Slides by Amaia Salvador at the UPC Computer Vision Reading Group.
Source document on GDocs with clickable links:
https://docs.google.com/presentation/d/1jDTyKTNfZBfMl8OHANZJaYxsXTqGCHMVeMeBe5o1EL0/edit?usp=sharing
Based on the original work:
Ren, Shaoqing, Kaiming He, Ross Girshick, and Jian Sun. "Faster R-CNN: Towards real-time object detection with region proposal networks." In Advances in Neural Information Processing Systems, pp. 91-99. 2015.
Intro to selective search for object proposals, rcnn family and retinanet state of the art model deep dives for object detection along with MAP concept for evaluating model and how does anchor boxes make the model learn where to draw bounding boxes
I mede this slide for the beginners of object detection.
Anchor box was really hard to understand for me, so I wrote about it as easy to understand as I can.
Let's overwhelmingly prosper!!
Slides by Amaia Salvador at the UPC Computer Vision Reading Group.
Source document on GDocs with clickable links:
https://docs.google.com/presentation/d/1jDTyKTNfZBfMl8OHANZJaYxsXTqGCHMVeMeBe5o1EL0/edit?usp=sharing
Based on the original work:
Ren, Shaoqing, Kaiming He, Ross Girshick, and Jian Sun. "Faster R-CNN: Towards real-time object detection with region proposal networks." In Advances in Neural Information Processing Systems, pp. 91-99. 2015.
Intro to selective search for object proposals, rcnn family and retinanet state of the art model deep dives for object detection along with MAP concept for evaluating model and how does anchor boxes make the model learn where to draw bounding boxes
I mede this slide for the beginners of object detection.
Anchor box was really hard to understand for me, so I wrote about it as easy to understand as I can.
Let's overwhelmingly prosper!!
https://telecombcn-dl.github.io/2017-dlcv/
Deep learning technologies are at the core of the current revolution in artificial intelligence for multimedia data analysis. The convergence of large-scale annotated datasets and affordable GPU hardware has allowed the training of neural networks for data analysis tasks which were previously addressed with hand-crafted features. Architectures such as convolutional neural networks, recurrent neural networks and Q-nets for reinforcement learning have shaped a brand new scenario in signal processing. This course will cover the basic principles and applications of deep learning to computer vision problems, such as image classification, object detection or image captioning.
In this presentation we discuss the convolution operation, the architecture of a convolution neural network, different layers such as pooling etc. This presentation draws heavily from A Karpathy's Stanford Course CS 231n
Presentation for the Berlin Computer Vision Group, December 2020 on deep learning methods for image segmentation: Instance segmentation, semantic segmentation, and panoptic segmentation.
In some applications, the output of the system is a sequence of actions. In such a case, a single action is not important
game playing where a single move by itself is not that important.in the case of the agent acts on its environment, it receives some evaluation of its action (reinforcement),
but is not told of which action is the correct one to achieve its goal
Object Detection using Deep Neural NetworksUsman Qayyum
Recent Talk at PI school covering following contents
Object Detection
Recent Architecture of Deep NN for Object Detection
Object Detection on Embedded Computers (or for edge computing)
SqueezeNet for embedded computing
TinySSD (object detection for edge computing)
A comprehensive tutorial on Convolutional Neural Networks (CNN) which talks about the motivation behind CNNs and Deep Learning in general, followed by a description of the various components involved in a typical CNN layer. It explains the theory involved with the different variants used in practice and also, gives a big picture of the whole network by putting everything together.
Next, there's a discussion of the various state-of-the-art frameworks being used to implement CNNs to tackle real-world classification and regression problems.
Finally, the implementation of the CNNs is demonstrated by implementing the paper 'Age ang Gender Classification Using Convolutional Neural Networks' by Hassner (2015).
Recent Progress on Object Detection_20170331Jihong Kang
This slide provides a brief summary of recent progress on object detection using deep learning.
The concept of selected previous works(R-CNN series/YOLO/SSD) and 6 recent papers (uploaded to the Arxiv between Dec/2016 and Mar/2017) are introduced in this slide.
Most papers are focusing on improving the performance of small object detection.
CNN has become an important part of deep learning networks. It has become crucial to get the in-depth knowledge on CNN. This ppt gives a brief overview on CNN.
Locating objects in images (“detection”) quickly and efficiently enables object tracking and counting applications on embedded visual sensors (fixed and mobile). By 2012, progress on techniques for detecting objects in images – a topic of perennial interest in computer vision – had plateaued, and techniques based on histogram of oriented gradients (HOG) were state of the art. Soon, though, convolutional neural networks (CNNs), in addition to classifying objects, were also beginning to become effective at simultaneously detecting objects. Research in CNN-based object detection was jump-started by the groundbreaking region-based CNN (R-CNN). We’ll follow the evolution of neural network algorithms for object detection, starting with R-CNN and proceeding to Fast R-CNN, Faster R-CNN, “You Only Look Once” (YOLO), and up to the latest Single Shot Multibox detector. In this talk, we’ll examine the successive innovations in performance and accuracy embodied in these algorithms – which is a good way to understand the insights behind effective neural-network-based object localization. We’ll also contrast bounding-box approaches with pixel-level segmentation approaches and present pros and cons.
https://telecombcn-dl.github.io/2017-dlcv/
Deep learning technologies are at the core of the current revolution in artificial intelligence for multimedia data analysis. The convergence of large-scale annotated datasets and affordable GPU hardware has allowed the training of neural networks for data analysis tasks which were previously addressed with hand-crafted features. Architectures such as convolutional neural networks, recurrent neural networks and Q-nets for reinforcement learning have shaped a brand new scenario in signal processing. This course will cover the basic principles and applications of deep learning to computer vision problems, such as image classification, object detection or image captioning.
