gnus: X-Face
9.14.1 X-Face
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‘X-Face’ headers describe a 48x48 pixel black-and-white (1 bit depth)
image that’s supposed to represent the author of the message. It seems
to be supported by an ever-growing number of mail and news readers.
Viewing an ‘X-Face’ header either requires an Emacs that has
‘compface’ support (which most XEmacs versions have), or that you have
suitable conversion or display programs installed. If your Emacs has
image support the default action is to display the face before the
‘From’ header. If there’s no native ‘X-Face’ support, Gnus will try to
convert the ‘X-Face’ header using external programs from the ‘pbmplus’
package and friends, see below. For XEmacs it’s faster if XEmacs has
been compiled with ‘X-Face’ support. The default action under Emacs
without image support is to fork off the ‘display’ program.
On a GNU/Linux system, the ‘display’ program is included in the
ImageMagick package. For external conversion programs look for packages
with names like ‘netpbm’, ‘libgr-progs’ and ‘compface’. On Windows, you
may use the packages ‘netpbm’ and ‘compface’ from
<http://gnuwin32.sourceforge.net>. You need to add the ‘bin’ directory
to your ‘PATH’ environment variable.
The variable ‘gnus-article-x-face-command’ controls which programs
are used to display the ‘X-Face’ header. If this variable is a string,
this string will be executed in a sub-shell. If it is a function, this
function will be called with the face as the argument. If
‘gnus-article-x-face-too-ugly’ (which is a regexp) matches the ‘From’
header, the face will not be shown.
(Note: ‘x-face’ is used in the variable/function names, not ‘xface’).
Face and variable:
‘gnus-x-face’
Face to show X-Face. The colors from this face are used as the
foreground and background colors of the displayed X-Faces. The
default colors are black and white.
‘gnus-face-properties-alist’
Alist of image types and properties applied to Face (Face)
and X-Face images. The default value is ‘((pbm . (:face
gnus-x-face)) (png . nil))’ for Emacs or ‘((xface . (:face
gnus-x-face)))’ for XEmacs. Here are examples:
;; Specify the altitude of Face and X-Face images in the From header.
(setq gnus-face-properties-alist
'((pbm . (:face gnus-x-face :ascent 80))
(png . (:ascent 80))))
;; Show Face and X-Face images as pressed buttons.
(setq gnus-face-properties-alist
'((pbm . (:face gnus-x-face :relief -2))
(png . (:relief -2))))
Image Descriptors (elisp)Image Descriptors. for the valid
properties for various image types. Currently, ‘pbm’ is used for
X-Face images and ‘png’ is used for Face images in Emacs. Only the
‘:face’ property is effective on the ‘xface’ image type in XEmacs
if it is built with the ‘libcompface’ library.
If you use posting styles, you can use an ‘x-face-file’ entry in
‘gnus-posting-styles’, Posting Styles. If you don’t, Gnus
provides a few convenience functions and variables to allow easier
insertion of X-Face headers in outgoing messages. You also need the
above mentioned ImageMagick, netpbm or other image conversion packages
(depending the values of the variables below) for these functions.
‘gnus-random-x-face’ goes through all the ‘pbm’ files in
‘gnus-x-face-directory’ and picks one at random, and then converts it to
the X-Face format by using the ‘gnus-convert-pbm-to-x-face-command’
shell command. The ‘pbm’ files should be 48x48 pixels big. It returns
the X-Face header data as a string.
‘gnus-insert-random-x-face-header’ calls ‘gnus-random-x-face’ and
inserts a ‘X-Face’ header with the randomly generated data.
‘gnus-x-face-from-file’ takes a GIF file as the parameter, and then
converts the file to X-Face format by using the
‘gnus-convert-image-to-x-face-command’ shell command.
Here’s how you would typically use the first function. Put something
like the following in your ‘~/.gnus.el’ file:
(setq message-required-news-headers
(nconc message-required-news-headers
(list '(X-Face . gnus-random-x-face))))
Using the last function would be something like this:
(setq message-required-news-headers
(nconc message-required-news-headers
(list '(X-Face . (lambda ()
(gnus-x-face-from-file
"~/My-face.gif"))))))