apps/codecs/kss.c

   1
   2 /* Ripped off from Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ */
   3
   4 #include <codecs/lib/codeclib.h>
   5 #include "libgme/kss_emu.h"
   6
   7 CODEC_HEADER
   8
   9 /* Maximum number of bytes to process in one iteration */
  10 #define CHUNK_SIZE (1024*2)
  11
  12 static int16_t samples[CHUNK_SIZE] IBSS_ATTR;
  13 static struct Kss_Emu kss_emu IDATA_ATTR CACHEALIGN_ATTR;
  14
  15 /****************** rockbox interface ******************/
  16
  17 static void set_codec_track(int t) {
  18     Kss_start_track(&kss_emu, t);
  19
  20     /* for REPEAT_ONE we disable track limits */
  21     if (ci->global_settings->repeat_mode != REPEAT_ONE) {
  22         Track_set_fade(&kss_emu, Track_get_length( &kss_emu, t ), 4000);
  23     }
  24     ci->set_elapsed(t*1000); /* t is track no to display */
  25 }
  26
  27 /* this is the codec entry point */
  28 enum codec_status codec_main(enum codec_entry_call_reason reason)
  29 {
  30     if (reason == CODEC_LOAD) {
  31         /* we only render 16 bits */
  32         ci->configure(DSP_SET_SAMPLE_DEPTH, 16);
  33
  34         /* 44 Khz, Interleaved stereo */
  35         ci->configure(DSP_SET_FREQUENCY, 44100);
  36         ci->configure(DSP_SET_STEREO_MODE, STEREO_INTERLEAVED);
  37
  38         Kss_init(&kss_emu);
  39         Kss_set_sample_rate(&kss_emu, 44100);
  40     }
  41
  42     return CODEC_OK;
  43 }
  44
  45 /* this is called for each file to process */
  46 enum codec_status codec_run(void)
  47 {
  48     blargg_err_t err;
  49     uint8_t *buf;
  50     size_t n;
  51     int track;
  52     intptr_t param;
  53     uint32_t elapsed_time;
  54
  55     /* reset values */
  56     track = 0;
  57     elapsed_time = 0;
  58
  59     DEBUGF("KSS: next_track\n");
  60     if (codec_init()) {
  61         return CODEC_ERROR;
  62     }
  63
  64     codec_set_replaygain(ci->id3);
  65
  66     /* Read the entire file */
  67     DEBUGF("KSS: request file\n");
  68     ci->seek_buffer(0);
  69     buf = ci->request_buffer(&n, ci->filesize);
  70     if (!buf || n < (size_t)ci->filesize) {
  71         DEBUGF("KSS: file load failed\n");
  72         return CODEC_ERROR;
  73     }
  74
  75     if ((err = Kss_load_mem(&kss_emu, buf, ci->filesize))) {
  76         DEBUGF("KSS: Kss_load failed (%s)\n", err);
  77         return CODEC_ERROR;
  78     }
  79
  80     /* Update internal track count */
  81     if (kss_emu.m3u.size > 0)
  82         kss_emu.track_count = kss_emu.m3u.size;
  83
  84 next_track:
  85     set_codec_track(track);
  86
  87     /* The main decoder loop */
  88     while (1) {
  89         enum codec_command_action action = ci->get_command(&param);
  90
  91         if (action == CODEC_ACTION_HALT)
  92             break;
  93
  94         if (action == CODEC_ACTION_SEEK_TIME) {
  95                 track = param/1000;
  96                 ci->seek_complete();
  97                 if (track >= kss_emu.track_count) break;
  98                 goto next_track;
  99         }
 100
 101         /* Generate audio buffer */
 102         err = Kss_play(&kss_emu, CHUNK_SIZE, samples);
 103         if (err || kss_emu.track_ended) {
 104             track++;
 105             if (track >= kss_emu.track_count) break;
 106             goto next_track;
 107         }
 108
 109         ci->pcmbuf_insert(samples, NULL, CHUNK_SIZE >> 1);
 110     }
 111
 112     return CODEC_OK;
 113 }