libaf/af_pan.c

   1 /*
   2  * Copyright (C) 2002 Anders Johansson ajh@atri.curtin.edu.au
   3  *
   4  * This file is part of MPlayer.
   5  *
   6  * MPlayer is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * MPlayer is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23
  24 #include <inttypes.h>
  25 #include <math.h>
  26 #include <limits.h>
  27
  28 #include "af.h"
  29
  30 // Data for specific instances of this filter
  31 typedef struct af_pan_s
  32 {
  33   int nch; // Number of output channels; zero means same as input
  34   float level[AF_NCH][AF_NCH];  // Gain level for each channel
  35 }af_pan_t;
  36
  37 // Initialization and runtime control
  38 static int control(struct af_instance_s* af, int cmd, void* arg)
  39 {
  40   af_pan_t* s = af->setup;
  41
  42   switch(cmd){
  43   case AF_CONTROL_REINIT:
  44     // Sanity check
  45     if(!arg) return AF_ERROR;
  46
  47     af->data->rate   = ((af_data_t*)arg)->rate;
  48     af->data->format = AF_FORMAT_FLOAT_NE;
  49     af->data->bps    = 4;
  50     af->data->nch    = s->nch ? s->nch: ((af_data_t*)arg)->nch;
  51     af->mul          = (double)af->data->nch / ((af_data_t*)arg)->nch;
  52
  53     if((af->data->format != ((af_data_t*)arg)->format) ||
  54        (af->data->bps != ((af_data_t*)arg)->bps)){
  55       ((af_data_t*)arg)->format = af->data->format;
  56       ((af_data_t*)arg)->bps = af->data->bps;
  57       return AF_FALSE;
  58     }
  59     return AF_OK;
  60   case AF_CONTROL_COMMAND_LINE:{
  61     int   nch = 0;
  62     int   n = 0;
  63     char* cp = NULL;
  64     int   j,k;
  65     // Read number of outputs
  66     sscanf((char*)arg,"%i%n", &nch,&n);
  67     if(AF_OK != control(af,AF_CONTROL_PAN_NOUT | AF_CONTROL_SET, &nch))
  68       return AF_ERROR;
  69
  70     // Read pan values
  71     cp = &((char*)arg)[n];
  72     j = 0; k = 0;
  73     while((*cp == ':') && (k < AF_NCH)){
  74       sscanf(cp, ":%f%n" , &s->level[j][k], &n);
  75       mp_msg(MSGT_AFILTER, MSGL_V, "[pan] Pan level from channel %i to"
  76              " channel %i = %f\n",k,j,s->level[j][k]);
  77       cp =&cp[n];
  78       j++;
  79       if(j>=nch){
  80         j = 0;
  81         k++;
  82       }
  83     }
  84     return AF_OK;
  85   }
  86   case AF_CONTROL_PAN_LEVEL | AF_CONTROL_SET:{
  87     int    i;
  88     int    ch = ((af_control_ext_t*)arg)->ch;
  89     float* level = ((af_control_ext_t*)arg)->arg;
  90     if (ch >= AF_NCH)
  91       return AF_FALSE;
  92     for(i=0;i<AF_NCH;i++)
  93       s->level[ch][i] = level[i];
  94     return AF_OK;
  95   }
  96   case AF_CONTROL_PAN_LEVEL | AF_CONTROL_GET:{
  97     int    i;
  98     int ch = ((af_control_ext_t*)arg)->ch;
  99     float* level = ((af_control_ext_t*)arg)->arg;
 100     if (ch >= AF_NCH)
 101       return AF_FALSE;
 102     for(i=0;i<AF_NCH;i++)
 103       level[i] = s->level[ch][i];
 104     return AF_OK;
 105   }
 106   case AF_CONTROL_PAN_NOUT | AF_CONTROL_SET:
 107     // Reinit must be called after this function has been called
 108
 109     // Sanity check
 110     if(((int*)arg)[0] <= 0 || ((int*)arg)[0] > AF_NCH){
 111       mp_msg(MSGT_AFILTER, MSGL_ERR, "[pan] The number of output channels must be"
 112              " between 1 and %i. Current value is %i\n",AF_NCH,((int*)arg)[0]);
 113       return AF_ERROR;
 114     }
 115     s->nch=((int*)arg)[0];
 116     return AF_OK;
 117   case AF_CONTROL_PAN_NOUT | AF_CONTROL_GET:
 118     *(int*)arg = af->data->nch;
 119     return AF_OK;
 120   case AF_CONTROL_PAN_BALANCE | AF_CONTROL_SET:{
 121     float val = *(float*)arg;
 122     if (s->nch)
 123       return AF_ERROR;
 124     if (af->data->nch >= 2) {
 125       s->level[0][0] = min(1.f, 1.f - val);
 126       s->level[0][1] = max(0.f, val);
 127       s->level[1][0] = max(0.f, -val);
 128       s->level[1][1] = min(1.f, 1.f + val);
 129     }
 130     return AF_OK;
 131   }
 132   case AF_CONTROL_PAN_BALANCE | AF_CONTROL_GET:
 133     if (s->nch)
 134       return AF_ERROR;
 135     *(float*)arg = s->level[0][1] - s->level[1][0];
 136     return AF_OK;
 137   }
 138   return AF_UNKNOWN;
 139 }
 140
 141 // Deallocate memory
 142 static void uninit(struct af_instance_s* af)
 143 {
 144   if(af->data)
 145     free(af->data->audio);
 146   free(af->data);
 147   free(af->setup);
 148 }
 149
 150 // Filter data through filter
 151 static af_data_t* play(struct af_instance_s* af, af_data_t* data)
 152 {
 153   af_data_t*    c    = data;            // Current working data
 154   af_data_t*    l    = af->data;        // Local data
 155   af_pan_t*     s    = af->setup;       // Setup for this instance
 156   float*        in   = c->audio;        // Input audio data
 157   float*        out  = NULL;            // Output audio data
 158   float*        end  = in+c->len/4;     // End of loop
 159   int           nchi = c->nch;          // Number of input channels
 160   int           ncho = l->nch;          // Number of output channels
 161   register int  j,k;
 162
 163   if(AF_OK != RESIZE_LOCAL_BUFFER(af,data))
 164     return NULL;
 165
 166   out = l->audio;
 167   // Execute panning
 168   // FIXME: Too slow
 169   while(in < end){
 170     for(j=0;j<ncho;j++){
 171       register float  x   = 0.0;
 172       register float* tin = in;
 173       for(k=0;k<nchi;k++)
 174         x += tin[k] * s->level[j][k];
 175       out[j] = x;
 176     }
 177     out+= ncho;
 178     in+= nchi;
 179   }
 180
 181   // Set output data
 182   c->audio = l->audio;
 183   c->len   = c->len / c->nch * l->nch;
 184   c->nch   = l->nch;
 185
 186   return c;
 187 }
 188
 189 // Allocate memory and set function pointers
 190 static int af_open(af_instance_t* af){
 191   af->control=control;
 192   af->uninit=uninit;
 193   af->play=play;
 194   af->mul=1;
 195   af->data=calloc(1,sizeof(af_data_t));
 196   af->setup=calloc(1,sizeof(af_pan_t));
 197   if(af->data == NULL || af->setup == NULL)
 198     return AF_ERROR;
 199   return AF_OK;
 200 }
 201
 202 // Description of this filter
 203 af_info_t af_info_pan = {
 204     "Panning audio filter",
 205     "pan",
 206     "Anders",
 207     "",
 208     AF_FLAGS_REENTRANT,
 209     af_open
 210 };