Hi Laurent, On Sat, 25 Aug 2018, Laurent Pinchart wrote: > Hi Guennadi, > > On Friday, 3 August 2018 14:07:12 EEST Guennadi Liakhovetski wrote: > > Hi Laurent, > > > > Thanks for the review. A general note: I think you're requesting a rather > > detailed information about many parameters. That isn't a problem by > > itself, however, it is difficult to obtain some of that information. I'll > > address whatever comments I can in an updated version, just answering some > > questions here. I directed youor questions, that I couldn't answer myself > > to respective people, but I have no idea if and when I get replies. So, > > it's up to you whether to wait for that additional information or to take > > at least what we have now. > > I've replied to v2, and apart from a few minor points, I think we can apply > the current version. There are a few small questions I would still like to > have answers to, but if it takes to long to obtain that, let's not miss v4.20. > > > On Sun, 29 Jul 2018, Laurent Pinchart wrote: > > > On Saturday, 23 December 2017 13:11:00 EEST Guennadi Liakhovetski wrote: > > >> From: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxx> > > >> > > >> D4M is a mobile model from the D4XX family of Intel RealSense cameras. > > >> This patch adds a descriptor for it, which enables reading per-frame > > >> metadata from it. > > >> > > >> Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxx> > > >> --- > > >> > > >> Documentation/media/uapi/v4l/pixfmt-meta-d4xx.rst | 202 ++++++++++++++++ > > >> drivers/media/usb/uvc/uvc_driver.c | 11 ++ > > >> include/uapi/linux/videodev2.h | 1 + > > >> 3 files changed, 214 insertions(+) > > >> create mode 100644 Documentation/media/uapi/v4l/pixfmt-meta-d4xx.rst > > >> > > >> diff --git a/Documentation/media/uapi/v4l/pixfmt-meta-d4xx.rst > > >> b/Documentation/media/uapi/v4l/pixfmt-meta-d4xx.rst new file mode 100644 > > >> index 0000000..950780d > > >> --- /dev/null > > >> +++ b/Documentation/media/uapi/v4l/pixfmt-meta-d4xx.rst > > [snip] > > > >> + * - :cspan:`1` *Configuration* > > >> + * - __u32 ID > > >> + - 0x80000002 > > >> + * - __u32 Size > > >> + - Size in bytes (currently 40) > > >> + * - __u32 Version > > >> + - Version of the struct > > >> + * - __u32 Flags > > >> + - A bitmask of flags: see [4_] below > > >> + * - __u8 Hardware type > > >> + - Camera hardware version [5_] > > >> + * - __u8 SKU ID > > >> + - Camera hardware configuration [6_] > > >> + * - __u32 Cookie > > >> + - Internal synchronisation > > > > > > Internal synchronisation with what ? :-) > > This is still something I'd like to understand (and I understand it may still > take time to receive an answer from the right person). Sorry, no idea, that flag wasn't even set when I was testing it. > > >> + * - __u16 Format > > >> + - Image format code [7_] > > >> + * - __u16 Width > > >> + - Width in pixels > > >> + * - __u16 Height > > >> + - Height in pixels > > >> + * - __u16 Framerate > > >> + - Requested framerate > > > > > > What's the unit of this value ? > > > > Is anything other than frames per second used in V4L? > > V4L2 expresses the frame rate as a fraction, hence my question, to know > whether this field contained the number of frames per second as an integer, or > used a different representation (such as a fixed point decimal value for > instance). Nono, sorry, just an integer FPS. Thanks Guennadi > > >> + * - __u16 Trigger > > >> + - Byte 0: bit 0: depth and RGB are synchronised, bit 1: external > > >> trigger > > >> + > > >> +.. _1: > > >> + > > >> +[1] > > >> https://docs.microsoft.com/en-us/windows-hardware/drivers/stream/uvc-ext > > >> ensions-1-5 > > > > > > Should we at some point replicate that documentation in the V4L2 spec ? > > > Without copying it of course, as that would be a copyright violation. > > > > Well, we don't replicate the UVC itself or any other standards, do we? Of > > course, that document doesn't have the same status as an official > > vendor-neutral standard, but still, we don't replicate data sheets either. > > Besides, I think there are cameras that use this, and windows supports > > this, so, don't think it will disappear overnight... > > Probably not overnight, you're right. I'm a bit worried about the link > becoming invalid though. In any case that's not a blocker, but I might at some > point decide to replicate the documentation. > > [snip] > > -- > Regards, > > Laurent Pinchart > > >
