[libcamera-devel] [PATCH v2 02/11] utils: libtuning: modules: Add ALSC module

[Paul Elder]

On Wed, Nov 09, 2022 at 12:29:50AM +0200, Laurent Pinchart wrote:
> Hi Paul,
> 
> Thank you for the patch.
> 
> On Sat, Oct 22, 2022 at 03:23:01PM +0900, Paul Elder via libcamera-devel wrote:
> > Add an ALSC module to libtuning's collection of modules. It is based on
> > raspberrypi's ctt's ALSC, but customizable for different lens shading
> > table sizes, among other things.
> 
> I think I would name the module LSC, not ALSC, as there's nothing
> adaptative here.
> 
> > Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
> > 
> > ---
> > Changes in v2:
> > - fix python errors
> > - fix style
> > - add SPDX and copyright
> > - don't call super().validateConfig()
> > - fix sector splitting
> >   - i forgot that we have to half the image size for each color channel
> > - make the base ALSC module into an abstract module, which can be easily
> >   used by other platforms to derive their own ALSC modules (see rkisp1's
> >   module later in this series; i think it's quite nice)
> > ---
> >  .../tuning/libtuning/modules/alsc/__init__.py |  5 ++
> >  utils/tuning/libtuning/modules/alsc/alsc.py   | 78 +++++++++++++++++++
> >  2 files changed, 83 insertions(+)
> >  create mode 100644 utils/tuning/libtuning/modules/alsc/__init__.py
> >  create mode 100644 utils/tuning/libtuning/modules/alsc/alsc.py
> > 
> > diff --git a/utils/tuning/libtuning/modules/alsc/__init__.py b/utils/tuning/libtuning/modules/alsc/__init__.py
> > new file mode 100644
> > index 00000000..a8f28923
> > --- /dev/null
> > +++ b/utils/tuning/libtuning/modules/alsc/__init__.py
> > @@ -0,0 +1,5 @@
> > +# SPDX-License-Identifier: GPL-2.0-or-later
> > +#
> > +# Copyright (C) 2022, Paul Elder <paul.elder at ideasonboard.com>
> > +
> > +from libtuning.modules.alsc.alsc import ALSC
> > diff --git a/utils/tuning/libtuning/modules/alsc/alsc.py b/utils/tuning/libtuning/modules/alsc/alsc.py
> > new file mode 100644
> > index 00000000..b708b28d
> > --- /dev/null
> > +++ b/utils/tuning/libtuning/modules/alsc/alsc.py
> > @@ -0,0 +1,78 @@
> > +# SPDX-License-Identifier: BSD-2-Clause
> > +#
> > +# Copyright (C) 2019, Raspberry Pi Ltd
> > +# Copyright (C) 2022, Paul Elder <paul.elder at ideasonboard.com>
> > +
> > +from ..module import Module
> > +
> > +import libtuning as lt
> > +import libtuning.utils as utils
> > +
> > +import numpy as np
> > +
> > +
> > +class ALSC(Module):
> > +    type = 'alsc'
> > +    hr_name = 'ALSC (Base)'
> > +    out_name = 'GenericALSC'
> > +
> > +    def __init__(self, *,
> > +                 debug: list,
> > +                 sector_shape: tuple,
> > +                 sector_x_gradient: lt.Gradient,
> > +                 sector_y_gradient: lt.Gradient,
> > +                 sector_average_function: lt.Average,
> > +                 smoothing_function: lt.Smoothing):
> > +        super().__init__()
> > +
> > +        if (sector_x_gradient is lt.gradient.Linear and sector_x_remainder is None):
> 
> No need for parentheses. Same below.
> 
> > +            raise ValueError('sector_x_remainder must be specified if sector_x_gradient is Linear')
> 
> sector_x_remainder is not defined. Same for y. The "is
> lt.gradient.Linear" test is always false, which is something you
> probably want to fix too.

Actually this (and the next) can be dropped because the remainder is
passed to the Linear constructor, if that's what's passed.

> I assume all this will be revisited (I don't think that generic gradient
> types will be useful), for now,

(I think it might, but I guess we'll see)

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


Thanks,

Paul

> 
> > +
> > +        if (sector_y_gradient is lt.gradient.Linear and sector_y_remainder is None):
> > +            raise ValueError('sector_y_remainder must be specified if sector_y_gradient is Linear')
> > +
> > +        self.debug = debug
> > +
> > +        self.sector_shape = sector_shape
> > +        self.sector_x_gradient = sector_x_gradient
> > +        self.sector_y_gradient = sector_y_gradient
> > +        self.sector_average_function = sector_average_function
> > +
> > +        self.smoothing_function = smoothing_function
> > +
> > +    def _enumerate_alsc_images(self, images):
> > +        for image in images:
> > +            if image.alsc_only:
> > +                yield image
> > +
> > +    def _get_grid(self, channel, img_w, img_h):
> > +        # List of number of pixels in each sector
> > +        sectors_x = self.sector_x_gradient.distribute(img_w / 2, self.sector_shape[0])
> > +        sectors_y = self.sector_y_gradient.distribute(img_h / 2, self.sector_shape[1])
> > +
> > +        grid = []
> > +
> > +        r = 0
> > +        for y in sectors_y:
> > +            c = 0
> > +            for x in sectors_x:
> > +                grid.append(self.sector_average_function.average(channel[r:r + y, c:c + x]))
> > +                c += x
> > +            r += y
> > +
> > +        return np.array(grid)
> > +
> > +    def _lsc_single_channel(self, channel: np.array,
> > +                            image: lt.Image, green_grid: np.array = None):
> > +        grid = self._get_grid(channel, image.w, image.h)
> > +        grid -= image.blacklevel_16
> > +        if green_grid is None:
> > +            table = np.reshape(1 / grid, self.sector_shape[::-1])
> > +        else:
> > +            table = np.reshape(green_grid / grid, self.sector_shape[::-1])
> > +        table = self.smoothing_function.smoothing(table)
> > +
> > +        if green_grid is None:
> > +            table = table / np.min(table)
> > +
> > +        return table, grid
> 
> -- 
> Regards,
> 
> Laurent Pinchart