Digital Keystone for Cheap/low-cost Projectors

charles_carmichael · May 7, 2023 at 7:38 AM

I have a cheap 1080p projector, mounted in almost the perfect position. the ceiling mount that I had on hand was a tad short and incidentally had to tilt the projector down.

Tilting made the image go into a 'trapezoid'. Now, yes, this projector has the arbitrary "keystone", but that uses a plastic fresnel lens and blurs out the top and bottom of the image except for a tiny horizontal area in the middle.

I've been googling and came across a couple of projects, namely

1. mpc-hc (1.7.10.252) + ffdshow (both projects shutdown)

2. Multi-Point Keystone Video Player (made only for Mac, but the creator says the library can be compiled for Windows as well. Not even sure what would be involved to do it by myself)

Seeing as both the projects mentioned above do have the source code available as open source, would it be possible to include a feature built-in to Kodi for this?

I have like 5 or 10 degrees of tilt to correct, and I'm fine with a little compression (literally bootstrapped a 7.1 ht setup under $250, so I'm fine with compromises) (setup: $100 projector, $60 5.1 with ac3-in modded to 7.1, $40 7.1 HDMI audio extractor, $50 misc.)

**chewitt** · May 7, 2023 at 11:48 AM

Quote from charles_carmichael

Seeing as both the projects mentioned above do have the source code available as open source, would it be possible to include a feature built-in to Kodi for this?

Kodi is open-source to technically everything is always possible, but since most projectors have in-built keystone correction capabilities adding a software correction feature is a niche use-case; and the perpetual challenge with niche use-cases and open-source is finding that one other person with the coding skills and motivation to implement and then maintain support for the feature.

It's not something LE would do .. in part because it would need to be done in Kodi; we only package Kodi into a convenient distro image.

charles_carmichael · May 7, 2023 at 3:50 PM

i posted on kodi subreddit and the mods just deleted my post saying and I quote "talk to the manufacturer"

If I had that kind of industrial influence or the budget for the proper equipment, I would be using and an AVR, not bootstrapping everything from forums.

I understand that keystone will be niche, but, wasn't kodi, and by proxy LE once a niche? giving power to DIY'ers? (born out of necessity for ht enthusiasts on a budget)

in any case, thanks for replying, which is much more than wht I can say for team-kodi who wasn't even open for public discussion

**chewitt** · May 7, 2023 at 4:11 PM Best Answer

Kodi hasn't been niche for 20 years and while LE is smaller, we've always sought to keep the distro simple and one of the ways that's done it avoiding niche things that few people use. To quote Spock .. "the needs of the many outweigh the needs of the few"

I wouldn't guarantee that the subreddit has official team members moderating it. Kodi forums are the correct place to make and discuss feature requests but you'll need to find someone who cares to code the feature.

charles_carmichael · May 7, 2023 at 4:53 PM

Quote from charles_carmichael

"talk to the manufacturer"

😞 i give up