[libcamera-devel] [PATCH 01/13] libcamera: controls: Destage 'SensorTimestamp'

[Kieran Bingham]

Hi Jacopo,

On 19/04/2021 14:14, Jacopo Mondi wrote:
> Destage the 'SensorTimestamp' control, which is used by pipeline
> handlers to report the time when the first active line of the sensor's
> pixel array is exposed.
> 
> Reviewed-by: Hirokazu Honda <hiroh at chromium.org>
> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  src/libcamera/control_ids.yaml | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
> index b4771f9def89..88d81ac4cccc 100644
> --- a/src/libcamera/control_ids.yaml
> +++ b/src/libcamera/control_ids.yaml
> @@ -360,6 +360,20 @@ controls:
>  
>        size: [2]
>  
> +  - SensorTimestamp:
> +      type: int64_t
> +      description: |
> +        The time when the first row of the image sensor active array is exposed.
> +
> +        The timestamp, expressed in nanoseconds, represents a monotonically
> +        increasing counter since the system boot time, as defined by the
> +        Linux-specific CLOCK_BOOTTIME clock id.
> +
> +        The SensorTimestamp control can only be returned in metadata.
> +
> +        \todo Define how the sensor timestamp has to be used in the reprocessing
> +        use case.

This reads fine to me.

I'm not sure if it's relevant to restrict/tie the timestamp to
CLOCK_BOOTTIME, but I don't know any better, and I think you've already
discussed that elsewhere.


Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>


> +
>    # ----------------------------------------------------------------------------
>    # Draft controls section
>  
> @@ -547,13 +561,6 @@ controls:
>            value: 3
>            description: The AWB algorithm is locked.
>  
> -  - SensorTimestamp:
> -      type: int64_t
> -      draft: true
> -      description: |
> -       Control to report the start of exposure of the first row of the captured
> -       image. Currently identical to ANDROID_SENSOR_TIMESTAMP.
> -
>    - SensorRollingShutterSkew:
>        type: int64_t
>        draft: true
> 

-- 
Regards
--
Kieran