[vlc-devel] [PATCH 1/2] Add new API to libvlc for persistent equalizer settings.

Rémi Denis-Courmont remi at remlab.net
Sun Aug 12 10:47:35 CEST 2012


Le dimanche 12 août 2012 11:30:45 Mark Lee, vous avez écrit :
>  /** @} media_player */
> diff --git a/lib/audio.c b/lib/audio.c
> index 27d7cd4..8e7b959 100644
> --- a/lib/audio.c
> +++ b/lib/audio.c
> @@ -42,6 +42,8 @@
>  #include "libvlc_internal.h"
>  #include "media_player_internal.h"
> 
> +#include "modules/audio_filter/equalizer_presets.h"
> +
>  /*
>   * Remember to release the returned audio_output_t since it is locked at
>   * the end of this function.
> @@ -507,3 +509,153 @@ int libvlc_audio_set_delay( libvlc_media_player_t
> *p_mi, int64_t i_delay ) }
>      return ret;
>  }
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_get_preset_count : Get the number of
> equalizer presets +
> **************************************************************************
> ***/ +unsigned libvlc_audio_equalizer_get_preset_count( void )
> +{
> +    return NB_PRESETS;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_get_preset_name : Get the name for a preset
> +
> **************************************************************************
> ***/ +const char *libvlc_audio_equalizer_get_preset_name( int i_index ) +{
> +    if ( i_index < 0 || i_index >= NB_PRESETS )
> +        return NULL;

You should use unsigned for consistency with ..._count and to simplify.

> +
> +    return preset_list_text[ i_index ];
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_get_band_count : Get the number of
> equalizer frequency bands +
> **************************************************************************
> ***/ +unsigned libvlc_audio_equalizer_get_band_count( void )
> +{
> +    return EQZ_BANDS_MAX;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_get_band_frequency : Get the frequency for
> a band +
> **************************************************************************
> ***/ +float libvlc_audio_equalizer_get_band_frequency( int i_index )
> +{
> +    if ( i_index < 0 || i_index >= EQZ_BANDS_MAX )
> +        return -1;
> +
> +    return f_vlc_frequency_table_10b[ i_index ];
> +}

Same here and later.

> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_new : Create a new audio equalizer with
> zeroed values +
> **************************************************************************
> ***/ +libvlc_equalizer_t *libvlc_audio_equalizer_new( void )
> +{
> +    libvlc_equalizer_t *p_equalizer;
> +
> +    p_equalizer = malloc( sizeof( *p_equalizer ) );
> +    if ( p_equalizer == NULL )
> +        return NULL;
> +
> +    p_equalizer->f_preamp = 0.0;
> +
> +    for ( int i = 0; i < EQZ_BANDS_MAX; i++ )
> +        p_equalizer->f_amp[ i ] = 0.0;
> +
> +    return p_equalizer;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_new_from_preset : Create a new audio
> equalizer based on a preset +
> **************************************************************************
> ***/ +libvlc_equalizer_t *libvlc_audio_equalizer_new_from_preset( int
> i_index ) +{
> +    libvlc_equalizer_t *p_equalizer;
> +
> +    if ( i_index < 0 || i_index >= NB_PRESETS )
> +        return NULL;
> +
> +    p_equalizer = libvlc_audio_equalizer_new();
> +    if ( !p_equalizer )
> +        return NULL;
> +
> +    p_equalizer->f_preamp = eqz_preset_10b[ i_index ].f_preamp;
> +
> +    for ( int i = 0; i < EQZ_BANDS_MAX; i++ )
> +        p_equalizer->f_amp[ i ] = eqz_preset_10b[ i_index ].f_amp[ i ];
> +
> +    return p_equalizer;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_release : Release a previously created
> equalizer +
> **************************************************************************
> ***/ +void libvlc_audio_equalizer_release( libvlc_equalizer_t *p_equalizer
> ) +{
> +    if ( p_equalizer )
> +        free( p_equalizer );

if() is not needed. Refer to ISO C.

> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_set_preamp : Set the preamp value for an
> equalizer +
> **************************************************************************
> ***/ +int libvlc_audio_equalizer_set_preamp( libvlc_equalizer_t
> *p_equalizer, float f_preamp ) +{
> +    if ( !p_equalizer )
> +        return -1;
> +
> +    if ( f_preamp < -20.0 )

Use 'f' postfix to avoid conversions to/from double.

> +        f_preamp = -20.0;
> +    else if ( f_preamp > 20.0 )
> +        f_preamp = 20.0;
> +
> +    p_equalizer->f_preamp = f_preamp;
> +    return 0;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_get_preamp : Get the preamp value for an
> equalizer +
> **************************************************************************
> ***/ +float libvlc_audio_equalizer_get_preamp( libvlc_equalizer_t
> *p_equalizer ) +{
> +    if ( !p_equalizer )
> +        return 0;

0.f would be more consistent.

