Commit 352b5f93 authored by Jean-Paul Saman's avatar Jean-Paul Saman
Browse files

Make headphone also an audio_filter2

parent 663716c0
......@@ -30,8 +30,10 @@
#include <math.h> /* sqrt */
#include <vlc/vlc.h>
#include "audio_output.h"
#include "aout_internal.h"
#include <audio_output.h>
#include <aout_internal.h>
#include <vlc_filter.h>
#include <vlc_block.h>
/*****************************************************************************
* Local prototypes
......@@ -42,6 +44,11 @@ static void Destroy ( vlc_object_t * );
static void DoWork ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
aout_buffer_t * );
/* Audio filter2 */
static int OpenFilter ( vlc_object_t * );
static void CloseFilter( vlc_object_t * );
static block_t *Convert( filter_t *, block_t * );
/*****************************************************************************
* Module descriptor
*****************************************************************************/
......@@ -85,6 +92,12 @@ vlc_module_begin();
set_capability( "audio filter", 0 );
set_callbacks( Create, Destroy );
add_shortcut( "headphone" );
/* Audio filter 2 */
add_submodule();
set_description( _("Headphone virtual spatialization effect") );
set_capability( "audio filter2", 100 );
set_callbacks( OpenFilter, CloseFilter );
vlc_module_end();
......@@ -107,6 +120,14 @@ struct aout_filter_sys_t
struct atomic_operation_t * p_atomic_operations;
};
struct filter_sys_t
{
size_t i_overflow_buffer_size;/* in bytes */
byte_t * p_overflow_buffer;
unsigned int i_nb_atomic_operations;
struct atomic_operation_t * p_atomic_operations;
};
/*****************************************************************************
* Init: initialize internal data structures
* and computes the needed atomic operations
......@@ -125,10 +146,10 @@ struct aout_filter_sys_t
*
* x-axis
* */
static void ComputeChannelOperations ( struct aout_filter_sys_t * p_data
, unsigned int i_rate , unsigned int i_next_atomic_operation
, int i_source_channel_offset , double d_x , double d_z
, double d_compensation_length , double d_channel_amplitude_factor )
static void ComputeChannelOperations( struct aout_filter_sys_t * p_data
, unsigned int i_rate, unsigned int i_next_atomic_operation
, int i_source_channel_offset, double d_x, double d_z
, double d_compensation_length, double d_channel_amplitude_factor )
{
double d_c = 340; /*sound celerity (unit: m/s)*/
double d_compensation_delay = (d_compensation_length-0.1) / d_c * i_rate;
......@@ -141,12 +162,12 @@ static void ComputeChannelOperations ( struct aout_filter_sys_t * p_data
p_data->p_atomic_operations[i_next_atomic_operation]
.i_delay = (int)( sqrt( (-0.1-d_x)*(-0.1-d_x) + (0-d_z)*(0-d_z) )
/ d_c * i_rate - d_compensation_delay );
if ( d_x < 0 )
if( d_x < 0 )
{
p_data->p_atomic_operations[i_next_atomic_operation]
.d_amplitude_factor = d_channel_amplitude_factor * 1.1 / 2;
}
else if ( d_x > 0 )
else if( d_x > 0 )
{
p_data->p_atomic_operations[i_next_atomic_operation]
.d_amplitude_factor = d_channel_amplitude_factor * 0.9 / 2;
......@@ -165,12 +186,12 @@ static void ComputeChannelOperations ( struct aout_filter_sys_t * p_data
p_data->p_atomic_operations[i_next_atomic_operation + 1]
.i_delay = (int)( sqrt( (0.1-d_x)*(0.1-d_x) + (0-d_z)*(0-d_z) )
/ d_c * i_rate - d_compensation_delay );
if ( d_x < 0 )
if( d_x < 0 )
{
p_data->p_atomic_operations[i_next_atomic_operation + 1]
.d_amplitude_factor = d_channel_amplitude_factor * 0.9 / 2;
}
else if ( d_x > 0 )
else if( d_x > 0 )
{
p_data->p_atomic_operations[i_next_atomic_operation + 1]
.d_amplitude_factor = d_channel_amplitude_factor * 1.1 / 2;
......@@ -182,11 +203,11 @@ static void ComputeChannelOperations ( struct aout_filter_sys_t * p_data
}
}
static int Init ( aout_filter_t * p_filter , struct aout_filter_sys_t * p_data
, unsigned int i_nb_channels , uint32_t i_physical_channels
static int Init( vlc_object_t *p_this, struct aout_filter_sys_t * p_data
, unsigned int i_nb_channels, uint32_t i_physical_channels
, unsigned int i_rate )
{
double d_x = config_GetInt ( p_filter , "headphone-dim" );
double d_x = config_GetInt( p_this, "headphone-dim" );
double d_z = d_x;
double d_z_rear = -d_x/3;
double d_min = 0;
......@@ -194,16 +215,16 @@ static int Init ( aout_filter_t * p_filter , struct aout_filter_sys_t * p_data
int i_source_channel_offset;
unsigned int i;
if ( p_data == NULL )
if( p_data == NULL )
{
msg_Dbg ( p_filter, "passing a null pointer as argument" );
msg_Dbg( p_this, "passing a null pointer as argument" );
return 0;
}
if ( config_GetInt ( p_filter , "headphone-compensate" ) )
if( config_GetInt( p_this, "headphone-compensate" ) )
{
/* minimal distance to any speaker */
if ( i_physical_channels & AOUT_CHAN_REARCENTER )
if( i_physical_channels & AOUT_CHAN_REARCENTER )
{
d_min = d_z_rear;
}
......@@ -215,15 +236,15 @@ static int Init ( aout_filter_t * p_filter , struct aout_filter_sys_t * p_data
/* Number of elementary operations */
p_data->i_nb_atomic_operations = i_nb_channels * 2;
if ( i_physical_channels & AOUT_CHAN_CENTER )
if( i_physical_channels & AOUT_CHAN_CENTER )
{
p_data->i_nb_atomic_operations += 2;
}
p_data->p_atomic_operations = malloc ( sizeof(struct atomic_operation_t)
p_data->p_atomic_operations = malloc( sizeof(struct atomic_operation_t)
* p_data->i_nb_atomic_operations );
if ( p_data->p_atomic_operations == NULL )
if( p_data->p_atomic_operations == NULL )
{
msg_Err( p_filter, "out of memory" );
msg_Err( p_this, "out of memory" );
return -1;
}
......@@ -231,78 +252,78 @@ static int Init ( aout_filter_t * p_filter , struct aout_filter_sys_t * p_data
* to each ear */
i_next_atomic_operation = 0;
i_source_channel_offset = 0;
if ( i_physical_channels & AOUT_CHAN_LEFT )
if( i_physical_channels & AOUT_CHAN_LEFT )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, -d_x , d_z , d_min , 2.0 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_RIGHT )
if( i_physical_channels & AOUT_CHAN_RIGHT )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, d_x , d_z , d_min , 2.0 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_MIDDLELEFT )
if( i_physical_channels & AOUT_CHAN_MIDDLELEFT )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, -d_x , 0 , d_min , 1.5 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_MIDDLERIGHT )
if( i_physical_channels & AOUT_CHAN_MIDDLERIGHT )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, d_x , 0 , d_min , 1.5 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_REARLEFT )
if( i_physical_channels & AOUT_CHAN_REARLEFT )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, -d_x , d_z_rear , d_min , 1.5 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_REARRIGHT )
if( i_physical_channels & AOUT_CHAN_REARRIGHT )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, d_x , d_z_rear , d_min , 1.5 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_REARCENTER )
if( i_physical_channels & AOUT_CHAN_REARCENTER )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, 0 , -d_z , d_min , 1.5 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_CENTER )
if( i_physical_channels & AOUT_CHAN_CENTER )
{
/* having two center channels increases the spatialization effect */
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, d_x / 5.0 , d_z , d_min , 0.75 / i_nb_channels );
i_next_atomic_operation += 2;
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, -d_x / 5.0 , d_z , d_min , 0.75 / i_nb_channels );
i_next_atomic_operation += 2;
i_source_channel_offset++;
}
if ( i_physical_channels & AOUT_CHAN_LFE )
if( i_physical_channels & AOUT_CHAN_LFE )
{
ComputeChannelOperations ( p_data , i_rate
ComputeChannelOperations( p_data , i_rate
, i_next_atomic_operation , i_source_channel_offset
