Solid Texture Synthesis and Mapping of Liver for Virtual Surgery

Chen Si-Xi,Li Jian-Wei,Chen Guo-Dong 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.12

In order to see clearly the details inside the liver and enhance the users’ visual presence in the virtual surgery simulation system, the principles and methods of solid texture are used to render the photorealistic liver. Firstly, the sample sets are processed and multiple samples are used to synthesize the liver solid texture. Secondly, to improving the mapping efficiency of graphics hardware, the texture atlas is used to map the solid texture. In order to improve the fill rate of texture atlas, the height descending triangle bounding box method is used. The experimental result shows that the internal texture can be observed clearly. The study is of great significance to the photorealistic rendering of virtual liver surgery system, and provides a guideline for the solid texture synthesis and mapping of other human organs.

A Research on 3D Texture Production Using Artificial Intelligence Softwear

마카,정진헌 한국인터넷방송통신학회 2023 International Journal of Internet, Broadcasting an Vol.15 No.4

AI image generation technology has become a popular research direction in the field of AI, which is widely used in the field of digital art and conceptual design, and can also be used in the process of 3D texture mapping. This paper introduces the production process of 3D texture mapping using AI image technology, and discusses whether it can be used as a new way of 3D texture mapping to enrich the 3D texture mapping production process. Two AI deep learning models, Stable Diffusion and Midjourney, were combined to generate high-quality AI textures. Finally, the lmage to material function of substance 3D Sampler was used to convert the AI-generated textures into PBR 3D texture maps. And applied in 3D environment. This study shows that 3D texture maps generated by AI image generation technology can be used in 3D environment, which not only has short production time and high production efficiency, but also has rich changes in map styles, which can be quickly adjusted and modified according to the design scheme. However, some AI texture maps need to be manually modified before they can be used. With the continuous development of AI technology, there will be great potential for further development and innovation of AI-generated image technology in the 3D content production process in the future.

UAV 비행경로에 따른 3D Mapping 데이터 유효성 비교

신용승,전경식,이병길 한국산학기술학회 2022 한국산학기술학회논문지 Vol.23 No.6

Unmanned aerial vehicles (UAVs) are increasingly used because they are suitable for small-scale fieldwork, such as urban landscape analysis and old downtown documenting projects. Along these lines, this study proposed a UAV imaging method for more effective use of UAV in 3D data generation for small-scale sites. The study area was Singhil-dong, Ansan-si, South Korea, which was photographed using the DJI Mavic 2 Pro UAV by the study. In particular, the actual angle of view of the UAV camera was analyzed through the experiment of the study, and the optimal photographing specifications were derived through a simulation of the study area. The photographing specifications derived were a photoshooting angle of 75°, photography overlap of 95%, and UAV flight altitude of 60m. With the derived photographing specifications, 400 images of the study area were captured under a grid and circular flight paths for the UAV, respectively. Subsequently, 3D modeling and texture mapping of the study area were performed from the captured images using Reality Capture, a 3D mapping software. In particular, the number of triangular faces in the 3D model and texture map was limited to 500,000. Further, analyzing the 3D model and texture map of the study area showed that the lower part of any building in the study area was accurately modeled and rendered, and the respective size of the triangular faces was uniform under the circular flight path for the UAV. On the other hand, the lower part of the buildings with narrow spacing each was inaccurately modeled and rendered, and the respective size of the triangular faces was non-uniform (confirming that the overall 3D mapping quality was relatively poor) under the grid flight path for the UAV. UAV(Unmanned Aerial Vehicle)는 도심 경관성 분석, 구도심기록화사업 등의 소규모 현장 작업에 적합하여 활용이 늘어나고 있다. 본 연구에서는 소규모 현장에서 3D 데이터 취득을 더욱 유효하게 활용하기 위한 UAV 촬영 방법을 제안하고자 하였다. DJI사의 Mavic 2pro를 사용하여 안산시 신길동의 대상지역을 촬영하였다. 실험을 통하여 카메라의 실제 화각을 분석하고, 이를 대상지역에 적용하는 모의 실험을 통해 최적의 촬영조건을 도출하였다. 도출된 촬영 제원은 촬영각도 75°, 중복도 95%, 촬영고도 60m이다. 도출된 촬영 제원으로 격자 비행과 원주 비행으로 동일하게 400매의 사진을 획득하였다. 3D mapping 소프트웨어인 Reality Capture를 사용하여 획득된 사진으로부터 3D 모델링과 texture mapping을 시행하였다. 3D 모델링 결과 triangle face는 500,000개로 제한하였다. 최종 결과물을 비교해 본 결과 원주 비행에서는 건물의 하단부가 명확하게 모델링되고 rendering 되었으며, 전체적으로 triangle face의 크기도 균일하게 나타났다. 반면 격자 비행에서는 인동거리가 좁은 건물 사이에서 건물 하단부의 모델링이 부정확하게 나타났으며, triangle face의 크기도 불균일하여 전체적인 mapping의 품질이 상대적으로 좋지 않음을 확인할 수 있었다.

