utils: rkisp1: Add script to parse RPi lens shading tables

Add a python script to parse the lens shading tables from the
RaspberryPi json tuning file.

Example invocation:
./utils/rkisp1/rkisp1_lsc_rpi_to_libcamera.py \
	-f src/ipa/raspberrypi/data/imx219.json \
	-a src/ipa/rkisp1/data/imx219.yaml -t 1000

The script overrides the existing "LensShadingCorrection" section
in the output .yaml configuration file.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>

1 files changed, 139 insertions, 0 deletions

diff --git a/utils/rkisp1/rkisp1_lsc_rpi_to_libcamera.py b/utils/rkisp1/rkisp1_lsc_rpi_to_libcamera.py
new file mode 100755
index 00000000..e86a88ad
--- /dev/null
+++ b/utils/rkisp1/rkisp1_lsc_rpi_to_libcamera.py
@@ -0,0 +1,139 @@
+#!/usr/bin/env python3
+
+import argparse
+import json
+import numpy as np
+import scipy.ndimage
+import sys
+import yaml
+
+
+def update_yaml_config(config, reds, green, blues):
+    with open(config, 'r') as config:
+        data = yaml.safe_load(config)
+
+        xy_sizes = [0.0625, 0.0625, 0.0625,
+                    0.0625, 0.0625, 0.0625, 0.0625, 0.0625]
+
+        lsc_config = {}
+        lsc_config['x-size'] = []
+        lsc_config['y-size'] = []
+        for size in xy_sizes:
+            lsc_config['x-size'].append(size)
+            lsc_config['y-size'].append(size)
+        lsc_config['sets'] = []
+
+        for temperature in reds.keys():
+            red_table = reds[temperature].flatten()
+            blue_table = blues[temperature].flatten()
+
+            ct_set = {}
+            ct_set['ct'] = temperature
+            ct_set['r'] = []
+            ct_set['gr'] = []
+            ct_set['gb'] = []
+            ct_set['b'] = []
+
+            for f in red_table:
+                i = round(f * 1024)
+                ct_set['r'].append(i)
+
+            for f in green:
+                i = round(f * 1024)
+
+                ct_set['gr'].append(i)
+                ct_set['gb'].append(i)
+
+            for f in blue_table:
+                i = round(f * 1024)
+
+                ct_set['b'].append(i)
+
+            lsc_config['sets'].append(ct_set)
+
+        lsc = {'LensShadingCorrection': lsc_config}
+
+        # Remove any existing LensShadingCorrection section
+        algos = data['algorithms']
+        for algo in algos:
+            for k in algo.keys():
+                if k == 'LensShadingCorrection':
+                    algos.remove(algo)
+                    break
+
+        algos.append(lsc)
+        print(data)
+        return data
+
+
+def sort_by_temperature(calibrations):
+    data = {}
+    for entry in calibrations:
+        temp = entry['ct']
+        table = np.array(entry['table']).reshape(12, 16)
+
+        data[temp] = table
+
+    return data
+
+
+def parse_lsc_data(filename):
+    with open(filename, 'r') as tuning_file:
+        for algo in json.load(tuning_file)['algorithms']:
+            for (k, v) in algo.items():
+                if k == 'rpi.alsc':
+                    return v
+
+    raise Exception("Cannot find LSC tuning data in file " + filename)
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('-f', '--file', required=True,
+                        help='Tuning file to parse')
+    parser.add_argument('-t', '--temperature', help='Color temperature')
+    # todo: Do not make this mandatory and default to stdio
+    parser.add_argument('-a', '--append', required=True,
+                        help='RkISP configuration file to append LSC tables to')
+
+    args = parser.parse_args()
+
+    lsc_data = parse_lsc_data(args.file)
+
+    luminance_strength = lsc_data['luminance_strength']
+    luma = np.array(lsc_data['luminance_lut']).reshape(12, 16)
+    green = (luma - 1) * luminance_strength + 1
+
+    cr_data = sort_by_temperature(lsc_data['calibrations_Cr'])
+    cb_data = sort_by_temperature(lsc_data['calibrations_Cb'])
+
+    reds = {}
+    blues = {}
+
+    for temperature in cr_data.keys():
+        cr = cr_data[temperature]
+        cb = cb_data[temperature]
+
+        red = cr * green
+        red = scipy.ndimage.zoom(red, (17 / 12, 17 / 16))
+        red /= red.min()
+
+        blue = cb * green
+        blue = scipy.ndimage.zoom(blue, (17 / 12, 17 / 16))
+        blue /= blue.min()
+
+        reds[temperature] = red
+        blues[temperature] = blue
+
+    green = scipy.ndimage.zoom(green, (17 / 12, 17 / 16))
+    green /= green.min()
+
+    new_config = update_yaml_config(args.append, reds, green.flatten(), blues)
+    with open(args.append, 'w') as config:
+        yaml.safe_dump(new_config, config)
+
+    return 0
+
+
+if __name__ == '__main__':
+    sys.exit(main())