249 lines
8.8 KiB
Python

# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (C) 2019, Raspberry Pi Ltd
# Copyright (C) 2022, Paul Elder <paul.elder@ideasonboard.com>
#
# ALSC module for tuning Raspberry Pi
from .lsc import LSC
import libtuning as lt
import libtuning.utils as utils
from numbers import Number
import numpy as np
import logging
logger = logging.getLogger(__name__)
class ALSCRaspberryPi(LSC):
# Override the type name so that the parser can match the entry in the
# config file.
type = 'alsc'
hr_name = 'ALSC (Raspberry Pi)'
out_name = 'rpi.alsc'
compatible = ['raspberrypi']
def __init__(self, *,
do_color: lt.Param,
luminance_strength: lt.Param,
**kwargs):
super().__init__(**kwargs)
self.do_color = do_color
self.luminance_strength = luminance_strength
self.output_range = (0, 3.999)
def validate_config(self, config: dict) -> bool:
if self not in config:
logger.error(f'{self.type} not in config')
return False
valid = True
conf = config[self]
lum_key = self.luminance_strength.name
color_key = self.do_color.name
if lum_key not in conf and self.luminance_strength.required:
logger.error(f'{lum_key} is not in config')
valid = False
if lum_key in conf and (conf[lum_key] < 0 or conf[lum_key] > 1):
logger.warning(f'{lum_key} is not in range [0, 1]; defaulting to 0.5')
if color_key not in conf and self.do_color.required:
logger.error(f'{color_key} is not in config')
valid = False
return valid
# @return Image color temperature, flattened array of red calibration table
# (containing {sector size} elements), flattened array of blue
# calibration table, flattened array of green calibration
# table
def _do_single_alsc(self, image: lt.Image, do_alsc_colour: bool):
average_green = np.mean((image.channels[lt.Color.GR:lt.Color.GB + 1]), axis=0)
cg, g = self._lsc_single_channel(average_green, image)
if not do_alsc_colour:
return image.color, None, None, cg.flatten()
cr, _ = self._lsc_single_channel(image.channels[lt.Color.R], image, g)
cb, _ = self._lsc_single_channel(image.channels[lt.Color.B], image, g)
# \todo implement debug
return image.color, cr.flatten(), cb.flatten(), cg.flatten()
# @return Red shading table, Blue shading table, Green shading table,
# number of images processed
def _do_all_alsc(self, images: list, do_alsc_colour: bool, general_conf: dict) -> (list, list, list, Number, int):
# List of colour temperatures
list_col = []
# Associated calibration tables
list_cr = []
list_cb = []
list_cg = []
count = 0
for image in self._enumerate_lsc_images(images):
col, cr, cb, cg = self._do_single_alsc(image, do_alsc_colour)
list_col.append(col)
list_cr.append(cr)
list_cb.append(cb)
list_cg.append(cg)
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_cg = np.array(list_cg)
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 unused)
# Average all values for luminance shading and return one table for all temperatures
lum_lut = list(np.round(np.mean(list_cg, axis=0), 3))
if not do_alsc_colour:
return None, None, 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 = np.round(np.mean(list_cr[indices], axis=0), 3)
t_b = np.round(np.mean(list_cb[indices], axis=0), 3)
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, 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 _get_sigma(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, 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.get_value(conf)
# \todo I have no idea where this input parameter is used
luminance_strength = self.luminance_strength.get_value(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._do_all_alsc(images, do_alsc_colour, general_conf)
# \todo Handle the second green lut
cal_cr_list, cal_cb_list, luminance_lut, count = alsc_out
if not do_alsc_colour:
output['luminance_lut'] = luminance_lut
output['n_iter'] = 0
return output
output['calibrations_Cr'] = cal_cr_list
output['calibrations_Cb'] = cal_cb_list
output['luminance_lut'] = luminance_lut
# 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
logger.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._get_sigma(cal_cr_list, cal_cb_list)
output['sigma'] = np.round(sigma_r, 5)
output['sigma_Cb'] = np.round(sigma_b, 5)
return output