+/*****************************************************************************
+ * equalizer.c:
+ *****************************************************************************
+ * Copyright (C) 2004 VideoLAN
+ * $Id: goom.c 8019 2004-06-22 19:35:01Z fenrir $
+ *
+ * Authors: Laurent Aimar <fenrir@via.ecp.fr>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+#include <stdlib.h> /* malloc(), free() */
+#include <math.h>
+
+#include <vlc/vlc.h>
+
+#include <vlc/aout.h>
+#include "aout_internal.h"
+
+/* TODO:
+ * - add tables for other rates ( 22500, 11250, ...)
+ * - optimize a bit (you can hardly do slower ;)
+ * - add tables for more bands (15 and 32 would be cool), maybe with auto coeffs
+ * computation (not too hard once the Q is found).
+ * - support for external preset
+ * - callback to handle preset changes on the fly
+ * - ...
+ */
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+static int Open ( vlc_object_t * );
+static void Close( vlc_object_t * );
+
+#define PRESET_TEXT N_( "Equalizer preset" )
+#define PRESET_LONGTEXT PRESET_TEXT
+
+#define BANDS_TEXT N_( "Bands gain")
+#define BANDS_LONGTEXT N_( "Override preset bands gain in dB (-20 ... 20)" )
+
+#define TWOPASS_TEXT N_( "Two pass" )
+#define TWOPASS_LONGTEXT N_( "Filter twice the audio" )
+
+#define PREAMP_TEXT N_("Global gain" )
+#define PREAMP_LONGTEXT N_("Set the global gain in dB (-20 ... 20)" )
+
+static char *preset_list[] = {
+ "flat", "classical", "club", "dance", "fullbass", "fullbasstreeble",
+ "fulltreeble", "headphones","largehall", "live", "party", "pop", "reggae",
+ "rock", "ska", "soft", "softrock", "techno"
+};
+static char *preset_list_text[] = {
+ N_("Flat"), N_("Classical"), N_("Club"), N_("Dance"), N_("Full bass"),
+ N_("Full bass and treeble"), N_("Full treeble"), N_("Laptop speakers and Headphones"),
+ N_("Large Hall"), N_("Live"), N_("Party"), N_("Pop"), N_("Reggae"),
+ N_("Rock"), N_("Ska"), N_("Soft"), N_("Soft rock"), N_("Techno"),
+};
+
+vlc_module_begin();
+ set_description( _("Equalizer 10 bands") );
+ set_capability( "audio filter", 0 );
+ add_string( "equalizer-preset", "flat", NULL, PRESET_TEXT, PRESET_LONGTEXT, VLC_TRUE );
+ change_string_list( preset_list, preset_list_text, 0 );
+ add_string( "equalizer-bands", NULL, NULL, BANDS_TEXT, BANDS_LONGTEXT, VLC_TRUE );
+ add_bool( "equalizer-2pass", 0, NULL, TWOPASS_TEXT, TWOPASS_LONGTEXT, VLC_TRUE );
+ add_float( "equalizer-preamp", 0.0, NULL, PREAMP_TEXT, PREAMP_LONGTEXT, VLC_TRUE );
+ set_callbacks( Open, Close );
+ add_shortcut( "equalizer" );
+vlc_module_end();
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+
+typedef struct aout_filter_sys_t
+{
+ /* Filter static config */
+ int i_band;
+ float *f_alpha;
+ float *f_beta;
+ float *f_gamma;
+
+ /* Filter dyn config */
+ float *f_amp; /* Per band amp */
+ float f_gamp; /* Global preamp */
+ vlc_bool_t b_2eqz;
+
+ /* Filter state */
+ float x[32][2];
+ float y[32][128][2];
+
+ /* Second filter state */
+ float x2[32][2];
+ float y2[32][128][2];
+
+} aout_filter_sys_t;
+
