Hi Guennadi, On Wednesday 18 March 2015 22:49:07 Guennadi Liakhovetski wrote: > On Tue, 17 Mar 2015, Oliver Lehmann wrote: > > Hi, > > > > I'm using v4l2 on FreeBSD but I hope this doesn't matter that much. > > I got a new MS LifeCam Studio HD which makes quite good pictures > > because of its focus possibilites. > > > > When I use the original software provided by MS the "autofocus" > > feature works damn good. With v4l2, autofocus is enabled but it > > just does not focus. Disabling autofocus and setting focus manually > > does work (and in my case this is sufficient) > > > > Another point is, that this cam can record pictures with 8 megapixel > > which results in 3840x2160 image files. This "8MP mode" and the 1080p > > mode is only available for snapshot pictures. The highest resolution > > supported for videos is 720p. > > I'm not sure I can help, at least definitely not until I know details. But > in either case I'd be interested to know details of this camera. Can you > find out what driver is serving it, what standard it is? Looking at the > Microsoft so veeeery "technical" data sheet it says, it is compatible with > Android. So, it hints at it being a UVC camera. > > As for the actual question, I have no idea how they implement still > images: the UVC standard defines two methods for higher-resolution still > image capture: either using the "still image trigger control" or a > dedicated bulk pipeline (and a hardware button if there is one on your > camera?) FWIW, in either case I'm not sure whether the driver supports any > of those methods. I think bulk pipe support has been added to it at some > point, but what concerns switching... Not sure really, sorry. Still image capture isn't implemented in the uvcvideo driver. Part of the reason is that I never managed to get my hands on a device that implements it (but I haven't tried very hard either). > But if you just try to be opportunistic and try cheese - it has a separate > setting for still images, so, maybe I'm way behind the time and everything > is working already? > > Thanks > Guennadi > > > All I want is recording snapshot images and I do not need the video > > capability at all. > > > > I wonder how I can capture those big 8MP images? With mplayer I'm > > only able toe capture 720p at max. I guess because mplayer just > > accesses the video mode and takes a single frame. > > > > mplayer tv:// -tv driver=v4l2:device=/dev/video0:width=1280:height=720 > > -frames 1 -vo jpeg > > > > I wonder if there is a possibility to access the cam in the > > I-call-it-snapshot-mode to take single pictures with higher resolutions? -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