디지털 트윈에 기반한 Texture Mapping 최적화 연구

정은철,배재훈,이병도,배윤경,김준택 국제차세대융합기술학회 2024 차세대융합기술학회논문지 Vol.8 No.1

제조업을 포함한 다양한 산업 분야에서 디지털 트윈을 활용하여 사업적인 운용 성능을 극대화하고 있다. 그러나 건축 분야의 디지털 트윈은 표현하고자 하는 공간의 범위가 매우 넓기 때문에 필요한 데이터 양도 증가하게 되어 디지털 트윈 구현에 어려움이 있지만, 이를 최적화하는 방식을 통해 그 효과를 높이고 있다. 이에 본 연구는 디지털 트윈 기술을 사용하여 실제의 건물을 스캔하고 이로부터 생성된 데이터의 Texture mapping 오차를최적화하는 방법을 제안한다. 이를 통해 기존의 가상공간과는 다른 메타버스 플랫폼의 기반구축과 그 특징을 알아보고자 한다. Leica RTC360, 3D Scanner, Metrix Camera, Drone으로 스캔한 실제의 섬과 건물 내부, 외부의XR 데이터를 디지털 트윈과 접목해 생산한 후, LoD(Level of Detail)를 적용한 최적화 과정을 거쳐 시각화하였다. 결과적으로 최적화된 디지털 트윈 Mesh와 Texture Mapping을 활용해 더욱 생동감 있는 메타 아일랜드 플랫폼을 구축할 수 있으며, 이는 가상공간 속에서 콘텐츠의 다양성을 높이는 기회 요소로 작용할 것이다. 이는 새로운 사용자층의 형성과 그에 따른 사용자 간의 상호작용을 촉진하여 공동체적 유대감 형성에 효과를 낼 것이다. Digital twins are used to maximize business operational performance in various industries, including manufacturing. However, since the digital twin in the architecture field has a very wide range of spaces to be expressed, the amount of data required increases, making it difficult to implement the digital twin, but it is increasing its effectiveness through optimization. Therefore, This study proposes a method of scanning real buildings using digital twins and optimizing the texture mapping error of the generated data, and through this, a meta bus platform base different from the existing virtual space is established and its characteristics are investigated. Accordingly, the actual island, inside, and outside XR data scanned with Trimble TX8, 3D Scanner, Metrix Camera, and Drone were produced by combining them with digital twins, and then visualized by applying LoD (Level of Detail) to optimize them. As a result, a more lively meta-island platform can be built by optimizing the texture mapping process using digital twins, and as an opportunity factor to increase the diversity of content in virtual space, it will contribute to the formation of a new user layer and the resulting interaction between users.

