Files
uniface/uniface/common.py
Yakhyokhuja Valikhujaev 0c93598007 feat: Enhace emotion inference speed on ARM and add FaceAnalyzer, Face classes for ease of use. (#25)
* feat: Update linting and type annotations, return types in detect

* feat: add face analyzer and face classes

* chore: Update the format and clean up some docstrings

* docs: Update usage documentation

* feat: Change AgeGender model output to 0, 1 instead of string (Female, Male)

* test: Update testing code

* feat: Add Apple silicon backend for torchscript inference

* feat: Add face analyzer example and add run emotion for testing
2025-11-30 20:32:07 +09:00

244 lines
8.3 KiB
Python

# Copyright 2025 Yakhyokhuja Valikhujaev
# Author: Yakhyokhuja Valikhujaev
# GitHub: https://github.com/yakhyo
import itertools
import math
from typing import List, Optional, Tuple
import cv2
import numpy as np
__all__ = [
'resize_image',
'generate_anchors',
'non_max_suppression',
'decode_boxes',
'decode_landmarks',
'distance2bbox',
'distance2kps',
]
def resize_image(frame, target_shape: Tuple[int, int] = (640, 640)) -> Tuple[np.ndarray, float]:
"""
Resize an image to fit within a target shape while keeping its aspect ratio.
Args:
frame (np.ndarray): Input image.
target_shape (Tuple[int, int]): Target size (width, height). Defaults to (640, 640).
Returns:
Tuple[np.ndarray, float]: Resized image on a blank canvas and the resize factor.
"""
width, height = target_shape
# Aspect-ratio preserving resize
im_ratio = float(frame.shape[0]) / frame.shape[1]
model_ratio = height / width
if im_ratio > model_ratio:
new_height = height
new_width = int(new_height / im_ratio)
else:
new_width = width
new_height = int(new_width * im_ratio)
resize_factor = float(new_height) / frame.shape[0]
resized_frame = cv2.resize(frame, (new_width, new_height))
# Create blank image and place resized image on it
image = np.zeros((height, width, 3), dtype=np.uint8)
image[:new_height, :new_width, :] = resized_frame
return image, resize_factor
def generate_anchors(image_size: Tuple[int, int] = (640, 640)) -> np.ndarray:
"""
Generate anchor boxes for a given image size (RetinaFace specific).
Args:
image_size (Tuple[int, int]): Input image size (width, height). Defaults to (640, 640).
Returns:
np.ndarray: Anchor box coordinates as a NumPy array with shape (num_anchors, 4).
"""
steps = [8, 16, 32]
min_sizes = [[16, 32], [64, 128], [256, 512]]
anchors = []
feature_maps = [[math.ceil(image_size[0] / step), math.ceil(image_size[1] / step)] for step in steps]
for k, (map_height, map_width) in enumerate(feature_maps):
step = steps[k]
for i, j in itertools.product(range(map_height), range(map_width)):
for min_size in min_sizes[k]:
s_kx = min_size / image_size[1]
s_ky = min_size / image_size[0]
dense_cx = [x * step / image_size[1] for x in [j + 0.5]]
dense_cy = [y * step / image_size[0] for y in [i + 0.5]]
for cy, cx in itertools.product(dense_cy, dense_cx):
anchors += [cx, cy, s_kx, s_ky]
output = np.array(anchors, dtype=np.float32).reshape(-1, 4)
return output
def non_max_suppression(dets: np.ndarray, threshold: float) -> List[int]:
"""
Apply Non-Maximum Suppression (NMS) to reduce overlapping bounding boxes based on a threshold.
Args:
dets (np.ndarray): Array of detections with each row as [x1, y1, x2, y2, score].
threshold (float): IoU threshold for suppression.
Returns:
List[int]: Indices of bounding boxes retained after suppression.
"""
x1 = dets[:, 0]
y1 = dets[:, 1]
x2 = dets[:, 2]
y2 = dets[:, 3]
scores = dets[:, 4]
areas = (x2 - x1 + 1) * (y2 - y1 + 1)
order = scores.argsort()[::-1]
keep = []
while order.size > 0:
i = order[0]
keep.append(i)
xx1 = np.maximum(x1[i], x1[order[1:]])
yy1 = np.maximum(y1[i], y1[order[1:]])
xx2 = np.minimum(x2[i], x2[order[1:]])
yy2 = np.minimum(y2[i], y2[order[1:]])
w = np.maximum(0.0, xx2 - xx1 + 1)
