• Title/Summary/Keyword: Image Transfer

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Modulation Transfer Function (MTF) Measurement for KOMPSAT EOC image data Using Edge Method

  • Song J. H.;Lee D. H.
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.489-493
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    • 2004
  • The Modulation Transfer Function (MTF) is commonly used to characterize the spatial quality of imaging systems. This work is the attempt to measure the MTF for KOMPSAT EOC using the non-parametric method as ground inputs. The spatial performance of the KOMPSAT EOC was analyzed by edge method while in flight using multi-temporal image data collected over test site in Seoul. The results from this work demonstrate the potential applicability of this method to estimate MTF for high spatial resolution satellite KOMPSAT-2 that is being developed to be launched in 2005.

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Selecting Sound-Field Control Factors in the Image Model Method Using Head-Related Transfer Function (머리전달함수를 이용한 영상 음원법에서 음장 제어 요소 결정)

  • 임정빈
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1998.06d
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    • pp.56-59
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    • 1998
  • 머리전달함수(Head-Related Transfer Function, HRTF)를 이용한 영상 음원법(Image Model Method, IMM)을 적용하여 3차원 음장을 제어하기 위한 요소결정 방법을 제안한다. 제어 요소들은 직방체 내부에서의 음 에너지에 관한 이론을 토대로 결정하였다. 각 제어요소를 3차원 음장 모델에 적용하고, 헤드폰을 사용하여 청취자에 의한 심리음향 실험한 결과, 제어된 음장에서는 음상의 두외 정위, 거리감, 공간감이 실내에서와 같이 자연스럽게 형성됨을 나타냈다.

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Multistage Transfer Learning for Breast Cancer Early Diagnosis via Ultrasound (유방암 조기 진단을 위한 초음파 영상의 다단계 전이 학습)

  • Ayana, Gelan;Park, Jinhyung;Choe, Se-woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.05a
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    • pp.134-136
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    • 2021
  • Research related to early diagnosis of breast cancer using artificial intelligence algorithms has been actively conducted in recent years. Although various algorithms that classify breast cancer based on a few publicly available ultrasound breast cancer images have been published, these methods show various limitations such as, processing speed and accuracy suitable for the user's purpose. To solve this problem, in this paper, we propose a multi-stage transfer learning where ResNet model trained on ImageNet is transfer learned to microscopic cancer cell line images, which was again transfer learned to classify ultrasound breast cancer images as benign and malignant. The images for the experiment consisted of 250 breast cancer ultrasound images including benign and malignant images and 27,200 cancer cell line images. The proposed multi-stage transfer learning algorithm showed more than 96% accuracy when classifying ultrasound breast cancer images, and is expected to show higher utilization and accuracy through the addition of more cancer cell lines and real-time image processing in the future.

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A study on velocity measurements of natural convection flows using multiple pulsed particle image analysis (다중노출 입자영상해석을 통한 자연대류 유속측정에 관한 연구)

  • Han, H.T.;Kim, Y.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.9 no.3
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    • pp.268-275
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    • 1997
  • Using the film-based particle image velocimetry, natural convective flows have been measured quantitatively in a rectangular enclosure with a heater located on the bottom surface. The success rate of the present interrogation method has been obtained as a function of the number of particle pairs and the distance between the particle pairs. The influence of the diffraction halo at the center have been effectively eliminated by rotating-subtracting the original Fourier-transformed image. By utilizing the coded multiple pulsed illumination with two different time intervals, the minimum measurable velocity have been improved. The results of the velocity distributions and the heat transfer correlations have been obtained for different locations of heater in the enclosure.

