ImageCompose

ImageCompose[image,overlay] gives the result of overlaying overlay onto image. 

ImageCompose[image,{overlay,α}] gives the result of alpha blending overlay into image using blending fraction α.

ImageCompose[image,overlay,pos] places the center of overlay at position pos in image.

ImageCompose[image,overlay,pos,opos] places the point opos in overlay at position pos in image.

ImageCompose[image,overlay,pos,opos,{fi,fo,mode}] uses the compositing fractions fk and the specified compositing mode.

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