[libcamera-devel,2/7] utils: libtuning: modules: Add ALSC module
diff mbox series

Message ID 20221006120105.3861831-3-paul.elder@ideasonboard.com
State Superseded
Headers show
Series
  • utils: tuning: Add a new tuning infrastructure
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Commit Message

Paul Elder Oct. 6, 2022, 12:01 p.m. UTC
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.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
---
 utils/tuning/libtuning/modules/__init__.py |   1 +
 utils/tuning/libtuning/modules/alsc.py     | 321 +++++++++++++++++++++
 2 files changed, 322 insertions(+)
 create mode 100644 utils/tuning/libtuning/modules/alsc.py

Patch
diff mbox series

diff --git a/utils/tuning/libtuning/modules/__init__.py b/utils/tuning/libtuning/modules/__init__.py
index e69de29b..f41ef550 100644
--- a/utils/tuning/libtuning/modules/__init__.py
+++ b/utils/tuning/libtuning/modules/__init__.py
@@ -0,0 +1 @@ 
+from libtuning.modules.alsc import ALSC
diff --git a/utils/tuning/libtuning/modules/alsc.py b/utils/tuning/libtuning/modules/alsc.py
new file mode 100644
index 00000000..788cf2a9
--- /dev/null
+++ b/utils/tuning/libtuning/modules/alsc.py
@@ -0,0 +1,321 @@ 
+from .module import Module
+
+import libtuning as lt
+import libtuning.utils as utils
+
+import decimal
+import numbers
+import numpy as np
+from typing import Callable
+
+
+class ALSC(Module):
+    def __init__(self, *,
+                 do_color: lt.param,
+                 debug: list,
+                 luminance_strength: lt.param,
+                 sector_shape: tuple,
+                 sector_x_gradient: lt.gradient.Gradient,
+                 sector_y_gradient: lt.gradient.Gradient,
+                 sector_x_remainder: lt.remainder = None,
+                 sector_y_remainder: lt.remainder = None,
+                 sector_average_function: Callable,
+                 sector_average_function_parameters: list = [],
+                 smoothing_function: Callable,
+                 smoothing_parameters: list = [],
+                 output_type: type,
+                 output_color_channels: list,
+                 output_range: tuple):
+        super().__init__()
+        self.hr_name = "ALSC"
+        self.name = "alsc"
+        self.options = {}
+
+        if (sector_x_gradient is lt.gradient.Linear and sector_x_remainder is None):
+            raise ValueError('sector_x_remainder must be specified if sector_x_gradient is Linear')
+
+        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.do_color = do_color
+        self.luminance_strength = luminance_strength
+
+        self.debug = debug
+
+        self.sector_shape = sector_shape
+        self.sector_x_gradient = sector_x_gradient(sector_x_remainder)
+        self.sector_y_gradient = sector_y_gradient(sector_y_remainder)
+        self.sector_average_function = sector_average_function(sector_average_function_parameters)
+
+        self.smoothing_function = smoothing_function(smoothing_parameters)
+
+        # todo This isn't actually used. Can we assume/force float? Is there a
+        # use case for non-float? Or maybe we should use numpy types like
+        # float64? I don't think it makes a difference in the output tuning
+        # anyway though.
+        self.output_type = output_type
+
+        # This isn't used for now. Once we add support for two green channels
+        # we can.