In this presentation we discuss the convolution operation, the architecture of a convolution neural network, different layers such as pooling etc. This presentation draws heavily from A Karpathy's Stanford Course CS 231n
Presentation for the Berlin Computer Vision Group, December 2020 on deep learning methods for image segmentation: Instance segmentation, semantic segmentation, and panoptic segmentation.
In some applications, the output of the system is a sequence of actions. In such a case, a single action is not important
game playing where a single move by itself is not that important.in the case of the agent acts on its environment, it receives some evaluation of its action (reinforcement),
but is not told of which action is the correct one to achieve its goal
Object Detection using Deep Neural NetworksUsman Qayyum
Recent Talk at PI school covering following contents
Object Detection
Recent Architecture of Deep NN for Object Detection
Object Detection on Embedded Computers (or for edge computing)
SqueezeNet for embedded computing
TinySSD (object detection for edge computing)
A comprehensive tutorial on Convolutional Neural Networks (CNN) which talks about the motivation behind CNNs and Deep Learning in general, followed by a description of the various components involved in a typical CNN layer. It explains the theory involved with the different variants used in practice and also, gives a big picture of the whole network by putting everything together.
Next, there's a discussion of the various state-of-the-art frameworks being used to implement CNNs to tackle real-world classification and regression problems.
Finally, the implementation of the CNNs is demonstrated by implementing the paper 'Age ang Gender Classification Using Convolutional Neural Networks' by Hassner (2015).
Recent Progress on Object Detection_20170331Jihong Kang
This slide provides a brief summary of recent progress on object detection using deep learning.
The concept of selected previous works(R-CNN series/YOLO/SSD) and 6 recent papers (uploaded to the Arxiv between Dec/2016 and Mar/2017) are introduced in this slide.
Most papers are focusing on improving the performance of small object detection.
CNN has become an important part of deep learning networks. It has become crucial to get the in-depth knowledge on CNN. This ppt gives a brief overview on CNN.
Locating objects in images (“detection”) quickly and efficiently enables object tracking and counting applications on embedded visual sensors (fixed and mobile). By 2012, progress on techniques for detecting objects in images – a topic of perennial interest in computer vision – had plateaued, and techniques based on histogram of oriented gradients (HOG) were state of the art. Soon, though, convolutional neural networks (CNNs), in addition to classifying objects, were also beginning to become effective at simultaneously detecting objects. Research in CNN-based object detection was jump-started by the groundbreaking region-based CNN (R-CNN). We’ll follow the evolution of neural network algorithms for object detection, starting with R-CNN and proceeding to Fast R-CNN, Faster R-CNN, “You Only Look Once” (YOLO), and up to the latest Single Shot Multibox detector. In this talk, we’ll examine the successive innovations in performance and accuracy embodied in these algorithms – which is a good way to understand the insights behind effective neural-network-based object localization. We’ll also contrast bounding-box approaches with pixel-level segmentation approaches and present pros and cons.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2022/08/understanding-dnn-based-object-detectors-a-presentation-from-au-zone-technologies/
Azhar Quddus, Senior Computer Vision Engineer at Au-Zone Technologies, presents the “Understanding DNN-Based Object Detectors” tutorial at the May 2022 Embedded Vision Summit.
Unlike image classifiers, which merely report on the most important objects within or attributes of an image, object detectors determine where objects of interest are located within an image. Consequently, object detectors are central to many computer vision applications including (but not limited to) autonomous vehicles and virtual reality.
In this presentation, Quddus provides a technical introduction to deep-neural-network-based object detectors. He explains how these algorithms work, and how they have evolved in recent years, utilizing examples of popular object detectors. Quddus examines some of the trade-offs to consider when selecting an object detector for an application, and touches on accuracy measurement. He also discusses performance comparison among the models discussed in this presentation.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2023/11/understanding-selecting-and-optimizing-object-detectors-for-edge-applications-a-presentation-from-walmart-global-tech/
Md Nasir Uddin Laskar, Staff Machine Learning Engineer at Walmart Global Tech, presents the “Understanding, Selecting and Optimizing Object Detectors for Edge Applications” tutorial at the May 2023 Embedded Vision Summit.
Object detectors count objects in a scene and determine their precise locations, while also labeling them. Object detection plays a crucial role in many vision applications, from autonomous driving to smart appliances. In many of these applications, it’s necessary or desirable to implement object detection at the edge.
In this presentation, Laskar explores the evolution of object detection algorithms, from traditional approaches to deep learning-based methods and transformer-based architectures. He delves into widely used approaches for object detection, such as two-stage R-CNNs and one-stage YOLO algorithms, and examines their strengths and weaknesses. And he provides guidance on how to evaluate and select an object detector for an edge application.
Online video object segmentation via convolutional trident networkNAVER Engineering
발표자: 장원동 (고려대 박사과정)
발표일: 2017.8.
개요:
A semi-supervised online video object segmentation algorithm, which accepts user annotations about a target object at the first frame, will be presented. It propagates the segmentation labels at the previous frame to the current frame using optical flow vectors.
However, the propagation is error-prone. Therefore, I’ve developed the convolutional trident network, which has three decoding branches: separative, definite foreground, and definite background decoders.
Then, the algorithm performs Markov random field optimization based on outputs of the three decoders.
These process is sequentially carried out from the second to the last frames to extract a segment track of the target object.
