
	snd_pcm_hw_params_get_channels(params, &ai->channels);
	mp_tmsg(MSGT_TV, MSGL_ERR, "Channel count not available - reverting to default: %d\n",
	       ai->channels);
    } else {
	ai->channels = ai->req_channels;
    }

    dir = 0;
    rate = ai->req_samplerate;
    err = snd_pcm_hw_params_set_rate_near(ai->alsa.handle, params, &rate, &dir);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Cannot set samplerate.\n");
    }
    ai->samplerate = rate;

    dir = 0;
    ai->alsa.buffer_time = 1000000;
    err = snd_pcm_hw_params_set_buffer_time_near(ai->alsa.handle, params,
						 &ai->alsa.buffer_time, &dir);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Cannot set buffer time.\n");
    }

    dir = 0;
    ai->alsa.period_time = ai->alsa.buffer_time / 4;
    err = snd_pcm_hw_params_set_period_time_near(ai->alsa.handle, params,
						 &ai->alsa.period_time, &dir);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Cannot set period time.\n");
    }

    err = snd_pcm_hw_params(ai->alsa.handle, params);
    if (err < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Unable to install hardware parameters: %s", snd_strerror(err));
	snd_pcm_hw_params_dump(params, ai->alsa.log);
	return -1;
    }

    dir = -1;
    snd_pcm_hw_params_get_period_size(params, &period_size, &dir);
    snd_pcm_hw_params_get_buffer_size(params, &buffer_size);
    ai->alsa.chunk_size = period_size;
    if (period_size == buffer_size) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Can't use period equal to buffer size (%u == %lu)\n", ai->alsa.chunk_size, (long)buffer_size);
	return -1;
    }

    snd_pcm_sw_params_current(ai->alsa.handle, swparams);
    err = snd_pcm_sw_params_set_avail_min(ai->alsa.handle, swparams, ai->alsa.chunk_size);

    err = snd_pcm_sw_params_set_start_threshold(ai->alsa.handle, swparams, 0);
    err = snd_pcm_sw_params_set_stop_threshold(ai->alsa.handle, swparams, buffer_size);

    if (snd_pcm_sw_params(ai->alsa.handle, swparams) < 0) {
	mp_tmsg(MSGT_TV, MSGL_ERR, "Unable to install software parameters:\n");
	snd_pcm_sw_params_dump(swparams, ai->alsa.log);
	return -1;
    }

    if (mp_msg_test(MSGT_TV, MSGL_V)) {
	snd_pcm_dump(ai->alsa.handle, ai->alsa.log);
    }

    ai->alsa.bits_per_sample = snd_pcm_format_physical_width(SND_PCM_FORMAT_S16_LE);
    ai->alsa.bits_per_frame = ai->alsa.bits_per_sample * ai->channels;
    ai->blocksize = ai->alsa.chunk_size * ai->alsa.bits_per_frame / 8;
    ai->samplesize = ai->alsa.bits_per_sample;
    ai->bytes_per_sample = ai->alsa.bits_per_sample/8;

