NAME
mozplugger - a streaming multimedia plugin for UNIX mozilla
DESCRIPTION
MozPlugger is a Mozilla plugin which can show many types of multimedia
inside your Mozilla. To accomplish this, MozPlugger uses external
programs such as mplayer, xanim, mtv, timidity and tracker.
CONFIGURE FILE
You can configure mozplugger by changing the file mozpluggerrc which
can be located in any of the following directories:
$MOZPLUGGER_HOME/
$HOME/.mozplugger/
$HOME/.netscape/
$HOME/.mozilla/
$HOME/.opera/
$MOZILLA_HOME/
$OPERA_HOME/
/usr/local/netscape/
/etc/
/usr/local/mozilla/
/usr/local/netscape/
MozPlugger will use the first mozpluggerrc it finds and ignore any
others. The search order is from top of the list above.
The format of mozpluggerrc is very simple. The general layout is to
have one or more lines describing mime types followed by one or more
lines describing commands used to handle those mime types. Lines
beginning with # are considered comments and are ignored. Here is a
simple example:
video/mpeg: mpeg: Mpeg video
video/quicktime: qt,mov: Mpeg video
: xanim +W$window -Zr +q +Ze +f $file
Each line describing a mime type has three fields:
mime type : extensions : description
mime type
The mime type is the standardized name for the content type you
want MozPlugger to handle. This must be the same type as the web
server claims the file to be, or MozPlugger will not be used for
that file, regardless of the extension. Note: Some web servers
incorrectly report the wrong mime type, blame the web server
adminstrator not mozplugger.
extensions
This is a comma separated list of extensions that should be
associated with this particular mime type. The extensions are
only used when a web server does not report what type of file it
is, or when loading files directly from disk.
description
This is the description that shows up in about:plugins and in
the application preferences section in Mozilla.
Lines that describe what command to use for a mime type must begin
with a whitespace and have two fields:
flags : command
flags This is a space separated list of flags associated with the
command and tells mozplugger how to handle this command. See
below for further details.
command
This is a command which is sent to /bin/sh when handling this
mime type. Mozplugger assumes the command line starts with the
name of an application followed by various arguments passed to
that application.
USING M4
When loading, MozPlugger will pass the mozpluggerrc file through m4, a
general purpose macro processor (assuming m4 is installed). This
provides the ablity to use macros within mozpluggerrc especially for
those commonly used command lines. m4 brings text replacement,
parameter substitution, file inclusion, string manipulation,
conditional evaluation, arthemtic expressions, etc to mozpluggerrc.
Please see m4 documentation for more details.
FINDING THE RIGHT COMMAND
When MozPlugger is called from your browser, it looks through the
configuration file and finds a matching mime type.
When a matching mimetype is found, it tries to figure out which command
to use. Commands that have the flags loop, embed, noembed, link and
fmatch will be rejected if they do not match what is expected from the
associated HTML code (see later for details).
In addition for a command to be chosen the application has to be
available. That is, MozPlugger will assume the first word of the
command is the name of an application and search $PATH for that
application. If that application is not found MozPlugger will skip that
command line.
Of the commands that remain, Mozplugger looks for the first command
that has the stream flag set. If there is not such a command line,
Mozplugger then downloads the file and picks the first (of the
remaining) commands.
WORKING WITH JAVA SCRIPT
Mozplugger supports a JavaScript interface that allows the state of the
embedded object (i.e. mozplugger) to be queried from JavaScript.
Currently mozplugger supports the following properties.
isPlaying
This property has the value true if the application that
mozplugger launched to handle the embedded object is running and
false if either no application was launched or that application
has now terminated.
WHEN IT DOESNT WORK
If for some reason the embedded object fails to be rendered in the
browser, this could be a fault with the application as opposed to
MozPlugger. To diagnosis the fault it is suggested that first you make
sure that any output from the application will be visible to you by
removing the noisy flag (if set in mozpluggerrc).
Next run the browser from the shell (xterm or equivalent) passing the
appropriate browser command line flag to enable output from stdout and
stderr to be displayed.
For example, for firefox the command line string is:
firefox -debug
This should allow any output from the application to be visible at the
shell and hopefully lead to a diagnosis of the fault.
