Implement background option to converter

rgb565_converter/converter.py

@@ -2,9 +2,16 @@
 
 import argparse
 import os
+from typing import Tuple
+
 from PIL import Image
 from enum import Enum
 
+def hex2rgb(value: str) -> Tuple[int, int, int]:
+    # value is "#5c5c5c" for example
+    value = value.lstrip('#')
+    return tuple(int(value[i:i+2], 16) for i in (0, 2, 4))
+
 class Mode(Enum):
     CPP = ".cpp"
     PNG = ".png"
@@ -52,7 +59,9 @@ def main():
         "-s",
         "--swap",
         dest="swap",
-        help="Swap bytes for 16-bit words."
+        help="Swap bytes for 16-bit words.",
+        default=False,
+        type=bool
     )
     parser.add_argument(
         "-n",
@@ -76,6 +85,13 @@ def main():
         default=None,
         type=str
     )
+    parser.add_argument(
+        "--background",
+        dest="background",
+        help="Replace transparency with a background color.",
+        default=None,
+        type=str
+    )
     args = parser.parse_args()
 
     h_template = DEFAULT_H_TEMPLATE
@@ -126,28 +142,30 @@ def main():
     if mode == Mode.PNG:
         convert_rgb565_to_png(args.input_file, args.output_file, args.swap)
     else:
-        convert_png_to_rgb565(args.input_file, args.output_file, args.swap, args.namespace, cpp_template, h_template)
+        convert_png_to_rgb565(args.input_file, args.output_file, args.swap, args.namespace, args.background, cpp_template, h_template)
 
-def convert_png_to_rgb565(input_file: str, output_file: str, swap: bool, namespace: str, cpp_template: str = DEFAULT_CPP_TEMPLATE, h_template: str = DEFAULT_H_TEMPLATE):
+def convert_png_to_rgb565(input_file: str, output_file: str, swap: bool, namespace: str, background: str | None, cpp_template: str = DEFAULT_CPP_TEMPLATE, h_template: str = DEFAULT_H_TEMPLATE):
     name = os.path.basename(output_file).rsplit('.', 1)[0]
     png = Image.open(input_file)
     width, height = png.size
 
     max_line_width = min(width, 64)
 
-    # iterate over the pixels
-    image = png.getdata()
     image_content = ""
-    for i, pixel in enumerate(image):
-        r = (pixel[0] >> 3) & 0x1F
-        g = (pixel[1] >> 2) & 0x3F
-        b = (pixel[2] >> 3) & 0x1F
-        rgb = r << 11 | g << 5 | b
-
-        if swap:
-            rgb = ((rgb & 0xFF) << 8) | ((rgb & 0xFF00) >> 8)
-
-        image_content += f"0x{rgb:04X}" + (",\n    " if (i % max_line_width == max_line_width-1) else ",")
+    for y in range(height):
+        for x in range(width):
+            pixel = png.getpixel((x, y))
+            if background is not None and pixel[3] == 0:
+                pixel = hex2rgb(background)
+            r = (pixel[0] >> 3) & 0x1F
+            g = (pixel[1] >> 2) & 0x3F
+            b = (pixel[2] >> 3) & 0x1F
+            rgb = r << 11 | g << 5 | b
+
+            if swap:
+                rgb = ((rgb & 0xFF) << 8) | ((rgb & 0xFF00) >> 8)
+
+            image_content += f"0x{rgb:04X}" + (",\n    " if (x % max_line_width == max_line_width-1) else ",")
 
     if image_content.endswith("\n    "):
         image_content = image_content[:-5]

setup.py

@@ -2,7 +2,7 @@
 
 setup(
     name='rgb565-converter',
-    version='1.3.0',
+    version='1.3.1',
     description='Convert a file from png to rgb565 (cpp) and vice versa.',
     url='https://github.com/CommanderRedYT/rgb565-converter',
     author='CommanderRedYT',
@@ -13,7 +13,7 @@
             'rgb565-converter=rgb565_converter.converter:main',
         ],
     },
-    python_requires='>=3.6',
+    python_requires='>=3.7',
     long_description=open('README.md').read(),
     long_description_content_type='text/markdown',
     install_requires=[

tests/test_converter.py

@@ -6,10 +6,17 @@
 
 TEST_DIRECTORY='tests'
 TEST_INPUT_FILE=f'{TEST_DIRECTORY}/input_info.png'
+
 TEST_OUTPUT_CPP_FILE=f'{TEST_DIRECTORY}/output_info.cpp'
 TEST_OUTPUT_H_FILE=f'{TEST_DIRECTORY}/output_info.h'
 TEST_OUTPUT_PNG_FILE=f'{TEST_DIRECTORY}/output_info_double.png'
 