Experimental results will demonstrate that this algorithm significantly outperforms the state-of-the-art conventional algorithms on the DAVIS benchmark dataset.
Localization and classification. Overfeat: class agnostic versu class specific localization, fully convolutional neural networks, greedy merge strategy. Multiobject detection. Region proposal and selective search. R-CNN, Fast R-CNN, Faster R-CNN and YOLO. Image segmentation. Semantic segmentation and transposed convolutions. Instance segmentation and Mask R-CNN. Image captioning. Recurrent Neural Networks (RNNs). Language generation. Long Short Term Memory (LSTMs). DeepImageSent, Show and Tell, and Show, Attend and Tell algorithms.
Slides by Albert Jimenez about the following paper:
Gordo, Albert, Jon Almazan, Jerome Revaud, and Diane Larlus. "Deep Image Retrieval: Learning global representations for image search." arXiv preprint arXiv:1604.01325 (2016).
We propose a novel approach for instance-level image retrieval. It produces a global and compact fixed-length representation for each image by aggregating many region-wise descriptors. In contrast to previous works employing pre-trained deep networks as a black box to produce features, our method leverages a deep architecture trained for the specific task of image retrieval. Our contribution is twofold: (i) we introduce a ranking framework to learn convolution and projection weights that are used to build the region features; and (ii) we employ a region proposal network to learn which regions should be pooled to form the final global descriptor. We show that using clean training data is key to the success of our approach. To that aim, we leverage a large scale but noisy landmark dataset and develop an automatic cleaning approach. The proposed architecture produces a global image representation in a single forward pass. Our approach significantly outperforms previous approaches based on global descriptors on standard datasets. It even surpasses most prior works based on costly local descriptor indexing and spatial verification. We intend to release our pre-trained model.
PR-217: EfficientDet: Scalable and Efficient Object DetectionJinwon Lee
TensorFlow Korea 논문읽기모임 PR12 217번째 논문 review입니다
이번 논문은 GoogleBrain에서 쓴 EfficientDet입니다. EfficientNet의 후속작으로 accuracy와 efficiency를 둘 다 잡기 위한 object detection 방법을 제안한 논문입니다. 이를 위하여 weighted bidirectional feature pyramid network(BiFPN)과 EfficientNet과 유사한 방법의 detection용 compound scaling 방법을 제안하고 있는데요, 자세한 내용은 영상을 참고해주세요
논문링크: https://arxiv.org/abs/1911.09070
영상링크: https://youtu.be/11jDC8uZL0E
#PR12 #PR366
안녕하세요 논문 읽기 모임 PR-12의 366번째 논문리뷰입니다.
올해가 AlexNet이 나온지 10주년이 되는 해네요.
AlexNet이 2012년에 혜성처럼 등장한 이후, Solve computer vision problem = Use CNN이 공식처럼 사용되던 2010년대가 가고
2020년대 들어서 ViT의 등장을 시작으로 Transformer 기반의 network들이 CNN의 자리를 위협하고 상당부분 이미 뺏어간 상황입니다.
2020년대에 CNN의 가야할 길은 어디일까요?
Inductive bias가 적은 Transformer가 대용량의 데이터로 학습하면 항상 CNN보다 더 낫다는 건 진실일까요?
이 논문에서는 2020년대를 위한 CNN이라는 제목으로 ConvNeXt라는 새로운(?) architecture를 제안합니다.
사실 새로운 건 없고 그동안 있었던 것들과 Transformer에서 적용한 것들을 copy해와서 CNN에 적용해보았는데요,
Transformer보다 성능도 좋고 속도도 빠른 결과가 나왔다고 합니다.
결과에 대해서 약간의 논란이 twitter 상에서 나오고 있는데 이 부분 포함해서 자세한 내용은 영상을 통해서 보실 수 있습니다.
늘 재밌게 봐주시고 좋아요 댓글 구독 해주시는 분들께 감사드립니다 :)
논문링크: https://arxiv.org/abs/2201.03545
영상링크: https://youtu.be/Mw7IhO2uBGc
PR-355: Masked Autoencoders Are Scalable Vision LearnersJinwon Lee
#PR12 #PR355
안녕하세요 논문 읽기 모임 PR-12의 355번째 논문리뷰입니다.
Computer Vision 분야에는 왜 BERT나 GPT 같은 model이 없을까요?
Self-supervised learning을 이용하여 pretraining 한 후, downstream task에서 supervised learning보다 성능이 잘나오는 model을 언제쯤 보게 될까요?
어쩌면 그 model 이 논문에 있을 수도 있습니다.
이 논문에서는 ViT 기반의 Autoencoder를 활용하여 ImageNet-1K training set을 이용하여 self-supervised pretraining으로 SOTA(ImageNet-1K only)를 달성하였습니다.
image를 patch로 만들고 75%의 patch를 masking한 후 25%의 patch만으로 masking된 75%의 pixel 값을 직접 예측하는 형태를 사용하였고,
다른 model들에 비하여 연산량과 memory 사용량이 적어서 big model로의 확장도 용이합니다.
재미있는 아이디어와 다양한 실험결과가 있으니 자세한 내용은 발표 영상을 참고해주세요!
영상링크: https://youtu.be/mtUa3AAxPNQ
논문링크: https://arxiv.org/abs/2111.06377v1
PR-344: A Battle of Network Structures: An Empirical Study of CNN, Transforme...Jinwon Lee
#PR12 #PR344
안녕하세요 TensorFlow Korea 논문 읽기 모임 PR-12의 344번째 논문 리뷰입니다.