, 0 , d_z_rear , d_min , 5.0 / i_nb_channels );
i_next_atomic_operation += 2;
......@@ -312,22 +333,22 @@ static int Init ( aout_filter_t * p_filter , struct aout_filter_sys_t * p_data
/* Initialize the overflow buffer
* we need it because the process induce a delay in the samples */
p_data->i_overflow_buffer_size = 0;
for ( i = 0 ; i < p_data->i_nb_atomic_operations ; i++ )
for( i = 0 ; i < p_data->i_nb_atomic_operations ; i++ )
{
if ( p_data->i_overflow_buffer_size
if( p_data->i_overflow_buffer_size
< p_data->p_atomic_operations[i].i_delay * 2 * sizeof (float) )
{
p_data->i_overflow_buffer_size
= p_data->p_atomic_operations[i].i_delay * 2 * sizeof (float);
}
}
p_data->p_overflow_buffer = malloc ( p_data->i_overflow_buffer_size );
if ( p_data->p_atomic_operations == NULL )
p_data->p_overflow_buffer = malloc( p_data->i_overflow_buffer_size );
if( p_data->p_atomic_operations == NULL )
{
msg_Err( p_filter, "out of memory" );
msg_Err( p_this, "out of memory" );
return -1;
}
memset ( p_data->p_overflow_buffer , 0 , p_data->i_overflow_buffer_size );
memset( p_data->p_overflow_buffer, 0 , p_data->i_overflow_buffer_size );
/* end */
return 0;
......@@ -342,7 +363,7 @@ static int Create( vlc_object_t *p_this )
vlc_bool_t b_fit = VLC_TRUE;
/* Activate this filter only with stereo devices */
if ( p_filter->output.i_physical_channels
if( p_filter->output.i_physical_channels
!= (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT) )
{
msg_Dbg( p_filter, "filter discarded (incompatible format)" );
......@@ -350,26 +371,26 @@ static int Create( vlc_object_t *p_this )
}
/* Request a specific format if not already compatible */
if ( p_filter->input.i_original_channels
if( p_filter->input.i_original_channels
!= p_filter->output.i_original_channels )
{
b_fit = VLC_FALSE;
p_filter->input.i_original_channels =
p_filter->output.i_original_channels;
}
if ( p_filter->input.i_format != VLC_FOURCC('f','l','3','2')
if( p_filter->input.i_format != VLC_FOURCC('f','l','3','2')
|| p_filter->output.i_format != VLC_FOURCC('f','l','3','2') )
{
b_fit = VLC_FALSE;
p_filter->input.i_format = VLC_FOURCC('f','l','3','2');
p_filter->output.i_format = VLC_FOURCC('f','l','3','2');
}
if ( p_filter->input.i_rate != p_filter->output.i_rate )
if( p_filter->input.i_rate != p_filter->output.i_rate )
{
b_fit = VLC_FALSE;
p_filter->input.i_rate = p_filter->output.i_rate;
}
if ( p_filter->input.i_physical_channels == (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT)
if( p_filter->input.i_physical_channels == (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT)
&& ( p_filter->input.i_original_channels & AOUT_CHAN_DOLBYSTEREO )
&& ! config_GetInt ( p_filter , "headphone-dolby" ) )
{
......@@ -379,7 +400,7 @@ static int Create( vlc_object_t *p_this )
AOUT_CHAN_REARLEFT |
AOUT_CHAN_REARRIGHT;
}
if ( ! b_fit )
if( ! b_fit )
{
msg_Dbg( p_filter, "requesting specific format" );
return VLC_EGENERIC;
......@@ -387,7 +408,7 @@ static int Create( vlc_object_t *p_this )
/* Allocate the memory needed to store the module's structure */
p_filter->p_sys = malloc( sizeof(struct aout_filter_sys_t) );
if ( p_filter->p_sys == NULL )
if( p_filter->p_sys == NULL )
{
msg_Err( p_filter, "out of memory" );
return VLC_EGENERIC;
......@@ -397,7 +418,7 @@ static int Create( vlc_object_t *p_this )
p_filter->p_sys->i_nb_atomic_operations = 0;
p_filter->p_sys->p_atomic_operations = NULL;
if ( Init( p_filter , p_filter->p_sys
if( Init( VLC_OBJECT(p_filter), p_filter->p_sys
, aout_FormatNbChannels ( &p_filter->input )
, p_filter->input.i_physical_channels
, p_filter->input.i_rate ) < 0 )
......@@ -418,17 +439,17 @@ static void Destroy( vlc_object_t *p_this )
{
aout_filter_t * p_filter = (aout_filter_t *)p_this;
if ( p_filter->p_sys != NULL )
if( p_filter->p_sys != NULL )
{
if ( p_filter->p_sys->p_overflow_buffer != NULL )