+TEST_INPUT_GREY_PNG_FILE=f'{TEST_DIRECTORY}/back.png'
+TEST_OUTPUT_GREY_CPP_FILE=f'{TEST_DIRECTORY}/output_grey.cpp'
+TEST_OUTPUT_GREY_H_FILE=f'{TEST_DIRECTORY}/output_grey.h'
+TEST_OUTPUT_GREY_PNG_FILE=f'{TEST_DIRECTORY}/output_grey_double.png'
+TEST_COMPARE_GREY_PNG_FILE=f'{TEST_DIRECTORY}/test_grey_back.png'
+
 TEST_CUSTOM_CPP_TEMPLATE=f'{TEST_DIRECTORY}/custom_cpp_template.txt'
 TEST_CUSTOM_H_TEMPLATE=f'{TEST_DIRECTORY}/custom_h_template.txt'
 
@@ -30,12 +37,22 @@ def tearDownClass(cls):
         if os.path.exists(TEST_OUTPUT_PNG_FILE):
             os.remove(TEST_OUTPUT_PNG_FILE)
 
+        if os.path.exists(TEST_OUTPUT_GREY_CPP_FILE):
+            os.remove(TEST_OUTPUT_GREY_CPP_FILE)
+
+        if os.path.exists(TEST_OUTPUT_GREY_H_FILE):
+            os.remove(TEST_OUTPUT_GREY_H_FILE)
+
+        if os.path.exists(TEST_OUTPUT_GREY_PNG_FILE):
+            os.remove(TEST_OUTPUT_GREY_PNG_FILE)
+
     def test_converter(self):
         args = {
             'input_file': TEST_INPUT_FILE,
             'output_file': TEST_OUTPUT_CPP_FILE,
             'swap': False,
-            'namespace': 'foobar'
+            'namespace': 'foobar',
+            'background': None,
         }
 
         convert_png_to_rgb565(**args)
@@ -104,7 +121,8 @@ def test_converter_custom_template(self):
             'swap': False,
             'namespace': 'foobar',
             'cpp_template': cpp_template,
-            'h_template': h_template
+            'h_template': h_template,
+            'background': None,
         }
 
         convert_png_to_rgb565(**args)
@@ -154,5 +172,33 @@ def test_converter_custom_template(self):
         with open(TEST_INPUT_FILE, 'rb') as f1, open(TEST_OUTPUT_PNG_FILE, 'rb') as f2:
             self.assertEqual(f1.read(), f2.read())
 
+    def test_converter_with_grey_mode(self):
+        args = {
+            'input_file': TEST_INPUT_GREY_PNG_FILE,
+            'output_file': TEST_OUTPUT_GREY_CPP_FILE,
+            'swap': False,
+            'namespace': 'foobar',
+            'background': '#5c5c5c'
+        }
+
+        convert_png_to_rgb565(**args)
+
+        # check if files exist
+        self.assertTrue(os.path.exists(TEST_OUTPUT_GREY_CPP_FILE))
+        self.assertTrue(os.path.exists(TEST_OUTPUT_GREY_H_FILE))
+
+        # convert back to png
+        args = {
+            'input_file': TEST_OUTPUT_GREY_CPP_FILE,
+            'output_file': TEST_OUTPUT_GREY_PNG_FILE,
+            'swap': False
+        }
+
+        convert_rgb565_to_png(**args)
+
+        # check if both png files are binary equal
+        with open(TEST_COMPARE_GREY_PNG_FILE, 'rb') as f1, open(TEST_OUTPUT_GREY_PNG_FILE, 'rb') as f2:
+            self.assertEqual(f1.read(), f2.read())
+
 if __name__ == '__main__':
     unittest.main()