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