+static void DoWork( aout_instance_t *, aout_filter_t *,
+ aout_buffer_t *, aout_buffer_t * );
+
+#define EQZ_IN_FACTOR (0.25)
+static int EqzInit( aout_filter_t *, int i_rate );
+static void EqzFilter( aout_filter_t *, float *out, float *in, int i_samples, int i_channels );
+static void EqzClean( aout_filter_t * );
+
+/*****************************************************************************
+ * Open:
+ *****************************************************************************/
+static int Open( vlc_object_t *p_this )
+{
+ aout_filter_t *p_filter = (aout_filter_t *)p_this;
+ aout_filter_sys_t *p_sys;
+
+ if( p_filter->input.i_format != VLC_FOURCC('f','l','3','2' ) ||
+ p_filter->output.i_format != VLC_FOURCC('f','l','3','2') )
+ {
+ msg_Warn( p_filter, "Bad input or output format" );
+ return VLC_EGENERIC;
+ }
+ if ( !AOUT_FMTS_SIMILAR( &p_filter->input, &p_filter->output ) )
+ {
+ msg_Warn( p_filter, "input and output formats are not similar" );
+ return VLC_EGENERIC;
+ }
+
+ p_filter->pf_do_work = DoWork;
+ p_filter->b_in_place = VLC_TRUE;
+
+ /* Allocate structure */
+ p_sys = p_filter->p_sys = malloc( sizeof( aout_filter_sys_t ) );
+
+ if( EqzInit( p_filter, p_filter->input.i_rate ) )
+ return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+}
+
+/*****************************************************************************
+ * Close: close the plugin
+ *****************************************************************************/
+static void Close( vlc_object_t *p_this )
+{
+ aout_filter_t *p_filter = (aout_filter_t *)p_this;
+ aout_filter_sys_t *p_sys = p_filter->p_sys;
+
+ EqzClean( p_filter );
+ free( p_sys );
+}
+
+/*****************************************************************************
+ * DoWork: process samples buffer
+ *****************************************************************************
+ *
+ *****************************************************************************/
+static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
+ aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
+{
+ p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
+ p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes;
+
+ EqzFilter( p_filter, (float*)p_out_buf->p_buffer, (float*)p_in_buf->p_buffer,
+ p_in_buf->i_nb_samples, aout_FormatNbChannels( &p_filter->input ) );
+}
+
+/*****************************************************************************
+ * Equalizer stuff
+ *****************************************************************************/
+typedef struct
+{
+ int i_band;
+
+ struct
+ {
+ float f_frequency;
+ float f_alpha;
+ float f_beta;
+ float f_gamma;
+ } band[];
+} eqz_config_t;
+
+/* Value from equ-xmms */
+static const eqz_config_t eqz_config_44100_10b =
+{
+ 10,
+ {
+ { 60, 0.003013, 0.993973, 1.993901 },
+ { 170, 0.008490, 0.983019, 1.982437 },
+ { 310, 0.015374, 0.969252, 1.967331 },
+ { 600, 0.029328, 0.941343, 1.934254 },
+ { 1000, 0.047918, 0.904163, 1.884869 },
+ { 3000, 0.130408, 0.739184, 1.582718 },
+ { 6000, 0.226555, 0.546889, 1.015267 },
