Due to the visual properties of reflection and refraction, RGB-D cameras cannot accurately capture the depth of transparent objects, leading to incomplete depth maps. To fill in the missing points, recent studies tend to explore new visual features and design complex networks to reconstruct the depth, however, these approaches tremendously increase computation, and the correlation of different visual features remains a problem. To this end, we propose an efficient depth completion network named DistillGrasp which distillates knowledge from the teacher branch to the student branch. Specifically, in the teacher branch, we design a position correlation block (PCB) that leverages RGB images as the query and key to search for the corresponding values, guiding the model to establish correct correspondence between two features and transfer it to the transparent areas. For the student branch, we propose a consistent feature correlation module (CFCM) that retains the reliable regions of RGB images and depth maps respectively according to the consistency and adopts a CNN to capture the pairwise relationship for depth completion. To avoid the student branch only learning regional features from the teacher branch, we devise a distillation loss that not only considers the distance loss but also the object structure and edge information. Extensive experiments conducted on the ClearGrasp dataset manifest that our teacher network outperforms state-of-the-art methods in terms of accuracy and generalization, and the student network achieves competitive results with a higher speed of 48 FPS. In addition, the significant improvement in a real-world robotic grasping system illustrates the effectiveness and robustness of our proposed system.

Deep neural networks have achieved remarkable advancement in various intelligence tasks. However, the massive computation and storage consumption limit applications on resource-constrained devices. While channel pruning has been widely applied to compress models, it is challenging to reach very deep compressions for such a coarse-grained pruning structure without significant performance degradation. In this article, we propose an acceleration-aware fine-grained channel pruning (AFCP) framework for accelerating neural networks, which optimizes trainable gate parameters by estimating residual errors between pruned and original channels with hardware characteristics. Our fine-grained concept consists of both algorithm and structure levels. Different from existing methods that leverage a predefined pruning criterion, AFCP explicitly considers both zero-out and similar criteria for each channel, and adaptively selects the suitable one via residual gate parameters. For structure level, AFCP adopts a fine-grained channel pruning strategy for residual neural networks and a decomposition-based structure, which further extends the pruning optimization space. Moreover, instead of using theoretical computation costs, such as floating-point operations, we propose the hardware predictor that bridges the gap between realistic acceleration and pruning procedure to guide the learning of pruning, which improves the efficiency of model pruning when deployed on accelerators. Extensive evaluation results demonstrate that AFCP outperforms state-of-the-art methods, and achieves a favorable balance between model performance and computation cost.

Deep Neural Networks (DNNs) have achieved remarkable success in various Artificial Intelligence applications. Quantization is a critical step in DNNs compression and acceleration for deployment. To further boost DNN execution efficiency, many works explore to leverage the input-dependent redundancy with dynamic quantization for different regions. However, the sensitive regions in the feature map are irregularly distributed, which restricts the real speed up for existing accelerators. To this end, we propose an algorithm-architecture co-design, named Structured Dynamic Precision (SDP). Specifically, we propose a quantization scheme in which the high-order bit part and the low-order bit part of data can be masked independently. And a fixed number of term parts are dynamically selected for computation based on the importance of each term in the group. We also present a hardware design to enable the algorithm efficiently with small overheads, whose inference time mainly scales with the precision proportionally. Evaluation experiments on extensive networks demonstrate that compared to the state-of-the-art dynamic quantization accelerator DRQ, our SDP can achieve 29% performance gain and 51% energy reduction for the same level of model accuracy.

The state-of-the-art convolutional neural network accelerators are showing a growing interest in exploiting the bit-level sparsity and eliminating the ineffectual computations of zero bits. However, the excessive redundancy and the irregular distribution of nonzero bits limit the real speedup in the accelerators. To address this, we propose an algorithm-architecture codesign, named structured term pruning (STP), to boost the computation efficiency of neural networks inference. Specifically, we enhance the bit sparsity by guiding the weights toward the value with fewer power-of-two terms. Then, we structure the terms with layer-wise group budgets. Retraining is adopted to recover the accuracy drop. We also design the hardware of the group processing element and the fast signed-digital encoder for efficient implementation of STP networks. The system design of STP is realized with some easy alterations on an input stationary systolic array design. Extensive evaluation results demonstrate that STP can reduce significant inference computation costs, and achieve $2.35\times $ computational energy saving for the ResNet18 network on the ImageNet dataset.

The rise in ageing population is a global trend and this increasing number of elderly requires the development of new techniques, especially in the healthcare. Nowadays, already a lot of research is conducted with respect to the development of healthcare robots. However, these robots often focus on practical tasks and lack on a social interaction level. To enhance these social skills it is necessary to analyze both verbal and non-verbal communication. This paper focuses on the latter form of communication, more specific on emotion detection. To accomplish this the developed algorithm extracts specific facial cues, in the form of displacement ratios, and interprets these cues with a cascade of SVMs. In total there are 4 different steps to achieve the emotion detection. First, the countenance is detected with an adapted Histogram of Oriented Gradients (HoG) algorithm. Subsequently, 19 feature points are derived from the facial region. The next step comprises the calculation of 12 displacement ratios based on the distance between those feature points in successive frames. Finally, the displacement ratios are used as feature vectors for a multi-class SVM in cascade with a binary SVM. The developed algorithm is evaluated on the Extended Cohn-Kanade (CK+) dataset and has an overall accuracy of 89.78% with a detection speed of less than 30ms, which makes it suitable for real-time applications.