FLAGS
autostart
This flag indicates that the command uses the $autostart
environment variable. That is mozplugger will run the command on
the assumption that the command/application will check the value
of the $autostart environment variable. If this flag is not
present and the HTML code for the embedded object indicates
autostart is false, mozplugger will not run the command but
instead draw a single start button.
repeat This flag indicates that the command uses the $repeats
environment variable. That is mozplugger will run the command on
the assumption that the command/application will check the value
of the $repeats environment variable and perform the repeats. If
this flag is not set, mozplugger will perform the required
number of repeats as indicated in the HTML code by calling the
command $repeats times.
loop This indicates that the command loops forever. If the HTML code
for the embedded object indicates don't loop/repeat forever
(e.g. the loop attribute is not present or not set to true), the
command on this line will not be used.
stream This indicates that this command can take an url. In this case,
the environment variable $file contains the URL of the file to
play and the browser does not download it. It is assumed that
the command can handle the URL. Note: if a username and
password is required for this URL, the command/application will
have to obtain this as it is not passed to it from the browser.
ignore_errors
This flag tells MozPlugger to ignore the exit status of the
command. For example is mozplugger is repeating the command 'n'
times and the command exits with an error, normally mozplugger
would terminate at this time. With this flag set, mozplugger
continues the repeats.
noisy This flag tells MozPlugger to redirect the stdout and stderr of
the command to /dev/null.
swallow (name)
This flag tells mozplugger that the command will open a window
with the specified name and that Mozplugger will then move this
window inside your browser. If name is prefixed with '=' then
mozplugger looks for an exact match with the window name, if the
prefix is '~' then mozplugger looks for a case insensitive
match, if prefixed with '*' then mozplugger looks for a window
name that starts with 'name' and is case insensitive. If none of
these prefixes then, mozplugger checks if name occurs anywhere
in the window name, but is case sensitive. Note any spaces
between the brackets are counted as part of the window name.
The window name to use in mozpluggerrc can be obtained by using
the utility xprop(). Run the command in question, type "xprop
WM_CLASS" at a shell prompt and then click on the application
window. In addition any occurance of %f in the name is replaced
with the filename being loaded (without path), %p is replaced
with the full filename including path.
fmatch (string)
This flag defines a command that will be used only if the
filename or url (i.e. $file) contains 'string'. If 'string' is
prefixed with '*' then mozplugger defines a match when the file
starts with 'string' (the check is case insensitive). If
'string' is prefixed with '%' then mozplugger defines a match
when the file ends with 'string' (the check is case insenstive
and ignores any parameters at the end of a url {i.e.
'?xxx=yyy'}). If none of these prefixes then mozplugger defines
a match when the 'string' is found somewhere in the file (but
this time match is case sensitive). Note any spaces between the
brackets are counted as part of the 'string'.
nokill This flag tells MozPlugger to not try to kill the command when
leaving the page, and to not start the command in a loop. This
is normally used for applications that are not swallowed and can
play multiple files, such as xmms.
exits This flag tells MozPlugger that the command will exits straight
away and hence does not need to be killed when leaving the page,
and to not start the command in a loop. This is normally used
for applications that just display an image in the $window and
then exit.
fill This flag tells MozPlugger to maximize a swallowed window.
maxaspect
This flag tells Mozplugger to maximize a swallowed window while
keeping the width/height ratio constant.
controls
This flag tells MozPlugger to draw controls and is typically
used with audio files to display a controller with the buttons
play, pause and stop. Be aware if the embedded object has no
sub-window defined within the browser's window (e.g. if the HTML
uses the tag hidden = true) then the controls will not appear.
embed This flags tells Mozplugger to only use this command if the
associated HTML refers to an embedded object that is a small
part of a HTML page.
noembed
This flags tells Mozplugger to only use this command if the
associated HTML refers to a separate window that only contains
the object.
links This flag tells Mozplugger to only use this command for embedded
objects that are really links to external applications (such
objects typically use the target and href variables to indicate
a clickable link). Embedded Quicktime objects sometimes use this
mechanism.
needs_xembed
Some applications when embedded requires the Xembed protocol,
other applications don't want the Xembed protocol. Add or remove
this flag if you find that you cannot move keyboard focus to the
embedded window. Currently it appears QT4 based applications
require this flag.
