Embodiments relate to an image processing circuit able to perform image fusion on received images in a first mode for fusing demosaiced and downscaled image data, and a second mode for fusing raw image data. In the first mode, raw image data received from an image sensor is demosaiced and resampled prior to undergoing image fusion. On the other hand, in the second raw image mode, the image processing circuit performs image fusion on the raw image data, and demosaics and resamples the generated fused raw image. The image processing circuit comprises an image fusion circuit that processes images of received image pyramids differently, based on whether the first or second mode is being run. The image fusion circuit further comprises an additional alpha-blending circuit allowing for the image fusion circuit to perform a fusion and an alpha-blending in a single pass through image fusion circuit.