rockbox/lib/rbcodec/metadata/mpc.c
Sean Bartell cadb3627fc Add rbcodecplatform.h and rbcodecconfig.h.
librbcodec users must provide these two files when the library is built.
rbcodecconfig.h provides configuration #defines and basic types, and
will be included by public librbcodec headers, so it must not conflict
with the user's code. rbcodecplatform.h provides various OS functions,
and will only be included by source files and private headers. This
system is intended to provide maximum flexibility for use on embedded
systems, where no operating system headers are included. Unix systems
can just copy rbcodecconfig-example.h and rbcodecplatform-unix.h with
minimal changes.

Change-Id: I350a2274d173da391fd1ca00c4202e9760d91def
Reviewed-on: http://gerrit.rockbox.org/143
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
2012-05-03 14:49:35 +02:00

220 lines
7.9 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 Thom Johansen
* Copyright (C) 2010 Andree Buschmann
*
* 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 <string.h>
#include <stdio.h>
#include <inttypes.h>
#include "platform.h"
#include "metadata.h"
#include "metadata_common.h"
#include "metadata_parsers.h"
#include "logf.h"
#include "replaygain.h"
#include "fixedpoint.h"
/* Needed for replay gain and clipping prevention of SV8 files. */
#define SV8_TO_SV7_CONVERT_GAIN (6482) /* 64.82 * 100, MPC_OLD_GAIN_REF */
#define SV8_TO_SV7_CONVERT_PEAK (23119) /* 256 * 20 * log10(32768) */
static int set_replaygain_sv7(struct mp3entry* id3,
bool album,
long value,
long used)
{
long gain = (int16_t) ((value >> 16) & 0xffff);
long peak = (uint16_t) (value & 0xffff);
/* We use a peak value of 0 to indicate a given gain type isn't used. */
if (peak != 0) {
/* Save the ReplayGain data to id3-structure for further processing. */
parse_replaygain_int(album, gain * 512 / 100, peak << 9, id3);
}
return used;
}
static int set_replaygain_sv8(struct mp3entry* id3,
bool album,
long gain,
long peak,
long used)
{
gain = (long)(SV8_TO_SV7_CONVERT_GAIN - ((gain*100)/256));
/* Transform SV8's logarithmic peak representation to the desired linear
* representation: linear = pow(10, peak/256/20).
*
* FP_BITS = 24 bits = desired fp representation for dsp routines
* FRAC_BITS = 12 bits = resolution used for fp_bits
* fp_factor(peak*(1<<FRAC_BITS)/256, FRAC_BITS) << (FP_BITS-FRAC_BITS)
**/
peak = (fp_factor((peak-SV8_TO_SV7_CONVERT_PEAK)*16, 12) << 12);
/* We use a peak value of 0 to indicate a given gain type isn't used. */
if (peak != 0) {
/* Save the ReplayGain data to id3-structure for further processing. */
parse_replaygain_int(album, gain * 512 / 100, peak, id3);
}
return used;
}
static int sv8_get_size(uint8_t *buffer, int index, uint64_t *p_size)
{
unsigned char tmp;
uint64_t size = 0;
do {
tmp = buffer[index++];
size = (size << 7) | (tmp & 0x7F);
} while((tmp & 0x80));
*p_size = size;
return index;
}
bool get_musepack_metadata(int fd, struct mp3entry *id3)
{
static const int32_t sfreqs[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 == 7) {
unsigned int gapless = (header[5] >> 31) & 0x0001;
unsigned int last_frame_samples = (header[5] >> 20) & 0x07ff;
unsigned int bufused = 0;
id3->frequency = sfreqs[(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 */
bufused = set_replaygain_sv7(id3, false, header[3], bufused);
bufused = set_replaygain_sv7(id3, true , header[4], bufused);
id3->codectype = AFMT_MPC_SV7;
} else {
return false; /* only SV7 is allowed within a "MP+" signature */
}
} else if (!memcmp(header, "MPCK", 4)) { /* Compare to sig "MPCK" */
uint8_t sv8_header[32];
/* 4 bytes 'MPCK' */
lseek(fd, 4, SEEK_SET);
if (read(fd, sv8_header, 2) != 2) return false; /* read frame ID */
if (!memcmp(sv8_header, "SH", 2)) { /* Stream Header ID */
int32_t k = 0;
uint32_t streamversion;
uint64_t size = 0; /* tag size */
uint64_t dummy = 0; /* used to dummy read data from header */
/* 4 bytes 'MPCK' + 2 'SH' */
lseek(fd, 6, SEEK_SET);
if (read(fd, sv8_header, 32) != 32) return false;
/* Read the size of 'SH'-tag */
k = sv8_get_size(sv8_header, k, &size);
/* Skip crc32 */
k += 4;
/* Read stream version */
streamversion = sv8_header[k++];
if (streamversion != 8) return false; /* Only SV8 is allowed. */
/* Number of samples */
k = sv8_get_size(sv8_header, k, &samples);
/* Number of leading zero-samples */
k = sv8_get_size(sv8_header, k, &dummy);
/* Sampling frequency */
id3->frequency = sfreqs[(sv8_header[k++] >> 5) & 0x0003];
/* Number of channels */
id3->channels = (sv8_header[k++] >> 4) + 1;
/* Skip to next tag: k = size -2 */
k = size - 2;
if (!memcmp(sv8_header+k, "RG", 2)) { /* Replay Gain ID */
long peak, gain;
int bufused = 0;
k += 2; /* 2 bytes 'RG' */
/* sv8_get_size must be called to skip the right amount of
* bits within the header data. */
k = sv8_get_size(sv8_header, k, &size);
/* Read and set replay gain */
if (sv8_header[k++] == 1) {
/* Title's peak and gain */
gain = (int16_t) ((sv8_header[k]<<8) + sv8_header[k+1]); k += 2;
peak = (uint16_t)((sv8_header[k]<<8) + sv8_header[k+1]); k += 2;
bufused += set_replaygain_sv8(id3, false, gain, peak, bufused);
/* Album's peak and gain */
gain = (int16_t) ((sv8_header[k]<<8) + sv8_header[k+1]); k += 2;
peak = (uint16_t)((sv8_header[k]<<8) + sv8_header[k+1]); k += 2;
bufused += set_replaygain_sv8(id3, true , gain, peak, bufused);
}
}
id3->codectype = AFMT_MPC_SV8;
} else {
/* No sv8 stream header found */
return false;
}
} else {
return false; /* SV4-6 is not supported anymore */
}
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;
read_ape_tags(fd, id3);
return true;
}