오늘은 중국과기대와 MSRA에서 나온 A Battle of Network Structures라는 강렬한 제목을 가진 논문입니다.
부제에서 잘 나와있듯이 이 논문은 computer vision에서 CNN, Transformer, MLP에 대해서 같은 환경에서 비교를 통해 어떤 특징들이 있는지를 알아본 논문입니다.
우선 같은 조건에서 실험하기 위하여 SPACH라는 unified framework을 만들고 그 안에 CNN, Transformer, MLP를 넣어서 실험을 합니다.
셋 모두 조건이 잘 갖춰지면 비슷한 성능을 내지만, MLP는 model size가 커지면 overfitting이 발생하고
CNN은 Transformer에 비해서 적은 data에서도 좋은 성능이 나오는 generalization capability가 좋고,
Transformer는 model capacity가 커서 data가 충분하고 연산량도 큰 환경에서 잘한다는 것이 실험의 한가지 결과입니다.
또하나는 global receptive field를 갖는 transformer나 MLP의 경우에도 local한 연산을 하는 local model을 같이 써줄때에 성능이 좋아진다는 것입니다.
이런 insight들을 통해서 이 논문에서는 CNN과 Transformer를 결합한 형태의 Hybrid model을 제안하여 SOTA 성능을 낼 수 있음을 보여줍니다.
개인적으로 놀랄만한 insight를 발견한 것은 아니었지만 세가지 network의 특징과 장단점에 대해서 정리해볼 수 있는 그런 논문이라고 평하고 싶습니다.
자세한 내용은 영상을 참고해주세요! 감사합니다
영상링크: https://youtu.be/NVLMZZglx14
논문링크: https://arxiv.org/abs/2108.13002
PR-330: How To Train Your ViT? Data, Augmentation, and Regularization in Visi...Jinwon Lee
안녕하세요 TensorFlow Korea 논문 읽기 모임 PR-12의 330번째 논문 리뷰입니다.
오늘은 무려 5만개의 학습된 ViT model을 제공하는 구글스러운 논문을 리뷰해보았습니다. ViT가 CNN을 조금씩 대체해가고 있는데요, ViT는 CNN과 달리 inductive bias가 적은 관계로
좋은 성능을 위해서는 굉장히 많은 data가 필요하거나, augmentation과 regularization을 많이 써줘야 합니다.
그런데 이렇게 다양한 경우 즉 다양한 data, 다양한 model size, 다양한 augmentation 방법, 다양한 regularization, 다양한 data size 등등에 따른 ViT의 성능과 속도 등의 비교 분석 실험이 지금까지는 없었죠.
이 논문에서는 그 어려운 걸(?) 해냈습니다. 그리고 수많은 ViT를 이용해 실험을 하면서 몇가지 중요한 finding들을 찾았습니다.
요약하면 다음과 같습니다.
1. augmentation과 regularization을 잘 쓰면 1/10의 data로도 전체 data 다 쓴거랑 대부분 비슷한 성능을 낼 수 있다. 그런데 항상 그런건 아니다.
반대로 말하면 data가 10배 있으면 augmentation이나 regularization안 쓰고도 좋은 성능을 낼 수 있다.
2. downstream task 학습할 때 scratch부터 학습하는거랑 large dataset으로 pre-trained한 걸 이용해서 transfer learning하는 건 후자가 좋다.
3. transfer learning 할 때도 pre-trained model 중에 data 많이 써서 학습한게 더 좋다.
4. augmentation/regularization은 data가 많으면 별 도움이 안되고 둘 중에는 augmenation이 더 좋다.
5. pre-trained model이 많을 때 model을 고르는 방법은 그냥 upstream에서 제일 잘됐던 걸 고르면 얼추 잘된다.
6. 속도를 빠르게 하고 싶을 때는 model을 작은거 쓰지말고 patch size를 키워라. 그래야 성능이 별로 안떨어진다.
입니다.
흥미로운 결과들이 많으니 자세한 내용은 아래 영상을 참고해주세요!
감사합니다!
영상링크: https://youtu.be/A3RrAIx-KCc
논문링크: https://arxiv.org/abs/2106.10270
PR-317: MLP-Mixer: An all-MLP Architecture for VisionJinwon Lee
Computer Vision 분야에서 CNN은 과연 살아남을 수 있을까요?
안녕하세요 TensorFlow Korea 논문 읽기 모임 PR-12의 317번째 논문 리뷰입니다.
이번에는 Google Research, Brain Team의 MLP-Mixer: An all-MLP Architecture for Vision을 리뷰해보았습니다.
Attention의 공격도 버거운데 이번에는 MLP(Multi-Layer Perceptron)의 공격입니다.
MLP만을 사용해서 Image Classification을 하는데 성능도 좋고 속도도 빠르고....
구조를 간단히 소개해드리면 ViT(Vision Transformer)의 self-attention 부분을 MLP로 변경하였습니다.
MLP block 2개를 사용하여 하나는 patch(token)들 간의 연산을 하는데 사용하고, 하나는 patch 내부 연산을 하는데 사용합니다.
사실 MLP를 사용하긴 했지만 논문에도 언급되어 있듯이, 이 부분을 일종의 convolution이라고 볼 수 있는데요...
그래도 transformer 기반의 network이 가질 수밖에 없는 quadratic complexity를 linear로 낮춰주고
convolution의 inductive bias 거의 없이 아주아주 simple한 구조를 활용하여 이렇게 좋은 성능을 보여준 점이 멋집니다.
