How do I write a Keystone correction filter for VLC?

How can I set up keystone correction in VLC? If this is not a supported feature, has anyone had any experience writing an add-on filter for VLC? If so, links/开发者_JAVA技巧examples would be very appreciated!

Thank you

The reason I came looking for this feature is because the way projectors apply the correction is to start throwing away pixels (and hence light). The way I would prefer to do it is by throwing away (ie masking/cropping) picture information. In fact in my particular circumstance, I wouldn't actually be throwing away anything of value, since my image is not as wide as my projector's chip. Provided the computational grunt was manageable, then I would vote for this as a worthwhile feature.

It's been a few years but VLC still doesn't have keystoning feature. I have, however, found 2 software keystoning solutions in Microsoft Windows:

Movies:

• Use MPC-HC Player
• Install ffdshow tryouts (http://ffdshow-tryout.sourceforge.net/)
• Enable ffdshow raw video filter
• Configure "perspective correction"

Entire desktop:

• Projection Mapper from NeuroRehabLab (http://download.cnet.com/Projection-Mapper/3000-20418_4-76027245.html)

This software is a tiny bit laggy, but still perfect for slideshows and other non-lag sensitive applications.