what is the pupose of these two lines in create_input_files function in "master/utils.py"?

[naveen-marthala]

I was going through the code and couldn't comprehend what was going on in these two lines of code:

what does the if check and what does the lines inside if do?

a-PyTorch-Tutorial-to-Image-Captioning/utils.py

Lines 116 to 118 in cc9c7e2

	if len(img.shape) == 2:
	img = img[:, :, np.newaxis]
	img = np.concatenate([img, img, img], axis=2)

and what is being "assert"ed in this line?

a-PyTorch-Tutorial-to-Image-Captioning/utils.py

Line 139 in cc9c7e2

assert images.shape[0] * captions_per_image == len(enc_captions) == len(caplens)

Any help is appreciated. Thanks.

[secretsather]

It's checking to make sure the images are not single channel (i.e. grayscale) and if so, creates an RGB images using the gray channel repeated (3) times.