PaddleDetection/deploy/python/keypoint_preprocess.py

244 lines
8.0 KiB
Python

# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
this code is based on https://github.com/open-mmlab/mmpose/mmpose/core/post_processing/post_transforms.py
"""
import cv2
import numpy as np
class EvalAffine(object):
def __init__(self, size, stride=64):
super(EvalAffine, self).__init__()
self.size = size
self.stride = stride
def __call__(self, image, im_info):
s = self.size
h, w, _ = image.shape
trans, size_resized = get_affine_mat_kernel(h, w, s, inv=False)
image_resized = cv2.warpAffine(image, trans, size_resized)
return image_resized, im_info
def get_affine_mat_kernel(h, w, s, inv=False):
if w < h:
w_ = s
h_ = int(np.ceil((s / w * h) / 64.) * 64)
scale_w = w
scale_h = h_ / w_ * w
else:
h_ = s
w_ = int(np.ceil((s / h * w) / 64.) * 64)
scale_h = h
scale_w = w_ / h_ * h
center = np.array([np.round(w / 2.), np.round(h / 2.)])
size_resized = (w_, h_)
trans = get_affine_transform(
center, np.array([scale_w, scale_h]), 0, size_resized, inv=inv)
return trans, size_resized
def get_affine_transform(center,
input_size,
rot,
output_size,
shift=(0., 0.),
inv=False):
"""Get the affine transform matrix, given the center/scale/rot/output_size.
Args:
center (np.ndarray[2, ]): Center of the bounding box (x, y).
scale (np.ndarray[2, ]): Scale of the bounding box
wrt [width, height].
rot (float): Rotation angle (degree).
output_size (np.ndarray[2, ]): Size of the destination heatmaps.
shift (0-100%): Shift translation ratio wrt the width/height.
Default (0., 0.).
inv (bool): Option to inverse the affine transform direction.
(inv=False: src->dst or inv=True: dst->src)
Returns:
np.ndarray: The transform matrix.
"""
assert len(center) == 2
assert len(output_size) == 2
assert len(shift) == 2
if not isinstance(input_size, (np.ndarray, list)):
input_size = np.array([input_size, input_size], dtype=np.float32)
scale_tmp = input_size
shift = np.array(shift)
src_w = scale_tmp[0]
dst_w = output_size[0]
dst_h = output_size[1]
rot_rad = np.pi * rot / 180
src_dir = rotate_point([0., src_w * -0.5], rot_rad)
dst_dir = np.array([0., dst_w * -0.5])
src = np.zeros((3, 2), dtype=np.float32)
src[0, :] = center + scale_tmp * shift
src[1, :] = center + src_dir + scale_tmp * shift
src[2, :] = _get_3rd_point(src[0, :], src[1, :])
dst = np.zeros((3, 2), dtype=np.float32)
dst[0, :] = [dst_w * 0.5, dst_h * 0.5]
dst[1, :] = np.array([dst_w * 0.5, dst_h * 0.5]) + dst_dir
dst[2, :] = _get_3rd_point(dst[0, :], dst[1, :])
if inv:
trans = cv2.getAffineTransform(np.float32(dst), np.float32(src))
else:
trans = cv2.getAffineTransform(np.float32(src), np.float32(dst))
return trans
def get_warp_matrix(theta, size_input, size_dst, size_target):
"""This code is based on
https://github.com/open-mmlab/mmpose/blob/master/mmpose/core/post_processing/post_transforms.py
Calculate the transformation matrix under the constraint of unbiased.
Paper ref: Huang et al. The Devil is in the Details: Delving into Unbiased
Data Processing for Human Pose Estimation (CVPR 2020).
Args:
theta (float): Rotation angle in degrees.
size_input (np.ndarray): Size of input image [w, h].
size_dst (np.ndarray): Size of output image [w, h].
size_target (np.ndarray): Size of ROI in input plane [w, h].
Returns:
matrix (np.ndarray): A matrix for transformation.
