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Upload preprocess.py
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import numpy as np
import cv2
# This function is modified from the following code snippet:
# https://github.com/StanislasBertrand/RetinaFace-tf2/blob/5f68ce8130889384cb8aca937a270cea4ef2d020/retinaface.py#L49-L74
def resize_image(img, scales, allow_upscaling):
img_h, img_w = img.shape[0:2]
target_size = scales[0]
max_size = scales[1]
if img_w > img_h:
im_size_min, im_size_max = img_h, img_w
else:
im_size_min, im_size_max = img_w, img_h
im_scale = target_size / float(im_size_min)
if not allow_upscaling:
im_scale = min(1.0, im_scale)
if np.round(im_scale * im_size_max) > max_size:
im_scale = max_size / float(im_size_max)
if im_scale != 1.0:
img = cv2.resize(
img,
None,
None,
fx=im_scale,
fy=im_scale,
interpolation=cv2.INTER_LINEAR
)
return img, im_scale
# This function is modified from the following code snippet:
# https://github.com/StanislasBertrand/RetinaFace-tf2/blob/5f68ce8130889384cb8aca937a270cea4ef2d020/retinaface.py#L76-L96
def preprocess_image(img, allow_upscaling):
pixel_means = np.array([0.0, 0.0, 0.0], dtype=np.float32)
pixel_stds = np.array([1.0, 1.0, 1.0], dtype=np.float32)
pixel_scale = float(1.0)
scales = [1024, 1980]
img, im_scale = resize_image(img, scales, allow_upscaling)
img = img.astype(np.float32)
im_tensor = np.zeros((1, img.shape[0], img.shape[1], img.shape[2]), dtype=np.float32)
# Make image scaling + BGR2RGB conversion + transpose (N,H,W,C) to (N,C,H,W)
for i in range(3):
im_tensor[0, :, :, i] = (img[:, :, 2 - i] / pixel_scale - pixel_means[2 - i]) / pixel_stds[2 - i]
return im_tensor, img.shape[0:2], im_scale