Auto-anamorpic zoom for letterboxed shows

[nielm]

(not sure this is the correct forum)

Does anyone know if there is a way of doing automatic zooming for letterboxes shows?

All my TV is broadcast 4x3, showing either 4x3 shows, or 16x9 letterboxed shows (and sometimes a wierd show that is half way between!)

I have a widescreen TV, and it can automatically detect 16x9 letterboxed shows and zoom in, removing the top/bottom black bars to make the 16x9 part fill the screen.

The problem with this is that in Sage, it hides the OSD.
Somtimes the TV sees the OSD and zooms out (but sometimes it stays like this) and sometimes it forgets and gets stuck in 16x9 zoomed mode.

I would like to run Sage in full 16x9 anamorphic so that the Sage UI always fills the screen. This currently means that I have to switch ARs for shows that are 16x9 (so that Sage zooms them to 150% vertically to fit the screen), and for 4x3 (so that Sage shrinks them horizontally to get left-right black bars).

What I am looking for is some kind of video post processor that can detect top-bottom black bars and perfom this zoom automatically (like my TV does).

I know black bar detection is possible (autoGK and Mplayer does it), and that zooming in post-processors is possible (ffdshow/presets), so I am looking for some way of linking the two...

Any ideas?

(PS for those who don't know, Anamorphic is where the pixels are not square, and the TV needs to stretch the image to get the correct aspect ratio, otherwise people look too thin (google define:anamorphic))

[Lucas]

I had a similar thought and came to nothing.

This could be implemented in the STV possibly by allowing custom ARs for each of the 16x9, 4x3, Fill, Source selections.

By reading the manual initially I thought that Sage TV would remember a different AR setting for each of the selections. In practice though, it didn´t stick.

So if we were allowed to add customised AR presets then that would be a semi-automatic way of doing it.

How does that sound?

[blade]

Originally Posted by Lucas

I had a similar thought and came to nothing.

This could be implemented in the STV possibly by allowing custom ARs for each of the 16x9, 4x3, Fill, Source selections.

By reading the manual initially I thought that Sage TV would remember a different AR setting for each of the selections. In practice though, it didn´t stick.

So if we were allowed to add customised AR presets then that would be a semi-automatic way of doing it.

How does that sound?

Sage already does this. If your's didn't stick then you have a problem somewhere.

[nielm]

Lucas:
I currently have
16x9 AR set with 100% horizontal zoom and 133% vertical zoom (giving 16x9 anamorphic)
4x3 AR set with 75% horizontal zoom and 100% vertical zoom. (giving 4x3 anamorphic with left/right black bars)
Fill AR is set with 100%/100%

When I can be bothered, I set my TV to 16x9 input and switch between the aspect ratio modes for:
16x9 letterboxed TV shows in 4x3 (16x9)
4x3 TV shows (4x3)
16x9 anamorphic DVDs (Fill), or 16x9 AVIs (Fill)
But more often, I just leave the TV on auto-zoom and set the Sage AR to Source.

(What you do is, in detailed setup/multimedia select the aspect ratio mode, then change the aspect ratio settings. The Zoom/position settings are saved for each mode.)

[Kanati]

I'm sure you could buy a processor to do this but you are probably looking at something like a 3000 dollar faroudja to do it... But if you find something significantly cheaper, let me know. I might be interested in one myself.

[nielm]

I suppose an alternative would be an off-line thingy (like SA, possibly using mplayer) that examines each file creating on-disk metadata indicating the size of the black bar region, then some Sage plugin (or girder) that can set the AR (or ffdshow preset) depending on which file is playing... but then this can be messed up by having commercials, other programes included which have a different AR.

Just can't help thinking that FFDSHOW with some Dscaler filter plugin should be able to do it dynamically

[stanger89]

Originally Posted by nielm

I suppose an alternative would be an off-line thingy (like SA,

I've asked Jere to add a flag to SA's output to mark if a show is letterbox or not. IIRC SA already detects AR and uses it in commercial detection.

[newmedia42]

I wish there was a way to just choose which aspect ratio you wanted to use with which show - for instance, Deadwood is always letterboxed, so use the 16x9 aspect radio setting. The Simpsons is not, so use Source or whatever... It seems like this would be a much simplier solution than trying to determine things algorithmically (shows with subtitles would probably be a nightmare, when the subtitles were in the black region).

[blade]

Aspect ratios based on favorites would be ok, but not all shows have every episode in the same format. For example the older episodes of SG1 are not letterboxed where as the newer ones are.

Many of us already run SA and those who don't should be. It's much faster than comskip and more accurate from my experice and if it can also give you the aspect ratio that would be another great benefit.

I'll be thrilled if Jere includes the aspect ratio along with the SA results and someone develops an import to take advantage of it.

[Lucas]

I was sure I understood the manual correctly........
Mine don't stick.... have to persist a bit more..... could be a cayars stv issue...

But I agree aspect ratio memory per favourite would be one step closer...

[KrisAcker]

PAL (and maybe other) widescreen TV’s can be switched between 4/3, 16/9 letterbox and 16/9 anamorphic from hidden information called "Wide Screen Signaling" (WSS). This information resides in the invisible lines of the picture, just as teletext does. Even with playback of a VHS tape, the TV is able to switch to the correct format. There must be a way to extract that information from the Sage recordings.

If you could then link each of those signals to a particular AR in Sage, we would not have to switch AR's manually. For those occasions when a 16/9 letterbox is broadcast without WSS, a black bar detection system would be still be required.

[nielm]

unfortunatly, I believe that info is lost in the capture/encoding process...
http://en.wikipedia.org/wiki/Widescreen_signaling

[Kanati]

I dunno... there's definitely a data stream at the top of most sage recordings... If we just knew how to read it.