Hyung-Il Kim

Mr. Hyung-Il Kim

Electronics and Telecommunications Research Institute (ETRI)
orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2021
Verified
Conference Paper
Closed access
SLSangmin Lee
Sangmin Lee
HKHak Gu Kim
Hak Gu Kim
DCDae Hwi Choi
Dae Hwi Choi
HKHyung-Il Kim
Hyung-Il Kim
YRYong Man Ro
Yong Man Ro
Our work addresses long-term motion context issues for predicting future frames. To predict the future precisely, it is required to capture which long-term motion context (e.g., walking or running) the input motion (e.g., leg movement) belongs to. The bottlenecks arising when dealing with the long-term motion context are: (i) how to predict the long-term motion context naturally matching input sequences with limited dynamics, (ii) how to predict the long-term motion context with high-dimensionality (e.g., complex motion). To address the issues, we propose novel motion context-aware video prediction. To solve the bottle-neck (i), we introduce a long-term motion context memory (LMC-Memory) with memory alignment learning. The pro-posed memory alignment learning enables to store long-term motion contexts into the memory and to match them with sequences including limited dynamics. As a result, the long-term context can be recalled from the limited in-put sequence. In addition, to resolve the bottleneck (ii), we propose memory query decomposition to store local motion context (i.e., low-dimensional dynamics) and recall the suitable local context for each local part of the input individually. It enables to boost the alignment effects of the memory. Experimental results show that the proposed method outperforms other sophisticated RNN-based methods, especially in long-term condition. Further, we validate the effectiveness of the proposed network designs by conducting ablation studies and memory feature analysis. The source code of this work is available † .

22 October 2024 in IEEE Transactions on Pattern Analysis and Machine Intelligence
Verified
Journal Article
Closed access
MKMinsu Kim
Minsu Kim
HKHyung-Il Kim
Hyung-Il Kim
YRYong Man Ro
Yong Man Ro
Visual Speech Recognition (VSR) aims to infer speech into text depending on lip movements alone. As it focuses on visual information to model the speech, its performance is inherently sensitive to personal lip appearances and movements, and this makes the VSR models show degraded performance when they are applied to unseen speakers. In this paper, to remedy the performance degradation of the VSR model on unseen speakers, we propose prompt tuning methods of Deep Neural Networks (DNNs) for speaker-adaptive VSR. Specifically, motivated by recent advances in Natural Language Processing (NLP), we finetune prompts on adaptation data of target speakers instead of modifying the pre-trained model parameters. Different from the previous prompt tuning methods mainly limited to Transformer variant architecture, we explore different types of prompts, the addition, the padding, and the concatenation form prompts that can be applied to the VSR model which is composed of CNN and Transformer in general. With the proposed prompt tuning, we show that the performance of the pre-trained VSR model on unseen speakers can be largely improved by using a small amount of adaptation data (e.g., less than 5 minutes), even if the pre-trained model is already developed with large speaker variations. Moreover, by analyzing the performance and parameters of different types of prompts, we investigate when the prompt tuning is preferred over the finetuning methods. The effectiveness of the proposed method is evaluated on both word- and sentence-level VSR databases, LRW-ID and GRID.

12 May 2023 in IEEE Transactions on Image Processing
Verified
Journal Article
Closed access
JKJung Uk Kim
Jung Uk Kim
HKHyung-Il Kim
Hyung-Il Kim
YRYong Man Ro
Yong Man Ro
Monocular 3D object detection has drawn increasing attention in various human-related applications, such as autonomous vehicles, due to its cost-effective property. On the other hand, a monocular image alone inherently contains insufficient information to infer the 3D information. In this paper, we propose a new monocular 3D object detector that can recall the stereoscopic visual information about an object, given a left-view monocular image. Here, we devise a location embedding module to handle each object by being aware of its location. Next, given the object appearance of the left-view monocular image, we devise Monocular-to-Stereoscopic (M2S) memory that can recall the object appearance of the right-view and depth information. For this purpose, we introduce a stereoscopic vision memorizing loss that guides the M2S memory to store the stereoscopic visual information. Furthermore, we propose a binocular vision association loss to guide the M2S memory that can associate the information of the left-right view about the object when estimating the depth. As a result, our monocular 3D object detector with the M2S memory can effectively exploit the recalled stereoscopic visual information in the inference phase. The comprehensive experimental results on two public datasets, KITTI 3D Object Detection Benchmark and Waymo Open Dataset, demonstrate the effectiveness of the proposed method. We claim that our method is a step-forward method that follows the behaviors of humans that can recall the stereoscopic visual information even when one eye is closed.

1 September 2015
Verified
Conference Paper
Closed access
HKHyung-Il Kim
Hyung-Il Kim
SLSeung Ho Lee
Seung Ho Lee
MYMan Ro Yong
Man Ro Yong
Considerable research efforts have been made for face recognition in various real-world applications. However, degraded face images, acquired in the real-world, make face recognition difficult. In this paper, we propose a new face image quality assessment that aims to realize a robust and reliable face recognition system. The proposed method considers two factors for face image quality, i.e., visual quality and mismatch between training and test face images. A face image quality assessor is learned based on the two factors to discriminate useful faces from unuseful ones. The proposed face image quality assessment model is robust and adaptive to face recognition systems by employing a learned assessment. Our experimental results on a challenging database show significant improvement in face recognition accuracy by the proposed method.

1 February 2017 in Image and Vision Computing
Verified
Journal Article
Closed access
JSJeong-Jik Seo
Jeong-Jik Seo
HKHyung-Il Kim
Hyung-Il Kim
WNWesley De Neve
Wesley De Neve
YRYong Man Ro
Yong Man Ro

12 February 2023
Verified
Book Chapter
Closed access
PDF file
YLYoungwan Lee
Youngwan Lee
JHJoong-Won Hwang
Joong-Won Hwang
HKHyung-Il Kim
Hyung-Il Kim
KYKimin Yun
Kimin Yun
YKYongjin Kwon
Yongjin Kwon
Sung Ju HwangSung Ju Hwang
Sung Ju Hwang