[OPTICAL REVIEW Vol. 17, No. 3 (2010) 114-122]
© 2010 The Japan Society of Applied Physics

Texton-Based Super-Resolution for Achieving High Spatiotemporal Resolution in Hybrid Camera System

Kenji KAMIMURA*, Norimichi TSUMURA1, Toshiya NAKAGUCHI1, and Yoichi MIYAKE2

Graduate School of Science and Technology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
1Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
2Research Center for Frontier Medical Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan

(Received September 1, 2009; Accepted March 6, 2010)

Many super-resolution methods have been proposed to enhance the spatial resolution of images by using iteration and multiple input images. In a previous paper, we proposed the example-based super-resolution method to enhance an image through pixel-based texton substitution to reduce the computational cost. In this method, however, we only considered the enhancement of a texture image. In this study, we modified this texton substitution method for a hybrid camera to reduce the required bandwidth of a high-resolution video camera. We applied our algorithm to pairs of high- and low-spatiotemporal-resolution videos, which were synthesized to simulate a hybrid camera. The result showed that the fine detail of the low-resolution video can be reproduced compared with bicubic interpolation and the required bandwidth could be reduced to about 1/5 in a video camera. It was also shown that the peak signal-to-noise ratios (PSNRs) of the images improved by about 6 dB in a trained frame and by 1.0–1.5 dB in a test frame, as determined by comparison with the processed image using bicubic interpolation, and the average PSNRs were higher than those obtained by the well-known Freeman's patch-based super-resolution method. Compared with that of the Freeman's patch-based super-resolution method, the computational time of our method was reduced to almost 1/10.

Key words: super-resolution, texton, video, wavelet transform

*E-mail address: kamimura@auone.jp