encouter messy augmented images when the image shape is not square

[silencelamb]

Hi, I encouter autoaugmented images below, and i locate the problem is caused by that the pic_array shape used in augmentations is in wrong oder and my image shape is not square.

fixmatch/third_party/auto_augment/augmentations.py

Lines 160 to 161 in 08d9b83

	s = pil_img.size
	pic_array = (np.array(pil_img.getdata()).reshape((s[0], s[1], 4)) / 255.0)

1. make it correct
   the size of PIL img is（width,height)
   the shape of np.array which can be converted to PIL img should by (height,width,c), so the right way is
   s = pil_img.size
pic_array = (np.array(pil_img.getdata()).reshape((s[1], s[0], 4)) / 255.0)

2. make it faster
   I find np.array(pil_img.getdata()).reshape() is really slow, the much faster way is np.array(pil_img)

3. By the way, i have a question: why 'RGBA' format is used? Is 'RGBA' format image necessary? I checked the valued of 'A’ channel of my images are all 255.
   Thank you.