ENVIRONMENT VARIABLES
There are some envirnoment variables that control the behaviour of
Mozplugger.
MOZPLUGGER_HOME
If MOZPLUGGER_HOME is defined, the folder $MOZPLUGGER_HOME is
checked for the configuration file mozpluggerrc
MOZPLUGGER_TMP
If MOZPLUGGER_TMP is defined, then any temporary files are
placed in $MOZPLUGGER_TMP.
TMPDIR If MOZPLUGGER_TMP is not defined, but TMPDIR is defined, then
any temporary files are placed in $TMPDIR/mozplugger-xxx/ where
xxx = PID.
PATH Mozplugger uses PATH to look for executables
MozPlugger gives some variables to /bin/sh when running the command,
these variables are:
$autostart
This variable contains 1 or 0. When set to 1 it indicates that
the command should start playing/showing the associated media.
By default it is 0 if controls flag is present and 1 otherwise,
but it is overridden if the associated HTML contains the
attribute autostart or autoplay. Command/applications that use
this environment variable should also have the autostart flag
set.
$repeats
This variable contains how many times the file should be played.
By default it is once, but it is overridden if the associated
HTML contains the attribute loop, numloop or playcount.
Command/applications which use this environment variable should
also have the repeat flag set.
$window
This is the X window Mozilla has given the plugin. This can be
used with applications such as MPlayer to display graphics
inside the mozilla window. Be aware if the embedded object has
no sub-window defined within the browser's window (e.g. if the
HTML uses the tag hidden = true) then the variable will have the
value zero (null).
$hexwindow
Same as $window except the value is expressed as an hexidecimal
string in the form 0xNNNNNN where NNNNNN is the hexadecimal
digits.
$width This is the horizontal resolution in pixels and is taken from
the width attribute in the HTML code.
$height
This is the vertical resolution in pixels and is taken from the
height attribute in the HTML code.
$file This is the file to play. If the command has the stream flag
set, this variable contains the URL of the file to play. This is
taken from the associated HTML code. The value is that of the
attribute src, data, href, qtsrc, filename, url or location
depending on which is present and whether the <EMBED> or
<OBJECT> tag is used. If the stream is not set, this variable
contains a local temporary file that the browser has created.
$fragment
This is the part of the original URL that appears after the # if
it exists. Sometimes this contains additional information that
could be useful for the application e.g. starting page number in
a pdf document
$mimetype
This variable contains the mime type of $file.
$VAR_<parameter_name>
All the parameters of the <EMBED> or <OBJECT> tags are made
available in mozpluggerrc through environment variables. For
example the parameter loop="1" in an <EMBED> tag defines the
variable VAR_loop=1.
BUGS
You have to remove ~/.netscape/plugin-list or
~/.mozilla/firefox/pluginreg.dat after changing the configuration, or
nothing will happen. This is a Netscape/Mozilla/Firefox bug, not a
MozPlugger bug.
Netscape 3.x will not play anything for <EMBED> tags for which height
or width are zero. This too is a Netscape bug.
Occassionally you may notice some zombie mozplugger-helper processes
(defunct), this is not a bug, this is by design. The zombie processes
occur when either the application exits or when using nokill flag
(without exiting the page with the embedded object). The zombie(s) are
reaped when closing the web page containing the associated embedded
objects.
If using behind a non-transparent HTTP proxy, it may be found that the
commands using the stream flag do not work. This is because the proxy
settings are not passed to the application in the command line. To work
around this situation, don't use the stream flag OR edit the
mozpluggerrc file and passed in necessary proxy setiings via the
command line.
It has been found that certain combinations of browser and embedded
application don't allow keyboard focus in the embedded application, if
this happens to you try adding or removing the "needs_xembed" flag from
the associated command in mozpluggerrc.
AUTHORS
Fredrik Hubinette, hubbe@hubbe.net
Louis Bavoil, louis@bavoil.net
Peter Leese, peter@leese.net
2010 Aug 07 mozplugger(7)