An image augmentation library for tensorflow. The libray is designed to be easily used with tf.data.Dataset. The augmentor accepts tf.data.Dataset object or a nested tuple of numpy array.
Original | Flip | Rotation | Translation |
---|---|---|---|
Crop | Elactic Deform | ||
Gaussian Blur | Contrast | Gamma | |
Random Rotation | Random Translation | Random Crop |
---|---|---|
Random Contrast | Random Gamma | Elastic Deform |
tfAugmentor is written in Python and can be easily installed via:
pip install tfAugmentor
Required packages:
tfAugmentor is implemented to work seamlessly with tf.data. The tf.data.Dataset object can be directly processed by tfAugmentor.
To instantiate an Augmentor
object, three arguments are required:
class Augmentor(object):
def __init__(self, signature, image=[], label_map=[]):
...
Note: only the items in 'image' and 'label' will be processed, others will remain untouched
import tfAugmentor as tfaug
# new tfAugmentor object
aug = tfaug.Augmentor(signature=('image', ('mask1', 'mask2')),
image=['image'],
label=['mask1', 'mask2'])
# add augumentation operations
aug.flip_left_right(probability=0.5)
aug.rotate90(probability=0.5)
aug.elastic_deform(strength=2, scale=20, probability=1)
# assume we have three numpy arrays
X_image = ... # shape [batch, height, width, channel]
Y_mask1 = ... # shape [batch, height, width, 1]
Y_mask2 = ... # shape [batch, height, width, 1]
# create tf.data.Dataset object
tf_dataset = tf.data.Dataset.from_tensor_slices((X_image, (Y_mask1, Y_mask2))))
# do the actual augmentation
ds1 = aug(tf_dataset)
# or you can directly pass the numpy arrays, a tf.data.Dataset object will be returned
ds2 = aug((X_image, (Y_mask1, Y_mask2))), keep_size=True)
If the data is passed as a python dictionary, the signature should be the list/tuple of keys. For example:
import tfAugmentor as tfaug
# new tfAugmentor object
aug = tfaug.Augmentor(signature=('image', 'mask1', 'mask2'),
image=['image'],
label=['mask1', 'mask2'])
# add augumentation operations
aug.flip_left_right(probability=0.5)
aug.rotate90(probability=0.5)
aug.elastic_deform(strength=2, scale=20, probability=1)
# assume we have three numpy arrays
X_image = ... # shape [batch, height, width, channel]
Y_mask1 = ... # shape [batch, height, width, 1]
Y_mask2 = ... # shape [batch, height, width, 1]
ds_dict = {'image': X_image,
'mask1': Y_mask1,
'mask2': Y_mask2}
# create tf.data.Dataset object
tf_dataset = tf.data.Dataset.from_tensor_slices(ds_dict)
# do the actual augmentation
ds1 = aug(tf_dataset)
# or directly pass the data
ds2 = aug(ds_dict)
Note: All added operations will be executed one by one, but you can create multiply tfAugmentor to realize parallel pipelines
import tfAugmentor as tfaug
# since 'class' is neither in 'image' nor in 'label', it will not be processed
aug1 = tfaug.Augmentor((('image_rgb', 'image_depth'), ('semantic_mask', 'class')),
image=['image_rgb', 'image_depth'],
label=['semantic_mask'])
aug2 = tfaug.Augmentor((('image_rgb', 'image_depth'), ('semantic_mask', 'class')),
image=['image_rgb', 'image_depth'],
label=['semantic_mask'])
# add different augumentation operations to aug1 and aug2
aug1.flip_left_right(probability=0.5)
aug1.random_crop_resize(sacle_range=(0.7, 0.9), probability=0.5)
aug2.elastic_deform(strength=2, scale=20, probability=1)
# assume we have the 1000 data samples
X_rgb = ... # shape [1000 x 512 x 512 x 3]
X_depth = ... # shape [1000 x 512 x 512 x 1]
Y_semantic_mask = ... # shape [1000 x 512 x 512 x 1]
Y_class = ... # shape [1000 x 1]
# create tf.data.Dataset object
ds_origin = tf.data.Dataset.from_tensor_slices(((X_rgb, X_depth), (Y_semantic_mask, Y_class))))
# do the actual augmentation
ds1 = aug1(ds_origin)
ds2 = aug2(ds_origin)
# combine them
ds = ds_origin.concatenate(ds1)
ds = ds.concatenate(ds1)
The argument 'probability' controls the possibility of a certain augmentation taking place.
# flip the image left right
aug.flip_left_right(probability=1)
# flip the image up down
aug.flip_up_down(probability=1)
# rotate by 90 degree clockwise
a.rotate90(probability=1)
# rotate by 180 degree clockwise
a.rotate180(probability=1)
# rotate by 270 degree clockwise
a.rotate270(probability=1)
# rotate by a certrain degree, Args: angle - scala, in degree
a.rotate(angle, probability=1)
# randomly rotate the image
a.random_rotate(probability=1)
# tranlate image, Args: offset - [x, y]
a.translate(offset, probability=1):
# randoms translate image
a.random_translate(translation_range=[-100, 100], probability=1):
# randomly crop a sub-image and resize to the original image size
a.random_crop(scale_range=([0.5, 0.8], preserve_aspect_ratio=False, probability=1)
# performa elastic deformation
a.elastic_deform(scale=10, strength=200, probability=1)
# adjust image contrast randomly
a.random_contrast(contrast_range=[0.6, 1.4], probability=1)
# perform gamma correction with random gamma values
a.random_gamma(gamma_range=[0.5, 1.5], probability=1)
# blur the image with gaussian kernel
a.gaussian_blur(sigma=2, probability=1)