Apple-2-SW/ii-pix
1
0
Fork 0
mirror of https://github.com/KrisKennaway/ii-pix.git synced 2024-11-07 22:06:34 +00:00
Code Issues Projects Releases Wiki Activity

Support arbitrary gamma correction of input image

Browse Source
This commit is contained in:
kris 2021-07-19 09:57:26 +01:00
parent 7a3adea025
commit 70074a2942
2 changed files with 15 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
convert.py
View File

@ -65,6 +65,10 @@ def main():
parser.add_argument(
'--verbose', action=argparse.BooleanOptionalAction,
default=False, help="Show progress during conversion")
parser.add_argument(
'--gamma_correct', type=float, default=2.4,
help='Gamma-correct image by this value (default: 2.4)'
)
args = parser.parse_args()
palette = palette_py.PALETTES[args.palette]()
@ -88,7 +92,9 @@ def main():
image_py.resize(image, screen.NATIVE_X_RES, screen.NATIVE_Y_RES * 2,
srgb_output=True).show()
resized = np.array(image_py.resize(image, screen.X_RES,
screen.Y_RES)).astype(np.float32)
screen.Y_RES,
gamma=args.gamma_correct)).astype(
np.float32)
# convert from sRGB1-linear to CAM02UCS perceptually uniform colour space
cam16ucs = colour.convert(

13
image.py
View File

@ -13,8 +13,8 @@ def linear_to_srgb_array(a: np.ndarray, gamma=2.4) -> np.ndarray:
0.055)
def srgb_to_linear(im: np.ndarray) -> np.ndarray:
rgb_linear = srgb_to_linear_array(im / 255.0, gamma=2.4)
def srgb_to_linear(im: np.ndarray, gamma=2.4) -> np.ndarray:
rgb_linear = srgb_to_linear_array(im / 255.0, gamma=gamma)
return (np.clip(rgb_linear, 0.0, 1.0) * 255).astype(np.float32)
@ -32,13 +32,16 @@ def open(filename: str) -> np.ndarray:
return im
def resize(image: Image, x_res, y_res, srgb_output: bool = False) -> Image:
def resize(
image: Image, x_res, y_res, gamma: float = 2.4,
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(image)).astype(np.uint8)
linear = srgb_to_linear(np.asarray(image), gamma=gamma).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))
linear_to_srgb(np.array(res, dtype=np.float32), gamma=gamma).astype(
np.uint8))
else:
return res