Principle of mp3 and file format analysis. Part 3
The ID3 standard MP3 frame header does not consider storing complex information such as song title, author, album name, year, etc., except some simple music description information such as privacy, copyright and original, which are very necessary in MP3 applications.
In 1996, in the “Studio 3” project, FricKemp proposed to add description information for storing songs at the end of the MP3 file and formed the ID3 standard. Until now, ID3 V1.0, V1.1, V2 .0, V2, .3 and V2.4 standards have been formulated. The higher the version, the richer and more detailed the relevant information is recorded.
The ID3 V1.0 standard is not complete and the information stored is too small to store lyrics, album covers, images, etc. V2.0 is a fairly complete standard, but it brings difficulties in writing software, although there are many people in favor of this format, very few are actually implemented in software. The vast majority of MP3s still use the ID3 V1.0 standard. This standard uses the last 128 bytes at the end of the MP3 file to store ID3 information. See Table 3 for instructions on using these 128 bytes.
Table 3 Final ID3 V1.0 File Description
length in
byte (byte) Description
1-3 3 Stores the “TAG” character, which indicates the ID3 V1.0 standard, followed by the song information.
4-33 30 Song name
34-63 30 Author
64-93 30 Album name
94-97 4 Year
98-127 30 Notes
128 1 MP3 music category, a total of 147 types.
3.3 File example
Open a file called test.mp3 in VC++ with the following content:
000000 FF FB 52 8C 00 00 01 49 09 C5 05 24 60 00 2A C1
000010 19 40 A6 00 00 05 96 41 34 18 20 80 08 26 48 29
000020 83 04 00 01 61 41 40 50 04 00 C1 2 41 50 64
…
0000d0 Fe FF FB 52 80 01 EE 90 65 6E 02 30
0000E0 32 0C CD CD CD CD 46 16 41 89 B8 408 89 300 408
0000F0 33 B7 00 00 01 02 FF FF FF F4 E1 2F FF FF FF FF
……
0001A0 DF FF FF FF FB 52 8C 12 00 E 01 FE 90 58 6E 09 A0 02
000150 8513 B0 AC 45 F6 19 61 26 26
0001C0 05 AC B4 20 28 94 FF FF FF FF FF FF FF FF FF FF
…
001390 7F FF FF FF FD 4E 00 54 41 47 54 45 53 54 00 00
0013A0 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
001400
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
001410 00 00 00 00 00 00 4E
File length is 1416H (5.142K), frame header is: FF FB 52 8C, converted to binary:
11111111 11111011
01010010
10001100T
