Unify DHGRScreen implementations

convert.py

@@ -62,11 +62,7 @@ def main():
     args = parser.parse_args()
 
     palette = palette_py.PALETTES[args.palette]()
-    if args.palette == "ntsc":
-        # TODO: palette depth should be controlled by Palette not Screen
-        screen = screen_py.DHGR560NTSCScreen(palette)
-    else:
-        screen = screen_py.DHGR560Screen(palette)
+    screen = screen_py.DHGRScreen(palette)
     if args.lookahead < 1:
         parser.error('--lookahead must be at least 1')
     lookahead = args.lookahead
@@ -92,10 +88,8 @@ def main():
     # Show output image by rendering in target palette
     output_palette_name = args.show_palette or args.palette
     output_palette = palette_py.PALETTES[output_palette_name]()
-    if output_palette_name == "ntsc":
-        output_screen = screen_py.DHGR560NTSCScreen(output_palette)
-    else:
-        output_screen = screen_py.DHGR560Screen(output_palette)
+    output_screen = screen_py.DHGRScreen(output_palette)
+    # TODO: if output_palette_name == "ntsc" show bitmap_to_image_ntsc instead
     output_rgb = output_screen.bitmap_to_image_rgb(bitmap)
     out_image = Image.fromarray(image_py.linear_to_srgb(output_rgb).astype(
         np.uint8))

ntsc_colours.py

@@ -31,7 +31,7 @@ def main():
             bitmap[0, j:j + 8] = bits8
 
             # bitmap_to_ntsc produces 3 output pixels for each DHGR input
-            ntsc = s.bitmap_to_ntsc(bitmap)
+            ntsc = s.bitmap_to_image_ntsc(bitmap)
             last_colour = ntsc[0, 3 * (j + 8) - 1, :]
             colours[(bits, j - ntsc_shift)] = last_colour
             unique.add(tuple(last_colour))

palette.py

@@ -10,7 +10,6 @@ class Palette:
     SRGB = None
     RGB = {}
     CAM16UCS = {}
-    # DOTS_TO_INDEX = {}
 
     # How many successive screen pixels are used to compute output pixel 
     # palette index.
@@ -26,18 +25,6 @@ class Palette:
                 self.CAM16UCS[k] = colour.convert(
                     v / 255, "sRGB", "CAM16UCS").astype(np.float32)
 
-        # # Maps palette values to screen dots.  Note that these are the same as
-        # # the binary index values in reverse order.
-        # _DOTS = {}
-        # for i in range(1 << self.PALETTE_DEPTH):
-        #     _DOTS[i] = tuple(
-        #         bool(i & (1 << j)) for j in range(self.PALETTE_DEPTH))
-        #
-        # # Reverse mapping from screen dots to palette index.
-        # self.DOTS_TO_INDEX = {}
-        # for k, v in _DOTS.items():
-        #     self.DOTS_TO_INDEX[v] = k
-
     def pixels_to_idx(self, pixels: np.array) -> int:
         return np.packbits(
             # numpy uses big-endian representation which is the opposite

screen.py

@@ -52,29 +52,7 @@ class DHGRScreen:
     def bitmap_to_image_rgb(self, bitmap: np.ndarray) -> np.ndarray:
         """Convert our 2-bit bitmap image into a RGB image.
 
-        Colour at every pixel is determined by the value of a 4-bit sliding
-        window indexed by x % 4, which gives the index into our 16-colour RGB
-        palette.
-        """
-        image_rgb = np.empty((self.Y_RES, self.X_RES, 3),
-                             dtype=np.uint8)
-        for y in range(self.Y_RES):
-            pixel = [False, False, False, False]
-            for x in range(self.X_RES):
-                pixel[x % 4] = bitmap[y, x]
-                dots = self.palette.DOTS_TO_INDEX[tuple(pixel)]
-                image_rgb[y, x, :] = self.palette.RGB[dots]
-        return image_rgb
-
-
-# TODO: refactor to share implementation with DHGR560Screen
-class DHGR560NTSCScreen(DHGRScreen):
-    """DHGR screen including colour fringing and 8 pixel chroma bleed."""
-
-    # TODO: unify with parent
-    def bitmap_to_image_rgb(self, bitmap: np.ndarray) -> np.ndarray:
-        """Convert our 2-bit bitmap image into a RGB image.
-
+        XXX
         Colour at every pixel is determined by the value of a 8-bit sliding
         window indexed by x % 4, which gives the index into our 256-colour RGB
         palette.
@@ -83,8 +61,8 @@ class DHGR560NTSCScreen(DHGRScreen):
         for y in range(self.Y_RES):
             pixels = [False] * self.palette.PALETTE_DEPTH
             for x in range(self.X_RES):
+                # Maintain a sliding window of pixels of width PALETTE_DEPTH
                 pixels = pixels[1:] + [bitmap[y, x]]
-                # dots = self.palette.DOTS_TO_INDEX[tuple(pixel)]
                 image_rgb[y, x, :] = self.palette.RGB[
                     self.palette.pixels_to_idx(
                         np.array(pixels, dtype=bool)), x % 4]
@@ -106,7 +84,7 @@ class DHGR560NTSCScreen(DHGRScreen):
 
         return 1 if line[pos] else 0
 
-    def bitmap_to_ntsc(self, bitmap: np.ndarray) -> np.ndarray:
+    def bitmap_to_image_ntsc(self, bitmap: np.ndarray) -> np.ndarray:
         y_width = 12
         u_width = 24
         v_width = 24