반면에 역시나 data를 많이 써야 한다거나, MLP의 한계인 fixed length의 input만 받을 수 있다는 점은 단점이라고 생각하는데요,
이 연구를 시작으로 MLP도 다시한번 조명받는 계기가 되면 좋을 것 같네요
비슷한 시점에 나온 비슷한 연구들도 마지막에 간략하게 소개하였습니다.
재미있게 봐주세요. 감사합니다!
논문링크: https://arxiv.org/abs/2105.01601
영상링크: https://youtu.be/KQmZlxdnnuY
PR-297: Training data-efficient image transformers & distillation through att...Jinwon Lee
안녕하세요 TensorFlow Korea 논문 읽기 모임 PR-12의 297번째 리뷰입니다
어느덧 PR-12 시즌 3의 끝까지 논문 3편밖에 남지 않았네요.
시즌 3가 끝나면 바로 시즌 4의 새 멤버 모집이 시작될 예정입니다. 많은 관심과 지원 부탁드립니다~~
(멤버 모집 공지는 Facebook TensorFlow Korea 그룹에 올라올 예정입니다)
오늘 제가 리뷰한 논문은 Facebook의 Training data-efficient image transformers & distillation through attention 입니다.
Google에서 나왔던 ViT논문 이후에 convolution을 전혀 사용하지 않고 오직 attention만을 이용한 computer vision algorithm에 어느때보다 관심이 높아지고 있는데요
이 논문에서 제안한 DeiT 모델은 ViT와 같은 architecture를 사용하면서 ViT가 ImageNet data만으로는 성능이 잘 안나왔던 것에 비해서
Training 방법 개선과 새로운 Knowledge Distillation 방법을 사용하여 mageNet data 만으로 EfficientNet보다 뛰어난 성능을 보여주는 결과를 얻었습니다.
정말 CNN은 이제 서서히 사라지게 되는 것일까요? Attention이 computer vision도 정복하게 될 것인지....
개인적으로는 당분간은 attention 기반의 CV 논문이 쏟아질 거라고 확신하고, 또 여기에서 놀라운 일들이 일어날 수 있을 거라고 생각하고 있습니다
CNN은 10년간 많은 연구를 통해서 발전해왔지만, transformer는 이제 CV에 적용된 지 얼마 안된 시점이라서 더 기대가 크구요,
attention이 inductive bias가 가장 적은 형태의 모델이기 때문에 더 놀라운 이들을 만들 수 있을거라고 생각합니다
얼마 전에 나온 open AI의 DALL-E도 그 대표적인 예라고 할 수 있을 것 같습니다. Transformer의 또하나의 transformation이 궁금하신 분들은 아래 영상을 참고해주세요
영상링크: https://youtu.be/DjEvzeiWBTo
논문링크: https://arxiv.org/abs/2012.12877
PR-284: End-to-End Object Detection with Transformers(DETR)Jinwon Lee
TensorFlow Korea 논문읽기모임 PR12 284번째 논문 review입니다.
이번 논문은 Facebook에서 나온 DETR(DEtection with TRansformer) 입니다.
arxiv-sanity에 top recent/last year에서 가장 상위에 자리하고 있는 논문이기도 합니다(http://www.arxiv-sanity.com/top?timefilter=year&vfilter=all)
최근에 ICLR 2021에 submit된 ViT로 인해서 이제 Transformer가 CNN을 대체하는 것 아닌가 하는 얘기들이 많이 나오고 있는데요, 올 해 ECCV에 발표된 논문이고 feature extraction 부분은 CNN을 사용하긴 했지만 transformer를 활용하여 효과적으로 Object Detection을 수행하는 방법을 제안한 중요한 논문이라고 생각합니다. 이 논문에서는 detection 문제에서 anchor box나 NMS(Non Maximum Supression)와 같은 heuristic 하고 미분 불가능한 방법들이 많이 사용되고, 이로 인해서 유독 object detection 문제는 딥러닝의 철학인 end-to-end 방식으로 해결되지 못하고 있음을 지적하고 있습니다. 그 해결책으로 bounding box를 예측하는 문제를 set prediction problem(중복을 허용하지 않고, 순서에 무관함)으로 보고 transformer를 활용한 end-to-end 방식의 알고리즘을 제안하였습니다. anchor box도 필요없고 NMS도 필요없는 DETR 알고리즘의 자세한 내용이 알고싶으시면 영상을 참고해주세요!
영상링크: https://youtu.be/lXpBcW_I54U
논문링크: https://arxiv.org/abs/2005.12872
PR-270: PP-YOLO: An Effective and Efficient Implementation of Object DetectorJinwon Lee
TensorFlow Korea 논문읽기모임 PR12 270번째 논문 review입니다.
이번 논문은 Baidu에서 나온 PP-YOLO: An Effective and Efficient Implementation of Object Detector입니다. YOLOv3에 다양한 방법을 적용하여 매우 높은 성능과 함께 매우 빠른 속도 두마리 토끼를 다 잡아버린(?) 그런 논문입니다. 논문에서 사용한 다양한 trick들에 대해서 좀 더 깊이있게 살펴보았습니다. Object detection에 사용된 기법 들 중에 Deformable convolution, Exponential Moving Average, DropBlock, IoU aware prediction, Grid sensitivity elimination, MatrixNMS, CoordConv, 등의 방법에 관심이 있으시거나 알고 싶으신 분들은 영상과 발표자료를 참고하시면 좋을 것 같습니다!
