modules/audio_filter/audiobargraph_a.c

   1 /*****************************************************************************
   2  * audiobargraph_a.c : audiobargraph audio plugin for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2002-2009 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Clement CHESNIN <clement.chesnin@gmail.com>
   8  *          Philippe COENT <philippe.coent@tdf.fr>
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_aout.h>
  35 #include <vlc_filter.h>
  36
  37 #include <math.h>
  38
  39 #define BARGRAPH_TEXT N_("Defines if BarGraph information should be sent")
  40 #define BARGRAPH_LONGTEXT N_("Defines if BarGraph information should be sent. "\
  41                 "1 if the information should be sent, 0 otherwise (default 1)." )
  42 #define BARGRAPH_REPETITION_TEXT N_("Sends the barGraph information every n audio packets")
  43 #define BARGRAPH_REPETITION_LONGTEXT N_("Defines how often the barGraph information should be sent. "\
  44                 "Sends the barGraph information every n audio packets (default 4)." )
  45 #define SILENCE_TEXT N_("Defines if silence alarm information should be sent")
  46 #define SILENCE_LONGTEXT N_("Defines if silence alarm information should be sent. "\
  47                 "1 if the information should be sent, 0 otherwise (default 1)." )
  48 #define TIME_WINDOW_TEXT N_("Time window to use in ms")
  49 #define TIME_WINDOW_LONGTEXT N_("Time Window during when the audio level is measured in ms for silence detection. "\
  50                 "If the audio level is under the threshold during this time, "\
  51                 "an alarm is sent (default 5000)." )
  52 #define ALARM_THRESHOLD_TEXT N_("Minimum Audio level to raise the alarm")
  53 #define ALARM_THRESHOLD_LONGTEXT N_("Threshold to be attained to raise an alarm. "\
  54                 "If the audio level is under the threshold during this time, "\
  55                 "an alarm is sent (default 0.1)." )
  56 #define REPETITION_TIME_TEXT N_("Time between two alarm messages in ms" )
  57 #define REPETITION_TIME_LONGTEXT N_("Time between two alarm messages in ms. "\
  58                 "This value is used to avoid alarm saturation (default 2000)." )
  59
  60 #define CFG_PREFIX "audiobargraph_a-"
  61
  62 /*****************************************************************************
  63  * Module descriptor
  64  *****************************************************************************/
  65 static int  Open( vlc_object_t * );
  66 static void Close( vlc_object_t * );
  67 static block_t *DoWork( filter_t *, block_t * );
  68
  69 vlc_module_begin ()
  70     set_description( N_("Audio part of the BarGraph function") )
  71     set_shortname( N_("Audiobar Graph") )
  72     set_capability( "audio filter", 0 )
  73     set_category( CAT_AUDIO )
  74     set_subcategory( SUBCAT_AUDIO_AFILTER )
  75
  76     add_obsolete_string( CFG_PREFIX "address" )
  77     add_obsolete_integer( CFG_PREFIX "port" )
  78     add_integer( CFG_PREFIX "bargraph", 1, BARGRAPH_TEXT, BARGRAPH_LONGTEXT, false )
  79     add_integer( CFG_PREFIX "bargraph_repetition", 4, BARGRAPH_REPETITION_TEXT, BARGRAPH_REPETITION_LONGTEXT, false )
  80     add_integer( CFG_PREFIX "silence", 1, SILENCE_TEXT, SILENCE_LONGTEXT, false )
  81     add_integer( CFG_PREFIX "time_window", 5000, TIME_WINDOW_TEXT, TIME_WINDOW_LONGTEXT, false )
  82     add_float( CFG_PREFIX "alarm_threshold", 0.1, ALARM_THRESHOLD_TEXT, ALARM_THRESHOLD_LONGTEXT, false )
  83     add_integer( CFG_PREFIX "repetition_time", 2000, REPETITION_TIME_TEXT, REPETITION_TIME_LONGTEXT, false )
  84     add_obsolete_integer( CFG_PREFIX "connection_reset" )
  85
  86     set_callbacks( Open, Close )
  87 vlc_module_end ()
  88
  89 typedef struct ValueDate_t {
  90     float value;
  91     mtime_t date;
  92     struct ValueDate_t* next;
  93 } ValueDate_t;
  94
  95 struct filter_sys_t
  96 {
  97     int             bargraph;
  98     int             bargraph_repetition;
  99     int             silence;
 100     int64_t         time_window;
 101     float           alarm_threshold;
 102     int64_t         repetition_time;
 103     int             counter;
 104     ValueDate_t*    first;
 105     ValueDate_t*    last;
 106     int             started;
 107     mtime_t         lastAlarm;
 108 };
 109
 110 /*****************************************************************************
 111  * Open: open the visualizer
 112  *****************************************************************************/
 113 static int Open( vlc_object_t *p_this )
 114 {
 115     filter_t     *p_filter = (filter_t *)p_this;
 116     filter_sys_t *p_sys = p_filter->p_sys = malloc( sizeof( *p_sys ) );
 117     if( !p_sys )
 118         return VLC_ENOMEM;
 119
 120     p_sys->bargraph = var_CreateGetInteger( p_filter, CFG_PREFIX "bargraph" );
 121     p_sys->bargraph_repetition = var_CreateGetInteger( p_filter, CFG_PREFIX "bargraph_repetition" );
 122     p_sys->silence = var_CreateGetInteger( p_filter, CFG_PREFIX "silence" );
 123     p_sys->time_window = var_CreateGetInteger( p_filter, CFG_PREFIX "time_window" ) * 1000;
 124     p_sys->alarm_threshold = var_CreateGetFloat( p_filter, CFG_PREFIX "alarm_threshold" );
