Display transparent image on axes (MATLAB) -

so have transparent image (http://imgur.com/fyqslax) want display on axes in matlab transperancy. this, used code below, works other transparent png images have:

[a, map, alpha] = imread('fyqslax.png'); h = imshow(a, map) set(h, 'alphadata', alpha); 

this code however, not seem work image above. im guessing because has image being grayscale , having bitdepth of 1, resulting in map , alpha having nothing in (whereas other png transparent images have, have in map , alpha). if use this:

a = imread('fyqslax.png'); h = imshow(a) 

a black background appears image should transparent.

how display http://imgur.com/fyqslax transperancy on axes?

edit: horchler's method worked; thanks!!

if run imfinfo('fyqslax.png'), you'll see 'transparency' specified 'simple' , 'simpletransparencydata' set 0 (false). can't find documentation on this, think may indicate alpha channel has been compressed image data because the image binary , grayscale. image binary mask, either transparent or not. can display image this:

a = imread('fyqslax.png'); h = imshow(a); set(h, 'alphadata', a); 

if try return colormap and/or alpha channel imread using output arguments, you'll see both empty.