if( p_filter->p_sys->p_overflow_buffer != NULL )
{
free ( p_filter->p_sys->p_overflow_buffer );
free( p_filter->p_sys->p_overflow_buffer );
}
if ( p_filter->p_sys->p_atomic_operations != NULL )
if( p_filter->p_sys->p_atomic_operations != NULL )
{
free ( p_filter->p_sys->p_atomic_operations );
free( p_filter->p_sys->p_atomic_operations );
}
free ( p_filter->p_sys );
free( p_filter->p_sys );
p_filter->p_sys = NULL;
}
}
......@@ -457,46 +478,45 @@ static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
unsigned int i_delay;
double d_amplitude_factor;
/* out buffer characterisitcs */
p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * i_output_nb / i_input_nb;
p_out = p_out_buf->p_buffer;
i_out_size = p_out_buf->i_nb_bytes;
if ( p_filter->p_sys != NULL )
if( p_filter->p_sys != NULL )
{
/* Slide the overflow buffer */
p_overflow = p_filter->p_sys->p_overflow_buffer;
i_overflow_size = p_filter->p_sys->i_overflow_buffer_size;
memset ( p_out , 0 , i_out_size );
memset( p_out, 0, i_out_size );
if ( i_out_size > i_overflow_size )
memcpy ( p_out , p_overflow , i_overflow_size );
memcpy( p_out, p_overflow, i_overflow_size );
else
memcpy ( p_out , p_overflow , i_out_size );
memcpy( p_out, p_overflow, i_out_size );
p_slide = p_filter->p_sys->p_overflow_buffer;
while ( p_slide < p_overflow + i_overflow_size )
while( p_slide < p_overflow + i_overflow_size )
{
if ( p_slide + i_out_size < p_overflow + i_overflow_size )
if( p_slide + i_out_size < p_overflow + i_overflow_size )
{
memset ( p_slide , 0 , i_out_size );
if ( p_slide + 2 * i_out_size < p_overflow + i_overflow_size )
memcpy ( p_slide , p_slide + i_out_size , i_out_size );
memset( p_slide, 0, i_out_size );
if( p_slide + 2 * i_out_size < p_overflow + i_overflow_size )
memcpy( p_slide, p_slide + i_out_size, i_out_size );
else
memcpy ( p_slide , p_slide + i_out_size
, p_overflow + i_overflow_size - ( p_slide + i_out_size ) );
memcpy( p_slide, p_slide + i_out_size,
p_overflow + i_overflow_size - ( p_slide + i_out_size ) );
}
else
{
memset ( p_slide , 0 , p_overflow + i_overflow_size - p_slide );
memset( p_slide, 0, p_overflow + i_overflow_size - p_slide );
}
p_slide += i_out_size;
}
/* apply the atomic operations */
for ( i = 0 ; i < p_filter->p_sys->i_nb_atomic_operations ; i++ )
for( i = 0; i < p_filter->p_sys->i_nb_atomic_operations; i++ )
{
/* shorter variable names */
i_source_channel_offset
......@@ -507,10 +527,10 @@ static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
d_amplitude_factor
= p_filter->p_sys->p_atomic_operations[i].d_amplitude_factor;
if ( p_out_buf->i_nb_samples > i_delay )
if( p_out_buf->i_nb_samples > i_delay )
{
/* current buffer coefficients */
for ( j = 0 ; j < p_out_buf->i_nb_samples - i_delay ; j++ )
for( j = 0; j < p_out_buf->i_nb_samples - i_delay; j++ )
{
((float*)p_out)[ (i_delay+j)*i_output_nb + i_dest_channel_offset ]
+= p_in[ j * i_input_nb + i_source_channel_offset ]
......@@ -518,7 +538,7 @@ static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
}
/* overflow buffer coefficients */
for ( j = 0 ; j < i_delay ; j++ )
for( j = 0; j < i_delay; j++ )
{
((float*)p_overflow)[ j*i_output_nb + i_dest_channel_offset ]
+= p_in[ (p_out_buf->i_nb_samples - i_delay + j)
......@@ -529,7 +549,7 @@ static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
else
{
/* overflow buffer coefficients only */
for ( j = 0 ; j < p_out_buf->i_nb_samples ; j++ )
for( j = 0; j < p_out_buf->i_nb_samples; j++ )
{
((float*)p_overflow)[ (i_delay - p_out_buf->i_nb_samples + j)
* i_output_nb + i_dest_channel_offset ]
......@@ -541,6 +561,165 @@ static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
}
else
{
memset ( p_out , 0 , i_out_size );
memset( p_out, 0, i_out_size );
}
}
/*
* Audio filter 2
*/
/*****************************************************************************
* OpenFilter:
