iTunesSD3gen

Here it is. The reason for this wiki. The third generation shuffle iTunesSD format.
Just like in the iTunesDB the default size for integer numbers seems to be 32 bit. In earlier iTunesSD files it was a rather odd 24 bit.
Like the iTunesDB new third generation shuffle's iTunesSD is little endian. Earlier iTunesSD files were big endian.

Little endian means that the numbers start with the lowest byte. So a value of 0x12345678 (decimal 305419896) will be written in the iTunesSD file as 78 56 34 12.
Apparently the apple developers liked to look at their files with a hex viewer to. At least they choose the magic numbers for their headers in a way that their ASCII representation tells you its purpose. So the database header starts with a magic number 0x73686462 (dec. 1936221282). Not an easy number to remember. But translating those bytes one by one into ASCII you get "s" "h" "d" "b", which to me looks like "shuffle database". The little endian storage format changes the byte order so that the first characters of the new iTunesSD are in fact "bdhs", but now you know how we came up with the names for those separate elements.

Here's the general layout of an iTunesSD file:

bdhs Shuffle Database

Field
 Size
 Description
 Data
 Hexdump
header_id
 4
 Header
 shdb
 62 64 68 73
unknown_1
 4
 ?
 0x03000002
 03 00 00 02
header_length
 4
 size of this header
 64
 40 00 00 00
total_no_of_tracks
 4
126
 7e 00 00 00
total_no_of_playlists
 4
10
 0a 00 00 00
unknown_2
 8
0x0000 0000 0000 0000
 00 00 00 00 00 00 00 00
max_volume
 1
 0x00 do not limit the volume
0x03 is the min setting
0x20 is the max setting
 0x00
 00
voiceover_enabled
 1
1
 01
unknown_3
 2
0x0000
 00 00
total_no_of_tracks2
 4
 Does not include podcasts or audiobooks in the count.
 126
 7e 00 00 00
track_header_chunk_offset
 4
0x00000040
 40 00 00 00
playlist_header_chunk_offset
 4
0x0000b964
 64 b9 00 00
unknown_4
 20
0x0000 0000 0000 0000 0000
0000 0000 0000 0000 0000
 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00

Tracks Header

Field
 Size
 Data
 Hexdump
header_id
 4
 shth
 68 74 68 73
total_length
 4
 524
 0c 02 00 00
number_of_tracks
 4
 126
 7e 00 00 00
unknown_1
 8
 0x0000 0000 0000 0000
 00 00 00 00 00 00 00 00
offset_of_track_chunk_0
 4
 0x0000024c
 4c 02 00 00
offset_of_track_chunk_1
 4
 0x000003c0
 c0 03 00 00
offset_of_track_chunk_2
 4
 0x00000534
 34 05 00 00
offset_of_track_chunk_3
 4
 0x000006a8
 a8 06 00 00
offset_of_track_chunk_4
 4
 0x0000081c
 1c 08 00 00
...
...
 ...


TrackX


Field
 Size
 Description
 Data
 Hexdump
header_id
 4
shtr
 72 74 68 73
total_length
 4
372
 74 01 00 00
start_at_pos_ms
 4
0
 00 00 00 00
stop_at_pos_ms
 4
 Rythmbox IPod plugin sets this value always 0.
 112169
 29 b6 01 00
volume_gain
 4
0x00000000
 00 00 00 00
filetype
 4
 Type 1 are mpeg, mp3 files
Type 2 arere aac, mp4, m4a files
Type 4 are wav files
 1 (MP3)
 01 00 00 00
filename
 256
/iPod_Control/Music/F02/NNCN.mp3
 2f 69 50 6f 64 5f 43 6f 6e 74 72 6f 6c 2f 4d 75
73 69 63 2f 46 30 32 2f 4e 4e 43 4e 2e 6d 70 33
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Bookmark
 4
 In milliseconds
 0x00000000
 00 00 00 00
dont_skip_on_shuffle
 1
 If all songs in a playlist don't have this bit set the playlist is skipped when the ipod is set to shuffle and a playlist is being chosen.
It seems to be ignored when shuffling within a playlist!
 1
 01
remember_playing_pos
 1
0
 00
part_of_uninterruptable_album
 1
0
 00
unknown_1
 1
0x00
 00
pregap
 4
0x240 = 576
 40 02 00 00
postgap
 4
0xc9c= 3228
 9c 0c 00 00
number_of_samples
 4
0x4b6c24 = 4942884
 24 6c 4b 00
unknown_file_related_data1
 4
0
 00 00 00 00
gapless_data
 4
0x24a2a2 = 2400930
 a2 a2 24 00
unknown_file_related_data2
 4
0
 00 00 00 00
Album ID
 4
0x0000007f
 7f 00 00 00
track_number
 2
1
 01 00
disc_number
 2
0
 00 00
unknown_2
 8
0x0000 0000 0000 0000
 00 00 00 00 00 00 00 00
dbid
 8
 Serves as the filename for the voiceover
 0xdfa209b7ce6f2db9
 b9 2d 6f ce b7 09 a2 df
Artist ID
 4
0x00000146
 46 01 00 00
unknown_3
 32
0x0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Playlist Header


Field
 Size
 Description
 Data
 Hexdump
header_id
 4
shph
 68 70 68 73
total_length
 4

20 00 00 00
number_of_playlists
 4?
3
 03 00 00 00
number_of_playlists_1
 2
 The number of non-podcast playlists, 0xffff if all playlists are not podcast playlists.
 0xffff
 ff ff
number_of_playlists_2
 2
 The number of master playlists, 0xffff if all playlists are not master playlists.
 0x0100
 01 00
number_of_playlists_3
 2
 The number of non-audiobook playlists, 0xffff if all playlists are not audiobook playlists.
 0xffff
 ff ff
unknown_2
 2

00 00
offset_of_playlist_1
 4
0x00015b14
 14 5b 01 00
offset_of_playlist_2
 4
0x00015ef0
 f0 5e 01 00
...

...
 ...

PlaylistX


Field
 Size
 Description
 Data
 Hexdump
header_id
 4
shpl
 6c 70 68 73
total_length
 4

dc 03 00 00
number_of_songs
 4
236
 ec 00 00 00
number_of_songs2
 4
 Number of non podcast or audiobook songs.
 236
 ec 00 00 00
dbid
 8
 Serves as the filename for the voiceover
 6bed
 48 4d 19 eb 4e 34 ed 6b
type
 4
 1 is the master playlist
2 is a normal playlist
3 is a podcast playlist
4 is a audiobook playlist
 2
 02 00 00 00
unknown_1
 16

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
playlist_track_1
 4
118
 76 00 00 00
playlist_track_2
 4
119
 77 00 00 00
...

...
 ...
A dbid of all zeros yields a voiceover of All songs. Also playlist dbids without a corresponding voiceover file will yield a voiceover of playlist n or audiobook n where n is the playlist number. The shuffle assumes the podcast playlist is last.

The iTunesStats file is also different in the 3gen iPod.

Original Source: http://shuffle3db.wikispaces.com/iTunesSD3gen (expired)