논문링크: https://arxiv.org/abs/2007.12099
영상링크: https://youtu.be/7v34cCE5H4k
PR-258: From ImageNet to Image Classification: Contextualizing Progress on Be...Jinwon Lee
TensorFlow Korea 논문읽기모임 PR12 258번째 논문 review입니다.
이번 논문은 MIT에서 나온 From ImageNet to Image Classification: Contextualizing Progress on Benchmarks입니다.
Deep Learning 하시는 분들이면 ImageNet 모르시는 분들이 없을텐데요, 이 논문은 ImageNet의 labeling 방법의 한계와 문제점에 대해서 얘기하고 top-1 accuracy 기반의 평가 방법에도 문제가 있을 수 있음을 지적하고 있습니다.
ImageNet data의 20% 이상이 multi object를 포함하고 있지만 그 중에 하나만 정답으로 인정되는 문제가 있고, annotation 방법의 한계로 인하여 실제로 사람이 생각하는 것과 다른 class가 정답으로 labeling되어 있는 경우도 많았습니다. 또한 terrier만 20종이 넘는 등 전문가가 아니면 판단하기 어려운 label도 많다는 문제도 있었구요. 이 밖에도 다양한 실험을 통해서 정량적인 분석과 함께 human-in-the-loop을 이용한 평가로 현재 model들의 성능이 어디까지 와있는지, 그리고 앞으로 더 높은 성능을 내기 위해서 data labeling 측면에서 해결해야할 과제는 무엇인지에 대해서 이야기하고 있습니다. 논문이 양이 좀 많긴 하지만 기술적인 내용이 별로 없어서 쉽게 읽으실 수 있는데요, 자세한 내용이 궁금하신 분들은 영상을 참고해주세요!
논문링크: https://arxiv.org/abs/2005.11295
발표영상링크: https://youtu.be/CPMgX5ikL_8
TensorFlow Korea 논문읽기모임 PR12 243째 논문 review입니다
이번 논문은 RegNet으로 알려진 Facebook AI Research의 Designing Network Design Spaces 입니다.
CNN을 디자인할 때, bottleneck layer는 정말 좋을까요? layer 수는 많을 수록 높은 성능을 낼까요? activation map의 width, height를 절반으로 줄일 때(stride 2 혹은 pooling), channel을 2배로 늘려주는데 이게 최선일까요? 혹시 bottleneck layer가 없는 게 더 좋지는 않은지, 최고 성능을 내는 layer 수에 magic number가 있는 건 아닐지, activation이 절반으로 줄어들 때 channel을 2배가 아니라 3배로 늘리는 게 더 좋은건 아닌지?
이 논문에서는 하나의 neural network을 잘 design하는 것이 아니라 Auto ML과 같은 기술로 좋은 neural network을 찾을 수 있는 즉 좋은 neural network들이 살고 있는 좋은 design space를 design하는 방법에 대해서 얘기하고 있습니다. constraint이 거의 없는 design space에서 human-in-the-loop을 통해 좋은 design space로 그 공간을 좁혀나가는 방법을 제안하였는데요, EfficientNet보다 더 좋은 성능을 보여주는 RegNet은 어떤 design space에서 탄생하였는지 그리고 그 과정에서 우리가 당연하게 여기고 있었던 design choice들이 잘못된 부분은 없었는지 아래 동영상에서 확인하실 수 있습니다~
영상링크: https://youtu.be/bnbKQRae_u4
논문링크: https://arxiv.org/abs/2003.13678
PR-231: A Simple Framework for Contrastive Learning of Visual RepresentationsJinwon Lee
TensorFlow Korea 논문읽기모임 PR12 231번째 논문 review 입니다
이번 논문은 Google Brain에서 나온 A Simple Framework for Contrastive Learning of Visual Representations입니다. Geoffrey Hinton님이 마지막 저자이시기도 해서 최근에 더 주목을 받고 있는 논문입니다.
이 논문은 최근에 굉장히 핫한 topic인 contrastive learning을 이용한 self-supervised learning쪽 논문으로 supervised learning으로 학습한 ResNet50와 동일한 성능을 얻을 수 있는 unsupervised pre-trainig 방법을 제안하였습니다. Data augmentation, Non-linear projection head, large batch size, longer training, NTXent loss 등을 활용하여 훌륭한 representation learning이 가능함을 보여주었고, semi-supervised learning이나 transfer learning에서도 매우 뛰어난 결과를 보여주었습니다. 자세한 내용은 영상을 참고해주세요
논문링크: https://arxiv.org/abs/2002.05709
영상링크: https://youtu.be/FWhM3juUM6s
PR-207: YOLOv3: An Incremental ImprovementJinwon Lee
TensorFlow Korea 논문읽기모임 PR12 207번째 논문 review입니다
이번 논문은 YOLO v3입니다.
매우 유명한 논문이라서 크게 부연설명이 필요없을 것 같은데요, Object Detection algorithm들 중에 YOLO는 굉장히 특색있는 one-stage algorithm입니다. 이 논문에서는 YOLO v2(YOLO9000) 이후에 성능 향상을 위하여 어떤 것들을 적용하였는지 하나씩 설명해주고 있습니다. 또한 MS COCO의 metric인 average mAP에 대해서 비판하면서 mAP를 평가하는 방법에 대해서도 얘기를 하고 있는데요, 자세한 내용은 영상을 참고해주세요~
논문링크: https://arxiv.org/abs/1804.02767
영상링크: https://youtu.be/HMgcvgRrDcA
PR-197: One ticket to win them all: generalizing lottery ticket initializatio...Jinwon Lee
TensorFlow Korea 논문읽기모임 PR12 197번째 논문 review입니다
(2기 목표 200편까지 이제 3편이 남았습니다)
이번에 제가 발표한 논문은 FAIR(Facebook AI Research)에서 나온 One ticket to win them all: generalizing lottery ticket initializations across datasets and optimizers 입니다
한 장의 ticket으로 모든 복권에서 1등을 할 수 있다면 얼마나 좋을까요?