+        self.output_color_channels = output_color_channels
+
+        self.output_range = output_range
+
+    def enumerate_alsc_images(images):
+        for image in images:
+            if image.alsc_only:
+                yield image
+
+    def __validateConfig__(self, config: dict) -> bool:
+        if not super().__validateConfig__(config):
+            return False
+
+        conf = config[self]
+        valid = True
+
+        lum_key = self.luminance_strength.name
+        color_key = self.do_color.name
+
+        if lum_key not in conf and self.luminance_strength.isRequired():
+            utils.eprint(f'{lum_key} is not in config')
+            valid = False
+
+        if lum_key in conf and (conf[lum_key] < 0 or conf[lum_key] > 1):
+            utils.eprint(f'Warning: {lum_key} is not in range [0, 1]; defaulting to 0.5')
+
+        if color_key not in conf and self.do_color.isRequired():
+            utils.eprint(f'{color_key} is not in config')
+            valid = False
+
+        return valid
+
+    def _getGrid(self, channel, image):
+        # List of number of pixels in each sector
+        sectors_x = self.sector_x_gradient.distribute(image.w, self.sector_shape[0])
+        sectors_y = self.sector_y_gradient.distribute(image.h, 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(channel[r:r + y, c:c + x]))
+                c += x
+            r += y
+
+        return np.array(grid)
+
+    # @return Image color temperature, flattened array of red calibration table
+    #         (containing {sector size} elements), flattened array of blue
+    #         calibration table, flattened array of (red's) green calibration
+    #         table, flattened array of (blue's) green calibration table
+
+    def _doSingleAlsc(self, image: lt.Image, do_alsc_colour: bool):
+        # Get channel in correct order: [R, GR, GB, B]
+        channels = [image.channels[i] for i in image.order]
+
+        channels.append(np.mean((channels[color.GR:color.GB + 1]), axis=0))
+
+        g = self._getGrid(av_ch_g, image) - image.blacklevel_16
+        cg = np.reshape(1 / g, self.sector_shape[::-1])
+        cg = self.smoothing_function.smoothing(cg, 3)
+        cg = cg / np.min(cg)
+
+        if not do_alsc_colour:
+            return image.color, None, None, cg.flatten(), cg.flatten()
+
+        r = self._getGrid(channels[0], image) - image.blacklevel_16
+        cr = np.reshape(g / r, self.sector_shape[::-1])
+        cr = self.smoothing_function.smoothing(cr, 3)
+
+        b = self._getGrid(channels[3], image) - image.blacklevel_16
+        cb = np.reshape(g / b, self.sector_shape[::-1])
+        cb = self.smoothing_function.smoothing(cb, 3)
+
+        # todo implement debug
+
+        return image.color, cr.flatten(), cb.flatten(), cg.flatten(), cg.flatten()
+
+    # todo Figure out if we can do something cooler if we can keep the greens
+    # separate. For now, just average them and use the average, but duplicate
+    # them so that it's easier to handle them in the future, especially since
+    # some platforms have separate tables for GR and GB.
+    #
+    # todo Should we return a third shading table for the average of greens?
+    # For platforms that only want one green, as opposed to just using red's
+    # green shading table
+    #
+    # @return Red shading table, Blue shading table, (red's) Green shading
+    #         table, (blue's) Green shading table, number of images processed
+
+    def _doAllAlsc(self, images: list, do_alsc_colour: bool, general_conf: dict) -> (list, list, list, numbers.Number, int):
+        # List of colour temperatures
+        list_col = []
+        # Associated calibration tables
+        list_cr = []
+        list_cb = []
+        list_cg1 = []
+        list_cg2 = []
+        count = 0
+        for image in enumerate_alsc_images(images):
+            col, cr, cb, cg1, cg2 = self._doSingleAlsc(image, do_alsc_colour)
+            list_col.append(col)
+            list_cr.append(cr)
+            list_cb.append(cb)
+            list_cg1.append(cg1)
+            list_cg2.append(cg2)
+            count += 1
+
+        # Convert to numpy array for data manipulation
+        list_col = np.array(list_col)
+        list_cr = np.array(list_cr)
+        list_cb = np.array(list_cb)
+        list_cg1 = np.array(list_cg1)
+        list_cg2 = np.array(list_cg2)
+
+        cal_cr_list = []
+        cal_cb_list = []
+
+        # Note: Calculation of average corners and center of the shading tables
+        # has been removed (which ctt had, as it was being unused)
+
+        # todo Handle the second green table
+
+        # Average all values for luminance shading and return one table for all temperatures
+        lum_lut = roundWithSigfigs(np.mean(list_cg1, axis=0), self.output_range)
+
+        if not do_alsc_colour:
+            return None, None, lum_lut, lum_lut, count
+
+        for ct in sorted(set(list_col)):
+            # Average tables for the same colour temperature
+            indices = np.where(list_col == ct)
+            ct = int(ct)
+            t_r = utils.roundWithSigfigs(np.mean(list_cr[indices], axis=0),
