Deep and Wide Multiscale Recursive Networks for Robust Image Labeling
This work addresses the need for more accurate image labeling systems, especially in the domain-specific area of neural circuitry reconstruction, though it appears incremental as it builds upon existing network architectures.
The authors tackled the problem of improving image labeling accuracy, particularly for boundary prediction in connectomic reconstruction from 3D electron microscopy data, by proposing Deep And Wide Multiscale Recursive (DAWMR) networks, which achieved new levels of performance with features like a large field of view of 157,464 voxels and faster training times.
Feedforward multilayer networks trained by supervised learning have recently demonstrated state of the art performance on image labeling problems such as boundary prediction and scene parsing. As even very low error rates can limit practical usage of such systems, methods that perform closer to human accuracy remain desirable. In this work, we propose a new type of network with the following properties that address what we hypothesize to be limiting aspects of existing methods: (1) a `wide' structure with thousands of features, (2) a large field of view, (3) recursive iterations that exploit statistical dependencies in label space, and (4) a parallelizable architecture that can be trained in a fraction of the time compared to benchmark multilayer convolutional networks. For the specific image labeling problem of boundary prediction, we also introduce a novel example weighting algorithm that improves segmentation accuracy. Experiments in the challenging domain of connectomic reconstruction of neural circuity from 3d electron microscopy data show that these "Deep And Wide Multiscale Recursive" (DAWMR) networks lead to new levels of image labeling performance. The highest performing architecture has twelve layers, interwoven supervised and unsupervised stages, and uses an input field of view of 157,464 voxels ($54^3$) to make a prediction at each image location. We present an associated open source software package that enables the simple and flexible creation of DAWMR networks.