mazpie's picture
Initial commit
2d9a728
raw
history blame
2.92 kB
import numbers
import cv2
import numpy as np
import PIL
import torch
def _is_tensor_clip(clip):
return torch.is_tensor(clip) and clip.ndimension() == 4
def crop_clip(clip, min_h, min_w, h, w):
if isinstance(clip[0], np.ndarray):
cropped = [img[min_h:min_h + h, min_w:min_w + w, :] for img in clip]
elif isinstance(clip[0], PIL.Image.Image):
cropped = [
img.crop((min_w, min_h, min_w + w, min_h + h)) for img in clip
]
else:
raise TypeError('Expected numpy.ndarray or PIL.Image' +
'but got list of {0}'.format(type(clip[0])))
return cropped
def resize_clip(clip, size, interpolation='bilinear'):
if isinstance(clip[0], np.ndarray):
if isinstance(size, numbers.Number):
im_h, im_w, im_c = clip[0].shape
# Min spatial dim already matches minimal size
if (im_w <= im_h and im_w == size) or (im_h <= im_w
and im_h == size):
return clip
new_h, new_w = get_resize_sizes(im_h, im_w, size)
size = (new_w, new_h)
else:
size = size[0], size[1]
if interpolation == 'bilinear':
np_inter = cv2.INTER_LINEAR
else:
np_inter = cv2.INTER_NEAREST
scaled = [
cv2.resize(img, size, interpolation=np_inter) for img in clip
]
elif isinstance(clip[0], PIL.Image.Image):
if isinstance(size, numbers.Number):
im_w, im_h = clip[0].size
# Min spatial dim already matches minimal size
if (im_w <= im_h and im_w == size) or (im_h <= im_w
and im_h == size):
return clip
new_h, new_w = get_resize_sizes(im_h, im_w, size)
size = (new_w, new_h)
else:
size = size[1], size[0]
if interpolation == 'bilinear':
pil_inter = PIL.Image.BILINEAR
else:
pil_inter = PIL.Image.NEAREST
scaled = [img.resize(size, pil_inter) for img in clip]
else:
raise TypeError('Expected numpy.ndarray or PIL.Image' +
'but got list of {0}'.format(type(clip[0])))
return scaled
def get_resize_sizes(im_h, im_w, size):
if im_w < im_h:
ow = size
oh = int(size * im_h / im_w)
else:
oh = size
ow = int(size * im_w / im_h)
return oh, ow
def normalize(clip, mean, std, inplace=False):
if not _is_tensor_clip(clip):
raise TypeError('tensor is not a torch clip.')
if not inplace:
clip = clip.clone()
dtype = clip.dtype
mean = torch.as_tensor(mean, dtype=dtype, device=clip.device)
std = torch.as_tensor(std, dtype=dtype, device=clip.device)
clip.sub_(mean[:, None, None, None]).div_(std[:, None, None, None])
return clip