"""
theta = np.deg2rad(theta)
matrix = np.zeros((2, 3), dtype=np.float32)
scale_x = size_dst[0] / size_target[0]
scale_y = size_dst[1] / size_target[1]
matrix[0, 0] = np.cos(theta) * scale_x
matrix[0, 1] = -np.sin(theta) * scale_x
matrix[0, 2] = scale_x * (
-0.5 * size_input[0] * np.cos(theta) + 0.5 * size_input[1] *
np.sin(theta) + 0.5 * size_target[0])
matrix[1, 0] = np.sin(theta) * scale_y
matrix[1, 1] = np.cos(theta) * scale_y
matrix[1, 2] = scale_y * (
-0.5 * size_input[0] * np.sin(theta) - 0.5 * size_input[1] *
np.cos(theta) + 0.5 * size_target[1])
return matrix
def rotate_point(pt, angle_rad):
"""Rotate a point by an angle.
Args:
pt (list[float]): 2 dimensional point to be rotated
angle_rad (float): rotation angle by radian
Returns:
list[float]: Rotated point.
"""
assert len(pt) == 2
sn, cs = np.sin(angle_rad), np.cos(angle_rad)
new_x = pt[0] * cs - pt[1] * sn
new_y = pt[0] * sn + pt[1] * cs
rotated_pt = [new_x, new_y]
return rotated_pt
def _get_3rd_point(a, b):
"""To calculate the affine matrix, three pairs of points are required. This
function is used to get the 3rd point, given 2D points a & b.
The 3rd point is defined by rotating vector `a - b` by 90 degrees
anticlockwise, using b as the rotation center.
Args:
a (np.ndarray): point(x,y)
b (np.ndarray): point(x,y)
Returns:
np.ndarray: The 3rd point.
"""
assert len(a) == 2
assert len(b) == 2
direction = a - b
third_pt = b + np.array([-direction[1], direction[0]], dtype=np.float32)
return third_pt
class TopDownEvalAffine(object):
"""apply affine transform to image and coords
Args:
trainsize (list): [w, h], the standard size used to train
use_udp (bool): whether to use Unbiased Data Processing.
records(dict): the dict contained the image and coords
Returns:
records (dict): contain the image and coords after tranformed
"""
def __init__(self, trainsize, use_udp=False):
self.trainsize = trainsize
self.use_udp = use_udp
def __call__(self, image, im_info):
rot = 0
imshape = im_info['im_shape'][::-1]
center = im_info['center'] if 'center' in im_info else imshape / 2.
scale = im_info['scale'] if 'scale' in im_info else imshape
if self.use_udp:
trans = get_warp_matrix(
rot, center * 2.0,
[self.trainsize[0] - 1.0, self.trainsize[1] - 1.0], scale)
image = cv2.warpAffine(
image,
trans, (int(self.trainsize[0]), int(self.trainsize[1])),
flags=cv2.INTER_LINEAR)
else:
trans = get_affine_transform(center, scale, rot, self.trainsize)
image = cv2.warpAffine(
image,
trans, (int(self.trainsize[0]), int(self.trainsize[1])),
flags=cv2.INTER_LINEAR)
return image, im_info
def expand_crop(images, rect, expand_ratio=0.3):
imgh, imgw, c = images.shape
label, conf, xmin, ymin, xmax, ymax = [int(x) for x in rect.tolist()]
if label != 0:
return None, None, None
org_rect = [xmin, ymin, xmax, ymax]
h_half = (ymax - ymin) * (1 + expand_ratio) / 2.
w_half = (xmax - xmin) * (1 + expand_ratio) / 2.
if h_half > w_half * 4 / 3:
w_half = h_half * 0.75
center = [(ymin + ymax) / 2., (xmin + xmax) / 2.]
ymin = max(0, int(center[0] - h_half))
ymax = min(imgh - 1, int(center[0] + h_half))
xmin = max(0, int(center[1] - w_half))
xmax = min(imgw - 1, int(center[1] + w_half))
return images[ymin:ymax, xmin:xmax, :], [xmin, ymin, xmax, ymax], org_rect