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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 Dave Chapman
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* 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 <stdlib.h>
#include <ctype.h>
#include <inttypes.h>
#include "system.h"
#include "id3.h"
#include "metadata_common.h"
bool get_wave_metadata(int fd, struct mp3entry* id3)
{
/* Use the trackname part of the id3 structure as a temporary buffer */
unsigned char* buf = (unsigned char *)id3->path;
unsigned long totalsamples = 0;
unsigned long channels = 0;
unsigned long bitspersample = 0;
unsigned long numbytes = 0;
int read_bytes;
int i;
/* get RIFF chunk header */
if ((lseek(fd, 0, SEEK_SET) < 0)
|| ((read_bytes = read(fd, buf, 12)) < 12))
{
return false;
}
if ((memcmp(buf, "RIFF",4) != 0)
|| (memcmp(&buf[8], "WAVE", 4) !=0 ))
{
return false;
}
/* iterate over WAVE chunks until 'data' chunk */
while (true)
{
/* get chunk header */
if ((read_bytes = read(fd, buf, 8)) < 8)
return false;
/* chunkSize */
i = get_long_le(&buf[4]);
if (memcmp(buf, "fmt ", 4) == 0)
{
/* get rest of chunk */
if ((read_bytes = read(fd, buf, 16)) < 16)
return false;
i -= 16;
/* skipping wFormatTag */
/* wChannels */
channels = buf[2] | (buf[3] << 8);
/* dwSamplesPerSec */
id3->frequency = get_long_le(&buf[4]);
/* dwAvgBytesPerSec */
id3->bitrate = (get_long_le(&buf[8]) * 8) / 1000;
/* skipping wBlockAlign */
/* wBitsPerSample */
bitspersample = buf[14] | (buf[15] << 8);
}
else if (memcmp(buf, "data", 4) == 0)
{
numbytes = i;
break;
}
else if (memcmp(buf, "fact", 4) == 0)
{
/* dwSampleLength */
if (i >= 4)
{
/* get rest of chunk */
if ((read_bytes = read(fd, buf, 4)) < 4)
return false;
i -= 4;
totalsamples = get_long_le(buf);
}
}
/* seek to next chunk (even chunk sizes must be padded) */
if (i & 0x01)
i++;
if(lseek(fd, i, SEEK_CUR) < 0)
return false;
}
if ((numbytes == 0) || (channels == 0))
{
return false;
}
if (totalsamples == 0)
{
/* for PCM only */
totalsamples = numbytes
/ ((((bitspersample - 1) / 8) + 1) * channels);
}
id3->vbr = false; /* All WAV files are CBR */
id3->filesize = filesize(fd);
/* Calculate track length (in ms) and estimate the bitrate (in kbit/s) */
id3->length = ((int64_t) totalsamples * 1000) / id3->frequency;
return true;
}
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