HDMI to composite/S-Video conversion without lag?

[Jelster64]

I'm a speedrunner, and I have a lot of friends who stream on Twitch. When I talk to them about maximizing their footage quality for their stream, they almost always say: "I only care about making my stream look nice. I don't care how it looks on my CRT. Also, I want to minimize input lag as much as possible." So I've been wondering what options they have (for the Wii). The obvious step is S-Video, but it's obviously better to use 480p (over component or Wii2HDMI). The problem is that consumer CRTs don't support 480p, and most people still want to keep using their consumer CRTs to minimize input lag. Almost no one is willing to spend the money for a low-lag HD monitor or 480p-compatible PVM.

So the ideal setup for these people would be as follows: Wii2HDMI into an HDMI splitter. One HDMI cable goes into the HD capture card, the other one gets converted to composite or S-Video and goes into the CRT (without additional input lag).

My question is: is this possible? Is there a device that can convert HDMI to composite/S-Video without additional input lag? Alternatively, is there a device that can convert 480p component to composite/S-Video without additional input lag? I've seen this video by RetroRGB where he shows off the Extron Super Emotia, a downscaler that converts 480p VGA signals to 240p. Is there anything like that for HDMI/component sources?

[AndehX]

Why not just capture component? If you're playing it on a PVM in s-video or composite, then its going to be 480i/240p anyway, so you might as well just run component into your PVM and capture card.
480p looks no different to 480i through a capture card, once it's deinterlaced.

[Xer Xian]

I don't think there's any device that downscales from 480p without adding at least some latency (6-7ms is the bare minimum you can get). Of course, simple hdmi to ntsc/pal encoders with no downscaling are non-existent, since no CRT will accept high resolutions over s-video.

Your friends/you might consider getting a vga monitor, they're still easy to find pretty much everywhere and also very cheap. With one of these, the chain would be Wii2HDMI > hdmi splitter > (out 1: hdmi to vga + audio converter > vga monitor), (out2: capture device)
The splitter wouldn't be needed with an HDFury 3 or 4 since they have dual analog/digital output.

If getting a vga CRT isn't an option, then just move the processing on the video capture chain, where lag isn't an issue. For example: Wii 480i output > s-video/rgb/component splitter > (out 1: CRT), (out 2: capture device). If capture quality really matters, you should consider processing the signal with a good video processor before feeding the capture device.