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Attentive Transfer Learning via Self-supervised Learning for Cervical Dysplasia Diagnosis

  • Chae, Jinyeong;Zimmermann, Roger;Kim, Dongho;Kim, Jihie
    • Journal of Information Processing Systems
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    • v.17 no.3
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    • pp.453-461
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    • 2021
  • Many deep learning approaches have been studied for image classification in computer vision. However, there are not enough data to generate accurate models in medical fields, and many datasets are not annotated. This study presents a new method that can use both unlabeled and labeled data. The proposed method is applied to classify cervix images into normal versus cancerous, and we demonstrate the results. First, we use a patch self-supervised learning for training the global context of the image using an unlabeled image dataset. Second, we generate a classifier model by using the transferred knowledge from self-supervised learning. We also apply attention learning to capture the local features of the image. The combined method provides better performance than state-of-the-art approaches in accuracy and sensitivity.

Deep Learning-based Professional Image Interpretation Using Expertise Transplant (전문성 이식을 통한 딥러닝 기반 전문 이미지 해석 방법론)

  • Kim, Taejin;Kim, Namgyu
    • Journal of Intelligence and Information Systems
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    • v.26 no.2
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    • pp.79-104
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    • 2020
  • Recently, as deep learning has attracted attention, the use of deep learning is being considered as a method for solving problems in various fields. In particular, deep learning is known to have excellent performance when applied to applying unstructured data such as text, sound and images, and many studies have proven its effectiveness. Owing to the remarkable development of text and image deep learning technology, interests in image captioning technology and its application is rapidly increasing. Image captioning is a technique that automatically generates relevant captions for a given image by handling both image comprehension and text generation simultaneously. In spite of the high entry barrier of image captioning that analysts should be able to process both image and text data, image captioning has established itself as one of the key fields in the A.I. research owing to its various applicability. In addition, many researches have been conducted to improve the performance of image captioning in various aspects. Recent researches attempt to create advanced captions that can not only describe an image accurately, but also convey the information contained in the image more sophisticatedly. Despite many recent efforts to improve the performance of image captioning, it is difficult to find any researches to interpret images from the perspective of domain experts in each field not from the perspective of the general public. Even for the same image, the part of interests may differ according to the professional field of the person who has encountered the image. Moreover, the way of interpreting and expressing the image also differs according to the level of expertise. The public tends to recognize the image from a holistic and general perspective, that is, from the perspective of identifying the image's constituent objects and their relationships. On the contrary, the domain experts tend to recognize the image by focusing on some specific elements necessary to interpret the given image based on their expertise. It implies that meaningful parts of an image are mutually different depending on viewers' perspective even for the same image. So, image captioning needs to implement this phenomenon. Therefore, in this study, we propose a method to generate captions specialized in each domain for the image by utilizing the expertise of experts in the corresponding domain. Specifically, after performing pre-training on a large amount of general data, the expertise in the field is transplanted through transfer-learning with a small amount of expertise data. However, simple adaption of transfer learning using expertise data may invoke another type of problems. Simultaneous learning with captions of various characteristics may invoke so-called 'inter-observation interference' problem, which make it difficult to perform pure learning of each characteristic point of view. For learning with vast amount of data, most of this interference is self-purified and has little impact on learning results. On the contrary, in the case of fine-tuning where learning is performed on a small amount of data, the impact of such interference on learning can be relatively large. To solve this problem, therefore, we propose a novel 'Character-Independent Transfer-learning' that performs transfer learning independently for each character. In order to confirm the feasibility of the proposed methodology, we performed experiments utilizing the results of pre-training on MSCOCO dataset which is comprised of 120,000 images and about 600,000 general captions. Additionally, according to the advice of an art therapist, about 300 pairs of 'image / expertise captions' were created, and the data was used for the experiments of expertise transplantation. As a result of the experiment, it was confirmed that the caption generated according to the proposed methodology generates captions from the perspective of implanted expertise whereas the caption generated through learning on general data contains a number of contents irrelevant to expertise interpretation. In this paper, we propose a novel approach of specialized image interpretation. To achieve this goal, we present a method to use transfer learning and generate captions specialized in the specific domain. In the future, by applying the proposed methodology to expertise transplant in various fields, we expected that many researches will be actively conducted to solve the problem of lack of expertise data and to improve performance of image captioning.