    return 0;
}
示例#28
0
文件: alsa.c 项目: pmyadlowsky/mash
static int capture(lua_State *lstate) {
	char *card;
	snd_pcm_sw_params_t *sparams;
	int ret, dir, i;
	snd_pcm_format_t f, format;
	unsigned int rate, buffer_time;
	if (rbuf == NULL) {
		rbuf = new_ringbuf(jack_sr, CHANNELS, BUFSECS,
					0.333, 0.667);
		}
	getstring(lstate, "card", &card);
	lua_pop(lstate, 1);
	for (i = 0; i < 20; i++) {
		ret = snd_pcm_open(&handle, card, SND_PCM_STREAM_CAPTURE, 0);
		if (ret < 0) {
			logmsg("can't open %s (%s)\n", card, snd_strerror(ret));
			}
		else {
			break;
			}
		}
	free(card);
	if (ret < 0) return 0;
	if (hparams != NULL) snd_pcm_hw_params_free(hparams);
	snd_pcm_hw_params_malloc(&hparams);
	snd_pcm_hw_params_any(handle, hparams);
	for (f = format = 0; f < SND_PCM_FORMAT_LAST; f++) {
		ret = snd_pcm_hw_params_test_format(handle, hparams, f);
		if (ret == 0) {
			logmsg("- %s\n", snd_pcm_format_name(f));
			format = f;
			}
		}
	ret = snd_pcm_hw_params_set_access(handle, hparams,
				SND_PCM_ACCESS_RW_INTERLEAVED);
	if (ret < 0) {
		logmsg("access %s\n", snd_strerror(ret));
		}
	ret = snd_pcm_hw_params_set_format(handle, hparams, format);
	logmsg("format: %s\n", snd_pcm_format_description(format));
	if (ret < 0) {
		logmsg("format error %s\n", snd_strerror(ret));
		}
	snd_pcm_hw_params_get_buffer_time_max(hparams, &buffer_time, 0);
	rate = jack_sr;
	ret = snd_pcm_hw_params_set_rate(handle, hparams, rate, 0);
logmsg("rate %d\n", rate);
	if (ret < 0) logmsg("rate error %s\n", snd_strerror(ret));
	snd_pcm_hw_params_set_channels(handle, hparams, CHANNELS);
	blocksize = BLOCKSIZE;
	snd_pcm_hw_params_set_period_size(handle, hparams, blocksize, 0);
logmsg("period %ld\n", blocksize);
	snd_pcm_hw_params_set_buffer_time_near(handle, hparams, &buffer_time, &dir);
logmsg("buffer time %u\n", buffer_time);
	if ((ret = snd_pcm_hw_params(handle, hparams)) < 0) {
		logmsg("can't set hardware: %s\n",
			snd_strerror(ret));
		return 0;
		}
	else logmsg("hardware configd\n");
	snd_pcm_sw_params_malloc(&sparams);
	snd_pcm_sw_params_current(handle, sparams);
	snd_pcm_sw_params_set_avail_min(handle, sparams, blocksize);
	snd_pcm_sw_params_set_start_threshold(handle, sparams, 0U);
	if ((ret = snd_pcm_sw_params(handle, sparams)) < 0) {
		logmsg("can't set software: %s\n",
			snd_strerror(ret));
		}
	else logmsg("software configd\n");
	snd_pcm_sw_params_free(sparams);
	pthread_create(&thread_id, NULL, dev_thread, NULL);
	return 0;
	}
bool QAudioOutputPrivate::open()
{
    if(opened)
        return true;

#ifdef DEBUG_AUDIO
    QTime now(QTime::currentTime());
    qDebug()<<now.second()<<"s "<<now.msec()<<"ms :open()";
#endif
    timeStamp.restart();
    elapsedTimeOffset = 0;

    int dir;
    int err=-1;
    int count=0;
    unsigned int freakuency=settings.frequency();

    QString dev = QLatin1String(m_device.constData());
    QList<QByteArray> devices = QAudioDeviceInfoInternal::availableDevices(QAudio::AudioOutput);
    if(dev.compare(QLatin1String("default")) == 0) {
#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14)
        dev = QLatin1String(devices.first().constData());
#else
        dev = QLatin1String("hw:0,0");
#endif
    } else {
#if(SND_LIB_MAJOR == 1 && SND_LIB_MINOR == 0 && SND_LIB_SUBMINOR >= 14)
        dev = QLatin1String(m_device);
#else
        int idx = 0;
        char *name;

        QString shortName = QLatin1String(m_device.mid(m_device.indexOf('=',0)+1).constData());

	while(snd_card_get_name(idx,&name) == 0) {
            if(qstrncmp(shortName.toLocal8Bit().constData(),name,shortName.length()) == 0)
                break;
            idx++;
	}
        dev = QString(QLatin1String("hw:%1,0")).arg(idx);
#endif
    }