일반적인 network pruning 방법은 pruning 하기 이전에 학습된 network weight를 그대로 사용하면서 fine tuning하는 방법을 사용해왔습니다
pruning한 이후에 network에 weight를 random intialization한 후 학습하면 성능이 잘 나오지 않는 문제가 있었는데요
작년 MIT에서 나온 Lottery ticket hypothesis라는 논문에서는 이렇게 pruning된 이후의 network를 어떻게 random intialization하면 높은 성능을 낼 수 있는지
이 intialization 방법을 공개하며 lottery ticket의 winning ticket이라고 이름붙였습니다.
그런데 이 winning ticket이 혹시 다른 dataset이나 다른 optimizer를 사용하는 경우에도 잘 동작할 수 있을까요?
예를 들어 CIFAR10에서 찾은 winning ticket이 ImageNet에서도 winning ticket의 성능을 나타낼 수 있을까요?
이 논문은 이러한 질문에 대한 답을 실험을 통해서 확인하였고, initialization에 대한 여러가지 insight를 담고 있습니다.
자세한 내용은 발표 영상을 참고해주세요~!
영상링크: https://youtu.be/YmTNpF2OOjA
발표자료링크: https://www.slideshare.net/JinwonLee9/pr197-one-ticket-to-win-them-all-generalizing-lottery-ticket-initializations-across-datasets-and-optimizers
논문링크: https://arxiv.org/abs/1906.02773
PR-183: MixNet: Mixed Depthwise Convolutional KernelsJinwon Lee
TensorFlow-KR 논문읽기모임 PR12(12PR) 183번째 논문 review입니다.
이번에 살펴볼 논문은 Google Brain에서 발표한 MixNet입니다. Efficiency를 추구하는 CNN에서 depthwise convolution이 많이 사용되는데, 이 때 depthwise convolution filter의 size를 다양하게 해서 성능도 높이고 efficiency도 높이는 방법을 제안한 논문입니다. 자세한 내용은 영상을 참고해주세요
논문링크 : https://arxiv.org/abs/1907.09595
발표영상 : https://youtu.be/252YxqpHzsg
PR-169: EfficientNet: Rethinking Model Scaling for Convolutional Neural NetworksJinwon Lee
TensorFlow-KR 논문읽기모임 PR12 169번째 논문 review입니다.
이번에 살펴본 논문은 Google에서 발표한 EfficientNet입니다. efficient neural network은 보통 mobile과 같은 제한된 computing power를 가진 edge device를 위한 작은 network 위주로 연구되어왔는데, 이 논문은 성능을 높이기 위해서 일반적으로 network를 점점 더 키워나가는 경우가 많은데, 이 때 어떻게 하면 더 효율적인 방법으로 network을 키울 수 있을지에 대해서 연구한 논문입니다. 자세한 내용은 영상을 참고해주세요
논문링크: https://arxiv.org/abs/1905.11946
영상링크: https://youtu.be/Vhz0quyvR7I
PR-155: Exploring Randomly Wired Neural Networks for Image RecognitionJinwon Lee
TensorFlow-KR 논문읽기모임 PR12 155번째 논문 review 입니다.
이번에는 Facebook AI Research에서 최근에 나온(4/2) Exploring Randomly Wired Neural Networks for Image Recognition을 review해 보았습니다. random하게 generation된 network이 그동안 사람들이 온갖 노력을 들여서 만든 network 이상의 성능을 나타낸다는 결과로 많은 사람들에게 충격을 준 논문인데요, 자세한 내용은 자료와 영상을 참고해주세요
논문링크: https://arxiv.org/abs/1904.01569
영상링크: https://youtu.be/NrmLteQ5BC4
PR-144: SqueezeNext: Hardware-Aware Neural Network DesignJinwon Lee
Tensorfkow-KR 논문읽기모임 PR12 144번째 논문 review입니다.
이번에는 Efficient CNN의 대표 중 하나인 SqueezeNext를 review해보았습니다. SqueezeNext의 전신인 SqueezeNet도 같이 review하였고, CNN을 평가하는 metric에 대한 논문인 NetScore에서 SqueezeNext가 1등을 하여 NetScore도 같이 review하였습니다.
논문링크:
SqueezeNext - https://arxiv.org/abs/1803.10615
SqueezeNet - https://arxiv.org/abs/1602.07360
NetScore - https://arxiv.org/abs/1806.05512
영상링크: https://youtu.be/WReWeADJ3Pw
PR095: Modularity Matters: Learning Invariant Relational Reasoning TasksJinwon Lee
Tensorflow-KR 논문읽기모임 95번째 발표영상입니다
Modularity Matters라는 제목으로 visual relational reasoning 문제를 풀 수 있는 방법을 제시한 논문입니다. 기존 CNN들이 이런 문제이 취약함을 보여주고 이를 해결하기 위한 방법을 제시합니다. 관심있는 주제이기도 하고 Bengio 교수님 팀에서 쓴 논문이라서 review 해보았습니다
발표영상: https://youtu.be/dAGI3mlOmfw
논문링크: https://arxiv.org/abs/1806.06765
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Generating a custom Ruby SDK for your web service or Rails API using Smithyg2nightmarescribd
Have you ever wanted a Ruby client API to communicate with your web service? Smithy is a protocol-agnostic language for defining services and SDKs. Smithy Ruby is an implementation of Smithy that generates a Ruby SDK using a Smithy model. In this talk, we will explore Smithy and Smithy Ruby to learn how to generate custom feature-rich SDKs that can communicate with any web service, such as a Rails JSON API.
