libmpcodecs/ad_hwmpa.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <unistd.h>
   5
   6 #include "config.h"
   7
   8 #include "mp_msg.h"
   9 #include "help_mp.h"
  10
  11 #include "libaf/af_format.h"
  12 #include "ad_internal.h"
  13
  14 #include "libmpdemux/mp3_hdr.h"
  15
  16 //based on ad_hwac3.c and ad_libmad.c
  17 static int isdts = -1;
  18
  19 static ad_info_t info =
  20 {
  21         "MPEG audio pass-through (fake decoder)",
  22         "hwmpa",
  23         "NicoDVB",
  24         "NicoDVB",
  25         "For hardware decoders"
  26 };
  27
  28 LIBAD_EXTERN(hwmpa)
  29
  30 static int mpa_sync(sh_audio_t *sh, int no_frames, int *n, int *chans, int *srate, int *spf, int *mpa_layer, int *br)
  31 {
  32         int cnt = 0, x = 0, len, frames_count;
  33
  34         frames_count = 0;
  35         do
  36         {
  37                 while(cnt + 4 < sh->a_in_buffer_len)
  38                 {
  39                         if(((sh->a_in_buffer[cnt] << 8) | sh->a_in_buffer[cnt+1]) & 0xffe0 != 0xffe0)
  40                                 continue;
  41                         x = mp_get_mp3_header(&(sh->a_in_buffer[cnt]), chans, srate, spf, mpa_layer, br);
  42                         if(x > 0)
  43                         {
  44                                 frames_count++;
  45                                 if(frames_count == no_frames)
  46                                 {
  47                                         *n = x;
  48                                         return cnt;
  49                                 }
  50                         }
  51                         cnt++;
  52                 }
  53                 len = demux_read_data(sh->ds,&sh->a_in_buffer[sh->a_in_buffer_len],sh->a_in_buffer_size-sh->a_in_buffer_len);
  54                 if(len > 0)
  55                         sh->a_in_buffer_len += len;
  56         } while(len > 0);
  57         mp_msg(MSGT_DECAUDIO,MSGL_INFO,"Cannot sync MPA frame: %d\r\n", len);
  58         return -1;
  59 }
  60
  61 static int preinit(sh_audio_t *sh)
  62 {
  63         sh->audio_out_minsize = 48;//check
  64         sh->audio_in_minsize = 4608;//check
  65         sh->sample_format = AF_FORMAT_MPEG2;
  66         return 1;
  67 }
  68
  69 static int init(sh_audio_t *sh)
  70 {
  71         int cnt, chans, srate, spf, mpa_layer, br, len;
  72
  73         if((cnt = mpa_sync(sh, 1, &len, &chans, &srate, &spf, &mpa_layer, &br)) < 0)
  74                 return 0;
  75
  76         sh->channels = chans;
  77         sh->samplerate = srate;
  78         sh->i_bps = br * 125;
  79         sh->samplesize = 2;
  80
  81         mp_msg(MSGT_DECAUDIO,MSGL_V,"AC_HWMPA initialized, bitrate: %d kb/s\r\n", len);
  82         return 1;
  83 }
  84
  85 static int decode_audio(sh_audio_t *sh,unsigned char *buf,int minlen,int maxlen)
  86 {
  87         int len, start, cnt2, tot;
  88         int chans, srate, spf, mpa_layer, br;
  89
  90         tot = cnt2 = 0;
  91         while(tot < minlen && tot+4608<=maxlen)
  92         {
  93                 start = mpa_sync(sh, 1, &len, &chans, &srate, &spf, &mpa_layer, &br);
  94                 if(start < 0)
  95                         break;
  96
  97                 if(start + len < sh->a_in_buffer_len && start + len >= maxlen)
  98                         break;
  99                 memcpy(&buf[cnt2], &(sh->a_in_buffer[start]), len);
 100                 cnt2 += len;
 101                 sh->a_in_buffer_len -= start + len;
 102                 memmove(sh->a_in_buffer, &(sh->a_in_buffer[start + len]), sh->a_in_buffer_len);
 103                 tot += start + len;
 104         }
 105
 106         return tot;
 107 }
 108
 109
 110 static int control(sh_audio_t *sh,int cmd,void* arg, ...)
 111 {
 112         int start, len, n;
 113
 114         switch(cmd)
 115         {
 116                 case ADCTRL_RESYNC_STREAM:
 117                         if(mpa_sync(sh, 1, &len, NULL, NULL, NULL, NULL, NULL) >= 0)
 118                                 return CONTROL_TRUE;
 119                         else
 120                                 return CONTROL_FALSE;
 121                 case ADCTRL_SKIP_FRAME:
 122                         start = mpa_sync(sh, 2, &len, NULL, NULL, NULL, NULL, NULL);
 123                         if(len < 0)
 124                                 return CONTROL_FALSE;
 125
 126                         sh->a_in_buffer_len -= start;
 127                         memmove(sh->a_in_buffer, &(sh->a_in_buffer[start]), sh->a_in_buffer_len);
 128                         return CONTROL_TRUE;
 129         }
 130         return CONTROL_UNKNOWN;
 131 }
 132
 133
 134 static void uninit(sh_audio_t *sh)
 135 {
 136 }