[vdr] OSD and subtitles trouble

Marko Mäkelä marko.makela at iki.fi
Sat Nov 9 12:59:51 CET 2013

On Sat, Nov 09, 2013 at 11:36:55AM +0100, Klaus Schmidinger wrote:
>I just tried this on my VDR with a TT S2-6400 and there was no such 
>problem. I assume that this is related to the softdevice OSD 
>implementation and not the core VDR.

Thank you for testing, Klaus!

Were you able to test the other problem (the OSD menu becomes fully 
transparent and then normal again when subtitles would want to update 
the OSD)? I can provide a short recording if needed. I guess that these 
bitmap-based subtitles are not too widespread functionality. Even here 
in Finland, only the state-owned YLE is using them; the commercial 
broadcasters are burning the subtitles into the video layer.

In any case, these are very minor problems now; I have an acceptable 
workaround for both. I just thought that I would go the last mile and 
polish a bit more, to prepare for a proper release of softdevice.

While I now understand the VDR and softdevice OSD implementation a 
little better, I still do not fully understand it. Currently, it is a 
bit of a mystery for me what happens when the OSD is closed and the 
screen is cleared. In osd.c I understood that there could be a 
transparent "background pixmap" whose relevant part would be invalidated 
when upper-layer pixmaps or bitmaps get removed. But, will this also 
happen when the whole OSD is closed, or only for closing individual 

Based on the SoftOsd.c debug output and some gdb sessions, it seems to 
me that the cSoftOsd object gets created and destroyed repeatedly, maybe 
every time something is displayed and then hidden again. Is this the 
correct object life cycle? Is there some wiki page or other 
documentation than the source code?

Best regards and thank you for the great work,


More information about the vdr mailing list