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Exploiting multi‐scale features is one of the most effective methods to recognize objects of different scales in object detection. Since image pyramid is time‐consuming, Feature Pyramid Network (FPN) becomes the most popular component used for obtaining pyramidal features. Despite its effectiveness, there still exist some intrinsic defects. In this work, it is attributed to insufficient information flow and a Deformable Cross‐scale Interaction Feature Pyramid Network (DCIFPN) is proposed, which aims to promote the information transfer process with content‐aware sampling and dynamic aggregation weights. More specifically, Deformable Semantic Enhancement Module (DSEM) is designed that can construct accurate information flow with dynamic aggregation weights. In addition, Deformable Spatial Refinement Module (DSRM) is proposed to enhance high‐level features with low‐level location details. When DCIFPN is deployed on RetinaNet and FCOS with ResNet‐50, the performance is improved by 1.6 AP and 1.1 AP, respectively, on the challenging MS COCO benchmark. Apart from one‐stage detectors, DCIFPN is also applicable to two‐stage methods such as Faster R‐CNN and Mask R‐CNN. Further experiments on Pascal VOC and CrowdHuman datasets can verify the effectiveness and generalization of the method. [ABSTRACT FROM AUTHOR]

We present a novel and efficient approach to estimate 6D object poses of known objects in complex scenes represented by point clouds. Our approach is based on the well-known point pair feature (PPF) matching, which utilizes self-similar point pairs to compute potential matches and thereby cast votes for the object pose by a voting scheme. The main contribution of this paper is to present an improved PPF-based recognition framework, especially a new center voting strategy based on the relative geometric relationship between the object center and point pair features. Using this geometric relationship, we first generate votes to object centers resulting in vote clusters near real object centers. Then we group and aggregate these votes to generate a set of pose hypotheses. Finally, a pose verification operator is performed to filter out false positives and predict appropriate 6D poses of the target object. Our approach is also suitable to solve the multi-instance and multi-object detection tasks. Extensive experiments on a variety of challenging benchmark datasets demonstrate that the proposed algorithm is discriminative and robust towards similar-looking distractors, sensor noise, and geometrically simple shapes. The advantage of our work is further verified by comparing to the state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

This paper describes a novel hardware-oriented algorithm that can be implemented on a field-programmable gate array in a high-speed vision platform for detection of multiple objects with clear texture information in images of $512\times 512$ pixels at 10 000 frames per second (fps) under complex background. The proposed algorithm is specially designed for devices with limited hardware resource for high-frame-rate, high-data-throughput, and high-parallelism processing of video streams with low latency. The proposed algorithm is based on the conventional histograms of oriented gradient (HOG) descriptor and support vector machine classifier algorithms. Considering the trade-off between speed and accuracy, many hardware-based optimization operations were implemented. The data throughput is nearly 29.30 Gbps while the latency for feature extraction is 0.76 us (61 clock period). After hardware-based image processing, the source image and the detected object features can be transferred to a personal computer for recording or post-processing at 10 000 fps. Several experiments were done to demonstrate the performance of our proposed algorithm for ultra-high-speed moving object detection with clear texture information in images. [ABSTRACT FROM AUTHOR]

We present a high-speed vision-based morphological analysis system for fast-flowing cells in a microchannel. Real-time video processing is performed in hardware logic by extracting the moment features and bounding boxes of multiple cells in 512 \times 256-pixel images at 2000 fps. The extracted cell regions are pushed into a first-in–first-out (FIFO) buffer for real-time image-based morphological analysis after being shrunk proportionally to a certain size. By extracting the bounding boxes of the cell regions using hardware logic and shrinking the cell region to a certain size to reduce processing time, our high-speed vision system can perform fast morphological analysis of cells at 500 cells/s in fast microchannel flows. Moreover, snapshots of all passed cells under the microscope are stored for offline verification. The results of real-time experiments conducted to analyze the size, eccentricity, and transparency of sea urchin embryos flowing fast in microchannels verify the efficacy of our vision-based cell analysis system. [ABSTRACT FROM AUTHOR]

This paper proposes a novel concept for simultaneous cell shape and motion analysis in fast microchannel flows by implementing a multiobject feature extraction algorithm on a frame-straddling high-speed vision platform. The system can synchronize two camera inputs with the same view with only a tiny time delay on the sub-microsecond timescale. Real-time video processing is performed in hardware logic by extracting the moment features of multiple cells in 512 \,\times\, 256 images at 4000 fps for the two camera inputs and their frame-straddling time can be adjusted from 0 to 0.25 ms in 9.9 ns steps. By setting the frame-straddling time in a certain range to avoid large image displacements between the two camera inputs, our frame-straddling high-speed vision platform can perform simultaneous shape and motion analysis of cells in fast microchannel flows of 1 m/s or greater. The results of real-time experiments conducted to analyze the deformabilities and velocities of sea urchin egg cells fast-flowing in microchannels verify the efficacy of our vision-based cell analysis system. [ABSTRACT FROM PUBLISHER]

This paper describes a high-frame-rate (HFR) vision system that can extract locations and features of multiple objects in an image at 2000 f/s for 512\,\times\,512 images by implementing a cell-based multiobject feature extraction algorithm as hardware logic on a field-programmable gate array-based high-speed vision platform. In the hardware implementation of the algorithm, 25 higher-order local autocorrelation features of 1024 objects in an image can be simultaneously extracted for multiobject recognition by dividing the image into 8\,\times\,8 cells concurrently with calculation of the zeroth and first-order moments to obtain the sizes and locations of multiple objects. Our developed HFR multiobject extraction system was verified by performing several experiments: tracking for multiple objects rotating at 16 r/s, recognition for multiple patterns projected at 1000 f/s, and recognition for human gestures with quick finger motion. [ABSTRACT FROM PUBLISHER]