Laplacian pyramid blending is a simple yet effective tool for many applications, including object composition, seamless panorama stitching, and exposure fusion. 

In this video, we discuss how to construct a Laplacian pyramid and how to use it to blend images. We then look at the implementation with a code example. 

00:00 Applications of image blending
00:35 Feather blending
01:36 Laplacian pyramid
02:54 Reconstruction with Laplacian pyramid
03:29 Laplacian pyramid blending
04:29 Exposure fusion
05:58 Code example

Video made with Manim: https://www.manim.community/

Jia-Bin Huang

Laplacian pyramid blending is a 40-year-old technique for seamlessly combining images by decomposing them into frequency components. Low-frequency regions blend gradually to avoid harsh transitions, while high-frequency details blend quickly to prevent ghosting. The method involves building Gaussian pyramids (repeated blur and downsample), computing Laplacian pyramids (residuals between levels), blending at each frequency level using weight masks, then reconstructing the final image. Applications include object compositing, panorama stitching, and exposure fusion for HDR-like results without full HDR conversion. A Python implementation walkthrough is provided.

How a 40-Year-Old Trick Solves Seamless Image Blending