SageTV, FFDShow and non-linear stretching

[Lester Jacobs]

I'll be purchasing a flat panel TV within the next few months. However, at least initially, 90% of the material that I'll be watching will be 4:3 aspect ratio formatted whilst my flat panel will be 16:9 (or thereabouts). Additionally I'll be connecting to the flat panel via its VGA port and thus any aspect handling functionality built into the flat panel firmware itself will likely be circumvented (since the flat panel will "see" a 16:9 signal from my computer, it won't know that the video material is really 4:3).

However I don't want to end up having to watch 4:3 aspect ratio material recorded by SageTV with side bars. Nor do I want to watch the material grossly distorted by the typical "simple" stretching algorithm which makes everyone look short and fat (Sage's "fill" algorithm for example).

Ideally, I'd like to have a non-linear stretch capability. I understand that SageTV does not support this natively but I understand that it might be possible to achieve what I need using ffdshow.

Has anyone used ffdshow to achieve non-linear stretch in SageTV? If so, how?

Thanks
Lester

[lobosrul]

Hmm, you do realize pretty much everything (as far as digital TV goes) is scaled in one way or another? Most HDTV's are actualy 1366x768 so even 720p is scaled up a bit. Plus theres overscanning.

I use NVIDIA's purevideo decoder, which I guess handles scaling, only mp4's go thru ffdshow (in my setup). 4:3 actualy looks better running thru sage than off the cable box.

[blade]

I believe FFDshow can do nonlinear stretching, but it's going to require a good bit of cpu power. Also by doing this you won't be able to use any hardware acceleration your video card might offer.

The Nvidia cards and PureVideo decoder do an excellent job. If you have an Nvidia card you may find losing the PureVideo hardware features are not worth the trade off.

When I first started using Sage I watched all of my 4:3 material stretched, but now find any sort of stretching unacceptable. I watch everything as 4:3 except for letterboxed, which I zoom in with Sage to fill my 16x9 screen.