workbench/classes/datatypes/wav/wave_mpeg.c

   1 /*
   2  *      wave.datatype
   3  *      (c) Fredrik Wikstrom (fredrik@a500.org)
   4  */
   5
   6 #include "wave_mpeg.h"
   7
   8 DEC_SETUPPROTO(SetupMPEG) {
   9         return OK;
  10 }
  11
  12 /* DEC_CLEANUPPROTO(CleanupMPEG) {
  13 } */
  14
  15 DECODERPROTO_v2(DecodeMPEG) {
  16         struct ClassBase * libBase = data->libBase;
  17         struct MPEGA_STREAM *mpas;
  18         struct Hook bshook = {0};
  19
  20         MPA_CTRL mpactrl = {
  21                 NULL,   // bitstream access hook
  22                 // layers 1 & 2 settings (mono, stereo)
  23                 { FALSE, { 2, 0, 44100 }, { 2, 0, 44100 } },
  24                 // layer 3 settings (mono, stereo)
  25                 { FALSE, { 2, 0, 44100 }, { 2, 0, 44100 } },
  26                 1, // check for validity at start
  27                 0 // size of bitstream buffer (0 -> default)
  28         };
  29
  30         bshook.h_Entry = (HOOKFUNC)bshook_func;
  31         bshook.h_SubEntry = (HOOKFUNC)data;
  32         bshook.h_Data = (APTR)file;
  33         mpactrl.bs_access = &bshook;
  34
  35         if (mpas = IMPEGA->MPEGA_open(NULL, &mpactrl)) {
  36                 WORD *pcm[2];
  37                 LONG pcm_count;
  38
  39                 pcm[0] = AllocVec(MPEGA_PCM_SIZE, MEMF_CLEAR);
  40                 pcm[1] = AllocVec(MPEGA_PCM_SIZE, MEMF_CLEAR);
  41
  42                 if (pcm[0] && pcm[1]) {
  43
  44                         while ((pcm_count = IMPEGA->MPEGA_decode_frame(mpas, pcm)) >= 0) {
  45                         }
  46
  47                 }
  48
  49                 FreeVec(pcm[0]);
  50                 FreeVec(pcm[1]);
  51         }
  52 }