+ { 12000, 0.344937, 0.310127, -0.181410 },
+ { 14000, 0.366438, 0.267123, -0.521151 },
+ { 16000, 0.379009, 0.241981, -0.808451 },
+ }
+};
+static const eqz_config_t eqz_config_48000_10b =
+{
+ 10,
+ {
+ { 60, 0.002769, 0.994462, 1.994400 },
+ { 170, 0.007806, 0.984388, 1.983897 },
+ { 310, 0.014143, 0.971714, 1.970091 },
+ { 600, 0.027011, 0.945978, 1.939979 },
+ { 1000, 0.044203, 0.911595, 1.895241 },
+ { 3000, 0.121223, 0.757553, 1.623767 },
+ { 6000, 0.212888, 0.574224, 1.113145 },
+ { 12000, 0.331347, 0.337307, 0.000000 },
+ { 14000, 0.355263, 0.289473, -0.333740 },
+ { 16000, 0.371900, 0.256201, -0.628100 }
+ }
+};
+
+typedef struct
+{
+ char *psz_name;
+ int i_band;
+ float f_amp[];
+} eqz_preset_t;
+
+static const eqz_preset_t eqz_preset_flat_10b=
+{
+ "flat", 10,
+ { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 },
+};
+static const eqz_preset_t eqz_preset_classical_10b=
+{
+ "classical", 10,
+ { -1.11022e-15, -1.11022e-15, -1.11022e-15, -1.11022e-15, -1.11022e-15, -1.11022e-15, -7.2, -7.2, -7.2, -9.6 }
+};
+static const eqz_preset_t eqz_preset_club_10b=
+{
+ "club", 10,
+ { -1.11022e-15, -1.11022e-15, 8, 5.6, 5.6, 5.6, 3.2, -1.11022e-15, -1.11022e-15, -1.11022e-15 }
+};
+static const eqz_preset_t eqz_preset_dance_10b=
+{
+ "dance", 10,
+ { 9.6, 7.2, 2.4, -1.11022e-15, -1.11022e-15, -5.6, -7.2, -7.2, -1.11022e-15, -1.11022e-15 }
+};
+static const eqz_preset_t eqz_preset_fullbass_10b=
+{
+ "fullbass", 10,
+ { -8, 9.6, 9.6, 5.6, 1.6, -4, -8, -10.4, -11.2, -11.2 }
+};
+static const eqz_preset_t eqz_preset_fullbasstreeble_10b=
+{
+ "fullbasstreeble", 10,
+ { 7.2, 5.6, -1.11022e-15, -7.2, -4.8, 1.6, 8, 11.2, 12, 12 }
+};
+
+static const eqz_preset_t eqz_preset_fulltreeble_10b=
+{
+ "fulltreeble", 10,
+ { -9.6, -9.6, -9.6, -4, 2.4, 11.2, 16, 16, 16, 16.8 }
+};
+static const eqz_preset_t eqz_preset_headphones_10b=
+{
+ "headphones", 10,
+ { 4.8, 11.2, 5.6, -3.2, -2.4, 1.6, 4.8, 9.6, 12.8, 14.4 }
+};
+static const eqz_preset_t eqz_preset_largehall_10b=
+{
+ "largehall", 10,
+ { 10.4, 10.4, 5.6, 5.6, -1.11022e-15, -4.8, -4.8, -4.8, -1.11022e-15, -1.11022e-15 }
+};
+static const eqz_preset_t eqz_preset_live_10b=
+{
+ "live", 10,
+ { -4.8, -1.11022e-15, 4, 5.6, 5.6, 5.6, 4, 2.4, 2.4, 2.4 }
+};
+static const eqz_preset_t eqz_preset_party_10b=
+{
+ "party", 10,
+ { 7.2, 7.2, -1.11022e-15, -1.11022e-15, -1.11022e-15, -1.11022e-15, -1.11022e-15, -1.11022e-15, 7.2, 7.2 }
+};
+static const eqz_preset_t eqz_preset_pop_10b=
+{
+ "pop", 10,
+ { -1.6, 4.8, 7.2, 8, 5.6, -1.11022e-15, -2.4, -2.4, -1.6, -1.6 }
+};
+static const eqz_preset_t eqz_preset_reggae_10b=
+{
+ "reggae", 10,
+ { -1.11022e-15, -1.11022e-15, -1.11022e-15, -5.6, -1.11022e-15, 6.4, 6.4, -1.11022e-15, -1.11022e-15, -1.11022e-15 }
+};
+static const eqz_preset_t eqz_preset_rock_10b=
+{
+ "rock", 10,
+ { 8, 4.8, -5.6, -8, -3.2, 4, 8.8, 11.2, 11.2, 11.2 }
+};
+static const eqz_preset_t eqz_preset_ska_10b=
+{
+ "ska", 10,
+ { -2.4, -4.8, -4, -1.11022e-15, 4, 5.6, 8.8, 9.6, 11.2, 9.6 }
+};
+static const eqz_preset_t eqz_preset_soft_10b=