h = np.maximum(0.0, yy2 - yy1 + 1)
inter = w * h
ovr = inter / (areas[i] + areas[order[1:]] - inter)
inds = np.where(ovr <= threshold)[0]
order = order[inds + 1]
return keep
def decode_boxes(loc: np.ndarray, priors: np.ndarray, variances: Optional[List[float]] = None) -> np.ndarray:
"""
Decode locations from predictions using priors to undo
the encoding done for offset regression at train time (RetinaFace specific).
Args:
loc (np.ndarray): Location predictions for loc layers, shape: [num_priors, 4]
priors (np.ndarray): Prior boxes in center-offset form, shape: [num_priors, 4]
variances (Optional[List[float]]): Variances of prior boxes. Defaults to [0.1, 0.2].
Returns:
np.ndarray: Decoded bounding box predictions with shape [num_priors, 4]
"""
if variances is None:
variances = [0.1, 0.2]
# Compute centers of predicted boxes
cxcy = priors[:, :2] + loc[:, :2] * variances[0] * priors[:, 2:]
# Compute widths and heights of predicted boxes
wh = priors[:, 2:] * np.exp(loc[:, 2:] * variances[1])
# Convert center, size to corner coordinates
boxes = np.zeros_like(loc)
boxes[:, :2] = cxcy - wh / 2 # xmin, ymin
boxes[:, 2:] = cxcy + wh / 2 # xmax, ymax
return boxes
def decode_landmarks(
predictions: np.ndarray, priors: np.ndarray, variances: Optional[List[float]] = None
) -> np.ndarray:
"""
Decode landmark predictions using prior boxes (RetinaFace specific).
Args:
predictions (np.ndarray): Landmark predictions, shape: [num_priors, 10]
priors (np.ndarray): Prior boxes, shape: [num_priors, 4]
variances (Optional[List[float]]): Scaling factors for landmark offsets. Defaults to [0.1, 0.2].
Returns:
np.ndarray: Decoded landmarks, shape: [num_priors, 10]
"""
if variances is None:
variances = [0.1, 0.2]
# Reshape predictions to [num_priors, 5, 2] to process landmark points
predictions = predictions.reshape(predictions.shape[0], 5, 2)
# Expand priors to match (num_priors, 5, 2)
priors_xy = np.repeat(priors[:, :2][:, np.newaxis, :], 5, axis=1) # (num_priors, 5, 2)
priors_wh = np.repeat(priors[:, 2:][:, np.newaxis, :], 5, axis=1) # (num_priors, 5, 2)
# Compute absolute landmark positions
landmarks = priors_xy + predictions * variances[0] * priors_wh
# Flatten back to [num_priors, 10]
landmarks = landmarks.reshape(landmarks.shape[0], -1)
return landmarks
def distance2bbox(points: np.ndarray, distance: np.ndarray, max_shape: Optional[Tuple[int, int]] = None) -> np.ndarray:
"""
Decode distance prediction to bounding box (SCRFD specific).
Args:
points (np.ndarray): Anchor points with shape (n, 2), [x, y].
distance (np.ndarray): Distance from the given point to 4
boundaries (left, top, right, bottom) with shape (n, 4).
max_shape (Optional[Tuple[int, int]]): Shape of the image (height, width) for clipping.
Returns:
np.ndarray: Decoded bounding boxes with shape (n, 4) as [x1, y1, x2, y2].
"""
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])
else:
x1 = np.maximum(x1, 0)
y1 = np.maximum(y1, 0)
x2 = np.maximum(x2, 0)
y2 = np.maximum(y2, 0)
return np.stack([x1, y1, x2, y2], axis=-1)
def distance2kps(points: np.ndarray, distance: np.ndarray, max_shape: Optional[Tuple[int, int]] = None) -> np.ndarray:
"""
Decode distance prediction to keypoints (SCRFD specific).
Args:
points (np.ndarray): Anchor points with shape (n, 2), [x, y].
distance (np.ndarray): Distance from the given point to keypoints with shape (n, 2k).
max_shape (Optional[Tuple[int, int]]): Shape of the image (height, width) for clipping.
Returns:
np.ndarray: Decoded keypoints with shape (n, 2k).
"""
preds = []
for i in range(0, distance.shape[1], 2):
px = points[:, i % 2] + distance[:, i]
py = points[:, i % 2 + 1] + distance[:, i + 1]
if max_shape is not None:
px = np.clip(px, 0, max_shape[1])
py = np.clip(py, 0, max_shape[0])
preds.append(px)
preds.append(py)
return np.stack(preds, axis=-1)