+                                         self.output_range)
+            t_b = utils.roundWithSigfigs(np.mean(list_cb[indices], axis=0),
+                                         self.output_range)
+
+            cr_dict = {
+                'ct': ct,
+                'table': list(t_r)
+            }
+            cb_dict = {
+                'ct': ct,
+                'table': list(t_b)
+            }
+            cal_cr_list.append(cr_dict)
+            cal_cb_list.append(cb_dict)
+
+        return cal_cr_list, cal_cb_list, lum_lut, lum_lut, count
+
+    # @brief Calculate sigma from two adjacent gain tables
+    def _calcSigma(self, g1, g2):
+        g1 = np.reshape(g1, self.sector_shape[::-1])
+        g2 = np.reshape(g2, self.sector_shape[::-1])
+
+        # Apply gains to gain table
+        gg = g1 / g2
+        if np.mean(gg) < 1:
+            gg = 1 / gg
+
+        # For each internal patch, compute average difference between it and
+        # its 4 neighbours, then append to list
+        diffs = []
+        for i in range(self.sector_shape[1] - 2):
+            for j in range(self.sector_shape[0] - 2):
+                # Indexing is incremented by 1 since all patches on borders are
+                # not counted
+                diff = np.abs(gg[i + 1][j + 1] - gg[i][j + 1])
+                diff += np.abs(gg[i + 1][j + 1] - gg[i + 2][j + 1])
+                diff += np.abs(gg[i + 1][j + 1] - gg[i + 1][j])
+                diff += np.abs(gg[i + 1][j + 1] - gg[i + 1][j + 2])
+                diffs.append(diff / 4)
+
+        mean_diff = np.mean(diffs)
+        return(np.round(mean_diff, 5))
+
+    # @brief Obtains sigmas for red and blue, effectively a measure of the
+    # 'error'
+    def _getSigma(self, cal_cr_list, cal_cb_list):
+        # Provided colour alsc tables were generated for two different colour
+        # temperatures sigma is calculated by comparing two calibration temperatures
+        # adjacent in colour space
+
+        color_temps = [cal['ct'] for cal in cal_cr_list]
+
+        # Calculate sigmas for each adjacent color_temps and return worst one
+        sigma_rs = []
+        sigma_bs = []
+        for i in range(len(color_temps) - 1):
+            sigma_rs.append(self._calcSigma(cal_cr_list[i]['table'], cal_cr_list[i + 1]['table']))
+            sigma_bs.append(self._calcSigma(cal_cb_list[i]['table'], cal_cb_list[i + 1]['table']))
+
+        # Return maximum sigmas, not necessarily from the same colour
+        # temperature interval
+        sigma_r = max(sigma_rs) if sigma_rs else 0.005
+        sigma_b = max(sigma_bs) if sigma_bs else 0.005
+
+        return sigma_r, sigma_b
+
+    def __process__(self, args, config: dict, images: list, outputs: dict) -> dict:
+        output = {
+            'omega': 1.3,
+            'n_iter': 100,
+            'luminance_strength': 0.7
+        }
+
+        conf = config[self]
+        general_conf = config['general']
+
+        do_alsc_colour = self.do_color.getValue(conf)
+
+        # todo I have no idea where this input parameter is used
+        luminance_strength = self.luminance_strength.getValue(conf)
+        if luminance_strength < 0 or luminance_strength > 1:
+            luminance_strength = 0.5
+
+        output['luminance_strength'] = luminance_strength
+
+        # todo Validate images from greyscale camera and force grescale mode
+        # todo Debug functionality
+
+        alsc_out = self._doAllAlsc(images, do_alsc_colour, general_conf)
+        # todo Handle the second green lut
+        cal_cr_list, cal_cb_list, luminance_lut, _, count = alsc_out
+
+        output['luminance_lut'] = luminance_lut
+
+        if not do_alsc_colour:
+            output['n_iter'] = 0
+            return output
+
+        output['calibrations_Cr'] = cal_cr_list
+        output['calibrations_Cb'] = cal_cb_list
+
+        # The sigmas determine the strength of the adaptive algorithm, that
+        # cleans up any lens shading that has slipped through the alsc. These
+        # are determined by measuring a 'worst-case' difference between two
+        # alsc tables that are adjacent in colour space. If, however, only one
+        # colour temperature has been provided, then this difference can not be
+        # computed as only one table is available.
+        # To determine the sigmas you would have to estimate the error of an
+        # alsc table with only the image it was taken on as a check. To avoid
+        # circularity, dfault exaggerated sigmas are used, which can result in
+        # too much alsc and is therefore not advised.
+        # In general, just take another alsc picture at another colour
+        # temperature!
+
+        if count == 1:
+            output['sigma'] = 0.005
+            output['sigma_Cb'] = 0.005
+            utils.eprint('Warning: Only one alsc calibration found; standard sigmas used for adaptive algorithm.')
+            return output
+
+        # Obtain worst-case scenario residual sigmas
+        sigma_r, sigma_b = self._getSigma(self, cal_cr_list, cal_cb_list)
+        output['sigma'] = np.round(sigma_r, 5)
+        output['sigma_Cb'] = np.round(sigma_b, 5)
+
+        return output