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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2010 Yoshihisa Uchida
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include "system.h"
#include "metadata.h"
#include "metadata_common.h"
#include "metadata_parsers.h"
#include "logf.h"
static const unsigned char bitspersamples[9] = {
0, /* encoding */
8, /* 1: G.711 MULAW */
8, /* 2: Linear PCM 8bit */
16, /* 3: Linear PCM 16bit */
24, /* 4: Linear PCM 24bit */
32, /* 5: Linear PCM 32bit */
32, /* 6: IEEE float 32bit */
64, /* 7: IEEE float 64bit */
/* encoding 8 - 26 unsupported. */
8, /* 27: G.711 ALAW */
};
static inline unsigned char get_au_bitspersample(unsigned int encoding)
{
if (encoding < 8)
return bitspersamples[encoding];
else if (encoding == 27)
return bitspersamples[8];
return 0;
}
bool get_au_metadata(int fd, struct mp3entry* id3)
{
/* temporary buffer */
unsigned char* buf = (unsigned char *)id3->path;
unsigned long numbytes = 0;
int offset;
id3->vbr = false; /* All Sun audio files are CBR */
id3->filesize = filesize(fd);
id3->length = 0;
lseek(fd, 0, SEEK_SET);
if ((read(fd, buf, 24) < 24) || (memcmp(buf, ".snd", 4) != 0))
{
/*
* no header
*
* frequency: 8000 Hz
* bits per sample: 8 bit
* channel: mono
*/
numbytes = id3->filesize;
id3->frequency = 8000;
id3->bitrate = 8;
}
else
{
/* parse header */
/* data offset */
offset = get_long_be(buf + 4);
if (offset < 24)
{
DEBUGF("CODEC_ERROR: sun audio offset size is small: %d\n", offset);
return false;
}
/* data size */
numbytes = get_long_be(buf + 8);
if (numbytes == (uint32_t)0xffffffff)
numbytes = id3->filesize - offset;
id3->frequency = get_long_be(buf + 16);
id3->bitrate = get_au_bitspersample(get_long_be(buf + 12)) * get_long_be(buf + 20)
* id3->frequency / 1000;
}
/* Calculate track length [ms] */
if (id3->bitrate)
id3->length = (numbytes << 3) / id3->bitrate;
return true;
}
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