[MPlayer-users] Slave mode: set_property time_pos syntax?

[Phil Rhodes]

Hi,

I'm in the process of writing what you can consider to be a frontend for 
mplayer, using it in slave mode. Actually it's a bit more than that, since 
it does MIDI and RS232 device control as well, but for the sake of this 
discussion it's probably safe to treat it as a straightforward slave-mode 
frontend. OS is XP Pro and I am using the MPlayer Sherpya-SVN-r23169-4.1.2 
binaries. Control is via windows scripting host, with the mplayer process 
created using WScript.Shell::Exec(). I'm sending and receiving via the 
returned Process object's StdIn and StdOut methods. My commandline looks 
like this:

 c:/mplayer/mplayer.exe -slave -idle -osdlevel 0 -colorkey 000000 -adapter 
2 -fixed-vo -vf eq -channels 6 -af 
pan=4:1:0:0:0:0:1:0:0:0:0:0:0.5:0:0:0:0.5:0:0:1:0:0.2:0.2:0.2:0.2


As part of my use of slave commands, most of which work fine, I'm attempting 
to give my users the option to skip part of the file by sending a 
"set_property time_position x" command to mplayer just after I "load 
filename.avi". Although I'm sending a lot of get_time_position updates at 
the time, all of which work fine, when I send the set_property command, 
absolutely nothing appears to happen. Here's a snippet of logging produced 
by my frontend, where "sent" is what I'm sending to mplayer, and "read" is 
what I'm getting back:

Fri Jul 27 13:03:57 UTC+0100 2007 : Sent: get_time_pos
Fri Jul 27 13:03:57 UTC+0100 2007 : Read: ANS_TIME_POSITION=6.1
Fri Jul 27 13:03:58 UTC+0100 2007 : Sent: set_property time_pos 30
Fri Jul 27 13:03:58 UTC+0100 2007 : Sent: get_time_pos
Fri Jul 27 13:03:58 UTC+0100 2007 : Read: ANS_TIME_POSITION=6.3

...no joy. I'd expect to see the reported time position leap to 30 (and the 
playback as well, of course). I suspected that this might be due to my using 
compressed files with large gaps between keyframes, on the assumption that 
mplayer might not be able to seek to a keyframe that's nearer thirty seconds 
than I am already. So, I tried it with an uncompressed AVI, every frame 
therefore being a keyframe, but the behaviour didn't change.

Am I using incorrect syntax or something? I've put the full log of 
everything I sent and received here: 
www.1159productions.com/test182/session.log

Any pointers gratefully received.

Phil