JEITA CP-3451
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[Information items and chunks]
ever
Records the version information (number) of this standard.
As with Exif image files, it is recorded in 4 bytes. The address bytes are recorded as A1, A2, B1, B2, starting with
the lowest number. A1 and A2 store the upper part of the standard version, with the lower part stored in B1 and B2.
A1, A2, B1 and B2 are ASCII numerals giving the version number, but NULL termination is unnecessary. This
chunk is mandatory.
On the conventions for version number updating, see section 5.2.
Ex.) "0200" (Note: =Version 2.00)
erel
Records information pointing to an Exif image file related to the Exif audio file recorded in this chunk. Recording
this information makes it possible for a camera or application software to map an image to sound during playback.
The relational information consists of the name of the corresponding Exif image file, given as an 8-character file
name plus 3-character extension in ASCII format. The path is not written. Stipulations on images are given in
section 4.6.5. File naming rules are covered in section 0.
The mapping of Exif image files and audio files is done in any of the three ways shown in Table 30. If multiple files
are mapped to one file as in [2] or [3] of Table 30, the above format is used to record just one destination file name.
If there are multiple destination files, the first recorded file is given.
In the case of [2] in Table 30, for the Exif audio file "SND00001.WAV" only "DSC00001.JPG" is given as the related
image file. When there are three Exif image files "DSC00001.JPG," "DSC00002.JPG" and "DSC00003.JPG," the
related Exif audio file name for each of them, "SND00001.WAV," is indicated. By combining multiple relational
information, a variety of playback possibilities can be supported. The method of using relational information is left to
the implementation on the playback side. Since this information is an ASCII character string, it is terminated by
NULL. If there is a related Exif image file, this chunk is mandatory.
Ex.) "DSC00001.JPG"Z
Table 30 Mapping between Image and Audio Files
Relationship
Exif Image File
Exif Audio File
[1]
1 to 1
DSC00001.JPG
SND00001.WAV
[2]
Many to 1
DSC00001.JPG
DSC00002.JPG
DSC00003.JPG
SND00001.WAV
[3]
1 to many
DSC00001.JPG
SND00001.WAV
SND00002.WAV
SND00003.WAV
etim
Records the time of Exif audio file creation. This is defined as the time the recording of audio data was started.
Time is expressed as a variable-length ASCII string. In order to conform as closely as possible to the Exif image file,