[libcamera-devel] [PATCH v4 3/5] libcamera: controls: Reorder and update description of existing controls

[Laurent Pinchart]

Hi Naush,

Thank you for the patch.

On Fri, Apr 24, 2020 at 11:46:58AM +0100, Naushir Patuck wrote:
> Group AE, AWB, etc. controls together for accessibility.
> 
> Update descriptions for Contrast, Brightness, and Saturation controls.
> 
> Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> ---
>  src/libcamera/control_ids.yaml | 41 ++++++++++++++++++++--------------
>  1 file changed, 24 insertions(+), 17 deletions(-)
> 
> diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
> index d8bdb382..f7403081 100644
> --- a/src/libcamera/control_ids.yaml
> +++ b/src/libcamera/control_ids.yaml
> @@ -25,23 +25,6 @@ controls:
>  
>          \sa AeEnable
>  
> -  - AwbEnable:
> -      type: bool
> -      description: |
> -        Enable or disable the AWB.
> -
> -  - Brightness:
> -      type: int32_t
> -      description: Specify a fixed brightness parameter
> -
> -  - Contrast:
> -      type: int32_t
> -      description: Specify a fixed contrast parameter
> -
> -  - Saturation:
> -      type: int32_t
> -      description: Specify a fixed saturation parameter
> -
>    - ExposureTime:
>        type: int32_t
>        description: |
> @@ -58,4 +41,28 @@ controls:
>          colour channels. This value cannot be lower than 1.0.
>  
>          \sa ExposureTime AeEnable
> +
> +  - Brightness:
> +      type: float
> +      description: |
> +        Specify a fixed brightness parameter. Positive values (up to 65535.0)
> +        produce brighter images; negative values (up to -65536.0) produce darker
> +        images and 0.0 leaves pixels unchanged.

Maybe a bit of a stupid question, but if we use a float, the proposed
range seems a bit awkward to me. Should we go for a [-1.0, +1.0] range ?

> +
> +  - Contrast:
> +      type: float
> +      description:  |
> +        Specify a fixed contrast parameter. Normal contrast is given by the
> +        value 1.0; larger values produce images with more contrast.
> +
> +  - AwbEnable:
> +      type: bool
> +      description: |
> +        Enable or disable the AWB.
> +
> +  - Saturation:
> +      type: float
> +      description:  |
> +        Specify a fixed saturation parameter. Normal saturation is given by
> +        the value 1.0; larger values produce more saturated colours.

Is it worth adding that 0.0 produces greyscale images ?

Let's not spend too much time on this, I'm sure we'll have a chance to
rework these controls later anyway.

With the above two issues addressed,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

I can also update the patch when applying if you're fine with the above
proposals.

>  ...

-- 
Regards,

Laurent Pinchart