[PATCH v2 08/17] libtuning: module: awb: Add bayes AWB support

[Kieran Bingham]

Quoting Stefan Klug (2025-01-23 11:40:58)
> To support the bayesian AWB algorithm in libtuning, the necessary data
> needs to be collected and written to the tuning file.
> 
> Extend libtuning to calculate and output that additional data.
> 
> Prior probabilities and AwbModes are manually specified and not
> calculated in the tuning process. Add sample values from the RaspberryPi
> tuning files to the example config file.
> 
> Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>
> Reviewed-by: Paul Elder <paul.elder at ideasonboard.com>
> 
> ---
> 
> Changes in v2:
> - Collected tags
> - Fixed missing space
> - Reworked commit message
> - Add example prior probabilities from RaspberryPi
> ---
>  utils/tuning/config-example.yaml             | 44 +++++++++++++++++++-
>  utils/tuning/libtuning/modules/awb/awb.py    | 16 ++++---
>  utils/tuning/libtuning/modules/awb/rkisp1.py | 21 +++++++---
>  3 files changed, 68 insertions(+), 13 deletions(-)
> 
> diff --git a/utils/tuning/config-example.yaml b/utils/tuning/config-example.yaml
> index 1b7f52cd2fff..1bbb275778dc 100644
> --- a/utils/tuning/config-example.yaml
> +++ b/utils/tuning/config-example.yaml
> @@ -5,7 +5,49 @@ general:
>      do_alsc_colour: 1
>      luminance_strength: 0.5
>    awb:
> -    greyworld: 0
> +    # Algorithm can either be 'grey' or 'bayes'
> +    algorithm: bayes
> +    # Priors is only used for the bayes algorithm. They are defined in
> +    # logarithmic space. A good staring point is:
> +    # - lux: 0
> +    #   ct: [ 2000, 3000, 13000 ]
> +    #   probability: [ 1.0, 0.0, 0.0 ]
> +    # - lux: 800
> +    #   ct: [ 2000, 6000, 13000 ]
> +    #   probability: [ 0.0, 2.0, 2.0 ]
> +    # - lux: 1500
> +    #   ct: [ 2000, 4000, 6000, 6500, 7000, 13000 ]
> +    #   probability: [ 0.0, 1.0, 6.0, 7.0, 1.0, 1.0 ]
> +    priors:
> +      - lux: 0
> +        ct: [ 2000, 13000 ]
> +        probability: [ 0.0, 0.0 ]
> +    AwbMode:
> +      AwbAuto:
> +        lo: 2500
> +        hi: 8000
> +      AwbIncandescent:
> +        lo: 2500
> +        hi: 3000
> +      AwbTungsten:
> +        lo: 3000
> +        hi: 3500
> +      AwbFluorescent:
> +        lo: 4000
> +        hi: 4700
> +      AwbIndoor:
> +        lo: 3000
> +        hi: 5000
> +      AwbDaylight:
> +        lo: 5500
> +        hi: 6500
> +      AwbCloudy:
> +        lo: 6500
> +        hi: 8000
> +      # One custom mode can be defined if needed
> +      #AwbCustom:
> +      #  lo: 2000
> +      #  hi: 1300
>    macbeth:
>      small: 1
>      show: 0
> diff --git a/utils/tuning/libtuning/modules/awb/awb.py b/utils/tuning/libtuning/modules/awb/awb.py
> index c154cf3b8609..0dc4f59dcb26 100644
> --- a/utils/tuning/libtuning/modules/awb/awb.py
> +++ b/utils/tuning/libtuning/modules/awb/awb.py
> @@ -27,10 +27,14 @@ class AWB(Module):
>  
>          imgs = [img for img in images if img.macbeth is not None]
>  
> -        gains, _, _ = awb(imgs, None, None, False)
> -        gains = np.reshape(gains, (-1, 3))
> +        ct_curve, transverse_pos, transverse_neg = awb(imgs, None, None, False)
> +        ct_curve = np.reshape(ct_curve, (-1, 3))
> +        gains = [{
> +            'ct': int(v[0]),
> +            'gains': [float(1.0 / v[1]), float(1.0 / v[2])]
> +        } for v in ct_curve]
> +
> +        return {'colourGains': gains,
> +                'transversePos': transverse_pos,
> +                'transverseNeg': transverse_neg}
>  
> -        return [{
> -                    'ct': int(v[0]),
> -                    'gains': [float(1.0 / v[1]), float(1.0 / v[2])]
> -                } for v in gains]
> diff --git a/utils/tuning/libtuning/modules/awb/rkisp1.py b/utils/tuning/libtuning/modules/awb/rkisp1.py
> index 0c95843b83d3..d562d26eb8cc 100644
> --- a/utils/tuning/libtuning/modules/awb/rkisp1.py
> +++ b/utils/tuning/libtuning/modules/awb/rkisp1.py
> @@ -6,9 +6,6 @@
>  
>  from .awb import AWB
>  
> -import libtuning as lt
> -
> -
>  class AWBRkISP1(AWB):
>      hr_name = 'AWB (RkISP1)'
>      out_name = 'Awb'
> @@ -20,8 +17,20 @@ class AWBRkISP1(AWB):
>          return True
>  
>      def process(self, config: dict, images: list, outputs: dict) -> dict:
> -        output = {}
> -
> -        output['colourGains'] = self.do_calculation(images)
> +        if not 'awb' in config['general']:
> +            raise ValueError('AWB configuration missing')
> +        awb_config = config['general']['awb']
> +        algorithm = awb_config['algorithm']
> +
> +        output = {'algorithm': algorithm}
> +        data = self.do_calculation(images)
> +        if algorithm == 'grey':
> +            output['colourGains'] = data['colourGains']

How come there's no output.update(data) on this code path ? (I don't
know what it does yet, just noticing that it's only on one path).

Is there any argument to output the colourGains for greyworld as well as
bayes to the same file ? or is Manual ColourTemperature handled
distinctly with bayes (I presume it just overrides whatever the bayes
would have predicted to be the colour temperature)


> +        elif algorithm == 'bayes':
> +            output['AwbMode'] = awb_config['AwbMode']
> +            output['priors'] = awb_config['priors']
> +            output.update(data)
> +        else:
> +            raise ValueError(f"Unknown AWB algorithm {output['algorithm']}")
>  
>          return output
> -- 
> 2.43.0
>