Computed Tomography(CT)is a commonly used technology in Printed Circuit Boards(PCB)non-destructive testing,and element segmentation of CT images is a key subsequent step.With the development of deep learning,researche...Computed Tomography(CT)is a commonly used technology in Printed Circuit Boards(PCB)non-destructive testing,and element segmentation of CT images is a key subsequent step.With the development of deep learning,researchers began to exploit the“pre-training and fine-tuning”training process for multi-element segmentation,reducing the time spent on manual annotation.However,the existing element segmentation model only focuses on the overall accuracy at the pixel level,ignoring whether the element connectivity relationship can be correctly identified.To this end,this paper proposes a PCB CT image element segmentation model optimizing the semantic perception of connectivity relationship(OSPC-seg).The overall training process adopts a“pre-training and fine-tuning”training process.A loss function that optimizes the semantic perception of circuit connectivity relationship(OSPC Loss)is designed from the aspect of alleviating the class imbalance problem and improving the correct connectivity rate.Also,the correct connectivity rate index(CCR)is proposed to evaluate the model’s connectivity relationship recognition capabilities.Experiments show that mIoU and CCR of OSPC-seg on our datasets are 90.1%and 97.0%,improved by 1.5%and 1.6%respectively compared with the baseline model.From visualization results,it can be seen that the segmentation performance of connection positions is significantly improved,which also demonstrates the effectiveness of OSPC-seg.展开更多
Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective...Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective way of sorting.Owing to significant domain gaps between natural images and kitchen waste images,it is difficult to reflect the characteristics of diverse scales and dense distribution in kitchen waste based on an ImageNet pre-trained model,leading to poor generalisation.In this article,the authors propose the first pre-trained model for kitchen waste sorting called KitWaSor,which combines both contrastive learning(CL)and masked image modelling(MIM)through self-supervised learning(SSL).First,to address the issue of diverse scales,the authors propose a mixed masking strategy by introducing an incomplete masking branch based on the original random masking branch.It prevents the complete loss of small-scale objects while avoiding excessive leakage of large-scale object pixels.Second,to address the issue of dense distribution,the authors introduce semantic consistency constraints on the basis of the mixed masking strategy.That is,object semantic reasoning is performed through semantic consistency constraints to compensate for the lack of contextual information.To train KitWaSor,the authors construct the first million-level kitchen waste dataset across seasonal and regional distributions,named KWD-Million.Extensive experiments show that KitWaSor achieves state-of-the-art(SOTA)performance on the two most relevant downstream tasks for kitchen waste sorting(i.e.image classification and object detection),demonstrating the effectiveness of the proposed KitWaSor.展开更多
Masked autoencoders(MAEs)have recently achieved great success in computer vision.They can automatically extract representations from unlabeled data and improve the performance of various downstream tasks.However,train...Masked autoencoders(MAEs)have recently achieved great success in computer vision.They can automatically extract representations from unlabeled data and improve the performance of various downstream tasks.However,training an MAE model requires substantial resources,which limits their accessibility to many academic institutions:often laboratories in universities lack the necessary resources.This issue significantly hinders the development of this field.In this paper,we propose FastMAE,an efficient MAE approach.Inspired by the idea of offline tokenizers in natural language processing,FastMAE presents a novel way to build an offline vision tokenizer,which can provide high-level semantics in an efficient way.Benefiting from the offline tokenizer,FastMAE becomes an efficient vision learner.Our experiments demonstrate that FastMAE can achieve 83.6%accuracy with ViT-B in only 18.8 h on 8 NVIDIA Tesla-V100 GPUs,which is 31.3×faster than the original MAE,providing a resource friendly baseline for the computer vision community.Moreover,it also achieves comparable performance to state-of-the-art methods.We hope our research will attract more people to engage in MAE-related research and that we can advance its development together.展开更多
文摘Computed Tomography(CT)is a commonly used technology in Printed Circuit Boards(PCB)non-destructive testing,and element segmentation of CT images is a key subsequent step.With the development of deep learning,researchers began to exploit the“pre-training and fine-tuning”training process for multi-element segmentation,reducing the time spent on manual annotation.However,the existing element segmentation model only focuses on the overall accuracy at the pixel level,ignoring whether the element connectivity relationship can be correctly identified.To this end,this paper proposes a PCB CT image element segmentation model optimizing the semantic perception of connectivity relationship(OSPC-seg).The overall training process adopts a“pre-training and fine-tuning”training process.A loss function that optimizes the semantic perception of circuit connectivity relationship(OSPC Loss)is designed from the aspect of alleviating the class imbalance problem and improving the correct connectivity rate.Also,the correct connectivity rate index(CCR)is proposed to evaluate the model’s connectivity relationship recognition capabilities.Experiments show that mIoU and CCR of OSPC-seg on our datasets are 90.1%and 97.0%,improved by 1.5%and 1.6%respectively compared with the baseline model.From visualization results,it can be seen that the segmentation performance of connection positions is significantly improved,which also demonstrates the effectiveness of OSPC-seg.
基金National Key Research and Development Program of China,Grant/Award Number:2021YFC1910402。
文摘Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective way of sorting.Owing to significant domain gaps between natural images and kitchen waste images,it is difficult to reflect the characteristics of diverse scales and dense distribution in kitchen waste based on an ImageNet pre-trained model,leading to poor generalisation.In this article,the authors propose the first pre-trained model for kitchen waste sorting called KitWaSor,which combines both contrastive learning(CL)and masked image modelling(MIM)through self-supervised learning(SSL).First,to address the issue of diverse scales,the authors propose a mixed masking strategy by introducing an incomplete masking branch based on the original random masking branch.It prevents the complete loss of small-scale objects while avoiding excessive leakage of large-scale object pixels.Second,to address the issue of dense distribution,the authors introduce semantic consistency constraints on the basis of the mixed masking strategy.That is,object semantic reasoning is performed through semantic consistency constraints to compensate for the lack of contextual information.To train KitWaSor,the authors construct the first million-level kitchen waste dataset across seasonal and regional distributions,named KWD-Million.Extensive experiments show that KitWaSor achieves state-of-the-art(SOTA)performance on the two most relevant downstream tasks for kitchen waste sorting(i.e.image classification and object detection),demonstrating the effectiveness of the proposed KitWaSor.
基金supported by the National Science and Technology Major Project(Grant No.2021ZD0112902)the National Natural Science Foundation of China(Grant Nos.623B2057 and 62220106003)+1 种基金Tsinghua University Initiative Scientific Research ProgramTsinghua-Tencent Joint Laboratory for Internet Innovation Technology.
文摘Masked autoencoders(MAEs)have recently achieved great success in computer vision.They can automatically extract representations from unlabeled data and improve the performance of various downstream tasks.However,training an MAE model requires substantial resources,which limits their accessibility to many academic institutions:often laboratories in universities lack the necessary resources.This issue significantly hinders the development of this field.In this paper,we propose FastMAE,an efficient MAE approach.Inspired by the idea of offline tokenizers in natural language processing,FastMAE presents a novel way to build an offline vision tokenizer,which can provide high-level semantics in an efficient way.Benefiting from the offline tokenizer,FastMAE becomes an efficient vision learner.Our experiments demonstrate that FastMAE can achieve 83.6%accuracy with ViT-B in only 18.8 h on 8 NVIDIA Tesla-V100 GPUs,which is 31.3×faster than the original MAE,providing a resource friendly baseline for the computer vision community.Moreover,it also achieves comparable performance to state-of-the-art methods.We hope our research will attract more people to engage in MAE-related research and that we can advance its development together.