Sebastian Wick swick
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| #!/bin/bash | |
| # | |
| # Steam installer for Debian wheezy (32- and 64-bit) | |
| # | |
| # Place into empty directory and run. | |
| # | |
| download() { | |
| local url="$1" | |
| local filename="$(basename "$url")" |
pthom
/ overlay_alpha_image_precise.py
Last active
June 30, 2023 10:16
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| import numpy as np | |
| import cv2 | |
| def overlay_alpha_image_lazy(background_rgb, overlay_rgba, alpha): | |
| # cf https://en.wikipedia.org/wiki/Alpha_compositing#Alpha_blending | |
| # If the destination background is opaque, then | |
| # out_rgb = overlay_rgb * overlay_alpha + background_rgb * (1 - overlay_alpha) | |
| overlay_alpha = overlay_rgba[: , : , 3].astype(np.float) / 255. * alpha | |
| overlay_alpha_3 = np.dstack((overlay_alpha, overlay_alpha, overlay_alpha)) | |
| overlay_rgb = overlay_rgba[: , : , : 3].astype(np.float) |