Evaluation of Transfer Learning in Gastroscopy Image Classification using Convolutional Neual Network (합성곱 신경망을 활용한 위내시경 이미지 분류에서 전이학습의 효용성 평가)

  • Park, Sung Jin;Kim, Young Jae;Park, Dong Kyun;Chung, Jun Won;Kim, Kwang Gi
    • Journal of Biomedical Engineering Research
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    • v.39 no.5
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    • pp.213-219
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    • 2018
  • Stomach cancer is the most diagnosed cancer in Korea. When gastric cancer is detected early, the 5-year survival rate is as high as 90%. Gastroscopy is a very useful method for early diagnosis. But the false negative rate of gastric cancer in the gastroscopy was 4.6~25.8% due to the subjective judgment of the physician. Recently, the image classification performance of the image recognition field has been advanced by the convolutional neural network. Convolutional neural networks perform well when diverse and sufficient amounts of data are supported. However, medical data is not easy to access and it is difficult to gather enough high-quality data that includes expert annotations. So This paper evaluates the efficacy of transfer learning in gastroscopy classification and diagnosis. We obtained 787 endoscopic images of gastric endoscopy at Gil Medical Center, Gachon University. The number of normal images was 200, and the number of abnormal images was 587. The image size was reconstructed and normalized. In the case of the ResNet50 structure, the classification accuracy before and after applying the transfer learning was improved from 0.9 to 0.947, and the AUC was also improved from 0.94 to 0.98. In the case of the InceptionV3 structure, the classification accuracy before and after applying the transfer learning was improved from 0.862 to 0.924, and the AUC was also improved from 0.89 to 0.97. In the case of the VGG16 structure, the classification accuracy before and after applying the transfer learning was improved from 0.87 to 0.938, and the AUC was also improved from 0.89 to 0.98. The difference in the performance of the CNN model before and after transfer learning was statistically significant when confirmed by T-test (p < 0.05). As a result, transfer learning is judged to be an effective method of medical data that is difficult to collect good quality data.

A Study on Image Creation and Modification Techniques Using Generative Adversarial Neural Networks (생성적 적대 신경망을 활용한 부분 위변조 이미지 생성에 관한 연구)

  • Song, Seong-Heon;Choi, Bong-Jun;Moon, M-Ikyeong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.2
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    • pp.291-298
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    • 2022
  • A generative adversarial network (GAN) is a network in which two internal neural networks (generative network and discriminant network) learn while competing with each other. The generator creates an image close to reality, and the delimiter is programmed to better discriminate the image of the constructor. This technology is being used in various ways to create, transform, and restore the entire image X into another image Y. This paper describes a method that can be forged into another object naturally, after extracting only a partial image from the original image. First, a new image is created through the previously trained DCGAN model, after extracting only a partial image from the original image. The original image goes through a process of naturally combining with, after re-styling it to match the texture and size of the original image using the overall style transfer technique. Through this study, the user can naturally add/transform the desired object image to a specific part of the original image, so it can be used as another field of application for creating fake images.

A Normalized Loss Function of Style Transfer Network for More Diverse and More Stable Transfer Results (다양성 및 안정성 확보를 위한 스타일 전이 네트워크 손실 함수 정규화 기법)

  • Choi, Insung;Kim, Yong-Goo
    • Journal of Broadcast Engineering
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    • v.25 no.6
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    • pp.980-993
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    • 2020
  • Deep-learning based style transfer has recently attracted great attention, because it provides high quality transfer results by appropriately reflecting the high level structural characteristics of images. This paper deals with the problem of providing more stable and more diverse style transfer results of such deep-learning based style transfer method. Based on the investigation of the experimental results from the wide range of hyper-parameter settings, this paper defines the problem of the stability and the diversity of the style transfer, and proposes a partial loss normalization method to solve the problem. The style transfer using the proposed normalization method not only gives the stability on the control of the degree of style reflection, regardless of the input image characteristics, but also presents the diversity of style transfer results, unlike the existing method, at controlling the weight of the partial style loss, and provides the stability on the difference in resolution of the input image.