[vdr] OSD and subtitles trouble

Klaus Schmidinger Klaus.Schmidinger at tvdr.de
Sat Nov 9 13:08:15 CET 2013


On 09.11.2013 12:59, Marko Mäkelä wrote:
> 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 have no such problem here. If I open the menu of the channel/progress display while
subtitles are active, no subtitles are displayed while the menu is open and they
continue to be displayed once the menu has been closed again.

>  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.

"burning the subtitles into the video layer" is probably the worst idea ever.
This totally deprives the viewer of the possibility to choose between different
language subtitles or turn them off altogether.
Almost all of the test samples I have here use proper DVB subtitle bitmaps.

> 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 "windows"?

When the whole OSD is closed, ther is nothing that gets displayed.

> 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?

Yes.

> Is there some wiki page or other documentation than the
> source code?

Not to my knowledge.

Klaus



More information about the vdr mailing list