- From: Miguel Casas-Sanchez via GitHub <sysbot+gh@w3.org>
- Date: Mon, 12 Dec 2016 22:26:39 +0000
- To: public-media-capture-logs@w3.org
That's what the "Universal Serial Bus Device Class Definition for Video Devices Revision 1.5 August 9, 2012" gives us in e.g. its Section 4.2.2.3.2 Brightness Control: > This is used to specify the brightness. This is a relative value where increasing values indicate increasing brightness. The MIN and MAX values are sufficient to imply the resolution, so the RES value must always be 1. The MIN, MAX and default values are implementation dependent. This control must accept the GET_DEF request and return its default value. Those four controls are just pass-through to UVC controls, so I don't see how this Spec can impose restrictions on them. FTR I've always seen those controls as a 0-255 scale, 128 being the middle value (i.e. it behaves as a signed char). I'll add a comment with this info and link to the UVC standard. On the plus side, controls provide `max`,`min`, and `default` values, which would answer part of your question -- but now e.g. what would negative values do. I wonder how other hardware-dependent Specs would tackle this problem. -- GitHub Notification of comment by miguelao Please view or discuss this issue at https://github.com/w3c/mediacapture-image/issues/128#issuecomment-266573048 using your GitHub account
Received on Monday, 12 December 2016 22:26:45 UTC