 125     p_sys->repetition_time = var_CreateGetInteger( p_filter, CFG_PREFIX "repetition_time" ) * 1000;
 126     p_sys->counter = 0;
 127     p_sys->first = NULL;
 128     p_sys->last = NULL;
 129     p_sys->started = 0;
 130     p_sys->lastAlarm = 0;
 131
 132     p_filter->fmt_in.audio.i_format = VLC_CODEC_FL32;
 133     p_filter->fmt_out.audio = p_filter->fmt_in.audio;
 134     p_filter->pf_audio_filter = DoWork;
 135
 136     var_Create( p_filter->p_libvlc, "audiobargraph_v-alarm", VLC_VAR_BOOL );
 137     var_Create( p_filter->p_libvlc, "audiobargraph_v-i_values", VLC_VAR_STRING );
 138
 139     return VLC_SUCCESS;
 140 }
 141
 142 /*****************************************************************************
 143  * DoWork: treat an audio buffer
 144  ****************************************************************************/
 145 static block_t *DoWork( filter_t *p_filter, block_t *p_in_buf )
 146 {
 147     filter_sys_t *p_sys = p_filter->p_sys;
 148     int i;
 149     float *p_sample = (float *)p_in_buf->p_buffer;
 150     float i_value[AOUT_CHAN_MAX];
 151     float ch;
 152     float max = 0.0;
 153     ValueDate_t* current = NULL;
 154     float sum;
 155     int count = 0;
 156
 157     int nbChannels = aout_FormatNbChannels( &p_filter->fmt_in.audio );
 158
 159     for (i=0; i<nbChannels; i++) {
 160         i_value[i] = 0.;
 161     }
 162
 163     /* 1 - Compute the peak values */
 164     for ( i = 0 ; i < (int)(p_in_buf->i_nb_samples); i++ )
 165     {
 166         for (int j = 0; j<nbChannels; j++) {
 167             ch = (*p_sample++);
 168             if (ch > i_value[j])
 169                 i_value[j] = ch;
 170             if (ch > max)
 171                 max = ch;
 172         }
 173     }
 174     max = powf( max, 2 );
 175
 176     if (p_sys->silence) {
 177         /* 2 - store the new value */
 178         ValueDate_t *new = xmalloc(sizeof(*new));
 179         new->value = max;
 180         new->date = p_in_buf->i_pts;
 181         new->next = NULL;
 182         if (p_sys->last != NULL) {
 183             p_sys->last->next = new;
 184         }
 185         p_sys->last = new;
 186         if (p_sys->first == NULL) {
 187             p_sys->first = new;
 188         }
 189
 190         /* 3 - delete too old values */
 191         while (p_sys->first->date < (new->date - p_sys->time_window)) {
 192             p_sys->started = 1; // we have enough values to compute a valid total
 193             current = p_sys->first;
 194             p_sys->first = p_sys->first->next;
 195             free(current);
 196         }
 197
 198         /* If last message was sent enough time ago */
 199         if ((p_sys->started) && (p_in_buf->i_pts > p_sys->lastAlarm + p_sys->repetition_time)) {
 200
 201             /* 4 - compute the RMS */
 202             current = p_sys->first;
 203             sum = 0.0;
 204             while (current != NULL) {
 205                 sum += current->value;
 206                 count ++;
 207                 current = current->next;
 208             }
 209             sum /= count;
 210             sum = sqrtf(sum);
 211
 212             /* 5 - compare it to the threshold */
 213             var_SetBool(p_filter->p_libvlc, "audiobargraph_v-alarm",
 214                         sum < p_sys->alarm_threshold);
 215
 216             p_sys->lastAlarm = p_in_buf->i_pts;
 217         }
 218     }
 219
 220     /*for (i=0; i<nbChannels; i++) {
 221         value[i] = abs(i_value[i]*100);
 222         if ( value[i] > p_sys->value[i] - 6 )
 223             p_sys->value[i] = value[i];
 224         else
 225             p_sys->value[i] = p_sys->value[i] - 6;
 226     }*/
 227
 228     if (p_sys->bargraph) {
 229         /* 6 - sent the message with the values for the BarGraph */
 230         if ((nbChannels > 0) && (p_sys->counter%(p_sys->bargraph_repetition) == 0)) {
 231             char message[256];
 232             size_t j = 0;
 233
 234             for (i = 0; i < nbChannels; i++) {
 235                 if (j >= sizeof (message))
 236                     break;
 237                 j += snprintf(message + j, sizeof (message),"%f:", i_value[i]);
 238             }
 239
 240             message[--j] = '\0';
 241             msg_Dbg( p_filter, "values: %s", message );
 242
 243             var_SetString(p_filter->p_libvlc, "audiobargraph_v-i_values",
 244                           message);
 245         }
 246     }
 247
 248     if (++p_sys->counter > p_sys->bargraph_repetition*100)
 249         p_sys->counter = 0;
 250
 251     return p_in_buf;
 252 }
 253
 254 /*****************************************************************************
 255  * Close: close the plugin
 256  *****************************************************************************/
 257 static void Close( vlc_object_t *p_this )
 258 {
 259     filter_t * p_filter = (filter_t *)p_this;
 260     filter_sys_t *p_sys = p_filter->p_sys;
 261
 262     var_Destroy( p_filter->p_libvlc, "audiobargraph_v-i_values" );
 263     var_Destroy( p_filter->p_libvlc, "audiobargraph_v-alarm" );
 264
 265     while (p_sys->first != NULL) {
 266         ValueDate_t *current = p_sys->first;
 267         p_sys->first = p_sys->first->next;
 268         free(current);
 269     }
 270     free( p_sys );
 271 }