Aplha channel depending on intencity

[Kevich]

I have grayscale pic, and I need to set alpha channel of each pixel depending on white intecity. So if I have FF of intencity I'll need to have FF alpha channel, 22 -> 22 etc. Could someone help me how to do this using convert command line command
thanks in advance

[snibgo]

convert in.png -alpha on -channel alpha -fx r out.png

[fmw42]

try

convert grayimage.xxx -alpha copy transparentimage.png


see http://www.imagemagick.org/Usage/basics/#alpha_copy

[Kevich]

thank's a lot. Both methods are Okay =) i'm new at IM, so have some stucks, that's seems simple