    // Step 1: try and open the device
    while((count < 5) && (err < 0)) {
        err=snd_pcm_open(&handle,dev.toLocal8Bit().constData(),SND_PCM_STREAM_PLAYBACK,0);
        if(err < 0)
            count++;
    }
    if (( err < 0)||(handle == 0)) {
        errorState = QAudio::OpenError;
        deviceState = QAudio::StoppedState;
        return false;
    }
    snd_pcm_nonblock( handle, 0 );

    // Step 2: Set the desired HW parameters.
    snd_pcm_hw_params_alloca( &hwparams );

    bool fatal = false;
    QString errMessage;
    unsigned int chunks = 8;

    err = snd_pcm_hw_params_any( handle, hwparams );
    if ( err < 0 ) {
        fatal = true;
        errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_any: err = %1").arg(err);
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_rate_resample( handle, hwparams, 1 );
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_rate_resample: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_access( handle, hwparams, access );
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_access: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = setFormat();
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_format: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_channels( handle, hwparams, (unsigned int)settings.channels() );
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_channels: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_rate_near( handle, hwparams, &freakuency, 0 );
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_rate_near: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_buffer_time_near(handle, hwparams, &buffer_time, &dir);
        if ( err < 0 ) {
            fatal = true;
                errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_buffer_time_near: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_period_time_near(handle, hwparams, &period_time, &dir);
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_period_time_near: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params_set_periods_near(handle, hwparams, &chunks, &dir);
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params_set_periods_near: err = %1").arg(err);
        }
    }
    if ( !fatal ) {
        err = snd_pcm_hw_params(handle, hwparams);
        if ( err < 0 ) {
            fatal = true;
            errMessage = QString::fromLatin1("QAudioOutput: snd_pcm_hw_params: err = %1").arg(err);
        }
    }
    if( err < 0) {
        qWarning()<<errMessage;
        errorState = QAudio::OpenError;
        deviceState = QAudio::StoppedState;
        return false;
    }
    snd_pcm_hw_params_get_buffer_size(hwparams,&buffer_frames);
    buffer_size = snd_pcm_frames_to_bytes(handle,buffer_frames);
    snd_pcm_hw_params_get_period_size(hwparams,&period_frames, &dir);
    period_size = snd_pcm_frames_to_bytes(handle,period_frames);
    snd_pcm_hw_params_get_buffer_time(hwparams,&buffer_time, &dir);
    snd_pcm_hw_params_get_period_time(hwparams,&period_time, &dir);

    // Step 3: Set the desired SW parameters.
    snd_pcm_sw_params_t *swparams;
    snd_pcm_sw_params_alloca(&swparams);
    snd_pcm_sw_params_current(handle, swparams);
    snd_pcm_sw_params_set_start_threshold(handle,swparams,period_frames);
    snd_pcm_sw_params_set_stop_threshold(handle,swparams,buffer_frames);
    snd_pcm_sw_params_set_avail_min(handle, swparams,period_frames);
    snd_pcm_sw_params(handle, swparams);

    // Step 4: Prepare audio
    if(audioBuffer == 0)
        audioBuffer = new char[snd_pcm_frames_to_bytes(handle,buffer_frames)];
    snd_pcm_prepare( handle );
    snd_pcm_start(handle);

    // Step 5: Setup callback and timer fallback
    snd_async_add_pcm_handler(&ahandler, handle, async_callback, this);
    bytesAvailable = bytesFree();

    // Step 6: Start audio processing
    timer->start(period_time/1000);

    clockStamp.restart();
    timeStamp.restart();
    elapsedTimeOffset = 0;
    errorState  = QAudio::NoError;
    totalTimeValue = 0;
    opened = true;

    return true;
}
示例#30
0
static void *alsa_thread_init(const char *device,
      unsigned rate, unsigned latency)
{
   snd_pcm_uframes_t buffer_size;
   snd_pcm_format_t format;
   snd_pcm_hw_params_t *params    = NULL;
   snd_pcm_sw_params_t *sw_params = NULL;
   const char *alsa_dev           = device ? device : "default";
   unsigned latency_usec          = latency * 1000 / 2;
   unsigned channels              = 2;
   unsigned periods               = 4;
   alsa_thread_t            *alsa = (alsa_thread_t*)
      calloc(1, sizeof(alsa_thread_t));

   if (!alsa)
      return NULL;

