libmpcodecs/ad_dvdpcm.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 "mp_msg.h"
  25 #include "help_mp.h"
  26 #include "ad_internal.h"
  27
  28 static const ad_info_t info =
  29 {
  30         "Uncompressed DVD/VOB LPCM audio decoder",
  31         "dvdpcm",
  32         "Nick Kurshev",
  33         "A'rpi",
  34         ""
  35 };
  36
  37 LIBAD_EXTERN(dvdpcm)
  38
  39 static int init(sh_audio_t *sh)
  40 {
  41 /* DVD PCM Audio:*/
  42     sh->i_bps = 0;
  43     if(sh->codecdata_len==3){
  44         // we have LPCM header:
  45         unsigned char h=sh->codecdata[1];
  46         sh->channels=1+(h&7);
  47         switch((h>>4)&3){
  48         case 0: sh->samplerate=48000;break;
  49         case 1: sh->samplerate=96000;break;
  50         case 2: sh->samplerate=44100;break;
  51         case 3: sh->samplerate=32000;break;
  52         }
  53         switch ((h >> 6) & 3) {
  54           case 0:
  55             sh->sample_format = AF_FORMAT_S16_BE;
  56             sh->samplesize = 2;
  57             break;
  58           case 1:
  59             mp_msg(MSGT_DECAUDIO, MSGL_INFO, MSGTR_SamplesWanted);
  60             sh->i_bps = sh->channels * sh->samplerate * 5 / 2;
  61           case 2:
  62             sh->sample_format = AF_FORMAT_S24_BE;
  63             sh->samplesize = 3;
  64             break;
  65           default:
  66             sh->sample_format = AF_FORMAT_S16_BE;
  67             sh->samplesize = 2;
  68         }
  69     } else {
  70         // use defaults:
  71         sh->channels=2;
  72         sh->samplerate=48000;
  73         sh->sample_format = AF_FORMAT_S16_BE;
  74         sh->samplesize = 2;
  75     }
  76     if (!sh->i_bps)
  77     sh->i_bps = sh->samplesize * sh->channels * sh->samplerate;
  78     return 1;
  79 }
  80
  81 static int preinit(sh_audio_t *sh)
  82 {
  83   sh->audio_out_minsize=2048;
  84   return 1;
  85 }
  86
  87 static void uninit(sh_audio_t *sh)
  88 {
  89 }
  90
  91 static int control(sh_audio_t *sh,int cmd,void* arg, ...)
  92 {
  93   int skip;
  94     switch(cmd)
  95     {
  96       case ADCTRL_SKIP_FRAME:
  97         skip=sh->i_bps/16;
  98         skip=skip&(~3);
  99         demux_read_data(sh->ds,NULL,skip);
 100         return CONTROL_TRUE;
 101     }
 102   return CONTROL_UNKNOWN;
 103 }
 104
 105 static int decode_audio(sh_audio_t *sh_audio,unsigned char *buf,int minlen,int maxlen)
 106 {
 107   int j,len;
 108   if (sh_audio->samplesize == 3) {
 109     if (((sh_audio->codecdata[1] >> 6) & 3) == 1) {
 110       // 20 bit
 111       // not sure if the "& 0xf0" and "<< 4" are the right way around
 112       // can somebody clarify?
 113       for (j = 0; j < minlen; j += 12) {
 114         char tmp[10];
 115         len = demux_read_data(sh_audio->ds, tmp, 10);
 116         if (len < 10) break;
 117         // first sample
 118         buf[j + 0] = tmp[0];
 119         buf[j + 1] = tmp[1];
 120         buf[j + 2] = tmp[8] & 0xf0;
 121         // second sample
 122         buf[j + 3] = tmp[2];
 123         buf[j + 4] = tmp[3];
 124         buf[j + 5] = tmp[8] << 4;
 125         // third sample
 126         buf[j + 6] = tmp[4];
 127         buf[j + 7] = tmp[5];
 128         buf[j + 8] = tmp[9] & 0xf0;
 129         // fourth sample
 130         buf[j + 9] = tmp[6];
 131         buf[j + 10] = tmp[7];
 132         buf[j + 11] = tmp[9] << 4;
 133       }
 134       len = j;
 135     } else {
 136       // 24 bit
 137       for (j = 0; j < minlen; j += 12) {
 138         char tmp[12];
 139         len = demux_read_data(sh_audio->ds, tmp, 12);
 140         if (len < 12) break;
 141         // first sample
 142         buf[j + 0] = tmp[0];
 143         buf[j + 1] = tmp[1];
 144         buf[j + 2] = tmp[8];
 145         // second sample
 146         buf[j + 3] = tmp[2];
 147         buf[j + 4] = tmp[3];
 148         buf[j + 5] = tmp[9];
 149         // third sample
 150         buf[j + 6] = tmp[4];
 151         buf[j + 7] = tmp[5];
 152         buf[j + 8] = tmp[10];
 153         // fourth sample
 154         buf[j + 9] = tmp[6];
 155         buf[j + 10] = tmp[7];
 156         buf[j + 11] = tmp[11];
 157       }
 158       len = j;
 159     }
 160   } else
 161   len=demux_read_data(sh_audio->ds,buf,(minlen+3)&(~3));
 162   return len;
 163 }