apps/codecs/wavpack.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 David Bryant
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include "codeclib.h"
  23 #include "libwavpack/wavpack.h"
  24
  25 CODEC_HEADER
  26
  27 #define BUFFER_SIZE 4096
  28
  29 static int32_t temp_buffer [BUFFER_SIZE] IBSS_ATTR;
  30
  31 static int32_t read_callback (void *buffer, int32_t bytes)
  32 {
  33     int32_t retval = ci->read_filebuf (buffer, bytes);
  34     ci->set_offset(ci->curpos);
  35     return retval;
  36 }
  37
  38 /* this is the codec entry point */
  39 enum codec_status codec_main(enum codec_entry_call_reason reason)
  40 {
  41     if (reason == CODEC_LOAD) {
  42         /* Generic codec initialisation */
  43         ci->configure(DSP_SET_SAMPLE_DEPTH, 28);
  44     }
  45
  46     return CODEC_OK;
  47 }
  48
  49 /* this is called for each file to process */
  50 enum codec_status codec_run(void)
  51 {
  52     WavpackContext *wpc;
  53     char error [80];
  54     /* rockbox: comment 'set but unused' variables
  55     int bps;
  56     */
  57     int nchans, sr_100;
  58     intptr_t param;
  59
  60     if (codec_init())
  61         return CODEC_ERROR;
  62
  63     ci->seek_buffer (ci->id3->offset);
  64
  65     /* Create a decoder instance */
  66     wpc = WavpackOpenFileInput (read_callback, error);
  67
  68     if (!wpc)
  69         return CODEC_ERROR;
  70
  71     ci->configure(DSP_SWITCH_FREQUENCY, WavpackGetSampleRate (wpc));
  72     codec_set_replaygain(ci->id3);
  73     /* bps = WavpackGetBytesPerSample (wpc); */
  74     nchans = WavpackGetReducedChannels (wpc);
  75     ci->configure(DSP_SET_STEREO_MODE, nchans == 2 ? STEREO_INTERLEAVED : STEREO_MONO);
  76     sr_100 = ci->id3->frequency / 100;
  77
  78     ci->set_elapsed (0);
  79
  80     /* The main decoder loop */
  81
  82     while (1) {
  83         int32_t nsamples;
  84         enum codec_command_action action = ci->get_command(&param);
  85
  86         if (action == CODEC_ACTION_HALT)
  87             break;
  88
  89         if (action == CODEC_ACTION_SEEK_TIME) {
  90             int curpos_ms = WavpackGetSampleIndex (wpc) / sr_100 * 10;
  91             int n, d, skip;
  92
  93             if (param > curpos_ms) {
  94                 n = param - curpos_ms;
  95                 d = ci->id3->length - curpos_ms;
  96                 skip = (int)((int64_t)(ci->filesize - ci->curpos) * n / d);
  97                 ci->seek_buffer (ci->curpos + skip);
  98             }
  99             else if (curpos_ms != 0) {
 100                 n = curpos_ms - param;
 101                 d = curpos_ms;
 102                 skip = (int)((int64_t) ci->curpos * n / d);
 103                 ci->seek_buffer (ci->curpos - skip);
 104             }
 105
 106             wpc = WavpackOpenFileInput (read_callback, error);
 107             if (!wpc)
 108             {
 109                 ci->seek_complete();
 110                 break;
 111             }
 112
 113             ci->set_elapsed (WavpackGetSampleIndex (wpc) / sr_100 * 10);
 114             ci->seek_complete();
 115         }
 116
 117         nsamples = WavpackUnpackSamples (wpc, temp_buffer, BUFFER_SIZE / nchans);
 118
 119         if (!nsamples)
 120             break;
 121
 122         ci->pcmbuf_insert (temp_buffer, NULL, nsamples);
 123         ci->set_elapsed (WavpackGetSampleIndex (wpc) / sr_100 * 10);
 124     }
 125
 126     return CODEC_OK;
 127 }