1 /***************************************************************************
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
10 * Copyright (C) 2005 Thom Johansen
11 * Copyright (C) 2010 Andree Buschmann
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version 2
16 * of the License, or (at your option) any later version.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ****************************************************************************/
27 #include "metadata_common.h"
28 #include "metadata_parsers.h"
30 #include "replaygain.h"
31 #include "fixedpoint.h"
33 /* Needed for replay gain and clipping prevention of SV8 files. */
34 #define SV8_TO_SV7_CONVERT_GAIN (6482) /* 64.82 * 100, MPC_OLD_GAIN_REF */
35 #define SV8_TO_SV7_CONVERT_PEAK (23119) /* 256 * 20 * log10(32768) */
37 static int set_replaygain_sv7(struct mp3entry
* id3
,
42 long gain
= (int16_t) ((value
>> 16) & 0xffff);
43 long peak
= (uint16_t) (value
& 0xffff);
45 /* We use a peak value of 0 to indicate a given gain type isn't used. */
47 /* Save the ReplayGain data to id3-structure for further processing. */
48 used
+= parse_replaygain_int(album
, gain
* 512 / 100, peak
<< 9,
49 id3
, id3
->toc
+ used
, sizeof(id3
->toc
) - used
);
55 static int set_replaygain_sv8(struct mp3entry
* id3
,
61 gain
= (long)(SV8_TO_SV7_CONVERT_GAIN
- ((gain
*100)/256));
63 /* Transform SV8's logarithmic peak representation to the desired linear
64 * representation: linear = pow(10, peak/256/20).
66 * FP_BITS = 24 bits = desired fp representation for dsp routines
67 * FRAC_BITS = 12 bits = resolution used for fp_bits
68 * fp_factor(peak*(1<<FRAC_BITS)/256, FRAC_BITS) << (FP_BITS-FRAC_BITS)
70 peak
= (fp_factor((peak
-SV8_TO_SV7_CONVERT_PEAK
)*16, 12) << 12);
72 /* We use a peak value of 0 to indicate a given gain type isn't used. */
74 /* Save the ReplayGain data to id3-structure for further processing. */
75 used
+= parse_replaygain_int(album
, gain
* 512 / 100, peak
,
76 id3
, id3
->toc
+ used
, sizeof(id3
->toc
) - used
);
82 static int sv8_get_size(uint8_t *buffer
, int index
, uint64_t *p_size
)
88 tmp
= buffer
[index
++];
89 size
= (size
<< 7) | (tmp
& 0x7F);
90 } while((tmp
& 0x80));
96 bool get_musepack_metadata(int fd
, struct mp3entry
*id3
)
98 static const int32_t sfreqs
[4] = { 44100, 48000, 37800, 32000 };
100 uint64_t samples
= 0;
103 if (!skip_id3v2(fd
, id3
))
105 if (read(fd
, header
, 4*8) != 4*8) return false;
106 /* Musepack files are little endian, might need swapping */
107 for (i
= 1; i
< 8; i
++)
108 header
[i
] = letoh32(header
[i
]);
109 if (!memcmp(header
, "MP+", 3)) { /* Compare to sig "MP+" */
110 unsigned int streamversion
;
111 header
[0] = letoh32(header
[0]);
112 streamversion
= (header
[0] >> 24) & 15;
113 if (streamversion
== 7) {
114 unsigned int gapless
= (header
[5] >> 31) & 0x0001;
115 unsigned int last_frame_samples
= (header
[5] >> 20) & 0x07ff;
116 unsigned int bufused
= 0;
118 id3
->frequency
= sfreqs
[(header
[2] >> 16) & 0x0003];
119 samples
= (uint64_t)header
[1]*1152; /* 1152 is mpc frame size */
121 samples
-= 1152 - last_frame_samples
;
123 samples
-= 481; /* Musepack subband synth filter delay */
125 bufused
= set_replaygain_sv7(id3
, false, header
[3], bufused
);
126 bufused
= set_replaygain_sv7(id3
, true , header
[4], bufused
);
128 return false; /* only SV7 is allowed within a "MP+" signature */
130 } else if (!memcmp(header
, "MPCK", 4)) { /* Compare to sig "MPCK" */
131 uint8_t sv8_header
[32];
133 lseek(fd
, 4, SEEK_SET
);
134 if (read(fd
, sv8_header
, 2) != 2) return false; /* read frame ID */
135 if (!memcmp(sv8_header
, "SH", 2)) { /* Stream Header ID */
137 uint32_t streamversion
;
138 uint64_t size
= 0; /* tag size */
139 uint64_t dummy
= 0; /* used to dummy read data from header */
141 /* 4 bytes 'MPCK' + 2 'SH' */
142 lseek(fd
, 6, SEEK_SET
);
143 if (read(fd
, sv8_header
, 32) != 32) return false;
145 /* Read the size of 'SH'-tag */
146 k
= sv8_get_size(sv8_header
, k
, &size
);
151 /* Read stream version */
152 streamversion
= sv8_header
[k
++];
153 if (streamversion
!= 8) return false; /* Only SV8 is allowed. */
155 /* Number of samples */
156 k
= sv8_get_size(sv8_header
, k
, &samples
);
158 /* Number of leading zero-samples */
159 k
= sv8_get_size(sv8_header
, k
, &dummy
);
161 /* Sampling frequency */
162 id3
->frequency
= sfreqs
[(sv8_header
[k
++] >> 5) & 0x0003];
164 /* Number of channels */
165 id3
->channels
= (sv8_header
[k
++] >> 4) + 1;
167 /* Skip to next tag: k = size -2 */
170 if (!memcmp(sv8_header
+k
, "RG", 2)) { /* Replay Gain ID */
174 k
+= 2; /* 2 bytes 'RG' */
176 /* sv8_get_size must be called to skip the right amount of
177 * bits within the header data. */
178 k
= sv8_get_size(sv8_header
, k
, &size
);
180 /* Read and set replay gain */
181 if (sv8_header
[k
++] == 1) {
182 /* Title's peak and gain */
183 gain
= (int16_t) ((sv8_header
[k
]<<8) + sv8_header
[k
+1]); k
+= 2;
184 peak
= (uint16_t)((sv8_header
[k
]<<8) + sv8_header
[k
+1]); k
+= 2;
185 bufused
+= set_replaygain_sv8(id3
, false, gain
, peak
, bufused
);
187 /* Album's peak and gain */
188 gain
= (int16_t) ((sv8_header
[k
]<<8) + sv8_header
[k
+1]); k
+= 2;
189 peak
= (uint16_t)((sv8_header
[k
]<<8) + sv8_header
[k
+1]); k
+= 2;
190 bufused
+= set_replaygain_sv8(id3
, true , gain
, peak
, bufused
);
194 /* No sv8 stream header found */
198 return false; /* SV4-6 is not supported anymore */
202 /* Estimate bitrate, we should probably subtract the various header sizes
203 here for super-accurate results */
204 id3
->length
= ((int64_t) samples
* 1000) / id3
->frequency
;
206 if (id3
->length
<= 0)
208 logf("mpc length invalid!");
212 id3
->filesize
= filesize(fd
);
213 id3
->bitrate
= id3
->filesize
* 8 / id3
->length
;