Learning to do multiframe blind deconvolution unsupervisedly
share
Observation from ground based telescopes are affected by the presence of the Earth atmosphere, which severely perturbs them. The use of adaptive optics techniques has allowed us to partly beat this limitation. However, image selection or post-facto image reconstruction methods are routinely needed to reach the diffraction limit of telescopes. Deep learning has been recently used to accelerate these image reconstructions. Currently, these deep neural networks are trained with supervision, so that standard deconvolution algorithms need to be applied a-priori to generate the training sets. Our aim is to propose an unsupervised method which can then be trained simply with observations and check it with data from the FastCam instrument. We use a neural model composed of three neural networks that are trained end-to-end by leveraging the linear image formation theory to construct a physically-motivated loss function. The analysis of the trained neural model shows that multiframe blind deconvolution can be trained self-supervisedly, i.e., using only observations. The output of the network are the corrected images and also estimations of the instantaneous wavefronts. The network model is of the order of 1000 times faster than applying standard deconvolution based on optimization. With some work, the model can bed used on real-time at the telescope.
READ FULL TEXT