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     int             time_window;
 101     float           alarm_threshold;
 102     int             repetition_time;
 103     int             counter;
 104     int             nbChannels;
 105     ValueDate_t*    first;
 106     ValueDate_t*    last;
 107     int             started;
 108     mtime_t         lastAlarm;
 109 };
 110
 111 /*****************************************************************************
 112  * Open: open the visualizer
 113  *****************************************************************************/
 114 static int Open( vlc_object_t *p_this )
 115 {
 116     filter_t     *p_filter = (filter_t *)p_this;
 117     filter_sys_t *p_sys = p_filter->p_sys = malloc( sizeof( *p_sys ) );
 118     if( !p_sys )
 119         return VLC_ENOMEM;
 120
 121     p_sys->bargraph = var_CreateGetIntegerCommand( p_filter, "audiobargraph_a-bargraph" );
 122     p_sys->bargraph_repetition = var_CreateGetIntegerCommand( p_filter, "audiobargraph_a-bargraph_repetition" );
 123     p_sys->silence = var_CreateGetIntegerCommand( p_filter, "audiobargraph_a-silence" );
 124     p_sys->time_window = var_CreateGetIntegerCommand( p_filter, "audiobargraph_a-time_window" );
 125     p_sys->alarm_threshold = var_CreateGetFloatCommand( p_filter, "audiobargraph_a-alarm_threshold" );
 126     p_sys->repetition_time = var_CreateGetIntegerCommand( p_filter, "audiobargraph_a-repetition_time" );
 127     p_sys->counter = 0;
 128     p_sys->nbChannels = 0;
 129     p_sys->first = NULL;
 130     p_sys->last = NULL;
 131     p_sys->started = 0;
 132     p_sys->lastAlarm = 0;
 133
 134     p_filter->fmt_in.audio.i_format = VLC_CODEC_FL32;
 135     p_filter->fmt_out.audio = p_filter->fmt_in.audio;
 136     p_filter->pf_audio_filter = DoWork;
 137
 138     var_Create( p_filter->p_libvlc, "audiobargraph_v-alarm", VLC_VAR_BOOL );
 139     var_Create( p_filter->p_libvlc, "audiobargraph_v-i_values", VLC_VAR_STRING );
 140
 141     return VLC_SUCCESS;
 142 }
 143
 144 /*****************************************************************************
 145  * DoWork: treat an audio buffer
 146  ****************************************************************************/
 147 static block_t *DoWork( filter_t *p_filter, block_t *p_in_buf )
 148 {
 149     filter_sys_t *p_sys = p_filter->p_sys;
 150     int i;
 151     float *p_sample = (float *)p_in_buf->p_buffer;
 152     float i_value[AOUT_CHAN_MAX];
 153     float ch;
 154     float max = 0.0;
 155     int nbChannels = 0;
 156     ValueDate_t* current = NULL;
 157     float sum;
 158     int count = 0;
 159
 160     nbChannels = aout_FormatNbChannels( &p_filter->fmt_in.audio );
 161     p_sys->nbChannels = nbChannels;
 162
 163     for (i=0; i<nbChannels; i++) {
 164         i_value[i] = 0.;
 165     }
 166
 167     /* 1 - Compute the peack values */
 168     for ( i = 0 ; i < (int)(p_in_buf->i_nb_samples); i++ )
 169     {
 170         for (int j = 0; j<nbChannels; j++) {
 171             ch = (*p_sample++);
 172             if (ch > i_value[j])
 173                 i_value[j] = ch;
 174             if (ch > max)
 175                 max = ch;
 176         }
 177     }
 178     max = powf( max, 2 );
 179
 180     if (p_sys->silence) {
 181         /* 2 - store the new value */
 182         ValueDate_t *new = xmalloc(sizeof(*new));
 183         new->value = max;
 184         new->date = p_in_buf->i_pts;
 185         new->next = NULL;
 186         if (p_sys->last != NULL) {
 187             p_sys->last->next = new;
 188         }
 189         p_sys->last = new;
 190         if (p_sys->first == NULL) {
 191             p_sys->first = new;
 192         }
 193
 194         /* 3 - delete too old values */
 195         while (p_sys->first->date < (new->date - (p_sys->time_window*1000))) {
 196             p_sys->started = 1; // we have enough values to compute a valid total
 197             current = p_sys->first;
 198             p_sys->first = p_sys->first->next;
 199             free(current);
 200         }
 201
 202         /* If last message was sent enough time ago */
 203         if ((p_sys->started) && (p_in_buf->i_pts > p_sys->lastAlarm + (p_sys->repetition_time*1000))) {
 204
 205             /* 4 - compute the RMS */
 206             current = p_sys->first;
 207             sum = 0.0;
 208             while (current != NULL) {
 209                 sum += current->value;
 210                 count ++;
 211                 current = current->next;
 212             }
 213             sum /= count;
 214             sum = sqrtf(sum);
 215
 216             /* 5 - compare it to the threshold */
 217             var_SetBool(p_filter->p_libvlc, "audiobargraph_v-alarm",
 218                         sum < p_sys->alarm_threshold);
 219
 220             p_sys->lastAlarm = p_in_buf->i_pts;
 221         }
 222     }
 223
 224     /*for (i=0; i<nbChannels; i++) {
 225         value[i] = abs(i_value[i]*100);
 226         if ( value[i] > p_sys->value[i] - 6 )
 227             p_sys->value[i] = value[i];
 228         else
 229             p_sys->value[i] = p_sys->value[i] - 6;
 230     }*/
 231
 232     if (p_sys->bargraph) {
 233         /* 6 - sent the message with the values for the BarGraph */
 234         if ((nbChannels > 0) && (p_sys->counter%(p_sys->bargraph_repetition) == 0)) {
 235             char message[256];
 236             size_t j = 0;
 237
 238             for (i = 0; i < nbChannels; i++) {
 239                 if (j >= sizeof (message))
 240                     break;
 241                 j += snprintf(message + j, sizeof (message),"%f:", i_value[i]);
 242             }
 243
 244             message[--j] = '\0';
 245             msg_Dbg( p_filter, "values: %s", message );
 246
 247             var_SetString(p_filter->p_libvlc, "audiobargraph_v-i_values",
 248                           message);
 249         }
 250     }
 251
 252     if (p_sys->counter > p_sys->bargraph_repetition*100)
 253         p_sys->counter = 0;
 254
 255     p_sys->counter++;
 256
 257     return p_in_buf;
 258 }
 259
 260 /*****************************************************************************
 261  * Close: close the plugin
 262  *****************************************************************************/
 263 static void Close( vlc_object_t *p_this )
 264 {
 265     filter_t * p_filter = (filter_t *)p_this;
 266     filter_sys_t *p_sys = p_filter->p_sys;
 267
 268     var_Destroy( p_filter->p_libvlc, "audiobargraph_v-i_values" );
 269     var_Destroy( p_filter->p_libvlc, "audiobargraph_v-alarm" );
 270
 271     while (p_sys->first != NULL) {
 272         ValueDate_t *current = p_sys->first;
 273         p_sys->first = p_sys->first->next;
 274         free(current);
 275     }
 276     free( p_sys );
 277 }