1 files changed, 187 insertions, 0 deletions
diff --git a/utils/rkisp1/lsc_parse_android_config.py b/utils/rkisp1/lsc_parse_android_config.py
new file mode 100755
index 00000000..a7c2c160
--- /dev/null
+++ b/utils/rkisp1/lsc_parse_android_config.py
@@ -0,0 +1,187 @@
+#!/usr/bin/env python
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2023, Jacopo Mondi - Ideas on Board Oy
+#
+# Parse Android .xml configuration file and extract the LSC tables.
+#
+# Print to standard output a "LensShadingCorrection" section, understandable by
+# libcamera LSC algorithm, that can be pasted to the sensor configuration file.
+
+import argparse
+import string
+import sys
+import re
+import xml.etree.ElementTree as et
+
+
+def sanitize(name):
+    return re.sub(r"[\n\t\s]*", "", name)
+
+
+def split_table(table):
+    values = ""
+    for v in table.text.strip(' ').split():
+        values += v.strip('[').strip(']') + ", "
+    return values
+
+
+def print_cell(cell):
+    lsc_template = string.Template('''        #${name} - ${illuminant}
+        - ct: ${ct}
+          resolution: ${res}
+          r: [${red}]
+          gr: [${greenr}]
+          gb: [${greenb}]
+          b: [${blue}]''')
+
+    illuminant = cell.find("illumination")
+    ct = illuminant_to_ct(illuminant)
+
+    template_dict = {
+        'name': sanitize(cell.find("name").text),
+        'illuminant': sanitize(illuminant.text),
+        'ct': ct,
+        'res': sanitize(cell.find("resolution").text)
+    }
+
+    red_table = cell.find("LSC_SAMPLES_red")
+    greenr_table = cell.find("LSC_SAMPLES_greenR")
+    greenb_table = cell.find("LSC_SAMPLES_greenB")
+    blue_table = cell.find("LSC_SAMPLES_blue")
+
+    if red_table is None or greenr_table is None or greenb_table is None or blue_table is None:
+        return
+
+    template_dict['red'] = split_table(red_table)
+    template_dict['greenr'] = split_table(greenr_table)
+    template_dict['greenb'] = split_table(greenb_table)
+    template_dict['blue'] = split_table(blue_table)
+
+    return lsc_template.substitute(template_dict)
+
+
+def illuminant_to_ct(illuminant):
+    # Standard CIE Illiminants to Color Temperature in Kelvin
+    # https://en.wikipedia.org/wiki/Standard_illuminant
+    #
+    # Not included (and then ignored when parsing the configuration file):
+    # - "Horizon" == D50 == 5003
+    # - "BW" == ?
+    # - "PREFLASH" == ?
+    illuminants_dict = {
+        'A': 2856,
+        'D50': 5003,
+        'D65': 6504,
+        'D75': 7504,
+        'F11_TL84': 4000,
+        'F2_CWF': 4230,
+    }
+
+    ill_key = sanitize(illuminant.text)
+    try:
+        ct = illuminants_dict[ill_key]
+    except KeyError:
+        return None
+
+    return ct
+
+
+# Make sure the cell is well formed and return it
+def filter_cells(cell, res, lsc_cells):
+    name = cell.find("name")
+    resolution = cell.find("resolution")
+    illumination = cell.find("illumination")
+    vignetting = cell.find("vignetting")
+
+    if name is None or resolution is None or \
+       illumination is None or vignetting is None:
+        return
+
+    # Skip tables for smaller sensor resolutions
+    if res != sanitize(resolution.text):
+        return
+
+    # Skip tables for which we don't know how to translate the illuminant value
+    ct = illuminant_to_ct(illumination)
+    if ct is None:
+        return
+
+    # Only pick tables with vignetting == 70
+    if sanitize(vignetting.text) != "[70]":
+        return
+
+    lsc_cells.append(cell)
+
+
+# Get the "LSC" node
+def find_lsc_table(root):
+    sensor = root.find('sensor')
+    if sensor is None:
+        print("Failed to find \"sensor\" node in config file")
+        raise Exception
+
+    lsc = sensor.find('LSC')
+    if lsc is None:
+        print("Filed to find \"LSC\" node in config file")
+        raise Exception
+
+    return lsc
+
+# libcamera LSC algorithm only operates on a single resolution.
+# Find the largest sensor mode among the ones reported in the LSC tables
+
+
+def parse_max_res(cells):
+    max_res = ""
+    max_size = 0
+
+    for cell in cells:
+        resolution = sanitize(cell.find("resolution").text)
+        [w, h] = resolution.split('x')
+
+        area = int(w) * int(h)
+        if area > max_size:
+            max_res = resolution
+
+    return max_res
+
+
+def main(argv):
+    # Parse command line arguments.
+    parser = argparse.ArgumentParser(
+        description='Parse Android camera configuration file to extract LSC tables')
+    parser.add_argument('--file', '-f', required=True,
+                        help='Path to the Android .xml configuration file')
+    args = parser.parse_args(argv[1:])
+
+    root = et.parse(args.file).getroot()
+    try:
+        lsc_node = find_lsc_table(root)
+    except Exception:
+        return 1
+
+    cells = lsc_node.findall("cell")
+
+    max_res = parse_max_res(cells)
+    if max_res == "":
+        return
+
+    lsc_cells = []
+    for cell in cells:
+        filter_cells(cell, max_res, lsc_cells)
+
+    lsc_section = '''  - LensShadingCorrection:
+      x-size: [ 0.0625, 0.0625, 0.0625, 0.0625, 0.0625, 0.0625, 0.0625, 0.0625 ]
+      y-size: [ 0.0625, 0.0625, 0.0625, 0.0625, 0.0625, 0.0625, 0.0625, 0.0625 ]
+      sets:
+'''
+
+    for cell in lsc_cells:
+        lsc_section += print_cell(cell) + "\n"
+
+    print(lsc_section)
+
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv))