Do we need a powerNetworkFrequency constraint?

Most cameras seem to have some place in their API where you set the line
power frequency of the area you live in; this is used to suppress
flicker from fluorescent or LED-based lighting fixtures.

Many times, the OS or the browser can make a guess at the right power
frequency based on environment factors like timezone or location, and
everything's OK.

But sometimes it's wrong. And it makes people unhappy.

One option is to have a way to override the setting from the application
if needed; we can, for instance, have a tri-state constraint, mirroring
the camera APIs:

powerNetworkFrequency = "50Hz", "60Hz", "default"

(I don't see a case for allowing "powerNetworkFrequency=200", which
would be the case if we made it a number.... even though there are
railway power grids at 16 2/3 Hz, they're rare enough that we should
ignore them for simplicity's case).

What do people think?

(Also filed as https://github.com/w3c/mediacapture-main/issues/234)

Harald

-- 
Surveillance is pervasive. Go Dark.

Received on Tuesday, 25 August 2015 05:47:42 UTC