Fig. 3.

Hyperspectral endoscopic line-scan slices can be co-registered using wide-field reference images. a The three main types of image deformation were first emulated in simulation. Three types of image deformation were applied during an endoscopic procedure, in which the image x axis was scanned. b Seventy-four wide-field images were successfully co-registered and a combined image produced. c The geometric transformation matrix obtained from the wide-field image registration procedure was then applied to the simulated spectral image data. Images are shown from four different simulated wavelengths. d Combined image from 360 experimentally measured and co-registered wide-field images of a USAF 1951 resolution target. e Images from the experimentally reconstructed hypercube at two different wavelengths: 495.7 and 610.4 nm. Images acquired using the external illumination method. Scale bar in simulation a–c = 100 pixels. Scale bar in experimental data d, e = 1 mm. Dashed squares in b and d indicate the slit scanning areas where spectral images were obtained