Show output as 560x384 regardless of input size

convert.py

@@ -59,15 +59,18 @@ def main():
         screen = screen_py.DHGR140Screen(palette)
         lookahead = 0
 
-    image = image_py.open(screen.X_RES, screen.Y_RES, args.input)
+    image = image_py.open(args.input)
+    # TODO: better performance with malloc'ed array?
+    resized = np.array(
+        image_py.resize(image, screen.X_RES, screen.Y_RES)).astype(np.float32)
     if args.show_input:
-        Image.fromarray(image.astype(np.uint8)).show()
+        Image.fromarray(resized.astype(np.uint8)).show()
 
     dither = dither_pattern.PATTERNS[args.dither]()
 
     start = time.time()
     output_4bit, output_rgb = dither_pyx.dither_image(
-        screen, image, dither, lookahead)
+        screen, resized, dither, lookahead)
     print(time.time() - start)
     screen.pack(output_4bit)
 
@@ -76,7 +79,7 @@ def main():
     outfile = os.path.join(os.path.splitext(args.output)[0] + ".png")
     out_image.save(outfile, "PNG")
     if args.show_output:
-        out_image.show()
+        image_py.resize(out_image, 560, 384, srgb_output=True).show()
 
     with open(args.output, "wb") as f:
         f.write(bytes(screen.main))

image.py

@@ -21,17 +21,22 @@ def linear_to_srgb(im: np.ndarray) -> np.ndarray:
     return (np.clip(srgb, 0.0, 1.0) * 255).astype(np.float32)
 
 
-def open(x_res:int, y_res:int, filename: str) -> np.ndarray:
+def open(filename: str) -> np.ndarray:
     im = Image.open(filename)
     # TODO: convert to sRGB colour profile explicitly, in case it has some other
     #  profile already.
     if im.mode != "RGB":
         im = im.convert("RGB")
+    return im
 
+
+def resize(image: Image, x_res, y_res, srgb_output: bool = False) -> Image:
     # Convert to linear RGB before rescaling so that colour interpolation is
     # in linear space
-    linear = srgb_to_linear(np.asarray(im)).astype(np.uint8)
-    rescaled = Image.fromarray(linear).resize((x_res, y_res), Image.LANCZOS)
-    # TODO: better performance with malloc'ed array?
-    return np.array(rescaled).astype(np.float32)
-
+    linear = srgb_to_linear(np.asarray(image)).astype(np.uint8)
+    res = Image.fromarray(linear).resize((x_res, y_res), Image.LANCZOS)
+    if srgb_output:
+        return Image.fromarray(
+            linear_to_srgb(np.array(res, dtype=np.float32)).astype(np.uint8))
+    else:
+        return res