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Encryption in Microsoft 365 - ExpertsLive Netherlands 2024Albert Hoitingh
In this session I delve into the encryption technology used in Microsoft 365 and Microsoft Purview. Including the concepts of Customer Key and Double Key Encryption.
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Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
4. History(?) of R-CNN
• Rich feature hierarchies for accurate object detection and
semantic segmentation(2013)
• Fast R-CNN(2015)
• Faster R-CNN: Towards Real-Time Object Detection with
Region Proposal Networks(2015)
• Mask R-CNN(2017)
5. Is Faster R-CNN Really Fast?
• Generally R-FCN and SSD
models are faster on
average while Faster R-
CNN models are more
accurate
• Faster R-CNN models can
be faster if we limit the
number of regions
proposed
8. Region Proposals – Selective Search
• Bottom-up segmentation, merging regions at multiple scales
Convert
regions to
boxes
9. R-CNN Training
• Pre-train a ConvNet(AlexNet) for ImageNet classification dataset
• Fine-tune for object detection(softmax + log loss)
• Cache feature vectors to disk
• Train post hoc linear SVMs(hinge loss)
• Train post hoc linear bounding-box regressors(squared loss)
“Post hoc” means the parameters are learned after
the ConvNet is fixed
10. Bounding-Box Regression
specifies the pixel coordinates of the center of proposal Pi’s
bounding box together with Pi’s width and height in pixels
means the ground-truth bounding box
12. Problems of R-CNN
• Slow at test-time: need to run full forward path of CNN for
each region proposal
13s/image on a GPU(K40)
53s/image on a CPU
• SVM and regressors are post-hoc: CNN features not updated
in response to SVMs and regressors
• Complex multistage training pipeline (84 hours using K40
GPU)
Fine-tune network with softmax classifier(log loss)
Train post-hoc linear SVMs(hinge loss)
Train post-hoc bounding-box regressions(squared loss)
13. Fast R-CNN
• Fix most of what’s wrong with R-CNN and SPP-net
• Train the detector in a single stage, end-to-end
No caching features to disk
No post hoc training steps
• Train all layers of the network
17. RoI Pooling
RoI in Conv feature map : 21x14 3x2 max pooling with stride(3, 2) output : 7x7
RoI in Conv feature map : 35x42 5x6 max pooling with stride(5, 6) output : 7x7
VGG-16
18. Training & Testing
1. Takes an input and a set of bounding boxes
2. Generate convolutional feature maps
3. For each bbox, get a fixed-length feature vector from RoI
pooling layer
4. Outputs have two information
K+1 class labels
Bounding box locations
• Loss function
19. R-CNN vs SPP-net vs Fast R-CNN
Runtime dominated by
region proposals!
20. Problems of Fast R-CNN
• Out-of-network region proposals are the test-time
computational bottleneck
• Is it fast enough??
21. Faster R-CNN(RPN + Fast R-CNN)
• Insert a Region Proposal
Network (RPN) after the last
convolutional layer using GPU!
• RPN trained to produce region
proposals directly; no need for
external region proposals
• After RPN, use RoI Pooling and
an upstream classifier and bbox
regressor just like Fast R-CNN
23. 3 x 3
RPN
• Slide a small window on the
feature map
• Build a small network for
Classifying object or not-object
Regressing bbox locations
• Position of the sliding window
provides localization information
with reference to the image
• Box regression provides finer
localization information with
reference to this sliding window
ZF : 256-d, VGG : 512-d
24. RPN
• Use k anchor boxes at each
location
• Anchors are translation
invariant: use the same ones at
every location
• Regression gives offsets from
anchor boxes
• Classification gives the
probability that each
(regressed) anchor shows an
object
26. Anchors as references
• Anchors: pre-defined reference boxes
• Multi-scale/size anchors:
Multiple anchors are used at each position:
3 scale(128x128, 256x256, 512x512) and 3 aspect rations(2:1, 1:1, 1:2) yield 9
anchors
Each anchor has its own prediction function
Single-scale features, multi-scale predictions
27. Positive/Negative Samples
• An anchor is labeled as positive if
The anchor is the one with highest IoU overlap with a ground-truth
box
The anchor has an IoU overlap with a ground-truth box higher than
0.7
• Negative labels are assigned to anchors with IoU lower than
0.3 for all ground-truth boxes
• 50%/50% ratio of positive/negative anchors in a minibatch
34. Is It Enough?
• RoI Pooling has some quantization operations
• These quantizations introduce misalignments between the RoI
and the extracted features
• While this may not impact classification, it can make a
negative effect on predicting bbox
36. Mask R-CNN
• Mask R-CNN extends Faster R-CNN by adding a branch for
predicting segmentation masks on each Region of Interest
(RoI), in parallel with the existing branch for classification and
bounding box regression
37. Loss Function, Mask Branch
• The mask branch has a K x m x m - dimensional output for
each RoI, which encodes K binary masks of resolution m × m,
one for each of the K classes.
• Applying per-pixel sigmoid
• For an RoI associated with ground-truth class k, Lmask is only
defined on the k-th mask
38. RoI Align
• RoI Align don’t use quantization of the RoI boundaries
• Bilinear interpolation is used for computing the exact values
of the input features