*****************************************************************************/
static int OpenFilter( vlc_object_t *p_this )
{
filter_t *p_filter = (filter_t *)p_this;
vlc_bool_t b_fit = VLC_TRUE;
/* Activate this filter only with stereo devices */
if( p_filter->fmt_out.audio.i_physical_channels
!= (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT) )
{
msg_Dbg( p_filter, "filter discarded (incompatible format)" );
return VLC_EGENERIC;
}
/* Request a specific format if not already compatible */
if( p_filter->fmt_in.audio.i_original_channels
!= p_filter->fmt_out.audio.i_original_channels )
{
b_fit = VLC_FALSE;
p_filter->fmt_in.audio.i_original_channels =
p_filter->fmt_out.audio.i_original_channels;
}
if( p_filter->fmt_in.audio.i_format != VLC_FOURCC('f','l','3','2')
|| p_filter->fmt_out.audio.i_format != VLC_FOURCC('f','l','3','2') )
{
b_fit = VLC_FALSE;
p_filter->fmt_in.audio.i_format = VLC_FOURCC('f','l','3','2');
p_filter->fmt_out.audio.i_format = VLC_FOURCC('f','l','3','2');
}
if( p_filter->fmt_in.audio.i_rate != p_filter->fmt_out.audio.i_rate )
{
b_fit = VLC_FALSE;
p_filter->fmt_in.audio.i_rate = p_filter->fmt_out.audio.i_rate;
}
if( p_filter->fmt_in.audio.i_physical_channels == (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT)
&& ( p_filter->fmt_in.audio.i_original_channels & AOUT_CHAN_DOLBYSTEREO )
&& !config_GetInt( p_filter, "headphone-dolby" ) )
{
b_fit = VLC_FALSE;
p_filter->fmt_in.audio.i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
AOUT_CHAN_CENTER |
AOUT_CHAN_REARLEFT |
AOUT_CHAN_REARRIGHT;
}
if( !b_fit )
{
msg_Dbg( p_filter, "requesting specific format" );
return VLC_EGENERIC;
}
/* Allocate the memory needed to store the module's structure */
p_filter->p_sys = malloc( sizeof(struct filter_sys_t) );
if( p_filter->p_sys == NULL )
{
msg_Err( p_filter, "out of memory" );
return VLC_EGENERIC;
}
p_filter->p_sys->i_overflow_buffer_size = 0;
p_filter->p_sys->p_overflow_buffer = NULL;
p_filter->p_sys->i_nb_atomic_operations = 0;
p_filter->p_sys->p_atomic_operations = NULL;
if( Init( VLC_OBJECT(p_filter), (struct aout_filter_sys_t *)p_filter->p_sys
, aout_FormatNbChannels ( &(p_filter->fmt_in.audio) )
, p_filter->fmt_in.audio.i_physical_channels
, p_filter->fmt_in.audio.i_rate ) < 0 )
{
return VLC_EGENERIC;
}
p_filter->pf_audio_filter = Convert;
p_filter->fmt_out.audio.i_rate = p_filter->fmt_in.audio.i_rate;
msg_Dbg( p_this, ">> HEADPHONE filter loaded" );
return VLC_SUCCESS;
}
/*****************************************************************************
* CloseFilter : deallocate data structures
*****************************************************************************/
static void CloseFilter( vlc_object_t *p_this )
{
filter_t *p_filter = (filter_t *)p_this;
filter_sys_t *p_sys = p_filter->p_sys;
if( p_filter->p_sys != NULL )
{
if( p_filter->p_sys->p_overflow_buffer != NULL )
{
free ( p_filter->p_sys->p_overflow_buffer );
}
if( p_filter->p_sys->p_atomic_operations != NULL )
{
free ( p_filter->p_sys->p_atomic_operations );
}
free( p_filter->p_sys );
p_filter->p_sys = NULL;
}
if( p_sys) free( p_sys );
}
static block_t *Convert( filter_t *p_filter, block_t *p_block )
{
aout_filter_t aout_filter;
aout_buffer_t in_buf, out_buf;
block_t *p_out;
int i_out_size;
if( !p_block || !p_block->i_samples )
{
if( p_block ) p_block->pf_release( p_block );
return NULL;
}
i_out_size = p_block->i_samples *
p_filter->fmt_out.audio.i_bitspersample *
p_filter->fmt_out.audio.i_channels / 8;
p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
if( !p_out )
{
msg_Warn( p_filter, "can't get output buffer" );
if( p_block ) p_block->pf_release( p_block );
return NULL;
}
p_out->i_samples = p_block->i_samples;
p_out->i_dts = p_block->i_dts;
p_out->i_pts = p_block->i_pts;
p_out->i_length = p_block->i_length;
aout_filter.p_sys = (struct aout_filter_sys_t *)