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Revision as of 07:33, 7 February 2006 by Khlut (talk | contribs) (Back-end programs)
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Static tag parameters

decimation for accelerated DCT (0-3);
width of the object window;
the iteration of the playback (0 or nothing is infinitely);
frame frequency;

Dynamic variables (also it is possible to use they as the parameters of tags)

url of the file or stream;
as yet simply another name for href.
pause=1 or play=0
to pause player;
pause=0 or play=1
to continue playback;
to start player again if it was terminated (by error or end of file);
to terminate player;
to run mencoder instead of mplayer;
to always ask the name of file for recording;
not to ask if user sets it in dialog

Status variables

This the fact that outputs mplayer or mencoder. Now strings simply are splitted into two parts on the first of the symbols '=' or ':'. The left part becomes a name of the variable (gaps and nonlatin letters are removed) and the right part is a value.

the message of mplayer/mencoder about last frame;
last error message;

Others variables are possible but they are not used as yet.

special variable, the state of player process: 0 - not running, 1 - running;
pause, play
it is analogous - the pause state.

Callback functions

On the arrival of data from a player it is transferred to the variables of object and it become accessible from javascript. In this case if it is assigned the function with the corresponding name "on<variable_name>" will be called.

be called on starting and stopping of playing or recording processes;
on error message;
on each frame playing.
onmousedown and other standard callbacks
are given already by browser and do not need some code inside the plugin.

Back-end programs

Currently used:

  • mplayer (compiled with live555)
  • mencoder from mplayer package
  • ElphelOgm - for receiving pure multicast or unicast rtp with mjpeg video.

For ElphelOgm to be used, the mime-type must begin with video/m and the URL must be specifed as: rtp://ip:port/ , where:

ip -
the stream multicast ip
port -
the stream multicast port

For unicast destination i.e. client ip:port must be specifed and a stream server must be programmed to continuosly send stream to this address and port. Dynamic change of the URL is not yet supported for RTP. Instead this use the sequence:; obj.src=...;;