factor common code out

More helpers & more files.

1 files changed, 52 insertions, 0 deletions

diff --git a/bin/shift.py b/bin/shift.py
new file mode 100644
index 0000000..8dfd76a
--- /dev/null
+++ b/bin/shift.py
@@ -0,0 +1,52 @@
+# Copyright 2016 (c) Egor Tensin <Egor.Tensin@gmail.com>
+# This file is part of the "Simple image filters" project.
+# For details, see https://github.com/egor-tensin/filters.
+# Distributed under the MIT License.
+
+import argparse
+import sys
+
+from .utils import cmd_line, image
+from filters.convolution import convolve
+from filters.kernel.shift import Direction
+
+DEFAULT_DIRECTION = Direction.SOUTH_EAST
+DEFAULT_DISTANCE = 1
+
+def _main_shift(
+        img_path, direction=DEFAULT_DIRECTION, distance=DEFAULT_DISTANCE,
+        output_path=None):
+
+    img = image.load_grayscale(img_path)
+    kernel = direction.gen_kernel(distance)
+    output = convolve(img, kernel)
+    if output_path is None:
+        image.show(output)
+    else:
+        image.save(output_path, output)
+
+def _parse_direction(s):
+    try:
+        return Direction(s)
+    except ValueError:
+        raise argparse.ArgumentTypeError('invalid direction: ' + s)
+
+def _parse_args(args=sys.argv):
+    parser = argparse.ArgumentParser()
+    parser.add_argument('img_path')
+    parser.add_argument('--output', '-o',
+                        dest='output_path', default=None)
+    parser.add_argument('--direction', '-d',
+                        type=_parse_direction,
+                        choices=Direction,
+                        default=DEFAULT_DIRECTION)
+    parser.add_argument('--distance', '-n',
+                        type=cmd_line.parse_non_negative_integer,
+                        default=DEFAULT_DISTANCE)
+    return parser.parse_args(args[1:])
+
+def _main(args=sys.argv):
+    _main_shift(**vars(_parse_args(args)))
+
+if __name__ == '__main__':
+    _main()