PaddleClas/ppcls/data/preprocess/ops/hide_and_seek.py

46 lines
1.5 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/kkanshul/Hide-and-Seek
# reference: http://krsingh.cs.ucdavis.edu/krishna_files/papers/hide_and_seek/my_files/iccv2017.pdf
import numpy as np
import random
class HideAndSeek(object):
def __init__(self):
# possible grid size, 0 means no hiding
self.grid_sizes = [0, 16, 32, 44, 56]
# hiding probability
self.hide_prob = 0.5
def __call__(self, img):
# randomly choose one grid size
grid_size = np.random.choice(self.grid_sizes)
_, h, w = img.shape
# hide the patches
if grid_size == 0:
return img
for x in range(0, w, grid_size):
for y in range(0, h, grid_size):
x_end = min(w, x + grid_size)
y_end = min(h, y + grid_size)
if (random.random() <= self.hide_prob):
img[:, x:x_end, y:y_end] = 0
return img