rockbox/apps/metadata/mpc.c
Marcoen Hirschberg 2175d1edf6 split up the metadata parser
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@13637 a1c6a512-1295-4272-9138-f99709370657
2007-06-16 18:19:51 +00:00

118 lines
4.4 KiB
C

/***************************************************************************
* __________ __ ___.
* 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"
#include "logf.h"
#include "replaygain.h"
bool get_musepack_metadata(int fd, struct mp3entry *id3)
{
const int32_t sfreqs_sv7[4] = { 44100, 48000, 37800, 32000 };
uint32_t header[8];
uint64_t samples = 0;
int i;
if (!skip_id3v2(fd, id3))
return false;
if (read(fd, header, 4*8) != 4*8) return false;
/* Musepack files are little endian, might need swapping */
for (i = 1; i < 8; i++)
header[i] = letoh32(header[i]);
if (!memcmp(header, "MP+", 3)) { /* Compare to sig "MP+" */
unsigned int streamversion;
header[0] = letoh32(header[0]);
streamversion = (header[0] >> 24) & 15;
if (streamversion >= 8) {
return false; /* SV8 or higher don't exist yet, so no support */
} else if (streamversion == 7) {
unsigned int gapless = (header[5] >> 31) & 0x0001;
unsigned int last_frame_samples = (header[5] >> 20) & 0x07ff;
int track_gain, album_gain;
unsigned int bufused;
id3->frequency = sfreqs_sv7[(header[2] >> 16) & 0x0003];
samples = (uint64_t)header[1]*1152; /* 1152 is mpc frame size */
if (gapless)
samples -= 1152 - last_frame_samples;
else
samples -= 481; /* Musepack subband synth filter delay */
/* Extract ReplayGain data from header */
track_gain = (int16_t)((header[3] >> 16) & 0xffff);
id3->track_gain = get_replaygain_int(track_gain);
id3->track_peak = ((uint16_t)(header[3] & 0xffff)) << 9;
album_gain = (int16_t)((header[4] >> 16) & 0xffff);
id3->album_gain = get_replaygain_int(album_gain);
id3->album_peak = ((uint16_t)(header[4] & 0xffff)) << 9;
/* Write replaygain values to strings for use in id3 screen. We use
the XING header as buffer space since Musepack files shouldn't
need to use it in any other way */
id3->track_gain_string = (char *)id3->toc;
bufused = snprintf(id3->track_gain_string, 45,
"%d.%d dB", track_gain/100, abs(track_gain)%100);
id3->album_gain_string = (char *)id3->toc + bufused + 1;
bufused = snprintf(id3->album_gain_string, 45,
"%d.%d dB", album_gain/100, abs(album_gain)%100);
}
} else {
header[0] = letoh32(header[0]);
unsigned int streamversion = (header[0] >> 11) & 0x03FF;
if (streamversion != 4 && streamversion != 5 && streamversion != 6)
return false;
id3->frequency = 44100;
id3->track_gain = 0;
id3->track_peak = 0;
id3->album_gain = 0;
id3->album_peak = 0;
if (streamversion >= 5)
samples = (uint64_t)header[1]*1152; // 32 bit
else
samples = (uint64_t)(header[1] >> 16)*1152; // 16 bit
samples -= 576;
if (streamversion < 6)
samples -= 1152;
}
id3->vbr = true;
/* Estimate bitrate, we should probably subtract the various header sizes
here for super-accurate results */
id3->length = ((int64_t) samples * 1000) / id3->frequency;
if (id3->length <= 0)
{
logf("mpc length invalid!");
return false;
}
id3->filesize = filesize(fd);
id3->bitrate = id3->filesize * 8 / id3->length;
return true;
}