libaf/af_pan.c

   1 /*=============================================================================
   2 //
   3 //  This software has been released under the terms of the GNU General Public
   4 //  license. See http://www.gnu.org/copyleft/gpl.html for details.
   5 //
   6 //  Copyright 2002 Anders Johansson ajh@atri.curtin.edu.au
   7 //
   8 //=============================================================================
   9 */
  10
  11 /* */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15
  16 #include <unistd.h>
  17 #include <inttypes.h>
  18 #include <math.h>
  19 #include <limits.h>
  20
  21 #include "af.h"
  22
  23 // Data for specific instances of this filter
  24 typedef struct af_pan_s
  25 {
  26   float level[AF_NCH][AF_NCH];  // Gain level for each channel
  27 }af_pan_t;
  28
  29 // Initialization and runtime control
  30 static int control(struct af_instance_s* af, int cmd, void* arg)
  31 {
  32   af_pan_t* s = af->setup;
  33
  34   switch(cmd){
  35   case AF_CONTROL_REINIT:
  36     // Sanity check
  37     if(!arg) return AF_ERROR;
  38
  39     af->data->rate   = ((af_data_t*)arg)->rate;
  40     af->data->format = AF_FORMAT_FLOAT_NE;
  41     af->data->bps    = 4;
  42     af->mul.n        = af->data->nch;
  43     af->mul.d        = ((af_data_t*)arg)->nch;
  44     af_frac_cancel(&af->mul);
  45
  46     if((af->data->format != ((af_data_t*)arg)->format) ||
  47        (af->data->bps != ((af_data_t*)arg)->bps)){
  48       ((af_data_t*)arg)->format = af->data->format;
  49       ((af_data_t*)arg)->bps = af->data->bps;
  50       return AF_FALSE;
  51     }
  52     return control(af,AF_CONTROL_PAN_NOUT | AF_CONTROL_SET, &af->data->nch);
  53   case AF_CONTROL_COMMAND_LINE:{
  54     int   nch = 0;
  55     int   n = 0;
  56     char* cp = NULL;
  57     int   j,k;
  58     // Read number of outputs
  59     sscanf((char*)arg,"%i%n", &nch,&n);
  60     if(AF_OK != control(af,AF_CONTROL_PAN_NOUT | AF_CONTROL_SET, &nch))
  61       return AF_ERROR;
  62
  63     // Read pan values
  64     cp = &((char*)arg)[n];
  65     j = 0; k = 0;
  66     while((*cp == ':') && (k < AF_NCH)){
  67       sscanf(cp, ":%f%n" , &s->level[j][k], &n);
  68       af_msg(AF_MSG_VERBOSE,"[pan] Pan level from channel %i to"
  69              " channel %i = %f\n",k,j,s->level[j][k]);
  70       cp =&cp[n];
  71       j++;
  72       if(j>=nch){
  73         j = 0;
  74         k++;
  75       }
  76     }
  77     return AF_OK;
  78   }
  79   case AF_CONTROL_PAN_LEVEL | AF_CONTROL_SET:{
  80     int    i;
  81     int    ch = ((af_control_ext_t*)arg)->ch;
  82     float* level = ((af_control_ext_t*)arg)->arg;
  83     if (ch >= AF_NCH)
  84       return AF_FALSE;
  85     for(i=0;i<AF_NCH;i++)
  86       s->level[ch][i] = level[i];
  87     return AF_OK;
  88   }
  89   case AF_CONTROL_PAN_LEVEL | AF_CONTROL_GET:{
  90     int    i;
  91     int ch = ((af_control_ext_t*)arg)->ch;
  92     float* level = ((af_control_ext_t*)arg)->arg;
  93     if (ch >= AF_NCH)
  94       return AF_FALSE;
  95     for(i=0;i<AF_NCH;i++)
  96       level[i] = s->level[ch][i];
  97     return AF_OK;
  98   }
  99   case AF_CONTROL_PAN_NOUT | AF_CONTROL_SET:
 100     // Reinit must be called after this function has been called
 101
 102     // Sanity check
 103     if(((int*)arg)[0] <= 0 || ((int*)arg)[0] > AF_NCH){
 104       af_msg(AF_MSG_ERROR,"[pan] The number of output channels must be"
 105              " between 1 and %i. Current value is %i\n",AF_NCH,((int*)arg)[0]);
 106       return AF_ERROR;
 107     }
 108     af->data->nch=((int*)arg)[0];
 109     return AF_OK;
 110   case AF_CONTROL_PAN_NOUT | AF_CONTROL_GET:
 111     *(int*)arg = af->data->nch;
 112     return AF_OK;
 113   }
 114   return AF_UNKNOWN;
 115 }
 116
 117 // Deallocate memory
 118 static void uninit(struct af_instance_s* af)
 119 {
 120   if(af->data->audio)
 121     free(af->data->audio);
 122   if(af->data)
 123     free(af->data);
 124   if(af->setup)
 125     free(af->setup);
 126 }
 127
 128 // Filter data through filter
 129 static af_data_t* play(struct af_instance_s* af, af_data_t* data)
 130 {
 131   af_data_t*    c    = data;            // Current working data
 132   af_data_t*    l    = af->data;        // Local data
 133   af_pan_t*     s    = af->setup;       // Setup for this instance
 134   float*        in   = c->audio;        // Input audio data
 135   float*        out  = NULL;            // Output audio data
 136   float*        end  = in+c->len/4;     // End of loop
 137   int           nchi = c->nch;          // Number of input channels
 138   int           ncho = l->nch;          // Number of output channels
 139   register int  j,k;
 140
 141   if(AF_OK != RESIZE_LOCAL_BUFFER(af,data))
 142     return NULL;
 143
 144   out = l->audio;
 145   // Execute panning
 146   // FIXME: Too slow
 147   while(in < end){
 148     for(j=0;j<ncho;j++){
 149       register float  x   = 0.0;
 150       register float* tin = in;
 151       for(k=0;k<nchi;k++)
 152         x += tin[k] * s->level[j][k];
 153       out[j] = x;
 154     }
 155     out+= ncho;
 156     in+= nchi;
 157   }
 158
 159   // Set output data
 160   c->audio = l->audio;
 161   c->len   = (c->len*af->mul.n)/af->mul.d;
 162   c->nch   = l->nch;
 163
 164   return c;
 165 }
 166
 167 // Allocate memory and set function pointers
 168 static int open(af_instance_t* af){
 169   af->control=control;
 170   af->uninit=uninit;
 171   af->play=play;
 172   af->mul.n=1;
 173   af->mul.d=1;
 174   af->data=calloc(1,sizeof(af_data_t));
 175   af->setup=calloc(1,sizeof(af_pan_t));
 176   if(af->data == NULL || af->setup == NULL)
 177     return AF_ERROR;
 178   // Set initial pan to pass-through.
 179   return AF_OK;
 180 }
 181
 182 // Description of this filter
 183 af_info_t af_info_pan = {
 184     "Panning audio filter",
 185     "pan",
 186     "Anders",
 187     "",
 188     AF_FLAGS_NOT_REENTRANT,
 189     open
 190 };