background transparency problem

[pksingh_alld]

I'm using following command with transparent png image "heart.png" has black background when applied opacity in -draw command.

convert -size 500x500 xc:white -draw "translate 225,250 opacity 0.5 image over -200,-150 450,300 'heart.png'" output.jpg


Can anyone help me in this please?

[snibgo]

JPG doesn't support transparency.

[pksingh_alld]

its not a matter what is output format... i wants to apply opacity on heart.png and outcome of that write on output file(jpg or png). my problem is I don't wants opacity on transparent area. by default its assumes black background and applied opacity on whole area in place of graphics only. I can get it using following command

convert heart.png -matte -channel A -evaluate set 50% -channel rgba output.png

or

convert heart.png -matte -channel A +level 0,50% +channel output.png

but i wants it using -draw command.