[libcamera-devel] [PATCH 1/3] src: ipa: raspberrypi: Avoid AGC filtering when both gain and shutter specified

[Laurent Pinchart]

Hi David,

Thank you for the patch.

On Wed, Nov 25, 2020 at 11:36:38AM +0000, David Plowman wrote:
> When both gain and shutter have been directly specified, do not filter
> slowly towards those target values, but adopt them immediately. This
> should match user expectations better.
> 
> Signed-off-by: David Plowman <david.plowman at raspberrypi.com>

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

> ---
>  src/ipa/raspberrypi/controller/rpi/agc.cpp | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/src/ipa/raspberrypi/controller/rpi/agc.cpp b/src/ipa/raspberrypi/controller/rpi/agc.cpp
> index 4c56bdc9..30a1c1c1 100644
> --- a/src/ipa/raspberrypi/controller/rpi/agc.cpp
> +++ b/src/ipa/raspberrypi/controller/rpi/agc.cpp
> @@ -588,7 +588,12 @@ bool Agc::applyDigitalGain(double gain, double target_Y)
>  
>  void Agc::filterExposure(bool desaturate)
>  {
> -	double speed = frame_count_ <= config_.startup_frames ? 1.0 : config_.speed;
> +	double speed = config_.speed;
> +	// AGC adapts instantly if both shutter and gain are directly specified
> +	// or we're in the startup phase.
> +	if ((status_.fixed_shutter && status_.fixed_analogue_gain) ||
> +	    frame_count_ <= config_.startup_frames)
> +		speed = 1.0;
>  	if (filtered_.total_exposure == 0.0) {
>  		filtered_.total_exposure = target_.total_exposure;
>  		filtered_.total_exposure_no_dg = target_.total_exposure_no_dg;

-- 
Regards,

Laurent Pinchart