+{
+ "soft", 10,
+ { 4.8, 1.6, -1.11022e-15, -2.4, -1.11022e-15, 4, 8, 9.6, 11.2, 12 }
+};
+static const eqz_preset_t eqz_preset_softrock_10b=
+{
+ "softrock", 10,
+ { 4, 4, 2.4, -1.11022e-15, -4, -5.6, -3.2, -1.11022e-15, 2.4, 8.8 }
+};
+static const eqz_preset_t eqz_preset_techno_10b=
+{
+ "techno", 10,
+ { 8, 5.6, -1.11022e-15, -5.6, -4.8, -1.11022e-15, 8, 9.6, 9.6, 8.8 }
+};
+
+static const eqz_preset_t *eqz_preset_10b[] =
+{
+ &eqz_preset_flat_10b,
+ &eqz_preset_classical_10b,
+ &eqz_preset_club_10b,
+ &eqz_preset_dance_10b,
+ &eqz_preset_fullbass_10b,
+ &eqz_preset_fullbasstreeble_10b,
+ &eqz_preset_fulltreeble_10b,
+ &eqz_preset_headphones_10b,
+ &eqz_preset_largehall_10b,
+ &eqz_preset_live_10b,
+ &eqz_preset_party_10b,
+ &eqz_preset_pop_10b,
+ &eqz_preset_reggae_10b,
+ &eqz_preset_rock_10b,
+ &eqz_preset_ska_10b,
+ &eqz_preset_soft_10b,
+ &eqz_preset_softrock_10b,
+ &eqz_preset_techno_10b,
+ NULL
+};
+
+
+static inline float EqzConvertdB( float db )
+{
+ /* Map it to gain,
+ * (we do as if the input of iir is /EQZ_IN_FACTOR, but in fact it's the non iir data that is *EQZ_IN_FACTOR)
+ * db = 20*log( out / in ) with out = in + amp*iir(i/EQZ_IN_FACTOR)
+ * or iir(i) == i for the center freq so
+ * db = 20*log( 1 + amp/EQZ_IN_FACTOR )
+ * -> amp = EQZ_IN_FACTOR*(10^(db/20) - 1)
+ **/
+
+ if( db < -20.0 )
+ db = -20.0;
+ else if( db > 20.0 )
+ db = 20.0;
+ return EQZ_IN_FACTOR * ( pow( 10, db / 20.0 ) - 1.0 );
+}
+
+static int EqzInit( aout_filter_t *p_filter, int i_rate )
+{
+ aout_filter_sys_t *p_sys = p_filter->p_sys;
+ const eqz_config_t *p_cfg;
+ char *psz;
+ int i, ch;
+ float f_float;
+
+ /* Select the config */
+ if( i_rate == 48000 )
+ {
+ p_cfg = &eqz_config_48000_10b;
+ }
+ else if( i_rate == 44100 )
+ {
+ p_cfg = &eqz_config_44100_10b;
+ }
+ else
+ {
+ /* TODO compute the coeffs on the fly */
+ msg_Err( p_filter, "unsupported rate" );
+ return VLC_EGENERIC;
+ }
+
+ /* Create the static filter config */
+ p_sys->i_band = p_cfg->i_band;
+ p_sys->f_alpha = malloc( p_sys->i_band * sizeof(float) );
+ p_sys->f_beta = malloc( p_sys->i_band * sizeof(float) );
+ p_sys->f_gamma = malloc( p_sys->i_band * sizeof(float) );
+ for( i = 0; i < p_sys->i_band; i++ )
+ {
+ p_sys->f_alpha[i] = p_cfg->band[i].f_alpha;
+ p_sys->f_beta[i] = p_cfg->band[i].f_beta;
+ p_sys->f_gamma[i] = p_cfg->band[i].f_gamma;
+ }
+
+ /* Filter dyn config */
+ p_sys->b_2eqz = VLC_FALSE;
+ p_sys->f_gamp = 1.0;
+ p_sys->f_amp = malloc( p_sys->i_band * sizeof(float) );
+ for( i = 0; i < p_sys->i_band; i++ )
+ {
+ p_sys->f_amp[i] = 0.0;
+ }
+
+ /* Filter state */
+ for( ch = 0; ch < 32; ch++ )
+ {
+ p_sys->x[ch][0] =
+ p_sys->x[ch][1] =
+ p_sys->x2[ch][0] =
+ p_sys->x2[ch][1] = 0.0;
+
+ for( i = 0; i < p_sys->i_band; i++ )
+ {
+ p_sys->y[ch][i][0] =
+ p_sys->y[ch][i][1] =
+ p_sys->y2[ch][i][0] =
+ p_sys->y2[ch][i][1] = 0.0;
+ }
+ }
+
+ /* Now parse config */
+ p_sys->b_2eqz = var_CreateGetBool( p_filter, "equalizer-2pass" );
+ f_float = var_CreateGetFloat( p_filter, "equalizer-preamp" );
+ if( f_float < -20.0 )
