If you run imfinfo('fyqslAx.png')
, you'll see that the 'Transparency'
is specified as 'simple'
and the 'SimpleTransparencyData'
is set to 0
(false
). I can't find documentation on this, but I think that this may indicate that the alpha channel has been compressed into the image data because the the image is binary and grayscale. Effectively the image is a binary mask, either transparent or not. You can display your image like this:
A = imread('fyqslAx.png');
h = imshow(A);
set(h, 'AlphaData', A);
If you try to return a colormap and/or alpha channel from imread
using extra output arguments, you'll see that both are empty.