[PATCH v2 4/6] ipa: rkisp1: blc: Report sensor black levels in metadata

[Paul Elder]

On Wed, Jul 03, 2024 at 12:39:51PM +0200, Stefan Klug wrote:
> Add sensor black levels to the metadata of the rkisp1 pipeline.
> 
> Additionally enable raw support for this algorithm and add it to
> uncalibrated.yaml, so that black levels get reported when capturing
> tuning images. This is a bit of a hack, because no actual black level
> correction is taking place in raw mode, but it is the easiest way to get
> blacklevel reported for raw streams.
> 
> Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>

Reviewed-by: Paul Elder <paul.elder at ideasonboard.com>

> ---
>  src/ipa/rkisp1/algorithms/blc.cpp     | 28 +++++++++++++++++++++++++++
>  src/ipa/rkisp1/algorithms/blc.h       |  5 ++++-
>  src/ipa/rkisp1/data/uncalibrated.yaml |  1 +
>  3 files changed, 33 insertions(+), 1 deletion(-)
> 
> diff --git a/src/ipa/rkisp1/algorithms/blc.cpp b/src/ipa/rkisp1/algorithms/blc.cpp
> index 87025e4f8c72..71c62b009707 100644
> --- a/src/ipa/rkisp1/algorithms/blc.cpp
> +++ b/src/ipa/rkisp1/algorithms/blc.cpp
> @@ -9,6 +9,8 @@
>  
>  #include <libcamera/base/log.h>
>  
> +#include <libcamera/control_ids.h>
> +
>  #include "libcamera/internal/yaml_parser.h"
>  
>  /**
> @@ -38,6 +40,13 @@ LOG_DEFINE_CATEGORY(RkISP1Blc)
>  BlackLevelCorrection::BlackLevelCorrection()
>  	: tuningParameters_(false)
>  {
> +	/*
> +	 * This is a bit of a hack. In raw mode no black level correction
> +	 * happens. This flag is used to ensure the metadata gets populated with
> +	 * the black level which is needed to capture proper raw images for
> +	 * tuning.
> +	 */
> +	supportsRaw_ = true;
>  }
>  
>  /**
> @@ -107,6 +116,9 @@ void BlackLevelCorrection::prepare([[maybe_unused]] IPAContext &context,
>  				   [[maybe_unused]] IPAFrameContext &frameContext,
>  				   rkisp1_params_cfg *params)
>  {
> +	if (context.configuration.raw)
> +		return;
> +
>  	if (frame > 0)
>  		return;
>  
> @@ -125,6 +137,22 @@ void BlackLevelCorrection::prepare([[maybe_unused]] IPAContext &context,
>  	params->module_cfg_update |= RKISP1_CIF_ISP_MODULE_BLS;
>  }
>  
> +/**
> + * \copydoc libcamera::ipa::Algorithm::process
> + */
> +void BlackLevelCorrection::process([[maybe_unused]] IPAContext &context,
> +				   [[maybe_unused]] const uint32_t frame,
> +				   [[maybe_unused]] IPAFrameContext &frameContext,
> +				   [[maybe_unused]] const rkisp1_stat_buffer *stats,
> +				   [[maybe_unused]] ControlList &metadata)
> +{
> +	metadata.set(controls::SensorBlackLevels,
> +		     { static_cast<int32_t>(blackLevelRed_),
> +		       static_cast<int32_t>(blackLevelGreenR_),
> +		       static_cast<int32_t>(blackLevelGreenB_),
> +		       static_cast<int32_t>(blackLevelBlue_) });
> +}
> +
>  REGISTER_IPA_ALGORITHM(BlackLevelCorrection, "BlackLevelCorrection")
>  
>  } /* namespace ipa::rkisp1::algorithms */
> diff --git a/src/ipa/rkisp1/algorithms/blc.h b/src/ipa/rkisp1/algorithms/blc.h
> index 460ebcc15739..4ecac233f88b 100644
> --- a/src/ipa/rkisp1/algorithms/blc.h
> +++ b/src/ipa/rkisp1/algorithms/blc.h
> @@ -23,7 +23,10 @@ public:
>  	void prepare(IPAContext &context, const uint32_t frame,
>  		     IPAFrameContext &frameContext,
>  		     rkisp1_params_cfg *params) override;
> -
> +	void process(IPAContext &context, const uint32_t frame,
> +		     IPAFrameContext &frameContext,
> +		     const rkisp1_stat_buffer *stats,
> +		     ControlList &metadata) override;
>  private:
>  	bool tuningParameters_;
>  	int16_t blackLevelRed_;
> diff --git a/src/ipa/rkisp1/data/uncalibrated.yaml b/src/ipa/rkisp1/data/uncalibrated.yaml
> index a7bbd8d84263..609012967e02 100644
> --- a/src/ipa/rkisp1/data/uncalibrated.yaml
> +++ b/src/ipa/rkisp1/data/uncalibrated.yaml
> @@ -5,4 +5,5 @@ version: 1
>  algorithms:
>    - Agc:
>    - Awb:
> +  - BlackLevelCorrection:
>  ...
> -- 
> 2.43.0
>