+ f_float = -20.0;
+ else if( f_float > 20.0 )
+ f_float = 20.0;
+ p_sys->f_gamp = pow( 10, f_float /20.0);
+
+ psz = var_CreateGetString( p_filter, "equalizer-preset" );
+ if( *psz && p_sys->i_band == 10 )
+ {
+ int i;
+ /* */
+ for( i = 0; eqz_preset_10b[i] != NULL; i++ )
+ {
+ if( !strcasecmp( eqz_preset_10b[i]->psz_name, psz ) )
+ {
+ int j;
+ for( j = 0; j < p_sys->i_band; j++ )
+ p_sys->f_amp[j] = EqzConvertdB( eqz_preset_10b[i]->f_amp[j] );
+ break;
+ }
+ }
+ if( eqz_preset_10b[i] == NULL )
+ {
+ msg_Err( p_filter, "equalizer preset '%s' not found", psz );
+ msg_Dbg( p_filter, "full list:" );
+ for( i = 0; eqz_preset_10b[i] != NULL; i++ )
+ msg_Dbg( p_filter, " - '%s'", eqz_preset_10b[i]->psz_name );
+ }
+ }
+ free( psz );
+
+ psz = var_CreateGetString( p_filter, "equalizer-bands" );
+ if( *psz )
+ {
+ char *p = psz;
+ int i;
+ for( i = 0; i < p_sys->i_band; i++ )
+ {
+ float f;
+
+ /* Read dB -20/20*/
+ f = strtof( p, &p );
+
+ p_sys->f_amp[i] = EqzConvertdB( f );
+
+ if( p == NULL )
+ break;
+ p++;
+ if( *p == '\0' )
+ break;
+ }
+ }
+ free( psz );
+
+ msg_Dbg( p_filter, "equalizer loaded for %d Hz with %d bands %d pass",
+ i_rate, p_sys->i_band, p_sys->b_2eqz ? 2 : 1 );
+ for( i = 0; i < p_sys->i_band; i++ )
+ {
+ msg_Dbg( p_filter, " %d Hz -> factor:%f alpha:%f beta:%f gamma:%f",
+ (int)p_cfg->band[i].f_frequency, p_sys->f_amp[i],
+ p_sys->f_alpha[i], p_sys->f_beta[i], p_sys->f_gamma[i]);
+ }
+ return VLC_SUCCESS;
+}
+
+static void EqzFilter( aout_filter_t *p_filter, float *out, float *in, int i_samples, int i_channels )
+{
+ aout_filter_sys_t *p_sys = p_filter->p_sys;
+ int i, ch, j;
+
+ for( i = 0; i < i_samples; i++ )
+ {
+ for( ch = 0; ch < i_channels; ch++ )
+ {
+ const float x = in[ch];
+ float o = 0.0;
+
+ for( j = 0; j < p_sys->i_band; j++ )
+ {
+ float y = p_sys->f_alpha[j] * ( x - p_sys->x[ch][1] ) +
+ p_sys->f_gamma[j] * p_sys->y[ch][j][0] -
+ p_sys->f_beta[j] * p_sys->y[ch][j][1];
+
+ p_sys->y[ch][j][1] = p_sys->y[ch][j][0];
+ p_sys->y[ch][j][0] = y;
+
+ o += y * p_sys->f_amp[j];
+ }
+ p_sys->x[ch][1] = p_sys->x[ch][0];
+ p_sys->x[ch][0] = x;
+
+ /* Second filter */
+ if( p_sys->b_2eqz )
+ {
+ const float x2 = EQZ_IN_FACTOR * x + o;
+ o = 0.0;
+ for( j = 0; j < p_sys->i_band; j++ )
+ {
+ float y = p_sys->f_alpha[j] * ( x2 - p_sys->x2[ch][1] ) +
+ p_sys->f_gamma[j] * p_sys->y2[ch][j][0] -
+ p_sys->f_beta[j] * p_sys->y2[ch][j][1];
+
+ p_sys->y2[ch][j][1] = p_sys->y2[ch][j][0];
+ p_sys->y2[ch][j][0] = y;
+
+ o += y * p_sys->f_amp[j];
+ }
+ p_sys->x2[ch][1] = p_sys->x2[ch][0];
+ p_sys->x2[ch][0] = x2;
+
+ /* We add source PCM + filtered PCM */
+ out[ch] = p_sys->f_gamp *( EQZ_IN_FACTOR * x2 + o );
+ }
+ else
+ {
+ /* We add source PCM + filtered PCM */
+ out[ch] = p_sys->f_gamp *( EQZ_IN_FACTOR * x + o );
+ }
+ }
+
+ in += i_channels;
+ out += i_channels;
+ }
+}
+
+static void EqzClean( aout_filter_t *p_filter )
+{
+ aout_filter_sys_t *p_sys = p_filter->p_sys;
+
+ free( p_sys->f_alpha );
+ free( p_sys->f_beta );
+ free( p_sys->f_gamma );
+
+ free( p_sys->f_amp );
+}
+