imread/imwrite and other issues

[Bill Denney]

Thomas L. Scofield wrote:
> Oops!  Concerning imread with png files, what I said about DOF was not 
> accurate.  A png image stored in matrix A
> with 4 channels has
>
>   size(A)(3) = 4
>
> so one needs to "lock out" the 4th channel for imshow with something like
>
>   imshow (A(:, :, 1:3))

This is just ignorance, but can imshow not produce an image with 
transparency?  If not, is there a reason not?  I'm imagining a case 
where I may want to change the background color of the axis before 
exporting a figure or similar.

Have a good day,

Bill