apps/codecs/vorbis.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 Björn Stenberg
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19
  20 #include "codeclib.h"
  21 #include "Tremor/ivorbisfile.h"
  22 #include "Tremor/ogg.h"
  23
  24 CODEC_HEADER
  25
  26 /* Some standard functions and variables needed by Tremor */
  27
  28 size_t read_handler(void *ptr, size_t size, size_t nmemb, void *datasource)
  29 {
  30     (void)datasource;
  31     return ci->read_filebuf(ptr, nmemb*size);
  32 }
  33
  34 int initial_seek_handler(void *datasource, ogg_int64_t offset, int whence)
  35 {
  36     (void)datasource;
  37     (void)offset;
  38     (void)whence;
  39     return -1;
  40 }
  41
  42 int seek_handler(void *datasource, ogg_int64_t offset, int whence)
  43 {
  44     (void)datasource;
  45
  46     if (whence == SEEK_CUR) {
  47         offset += ci->curpos;
  48     } else if (whence == SEEK_END) {
  49         offset += ci->filesize;
  50     }
  51
  52     if (ci->seek_buffer(offset)) {
  53         return 0;
  54     }
  55
  56     return -1;
  57 }
  58
  59 int close_handler(void *datasource)
  60 {
  61     (void)datasource;
  62     return 0;
  63 }
  64
  65 long tell_handler(void *datasource)
  66 {
  67     (void)datasource;
  68     return ci->curpos;
  69 }
  70
  71 /* This sets the DSP parameters based on the current logical bitstream
  72  * (sampling rate, number of channels, etc).  It also tries to guess
  73  * reasonable buffer parameters based on the current quality setting.
  74  */
  75 bool vorbis_set_codec_parameters(OggVorbis_File *vf)
  76 {
  77     vorbis_info *vi;
  78
  79     vi = ov_info(vf, -1);
  80
  81     if (vi == NULL) {
  82         //ci->splash(HZ*2, "Vorbis Error");
  83         return false;
  84     }
  85
  86     ci->configure(DSP_SWITCH_FREQUENCY, ci->id3->frequency);
  87     codec_set_replaygain(ci->id3);
  88
  89     if (vi->channels == 2) {
  90           ci->configure(DSP_SET_STEREO_MODE, STEREO_NONINTERLEAVED);
  91     } else if (vi->channels == 1) {
  92           ci->configure(DSP_SET_STEREO_MODE, STEREO_MONO);
  93     }
  94
  95     return true;
  96 }
  97
  98 /* this is the codec entry point */
  99 enum codec_status codec_main(void)
 100 {
 101     ov_callbacks callbacks;
 102     OggVorbis_File vf;
 103     ogg_int32_t **pcm;
 104
 105     int error;
 106     long n;
 107     int current_section;
 108     int previous_section = -1;
 109     int eof;
 110     ogg_int64_t vf_offsets[2];
 111     ogg_int64_t vf_dataoffsets;
 112     ogg_uint32_t vf_serialnos;
 113     ogg_int64_t vf_pcmlengths[2];
 114
 115     ci->configure(DSP_SET_SAMPLE_DEPTH, 24);
 116     /* Note: These are sane defaults for these values.  Perhaps
 117      * they should be set differently based on quality setting
 118      */
 119
 120 /* We need to flush reserver memory every track load. */
 121 next_track:
 122     if (codec_init()) {
 123         error = CODEC_ERROR;
 124         goto exit;
 125     }
 126     ogg_malloc_init();
 127
 128     while (!*ci->taginfo_ready && !ci->stop_codec)
 129         ci->sleep(1);
 130
 131     /* Create a decoder instance */
 132     callbacks.read_func = read_handler;
 133     callbacks.seek_func = initial_seek_handler;
 134     callbacks.tell_func = tell_handler;
 135     callbacks.close_func = close_handler;
 136
 137     /* Open a non-seekable stream */
 138     error = ov_open_callbacks(ci, &vf, NULL, 0, callbacks);
 139
 140     /* If the non-seekable open was successful, we need to supply the missing
 141      * data to make it seekable.  This is a hack, but it's reasonable since we
 142      * don't want to run the whole file through the buffer before we start
 143      * playing.  Using Tremor's seekable open routine would cause us to do
 144      * this, so we pretend not to be seekable at first.  Then we fill in the
 145      * missing fields of vf with 1) information in ci->id3, and 2) info
 146      * obtained by Tremor in the above ov_open call.
 147      *
 148      * Note that this assumes there is only ONE logical Vorbis bitstream in our
 149      * physical Ogg bitstream.  This is verified in metadata.c, well before we
 150      * get here.
 151      */
 152     if (!error) {
 153          vf.offsets = vf_offsets;
 154          vf.dataoffsets = &vf_dataoffsets;
 155          vf.serialnos = &vf_serialnos;
 156          vf.pcmlengths = vf_pcmlengths;
 157
 158          vf.offsets[0] = 0;
 159          vf.offsets[1] = ci->id3->filesize;
 160          vf.dataoffsets[0] = vf.offset;
 161          vf.pcmlengths[0] = 0;
 162          vf.pcmlengths[1] = ci->id3->samples;
 163          vf.serialnos[0] = vf.current_serialno;
 164          vf.callbacks.seek_func = seek_handler;
 165          vf.seekable = 1;
 166          vf.end = ci->id3->filesize;
 167          vf.ready_state = OPENED;
 168          vf.links = 1;
 169     } else {
 170          //ci->logf("ov_open: %d", error);
 171          error = CODEC_ERROR;
 172          goto done;
 173     }
 174
 175     if (ci->id3->offset) {
 176         ci->advance_buffer(ci->id3->offset);
 177         ov_raw_seek(&vf, ci->id3->offset);
 178         ci->set_elapsed(ov_time_tell(&vf));
 179         ci->set_offset(ov_raw_tell(&vf));
 180     }
 181
 182     eof = 0;
 183     while (!eof) {
 184         ci->yield();
 185         if (ci->stop_codec || ci->new_track)
 186             break;
 187
 188         if (ci->seek_time) {
 189             if (ov_time_seek(&vf, ci->seek_time - 1)) {
 190                 //ci->logf("ov_time_seek failed");
 191             }
 192             ci->seek_complete();
 193         }
 194
 195         /* Read host-endian signed 24-bit PCM samples */
 196         n = ov_read_fixed(&vf, &pcm, 1024, &current_section);
 197
 198         /* Change DSP and buffer settings for this bitstream */
 199         if (current_section != previous_section) {
 200             if (!vorbis_set_codec_parameters(&vf)) {
 201                 error = CODEC_ERROR;
 202                 goto done;
 203             } else {
 204                 previous_section = current_section;
 205             }
 206         }
 207
 208         if (n == 0) {
 209             eof = 1;
 210         } else if (n < 0) {
 211             DEBUGF("Error decoding frame\n");
 212         } else {
 213             ci->pcmbuf_insert(pcm[0], pcm[1], n);
 214             ci->set_offset(ov_raw_tell(&vf));
 215             ci->set_elapsed(ov_time_tell(&vf));
 216         }
 217     }
 218     error = CODEC_OK;
 219
 220 done:
 221     if (ci->request_next_track()) {
 222         /* Clean things up for the next track */
 223         vf.dataoffsets = NULL;
 224         vf.offsets = NULL;
 225         vf.serialnos = NULL;
 226         vf.pcmlengths = NULL;
 227         ov_clear(&vf);
 228         previous_section = -1;
 229         goto next_track;
 230     }
 231
 232 exit:
 233     return error;
 234 }
 235