fast-reid/utils/transforms.py

81 lines
2.3 KiB
Python

# encoding: utf-8
"""
@author: liaoxingyu
@contact: sherlockliao01@gmail.com
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
import random
from PIL import Image
from torchvision import transforms as T
class Random2DTranslation(object):
"""
With a probability, first increase image size to (1 + 1/8), and then perform random crop.
Args:
height (int): target height.
width (int): target width.
p (float): probability of performing this transformation. Default: 0.5.
"""
def __init__(self, height, width, p=0.5, interpolation=Image.BILINEAR):
self.height = height
self.width = width
self.p = p
self.interpolation = interpolation
def __call__(self, img):
"""
Args:
img (PIL Image): Image to be cropped.
Returns:
PIL Image: Cropped image.
"""
if random.random() < self.p:
return img.resize((self.width, self.height), self.interpolation)
new_width, new_height = int(
round(self.width * 1.125)), int(round(self.height * 1.125))
resized_img = img.resize((new_width, new_height), self.interpolation)
x_maxrange = new_width - self.width
y_maxrange = new_height - self.height
x1 = int(round(random.uniform(0, x_maxrange)))
y1 = int(round(random.uniform(0, y_maxrange)))
croped_img = resized_img.crop(
(x1, y1, x1 + self.width, y1 + self.height))
return croped_img
class TrainTransform(object):
def __init__(self, h, w):
self.h = h
self.w = w
def __call__(self, x):
x = Random2DTranslation(self.h, self.w)(x)
x = T.RandomHorizontalFlip()(x)
x = T.ToTensor()(x)
x = T.Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])(x)
return x
class TestTransform(object):
def __init__(self, h, w):
self.h = h
self.w = w
def __call__(self, x=None):
x = T.Resize((self.h, self.w))(x)
x = T.ToTensor()(x)
x = T.Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])(x)
return x