rockbox/apps/metadata/wavpack.c
Daniel Stenberg 2acc0ac542 Updated our source code header to explicitly mention that we are GPL v2 or
later. We still need to hunt down snippets used that are not. 1324 modified
files...
http://www.rockbox.org/mail/archive/rockbox-dev-archive-2008-06/0060.shtml


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17847 a1c6a512-1295-4272-9138-f99709370657
2008-06-28 18:10:04 +00:00

143 lines
4.5 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id:$
*
* Copyright (C) 2007 David Bryant
*
* 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 <stdlib.h>
#include <ctype.h>
#include <inttypes.h>
#include "system.h"
#include "id3.h"
#include "metadata_common.h"
#include "metadata_parsers.h"
#include "logf.h"
#define ID_UNIQUE 0x3f
#define ID_LARGE 0x80
#define ID_SAMPLE_RATE 0x27
#define MONO_FLAG 4
#define HYBRID_FLAG 8
static const long wavpack_sample_rates [] =
{
6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,
32000, 44100, 48000, 64000, 88200, 96000, 192000
};
/* A simple parser to read basic information from a WavPack file. This
* now works with self-extrating WavPack files and also will scan the
* metadata for non-standard sampling rates. This no longer fails on
* WavPack files containing floating-point audio data because these are
* now converted to standard Rockbox format in the decoder.
*/
bool get_wavpack_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;
uint32_t totalsamples, blocksamples, flags;
int i;
for (i = 0; i < 256; ++i) {
/* at every 256 bytes into file, try to read a WavPack header */
if ((lseek(fd, i * 256, SEEK_SET) < 0) || (read(fd, buf, 32) < 32))
return false;
/* if valid WavPack 4 header version, break */
if (memcmp (buf, "wvpk", 4) == 0 && buf [9] == 4 &&
(buf [8] >= 2 && buf [8] <= 0x10))
break;
}
if (i == 256) {
logf ("Not a WavPack file");
return false;
}
id3->vbr = true; /* All WavPack files are VBR */
id3->filesize = filesize (fd);
totalsamples = get_long_le(&buf[12]);
blocksamples = get_long_le(&buf[20]);
flags = get_long_le(&buf[24]);
if (blocksamples) {
int srindx = ((buf [26] >> 7) & 1) + ((buf [27] << 1) & 14);
if (srindx == 15) {
uint32_t meta_bytes = buf [4] + (buf [5] << 8) + (buf [6] << 16) - 24;
uint32_t meta_size;
id3->frequency = 44100;
while (meta_bytes >= 6) {
if (read(fd, buf, 2) < 2)
break;
if (buf [0] & ID_LARGE) {
if (read(fd, buf + 2, 2) < 2)
break;
meta_size = (buf [1] << 1) + (buf [2] << 9) + (buf [3] << 17);
meta_bytes -= meta_size + 4;
}
else {
meta_size = buf [1] << 1;
meta_bytes -= meta_size + 2;
if ((buf [0] & ID_UNIQUE) == ID_SAMPLE_RATE) {
if (meta_size == 4 && read(fd, buf + 2, 4) == 4)
id3->frequency = buf [2] + (buf [3] << 8) + (buf [4] << 16);
break;
}
}
if (meta_size > 0 && lseek(fd, meta_size, SEEK_CUR) < 0)
break;
}
}
else
id3->frequency = wavpack_sample_rates[srindx];
/* if the total number of samples is unknown, make a guess on the high side (for now) */
if (totalsamples == (uint32_t) -1) {
totalsamples = filesize (fd) * 3;
if (!(flags & HYBRID_FLAG))
totalsamples /= 2;
if (!(flags & MONO_FLAG))
totalsamples /= 2;
}
id3->length = ((int64_t) totalsamples * 1000) / id3->frequency;
id3->bitrate = filesize (fd) / (id3->length / 8);
return true;
}
return false;
}