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Comment by gnarbarian | Hacker News Reader

most likely. that's how the pi foundation retains control to prevent cheap Chinese knock offs.

What does the DRM prevent, specifically? Any use of the camera ribbon cable interface by any non-licensed camera?

Edit edit: I still have no idea...see reply from 'mrbteveman below.

Old first edit (wrong): Apparently, yes. This comment[0](2019) explains it slightly more. Evidently the ribbon cable ("CSI interface") can be used by pretty much anything...as long as that thing is not a camera / doesn't need the usual on-board image processing.

Evidently this prevents anyone from coming out with pi-compatible cameras with different features, e.g. different resolutions/framerates/night vision/infrared/zoom/etc.

0: https://news.ycombinator.com/item?id=20261787

in my experience you're better off just going with a USB camera most of the time. it's a cleaner abstraction point and supports more hardware and operating systems.

> What does the DRM prevent, specifically? Any use of the camera ribbon cable interface by any non-licensed camera?

> Apparently, yes. This comment[0](2019) explains it slightly more. Evidently the ribbon cable ("CSI interface") can be used by pretty much anything...as long as that thing is not a camera / doesn't need the usual on-board image processing.

This isn't accurate, the only thing they do is limit specific sensors from being used unless there is a matching authentication chip on the module, because those specific sensors are the ones they have manufactured camera modules with.

So for example the Pi Camera v2 module uses an imx219 sensor from sony and an authentication chip that the Pi firmware can check to verify the module was actually made by the Raspberry Pi company.

If you buy a 3rd party imx219 camera module (which would not have that authentication chip), it will not work on the regular Pi boards (but it will work with the Pi compute module boards because they don't do the authentication chip verification).

There have been plenty of 3rd party camera modules with entirely different sensors that work on the Pi for years, though with quirks related to the closed source drivers, but the modern libcamera stack on the Pi is explicitly designed to enable 3rd party camera modules.

Really useful info, thanks. I've never heard of this.

It's really disappointing. I have wondered if there are any very-high-quality cameras you can connect to a Pi, but found none. I guess this is why.

there are but you connect them via USB

But then you have the data-rate limitation of USB... is it equal to or better than that of the camera interface on the Pi?

I have a Pi 4, but don't remember if it's USB 2 or 3.

it's 3

Thanks

I can't be specific but your answer seems correct based on my experience.

it also makes it more challenging (unintentionally?) when trying to use the camera on other OSs like Ubuntu core.

For a company that likes to pretend it's a champion of open source, it's not very open source though, is it?

Yes, we can forgive them if a vendor refuses to release specs or source (Broadcom, for example), but implementing their own DRM to prevent others from making compatible cameras seems hypocritical and needlessly anti-user.

Is there some legitimate, user-serving benefit to this move that isn't apparent?

the raspberry pi foundation wants to recoup the cost and profit from the time and money spent to develop the raspberry pi camera software stack

this benefits the user by nature of the stack existing.

on the other hand now that an ecosystem has sprung up around this it's arguable that the DRM scheme is only needed to bootstrap the community

Did THEY develop this stack, or did the open-source community?

probably both

They have no business locking it down and preventing people from implementing higher-quality cameras, which would only add value to the Pi camera-interface "stack" anyway. No matter how you slice it, it's anti-community and encourages someone to come along and undermine the entire platform... which would REALLY squander the investment made.

I get your point. the problem these days is if you develop a completely open product your design will be copied and your device will be undercut and often beaten to the market by Chinese competitors.

How is the pi foundation supposed to make money in order to continue manufacturing and designing computers if they are unable to make any money? donations?

They're obviously selling computers as fast as they can make them. Locking down an interface on said computers doesn't seem to be protecting their core business; it seems to limit the usefulness of their core business. And make no mistake: I want them to survive and continue to churn out very cool products.

I just want a really high-quality (even if "only HD") camera, which would cost much more than what the Pi Foundation is targeting. I don't think it would cannibalize sales from anything they're trying to put out.

The Arduino ecosystem seems to have survived being truly open, hasn't it?

Reply on news.ycombinator.com