   TRY_ALSA(snd_pcm_open(&alsa->pcm, alsa_dev, SND_PCM_STREAM_PLAYBACK, 0));

   TRY_ALSA(snd_pcm_hw_params_malloc(&params));
   alsa->has_float = alsathread_find_float_format(alsa->pcm, params);
   format = alsa->has_float ? SND_PCM_FORMAT_FLOAT : SND_PCM_FORMAT_S16;

   TRY_ALSA(snd_pcm_hw_params_any(alsa->pcm, params));
   TRY_ALSA(snd_pcm_hw_params_set_access(
            alsa->pcm, params, SND_PCM_ACCESS_RW_INTERLEAVED));
   TRY_ALSA(snd_pcm_hw_params_set_format(alsa->pcm, params, format));
   TRY_ALSA(snd_pcm_hw_params_set_channels(alsa->pcm, params, channels));
   TRY_ALSA(snd_pcm_hw_params_set_rate(alsa->pcm, params, rate, 0));

   TRY_ALSA(snd_pcm_hw_params_set_buffer_time_near(
            alsa->pcm, params, &latency_usec, NULL));
   TRY_ALSA(snd_pcm_hw_params_set_periods_near(
            alsa->pcm, params, &periods, NULL));

   TRY_ALSA(snd_pcm_hw_params(alsa->pcm, params));

   /* Shouldn't have to bother with this, 
    * but some drivers are apparently broken. */
   if (snd_pcm_hw_params_get_period_size(params, &alsa->period_frames, NULL))
      snd_pcm_hw_params_get_period_size_min(
            params, &alsa->period_frames, NULL);
   RARCH_LOG("ALSA: Period size: %d frames\n", (int)alsa->period_frames);
   if (snd_pcm_hw_params_get_buffer_size(params, &buffer_size))
      snd_pcm_hw_params_get_buffer_size_max(params, &buffer_size);
   RARCH_LOG("ALSA: Buffer size: %d frames\n", (int)buffer_size);

   alsa->buffer_size = snd_pcm_frames_to_bytes(alsa->pcm, buffer_size);
   alsa->period_size = snd_pcm_frames_to_bytes(alsa->pcm, alsa->period_frames);

   TRY_ALSA(snd_pcm_sw_params_malloc(&sw_params));
   TRY_ALSA(snd_pcm_sw_params_current(alsa->pcm, sw_params));
   TRY_ALSA(snd_pcm_sw_params_set_start_threshold(
            alsa->pcm, sw_params, buffer_size / 2));
   TRY_ALSA(snd_pcm_sw_params(alsa->pcm, sw_params));

   snd_pcm_hw_params_free(params);
   snd_pcm_sw_params_free(sw_params);

   alsa->fifo_lock = slock_new();
   alsa->cond_lock = slock_new();
   alsa->cond = scond_new();
   alsa->buffer = fifo_new(alsa->buffer_size);
   if (!alsa->fifo_lock || !alsa->cond_lock || !alsa->cond || !alsa->buffer)
      goto error;

   alsa->worker_thread = sthread_create(alsa_worker_thread, alsa);
   if (!alsa->worker_thread)
   {
      RARCH_ERR("error initializing worker thread");
      goto error;
   }

   return alsa;

error:
   RARCH_ERR("ALSA: Failed to initialize...\n");
   if (params)
      snd_pcm_hw_params_free(params);

   if (sw_params)
      snd_pcm_sw_params_free(sw_params);

   alsa_thread_free(alsa);

   return NULL;
}