int enclameInit( hb_work_object_t * w, hb_job_t * job )
{
hb_work_private_t * pv = calloc( 1, sizeof( hb_work_private_t ) );
hb_audio_t * audio = w->audio;
w->private_data = pv;
pv->job = job;
hb_log( "enclame: opening libmp3lame" );
pv->lame = lame_init();
// use ABR
lame_set_scale( pv->lame, 32768.0 );
if( audio->config.out.compression_level >= 0 )
{
lame_set_quality( pv->lame, audio->config.out.compression_level );
}
if( audio->config.out.bitrate > 0 )
{
lame_set_VBR( pv->lame, vbr_abr );
lame_set_VBR_mean_bitrate_kbps( pv->lame, audio->config.out.bitrate );
}
else if( audio->config.out.quality >= 0 )
{
lame_set_brate( pv->lame, 0 );
lame_set_VBR( pv->lame, vbr_default );
lame_set_VBR_quality( pv->lame, audio->config.out.quality );
}
lame_set_in_samplerate( pv->lame, audio->config.out.samplerate );
lame_set_out_samplerate( pv->lame, audio->config.out.samplerate );
pv->out_discrete_channels = hb_mixdown_get_discrete_channel_count( audio->config.out.mixdown );
// Lame's default encoding mode is JOINT_STEREO. This subtracts signal
// that is "common" to left and right (within some threshold) and encodes
// it separately. This improves quality at low bitrates, but hurts
// imaging (channel separation) at higher bitrates. So if the bitrate
// is suffeciently high, use regular STEREO mode.
if ( pv->out_discrete_channels == 1 )
{
lame_set_mode( pv->lame, MONO );
lame_set_num_channels( pv->lame, 1 );
}
else if ( audio->config.out.bitrate >= 128 )
{
lame_set_mode( pv->lame, STEREO );
}
lame_init_params( pv->lame );
pv->input_samples = 1152 * pv->out_discrete_channels;
pv->output_bytes = LAME_MAXMP3BUFFER;
pv->buf = malloc( pv->input_samples * sizeof( float ) );
audio->config.out.samples_per_frame = 1152;
pv->list = hb_list_init();
pv->pts = -1;
return 0;
}
void lame_encoder_impl_internal::set_scale(float _Scale)
{
int lameRet = lame_set_scale(m_Lame.get(), _Scale);
DT_LAME_CHECK_ERR(lameRet);
}