Change White to Transparent

[Don Wells]

I have a png file in grayscale. I would like to change all of the whitish areas to transparent, allowing me to overlay it on another image. Any ideas?

T.I.A.

[HansV]

Do you have PhotoShop? If so, see for example How to Make a Transparent PNG With Photoshop | eHow.com and/or Photoshop Tip 3: Transparent PNGs.

I think IrfanView will let you choose a color to become transparent when saving a .png, but I don't have IrfanView on my PC anymore.

[Don Wells]

I think IrfanView will let you choose a color to become transparent when saving a .png, but I don't have IrfanView on my PC anymore.

As usual, your thinking is absolutely correct. Many Thanks Hans.