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
  18 static const ad_info_t info =
  19 {
  20         "MPEG audio pass-through (fake decoder)",
  21         "hwmpa",
  22         "NicoDVB",
  23         "NicoDVB",
  24         "For hardware decoders"
  25 };
  26
  27 LIBAD_EXTERN(hwmpa)
  28
  29 static int mpa_sync(sh_audio_t *sh, int no_frames, int *n, int *chans, int *srate, int *spf, int *mpa_layer, int *br)
  30 {
  31         int cnt = 0, x = 0, len, frames_count;
  32
  33         frames_count = 0;
  34         do
  35         {
  36                 while(cnt + 4 < sh->a_in_buffer_len)
  37                 {
  38                         x = mp_get_mp3_header(&(sh->a_in_buffer[cnt]), chans, srate, spf, mpa_layer, br);
  39                         if(x > 0)
  40                         {
  41                                 frames_count++;
  42                                 if(frames_count == no_frames)
  43                                 {
  44                                         *n = x;
  45                                         return cnt;
  46                                 }
  47                         }
  48                         cnt++;
  49                 }
  50                 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);
  51                 if(len > 0)
  52                         sh->a_in_buffer_len += len;
  53         } while(len > 0);
  54         mp_msg(MSGT_DECAUDIO,MSGL_INFO,"Cannot sync MPA frame: %d\r\n", len);
  55         return -1;
  56 }
  57
  58 static int preinit(sh_audio_t *sh)
  59 {
  60         sh->audio_out_minsize = 4608;//check
  61         sh->audio_in_minsize = 4608;//check
  62         sh->sample_format = AF_FORMAT_MPEG2;
  63         return 1;
  64 }
  65
  66 static int init(sh_audio_t *sh)
  67 {
  68         int cnt, chans, srate, spf, mpa_layer, br, len;
  69
  70         if((cnt = mpa_sync(sh, 1, &len, &chans, &srate, &spf, &mpa_layer, &br)) < 0)
  71                 return 0;
  72
  73         sh->channels = chans;
  74         sh->samplerate = srate;
  75         sh->i_bps = br * 125;
  76         sh->samplesize = 2;
  77
  78         mp_msg(MSGT_DECAUDIO,MSGL_V,"AC_HWMPA initialized, bitrate: %d kb/s\r\n", len);
  79         return 1;
  80 }
  81
  82 static int decode_audio(sh_audio_t *sh,unsigned char *buf,int minlen,int maxlen)
  83 {
  84         int len, start, tot;
  85         int chans, srate, spf, mpa_layer, br;
  86         int tot2;
  87
  88         tot = tot2 = 0;
  89
  90         while(tot2 < maxlen)
  91         {
  92                 start = mpa_sync(sh, 1, &len, &chans, &srate, &spf, &mpa_layer, &br);
  93                 if(start < 0 || tot2 + spf * 2 * chans > maxlen)
  94                         break;
  95
  96                 if(start + len > sh->a_in_buffer_len)
  97                 {
  98                         int l;
  99                         l = FFMIN(sh->a_in_buffer_size - sh->a_in_buffer_len, start + len);
 100                         l = demux_read_data(sh->ds,&sh->a_in_buffer[sh->a_in_buffer_len], l);
 101                         if(! l)
 102                                 break;
 103                         sh->a_in_buffer_len += l;
 104                         continue;
 105                 }
 106
 107                 memcpy(&buf[tot], &(sh->a_in_buffer[start]), len);
 108                 tot += len;
 109
 110                 sh->a_in_buffer_len -= start + len;
 111                 memmove(sh->a_in_buffer, &(sh->a_in_buffer[start + len]), sh->a_in_buffer_len);
 112                 tot2 += spf * 2 * chans;
 113
 114                 /* HACK: seems to fix most A/V sync issues */
 115                 break;
 116         }
 117
 118         memset(&buf[tot], 0, tot2-tot);
 119         return tot2;
 120 }
 121
 122
 123 static int control(sh_audio_t *sh,int cmd,void* arg, ...)
 124 {
 125         int start, len;
 126
 127         switch(cmd)
 128         {
 129                 case ADCTRL_RESYNC_STREAM:
 130                         if(mpa_sync(sh, 1, &len, NULL, NULL, NULL, NULL, NULL) >= 0)
 131                                 return CONTROL_TRUE;
 132                         else
 133                                 return CONTROL_FALSE;
 134                 case ADCTRL_SKIP_FRAME:
 135                         start = mpa_sync(sh, 2, &len, NULL, NULL, NULL, NULL, NULL);
 136                         if(len < 0)
 137                                 return CONTROL_FALSE;
 138
 139                         sh->a_in_buffer_len -= start;
 140                         memmove(sh->a_in_buffer, &(sh->a_in_buffer[start]), sh->a_in_buffer_len);
 141                         return CONTROL_TRUE;
 142         }
 143         return CONTROL_UNKNOWN;
 144 }
 145
 146
 147 static void uninit(sh_audio_t *sh)
 148 {
 149 }