----- Original Message ----- From: "Jon Burgess" jburgess@uklinux.net To: "Klaus Schmidinger's VDR" vdr@linuxtv.org Sent: Friday, September 02, 2005 8:47 PM Subject: Re: [vdr] Aspect Ratio problems
Mike Parker wrote:
Thanks for the Help Darren.
By squashed I mean that the TV is showing a 'full' picture which is not
in
the correct aspect ratio, no pillar boxing. When a 4:3 is being transmitted I have to switch my TV into 4:3 mode and
the
tv puts in its own blank sides and the picture is correct. Watched bbc3 Apprentice last night, it shows pillar-boxing and no change
is
necessary, but surely that is 16:9 in stream (I did not check) so it
should
look ok anyway.
I recorded that program, it was broadcast as 16:9 stream containing pillar-boxed 4:3 content. If you have a 16:9 TV then you are correct, it will look OK without VDR or the TV doing any kind of proceeing on the
video.
The problem is when a 4:3 stream is being sent and dbv is set to 16:9,
the
4:3 picture is sent to my tv in 16:9 format and the tv does not automatically switch.
I have a 4:3 TV and use a DXR3 card for my display so I can't be certain about the capabilities of the FF card, but here is what I can tell you about what I believe should happen.
A true 4:3 video stream obviously doesn't have the black borders to make it look right on a 16:9 TV so something needs to add them. I believe what is meant to happen is that the TV gets instructed to switch into the 4:3 mode in one of two ways:
- Signalling via SCART pin 8 which probably isn't applicable since even
if you use some s-video to scart conveter then this pin will not be driven by the FF card. (see this link for some information on SCART http://en.wikipedia.org/wiki/SCART )
- Widescreen Signalling (WSS), which is a special signal embedded in one
of the offscreen lines of the picture much like the old TeleText system. ( see http://en.wikipedia.org/wiki/Widescreen_signaling ). I think this can either be delivered inside the original video stream by the broadcaster or be inserted by the playback card (I'm not sure if the FF is in this category).
Is this a vdr / driver problem?
Sorry I can't help here. Other possibilities include the video stream not including the WSS signal or your TV perhaps not obeying the WSS. Occasionally broadcasters have even been known to flag 4:3 programs as 16:9 by mistake.
Jon
vdr mailing list vdr@linuxtv.org http://www.linuxtv.org/cgi-bin/mailman/listinfo/vdr
Hi Jon
Just like to say thank you for taking the time to reply about the Aspect Ratio problem with vdr/tv.
The TV is about 4 months old (42" LG plasma) so pretty upto date. If I watch an analog tranmsission the tv switches correctly, or inserts blanks down side etc.
I am using composite out of the FF card so pin 8 is not a viable solution.
So that leads us to WSS - which I assume the tv does support as it appears to switch correctly on analogue.
It seems to me that setting 16:9 or 4:3 in vdr setup sets the output at that and WSS does not occur. I assume vdr needs this info for handling OSD etc.
I have replied off list due to the 'noise' generated by quoting ;-)
Thanks once again - I will keep on investigating.
Mike