Re: [mediacapture-image] Add pan and tilt constraints

> @dsanders11 Thanks for info, those links basically prove that pan and tilt is a niche segment. I checked links for integrated cameras, looks like laptop manufacturers just soldered 3rd party components and took drivers that report pan/tilt capability.

Again, I disagree with this assessment. I don't see any evidence that they're misreporting having a pan and tilt functionality which they don't have. Look through the information in those links again, no two of them are reporting having the exact same set of controls, they're all slightly different. This isn't a case of generic drivers misreporting features.

> I doubt cameras installed in a window would be able to pan and tilt properly.

I think this is the root of different understandings. I believe when you hear pan and tilt you're imagining *mechanical* pan and tilt, with motors, of the source you mentioned in your description of accessories: "motorized heads, 3-axis gimbals, conference webcam or security IP cams chassis."

This is not the only way that cameras can provide the pan tilt functionality. Many of these cameras reporting pan and tilt have it as a feature of the CMOS chip used, like [this one here](http://www.onsemi.com/pub/Collateral/MT9M131-D.PDF). The datasheet for that CMOS chip (which is a tiny 4.6mm x 3.7mm) lists `"Electronic Pan, Tilt, and Zoom"` as a feature of the chip. Cameras using chips with *electronic* pan and tilt don't need anything mechanical inside their housing and simply have a lens over the CMOS chip. Their range of pan and tilt is much smaller, for example, 10 degrees in any direction, but it exists.

[Here on the Logitech site they cover controls for their C920 camera](http://support.logitech.com/en_us/article/Customize-HD-Pro-Webcam-C920-Settings-with-Logitech-Gaming-Software?product=a0qi00000069uigAAA). Of particular interest are these two bullets:

> * **Pan/Tilt controls** — Use the left, right, up, and down arrows to fine-tune the field of vision.
> * **Follow my face** — Click on the checkbox to allow the camera lens to automatically pan and tilt in order to follow your face.

[This is what a teardown of that webcam looks like](https://lieksa.pp.fi/oh7fes/cameras/focus.htm). There's nothing mechanical in there, the pan and tilt are being provided electronically.

Notice that the Logitech software has one of the features I was mentioning adding these controls to the spec would allow web developers to write - using the pan and tilt controls for face tracking.

I'll gladly concede the arc-degrees versus degrees in deference of other specs using degrees and if that's what others want. I will not, however, concede that pan and tilt are too niche to be in the spec.

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Received on Saturday, 17 June 2017 02:22:53 UTC