- display or set the UserComment tag contained in a JPEG Exif
] [ -w comment
] [ -s
] file ...
When invoked without arguments, the exifcom
utility displays the contents
of the Exif UserComment tag contained in file
to the standard output.
Otherwise, depending on the options specified, exifcom
will blank the
tag or set it to comment
Some digital cameras include a standard UserComment tag in the Exif data added
to the image files they produce. This comment tag is fixed-length and supports
multi-byte character sets (though exifcom
does not). Note that not all
cameras will include the tag.
The utility is conservative in its approach to writing the UserComment tag. It
does not modify, extend, or otherwise adulterate an image's Exif metadata
structure. When writing the tag it merely changes pre-allocated bytes.
is at the mercy of the Exif data creator for both
the presence of the tag and its length. It cannot create a UserComment tag
when the camera does not include one, nor can it write a comment longer than
the space pre-allocated by the camera. exifcom
only displays and writes
ASCII character set comments.
- Blank the UserComment tag, overwriting both the character
code and comment fields with NUL. The character code specifies how the
comment is represented; it is "undefined" when blank. This is
the state to which many cameras initialize the tag. When used in
conjunction with the -w option, exifcom will blank the
comment prior to setting it to comment.
- Overwrite or blank existing or unsupported comments without
prompting for confirmation.
- Write a prompt to standard error before overwriting or
blanking an existing or unsupported comment. If the response from the
standard input begins with 'y' or 'Y', the comment is overwritten. This
option is default behavior.
- Do not overwrite or blank existing or unsupported comments
and do not prompt for confirmation (i.e., automatically answer 'no' to a
confirmation prompt). This option takes precedence over both the -f
and -i options.
- Separate field name and value in the verbose and multiple
file cases with the string delim. The default is ': '.
- Be verbose when printing the contents of the UserComment
tag. Besides the comment itself (if present and supported), exifcom
will display the maximum comment length supported, the character code of
the comment, and the length of the comment.
- Set UserComment to the ASCII string comment. If
comment is longer than what the tag supports, it will be truncated
utility exits 0 on success. When displaying a comment from a
single file, if the UserComment tag is missing, it exits 1; if blank, it exits
2; if in an unsupported character code, it exits 3. Otherwise, it exits 1 if
an error occurs.
utility was developed using the January 2002 Exif standard,
version 2.2 (http://tsc.jeita.or.jp/).
If the tag doesn't exist or is too short, too bad.
utility and this man page were written by Eric M. Johnston