# Dynamic Convolutions: Exploiting Spatial Sparsity for Faster Inference Source: [Dynamic Convolutions: Exploiting Spatial Sparsity for Faster Inference]() Collection index: [llms.txt]() Data updated: 2025-10-26T00:28:36.143Z Authors: Thomas Verelst, Tinne Tuytelaars Published: 2019-12-06T16:11:16.000Z ## Abstract Modern convolutional neural networks apply the same operations on every pixel in an image. However, not all image regions are equally important. To address this inefficiency, we propose a method to dynamically apply convolutions conditioned on the input image. We introduce a residual block where a small gating branch learns which spatial positions should be evaluated. These discrete gating decisions are trained end-to-end using the Gumbel-Softmax trick, in combination with a sparsity criterion. Our experiments on CIFAR, ImageNet and MPII show that our method has better focus on the region of interest and better accuracy than existing methods, at a lower computational complexity. Moreover, we provide an efficient CUDA implementation of our dynamic convolutions using a gather-scatter approach, achieving a significant improvement in inference speed with MobileNetV2 residual blocks. On human pose estimation, a task that is inherently spatially sparse, the processing speed is increased by 60% with no loss in accuracy. ## Recorded benchmark results A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage. - [Object Detection on COCO 2017 (val)](): Object Detection; COCO 2017 (val); AP: not recorded. - [Instance Segmentation on COCO 2017 (val)](): Instance Segmentation; COCO 2017 (val); APm: not recorded. ## Original sources and implementation [Original paper]() [PDF]()