Deep Back-Projection Networks For Super-Resolution

Muhammad Haris, Greg Shakhnarovich, Norimichi Ukita

Winner (1st) of NTIRE2018 Competition (Track: x8 Bicubic Downsampling)

Winner of PIRM2018 (1st on Region 2, 3rd on Region 1, and 5th on Region 3)

Honorable Mention Award in NTIRE2019 challenge on image enhancement

Runner-up Award in AIM2019 challenge on exetreme super-resolution

Abstract

The feed-forward architectures of recently proposed deep super-resolution networks learn representations of low-resolution inputs, and the non-linear mapping from those to high-resolution output. However, this approach does not fully address the mutual dependencies of low- and high-resolution images. We propose Deep Back-Projection Networks (DBPN), that exploit iterative up- and down-sampling layers, providing an error feedback mechanism for projection errors at each stage. We construct mutually-connected up- and down-sampling stages each of which represents different types of image degradation and high-resolution components. We show that extending this idea to allow concatenation of features across up- and down-sampling stages (Dense DBPN) allows us to reconstruct further improve super-resolution, yielding superior results and in particular establishing new state of the art results for large scaling factors such as 8x across multiple data sets.

Manuscript

Code

Results on 8x

Citation

Muhammad Haris, Greg Shakhnarovich, and Norimichi Ukita, "Deep Back-Projection Networks For Super-Resolution", Proc. of IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2018.

Muhammad Haris, Greg Shakhnarovich, and Norimichi Ukita, "Deep Back-Projection Networks For Single Image Super-Resolution", arXiv preprint arXiv:1904.05677, 2019.