libmpcodecs/ad_msgsm.c

   1 /*
   2  * This file is part of MPlayer.
   3  *
   4  * MPlayer is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * MPlayer is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22
  23 #include "config.h"
  24 #include "ad_internal.h"
  25
  26 static const ad_info_t info =
  27 {
  28         "native GSM/MSGSM audio decoder",
  29         "msgsm",
  30         "A'rpi",
  31         "XAnim",
  32         ""
  33 };
  34
  35 LIBAD_EXTERN(msgsm)
  36
  37 #include "native/xa_gsm.h"
  38
  39 static int init(sh_audio_t *sh_audio)
  40 {
  41   if(!sh_audio->wf) return 0;
  42   // MS-GSM audio codec:
  43   GSM_Init();
  44   sh_audio->channels=sh_audio->wf->nChannels;
  45   sh_audio->samplerate=sh_audio->wf->nSamplesPerSec;
  46   sh_audio->samplesize=2;
  47   // decodes 65 byte -> 320 short
  48   // 1 sec: sh_audio->channels*sh_audio->samplerate  samples
  49   // 1 frame: 320 samples
  50   if(sh_audio->format==0x31 || sh_audio->format==0x32){
  51     sh_audio->ds->ss_mul=65; sh_audio->ds->ss_div=320;
  52   } else {
  53     sh_audio->ds->ss_mul=33; sh_audio->ds->ss_div=160;
  54   }
  55   sh_audio->i_bps=sh_audio->ds->ss_mul*(sh_audio->channels*sh_audio->samplerate)/sh_audio->ds->ss_div;  // 1:10
  56   return 1;
  57 }
  58
  59 static int preinit(sh_audio_t *sh_audio)
  60 {
  61   sh_audio->audio_out_minsize=4*320;
  62   return 1;
  63 }
  64
  65 static void uninit(sh_audio_t *sh)
  66 {
  67 }
  68
  69 static int control(sh_audio_t *sh,int cmd,void* arg, ...)
  70 {
  71   return CONTROL_UNKNOWN;
  72 }
  73
  74 static int decode_audio(sh_audio_t *sh_audio,unsigned char *buf,int minlen,int maxlen)
  75 {
  76   if(sh_audio->format==0x31 || sh_audio->format==0x32){
  77     unsigned char ibuf[65]; // 65 bytes / frame
  78     if(demux_read_data(sh_audio->ds,ibuf,65)!=65) return -1; // EOF
  79     XA_MSGSM_Decoder(ibuf,(unsigned short *) buf); // decodes 65 byte -> 320 short
  80     return 2*320;
  81   } else {
  82     unsigned char ibuf[33]; // 33 bytes / frame
  83     if(demux_read_data(sh_audio->ds,ibuf,33)!=33) return -1; // EOF
  84     XA_GSM_Decoder(ibuf,(unsigned short *) buf); // decodes 33 byte -> 160 short
  85     return 2*160;
  86   }
  87 }