Copypixel not replace Transparent pixels?

Hi,

I’m trying to use copypixel to copy an image and paste it onto an existing bitmap. However, the image I’m trying to copy has transparent pixels so when CopyPixel’s pastes the image onto my existing bitmap, the pixels already on the image is replaced by the transparent pixels from my image.

How can I make it so CopyPixel will only paste all pixels besides the transparent ones onto my bitmap?

Thanks.