faceblur / yolov8.py
mmkuznecov's picture
fixed bug
27ef2bf
import cv2
import numpy as np
import math
class YOLOv8Face:
def __init__(self, path, conf_thres=0.2, iou_thres=0.5):
self.conf_threshold = conf_thres
self.iou_threshold = iou_thres
self.class_names = ['face']
self.num_classes = len(self.class_names)
# Initialize model
self.net = cv2.dnn.readNet(path)
self.input_height = 640
self.input_width = 640
self.reg_max = 16
self.project = np.arange(self.reg_max)
self.strides = (8, 16, 32)
self.feats_hw = [(math.ceil(self.input_height / self.strides[i]), math.ceil(self.input_width / self.strides[i])) for i in range(len(self.strides))]
self.anchors = self.make_anchors(self.feats_hw)
def make_anchors(self, feats_hw, grid_cell_offset=0.5):
"""Generate anchors from features."""
anchor_points = {}
for i, stride in enumerate(self.strides):
h,w = feats_hw[i]
x = np.arange(0, w) + grid_cell_offset # shift x
y = np.arange(0, h) + grid_cell_offset # shift y
sx, sy = np.meshgrid(x, y)
# sy, sx = np.meshgrid(y, x)
anchor_points[stride] = np.stack((sx, sy), axis=-1).reshape(-1, 2)
return anchor_points
def softmax(self, x, axis=1):
x_exp = np.exp(x)
x_sum = np.sum(x_exp, axis=axis, keepdims=True)
s = x_exp / x_sum
return s
def resize_image(self, srcimg, keep_ratio=True):
top, left, newh, neww = 0, 0, self.input_width, self.input_height
if keep_ratio and srcimg.shape[0] != srcimg.shape[1]:
hw_scale = srcimg.shape[0] / srcimg.shape[1]
if hw_scale > 1:
newh, neww = self.input_height, int(self.input_width / hw_scale)
img = cv2.resize(srcimg, (neww, newh), interpolation=cv2.INTER_AREA)
left = int((self.input_width - neww) * 0.5)
img = cv2.copyMakeBorder(img, 0, 0, left, self.input_width - neww - left, cv2.BORDER_CONSTANT,
value=(0, 0, 0)) # add border
else:
newh, neww = int(self.input_height * hw_scale), self.input_width
img = cv2.resize(srcimg, (neww, newh), interpolation=cv2.INTER_AREA)
top = int((self.input_height - newh) * 0.5)
img = cv2.copyMakeBorder(img, top, self.input_height - newh - top, 0, 0, cv2.BORDER_CONSTANT,
value=(0, 0, 0))
else:
img = cv2.resize(srcimg, (self.input_width, self.input_height), interpolation=cv2.INTER_AREA)
return img, newh, neww, top, left
def detect(self, srcimg):
input_img, newh, neww, padh, padw = self.resize_image(cv2.cvtColor(srcimg, cv2.COLOR_BGR2RGB))
scale_h, scale_w = srcimg.shape[0]/newh, srcimg.shape[1]/neww
input_img = input_img.astype(np.float32) / 255.0
blob = cv2.dnn.blobFromImage(input_img)
self.net.setInput(blob)
outputs = self.net.forward(self.net.getUnconnectedOutLayersNames())
det_bboxes, det_conf, det_classid, landmarks = self.post_process(outputs, scale_h, scale_w, padh, padw)
return det_bboxes, det_conf, det_classid, landmarks
def post_process(self, preds, scale_h, scale_w, padh, padw):
bboxes, scores, landmarks = [], [], []
for i, pred in enumerate(preds):
stride = int(self.input_height/pred.shape[2])
pred = pred.transpose((0, 2, 3, 1))
box = pred[..., :self.reg_max * 4]
cls = 1 / (1 + np.exp(-pred[..., self.reg_max * 4:-15])).reshape((-1,1))
kpts = pred[..., -15:].reshape((-1,15)) ### x1,y1,score1, ..., x5,y5,score5
tmp = box.reshape(-1, 4, self.reg_max)
bbox_pred = self.softmax(tmp, axis=-1)
bbox_pred = np.dot(bbox_pred, self.project).reshape((-1,4))
bbox = self.distance2bbox(self.anchors[stride], bbox_pred, max_shape=(self.input_height, self.input_width)) * stride
kpts[:, 0::3] = (kpts[:, 0::3] * 2.0 + (self.anchors[stride][:, 0].reshape((-1,1)) - 0.5)) * stride
kpts[:, 1::3] = (kpts[:, 1::3] * 2.0 + (self.anchors[stride][:, 1].reshape((-1,1)) - 0.5)) * stride
kpts[:, 2::3] = 1 / (1+np.exp(-kpts[:, 2::3]))
bbox -= np.array([[padw, padh, padw, padh]])
bbox *= np.array([[scale_w, scale_h, scale_w, scale_h]])
kpts -= np.tile(np.array([padw, padh, 0]), 5).reshape((1,15))
kpts *= np.tile(np.array([scale_w, scale_h, 1]), 5).reshape((1,15))
bboxes.append(bbox)
scores.append(cls)
landmarks.append(kpts)
bboxes = np.concatenate(bboxes, axis=0)
scores = np.concatenate(scores, axis=0)
landmarks = np.concatenate(landmarks, axis=0)
bboxes_wh = bboxes.copy()
bboxes_wh[:, 2:4] = bboxes[:, 2:4] - bboxes[:, 0:2] # x y w h
classIds = np.argmax(scores, axis=1)
confidences = np.max(scores, axis=1) # max_class_confidence
mask = confidences>self.conf_threshold
bboxes_wh = bboxes_wh[mask]
confidences = confidences[mask]
classIds = classIds[mask]
landmarks = landmarks[mask]
indices = cv2.dnn.NMSBoxes(bboxes_wh.tolist(), confidences.tolist(), self.conf_threshold,
self.iou_threshold)
if len(indices) > 0:
indices = indices.flatten()
mlvl_bboxes = bboxes_wh[indices]
confidences = confidences[indices]
classIds = classIds[indices]
landmarks = landmarks[indices]
return mlvl_bboxes, confidences, classIds, landmarks
else:
print('nothing detect')
return np.array([]), np.array([]), np.array([]), np.array([])
def distance2bbox(self, points, distance, max_shape=None):
x1 = points[:, 0] - distance[:, 0]
y1 = points[:, 1] - distance[:, 1]
x2 = points[:, 0] + distance[:, 2]
y2 = points[:, 1] + distance[:, 3]
if max_shape is not None:
x1 = np.clip(x1, 0, max_shape[1])
y1 = np.clip(y1, 0, max_shape[0])
x2 = np.clip(x2, 0, max_shape[1])
y2 = np.clip(y2, 0, max_shape[0])
return np.stack([x1, y1, x2, y2], axis=-1)