Re: [Patch v4 12/12] Documention: v4l: Documentation for HEVC CIDs

Smitha T Murthy
2017-04-07T12:06:40Z

On Fri, 2017-04-07 at 12:26 +0200, Sylwester Nawrocki wrote:
> On 04/07/2017 12:03 PM, Smitha T Murthy wrote:
> >>> +``V4L2_CID_MPEG_VIDEO_HEVC_LF``
> >>> + Indicates loop filtering. Control ID 0 indicates loop filtering
> >>> + is enabled and when set to 1 indicates no filter.
> >>
> >> "Setting this control to 0 enables loop filtering, setting this control
> >> to 1 disables loop filtering." ?
> >>
> >> Couldn't the meaning be inverted, so setting the control to 0 disables
> >> the loop filtering?
> >>
> >>From register point of view, this control value needs be 0 to enable
> > loop filtering.
>
> OK, this is true for our specific hardware/firmware implementation.
>
> In general, for this user space interface I would rather define that
> boolean control so value 1 enables LF and value 0 disables LF.
> The driver could simply negate the value when writing registers.
>
> BTW we might need to specify type of the control here as Hans suggested
> commenting on other control.
>
> --
> Regards,
> Sylwester
>
Ok I will change the implementation from the driver for this control.
Yes in the next version I will add the type of the control for all.

Thank you for the review.

Regards,
Smitha