raygeo.image.transparency

Functions

make_transparent_by_brightness()

make_transparent_by_brightness(
    rgba: numpy.NDArray[numpy.uint8],
    width: int,
    height: int,
    stride: int,
    threshold: int = 250,
) -> None

Clear alpha for bright pixels in an ARGB32 buffer (in-place).

Pixels with BT.601-weighted brightness >= threshold have their alpha channel set to 0.

Parameter	Type	Description
rgba	numpy.NDArray[numpy.uint8]	Flattened uint8 buffer of shape (stride * height * 4,).
width	int	Image width in pixels.
height	int	Image height in pixels.
stride	int	Row stride in pixels (may be larger than width).
threshold	int = 250	Brightness threshold (0-255).
Returns	None
Complexity		O(w*h)

make_transparent_except_color()

make_transparent_except_color(
    rgba: numpy.NDArray[numpy.uint8],
    width: int,
    height: int,
    stride: int,
    target_r: int,
    target_g: int,
    target_b: int,
) -> None

Clear alpha for non-matching pixels in an ARGB32 buffer (in-place).

Pixels that do not match the target RGB color have their alpha channel set to 0.

Parameter	Type	Description
rgba	numpy.NDArray[numpy.uint8]	Flattened uint8 buffer of shape (stride * height * 4,).
width	int	Image width in pixels.
height	int	Image height in pixels.
stride	int	Row stride in pixels.
target_r	int	Target red channel value (0-255).
target_g	int	Target green channel value (0-255).
target_b	int	Target blue channel value (0-255).
Returns	None
Complexity		O(w*h)