> +
> +    return p_equalizer->f_preamp;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_set_amp_at_index : Set the amplification
> value for an equalizer band +
> **************************************************************************
> ***/ +int libvlc_audio_equalizer_set_amp_at_index( libvlc_equalizer_t
> *p_equalizer, float f_amp, int i_band ) +{
> +    if ( !p_equalizer )
> +        return -1;
> +
> +    if ( i_band < 0 || i_band >= EQZ_BANDS_MAX )
> +        return -1;
> +
> +    if ( f_amp < -20.0 )
> +        f_amp = -20.0;
> +    else if ( f_amp > 20.0 )
> +        f_amp = 20.0;
> +
> +    p_equalizer->f_amp[ i_band ] = f_amp;
> +    return 0;
> +}
> +
> +/*************************************************************************
> **** + * libvlc_audio_equalizer_get_amp_at_index : Get the amplification
> value for an equalizer band +
> **************************************************************************
> ***/ +float libvlc_audio_equalizer_get_amp_at_index( libvlc_equalizer_t
> *p_equalizer, int i_band ) +{
> +    if ( !p_equalizer )
> +        return 0;
> +
> +    if ( i_band < 0 || i_band >= EQZ_BANDS_MAX )
> +        return 0;
> +
> +    return p_equalizer->f_amp[ i_band ];
> +}

> diff --git a/lib/media_player.c b/lib/media_player.c
> index a41b8c7..f2cb46d 100644
> --- a/lib/media_player.c
> +++ b/lib/media_player.c
> @@ -34,11 +34,14 @@
>  #include <vlc_input.h>
>  #include <vlc_vout.h>
>  #include <vlc_keys.h>
> +#include <vlc_aout_intf.h>
> 
>  #include "libvlc_internal.h"
>  #include "media_internal.h" // libvlc_media_set_state()
>  #include "media_player_internal.h"
> 
> +#include "modules/audio_filter/equalizer_presets.h"
> +
>  /*
>   * mapping of libvlc_navigate_mode_t to vlc_action_t
>   */
> @@ -482,6 +485,9 @@ libvlc_media_player_new( libvlc_instance_t *instance )
>      var_Create (mp, "amem-rate", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT);
>      var_Create (mp, "amem-channels", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT);
> 
> +    var_Create (mp, "equalizer-preamp", VLC_VAR_FLOAT );
> +    var_Create (mp, "equalizer-bands", VLC_VAR_STRING  );
> +
>      mp->p_md = NULL;
>      mp->state = libvlc_NothingSpecial;
>      mp->p_libvlc_instance = instance;
> @@ -1409,3 +1415,49 @@ void libvlc_media_player_next_frame(
> libvlc_media_player_t *p_mi ) vlc_object_release( p_input_thread );
>      }
>  }
> +
> +int libvlc_media_player_set_equalizer( libvlc_media_player_t *p_mi,
> libvlc_equalizer_t *p_equalizer )
> +{
> +    if ( !p_mi )
> +        return -1;

Is this useful to check in practice?

> +
> +    p_mi->p_equalizer = p_equalizer;
> +
> +    if ( p_equalizer )
> +    {
> +        aout_EnableFilter( p_mi, "equalizer", true );
> +
> +        var_SetFloat( p_mi, "equalizer-preamp", p_equalizer->f_preamp );
> +
> +        // This implementation slightly adapted from
> modules/audio_filter/equalizer.c
> +        char *psz_bands = NULL;
> +        for ( int i = 0; i < EQZ_BANDS_MAX; i++ )
> +        {
> +            lldiv_t d;
> +            char *psz;
> +
> +            d = lldiv( p_equalizer->f_amp[i] * 10000000, 10000000 );
> +            if ( asprintf( &psz, "%s %lld.%07llu", psz_bands ? psz_bands :
> "", d.quot, d.rem ) == -1 )

Does plain %f not work?

> +            {
> +                free( psz_bands );
> +                return -1;
> +            }
> +            free( psz_bands );
> +            psz_bands = psz;
> +        }
> +        var_SetString( p_mi, "equalizer-bands", psz_bands );
> +        free( psz_bands );
> +    }
> +    else
> +        aout_EnableFilter( p_mi, "equalizer", false );
> +
> +    return 0;
> +}
> +
> +libvlc_equalizer_t *libvlc_media_player_get_equalizer(
> libvlc_media_player_t *p_mi ) +{
> +    if ( !p_mi )
> +        return NULL;
> +
> +    return p_mi->p_equalizer;
> +}

> diff --git a/src/audio_output/common.c b/src/audio_output/common.c
> index c50883b..25f6ad0 100644
> --- a/src/audio_output/common.c
> +++ b/src/audio_output/common.c
> @@ -88,6 +88,9 @@ audio_output_t *aout_New( vlc_object_t * p_parent )
>      var_Create (aout, "mute", VLC_VAR_BOOL | VLC_VAR_DOINHERIT);
>      var_AddCallback (aout, "mute", var_Copy, p_parent);
> 
> +    var_AddCallback (p_parent, "equalizer-preamp", var_Copy, aout );
> +    var_AddCallback (p_parent, "equalizer-bands", var_Copy, aout );
> +

You need to ensure the aout variables exist, and initialized, to do that.

>      /* Visualizations */
>      var_Create (aout, "visual", VLC_VAR_STRING | VLC_VAR_HASCHOICE);
>      text.psz_string = _("Visualizations");
> @@ -197,6 +200,10 @@ void aout_Destroy (audio_output_t *aout)
>      var_DelCallback (aout, "mute", var_Copy, aout->p_parent);
>      var_SetFloat (aout, "volume", -1.f);
>      var_DelCallback (aout, "volume", var_Copy, aout->p_parent);
> +
> +    var_DelCallback (aout->p_parent, "equalizer-bands", var_Copy, aout);
> +    var_DelCallback (aout->p_parent, "equalizer-preamp", var_Copy, aout);
> +
>      vlc_object_release (aout);
>  }


-- 
Rémi Denis-Courmont
C/C++ software engineer looking for a job
http://www.linkedin.com/in/remidenis



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