Depth Occlusion을 이용한 멀티플 프로젝티브 텍스처 매핑

박재욱(Jae Wook Park),김윤정(Yun Jung Kim) 한국애니메이션학회 2015 애니메이션연구 Vol.11 No.1

프로젝티브 텍스처 매핑은 사진 텍스처를 이용해서 3D 장면을 손쉽게 사실적으로 만들 수 있는 효과적인 방식이다. 하지만 프로젝션 카메라 시점에서 겹쳐 보이는 면에서는 같은 이미지가 중복되어 매핑이 된다는 문제점 때문에 국내 애니메이션 업계에서는 많이 쓰이지 않는다. 이 논문에서는 좌표계 변환에 의해 작동되는 프로젝티브 텍스처 매핑의 구조를 살펴보고 이에 의한 문제점을 분석한 후, 중복되어 매핑되는 문제점을 해결하기 위한 방법을 제시한다. 이 방법은 프로젝션 카메라와 오브젝트의 셰이딩 포인트(shading point)까지의 거리를 계산하되, 한 번은 프로젝션 카메라 시점에서 계산해서 Depth 맵으로 만든 후에 지오메트리에 프로젝티브 텍스처 매핑으로 입혀서 렌더 카메라 시점에서 추출하고, 다른 한 번은 그냥 렌더 카메라 시점에서 계산을 해서 두 Depth 이미지의 차이를 비교해서 중복되었는지 아닌지 판단하는 것이다. 이렇게 추출된 Depth Occlusion 이용해서 중복 현상을 없애고, 그 결과 생긴 비어 있는 공간을 다른 시각의 프로젝티브 텍스처 매핑을 추가하여 채워 넣는 방법을 제시한다. Projective texture mapping is an efficient method that can make realistic 3D image by using picture image. However, Projective texture mapping is not very popular for the Animation industry because the texture pass through the geometry and be mapped into all backface. This study is intended to identify the structure of project texture mapping that operates based on the conversion of coordinates, analyze the problems from it, and suggest solution on duplicated mapping. This method calculates the distances up to shading point between projection camera and object. One time, it calculates them in a perspective of projection camera making them as a map to apply projective texture mapping on the geometry to extract in a perspective of render camera afterwards. At another time, it calculates in a perspective of render camera comparing the distance between two images and determining if they are duplicated. Hereupon, it is intended to suggest a method that uses extracted masks to remove duplicated image adding the projective texture mapping on the vacate areas in a different perspective.

광선 추적법 텍스쳐 매핑을 위한 MIP-Map 수준 선택 알고리즘 연구

박우찬,김동석 한국게임학회 2010 한국게임학회 논문지 Vol.10 No.4

본 논문은 광선 추적법 텍스쳐 매핑에서 MIP-Map 알고리즘 사용 시 텍스쳐 이미지들의 MIP-Map 수준을 선택하는 효과적인 방식을 제안한다. 이는 렌더링 시 물체와 교차하는 광선의 길이만을 사용하여 해당 물체의 텍스쳐 MIP-Map 수준을 선택하는 방법이다. 본 방식은 MIP-Map을 지원하지 않는 방식에 비하여 텍스쳐 알리아싱 면에서 우수하고 성능 저하는 미비하다. This paper proposes an effective method to select MIP-Map level of texture images for ray-traced texture mapping. This MIP-Map level selection method requires only the total length of intersected ray. By supporting MIP-Map for texture mapping, we can reduce the texture aliasing effects, while our approach decreases rendering performance very slightly.

GPU를 이용한 Gabor Texture 특징점 기반의 금속 패드 변색 분류 알고리즘

최학남(Xue-Nan Cui),박은수(Eun-soo Park),김준철(Jun-Chul Kim),김학일(Hakil Kim) 제어로봇시스템학회 2009 제어·로봇·시스템학회 논문지 Vol.15 No.8

This paper presents a Gabor texture feature extraction method for classification of discolored Metal pad images using GPU(Graphics Processing Unit). The proposed algorithm extracts the texture information using Gabor filters and constructs a pattern map using the extracted information. Finally, the golden pad images are classified by utilizing the feature vectors which are extracted from the constructed pattern map. Tn order to evaluate the performance of the Gabor texture feature extraction algorithm based on GPU, a sequential processing and parallel processing using Open MP in GPU of this algorithm were adopted. Also, the proposed algorithm was implemented by using Global memory and Shared memory in GPU. The experimental results were demonstrated that the method using Shared memory in GPU provides the best performance. For evaluating the effectiveness of extracted Gabor texture features, an experimental validation has been conducted on a database of 20 Metal pad images and the experiment has shown no mis-classification.

노이즈 함수 및 높이맵을 이용한 3차원 지형 메쉬의 생성

박상근,Sangkun, Park 한국교통대학교 융복합기술연구소 2022 융ㆍ복합기술연구소 논문집 Vol.12 No.1

This paper describes an algorithm for generating a terrain using a noise function and a height map as one of the procedural terrain generation methods. The polygon mesh data structure to represent the generated terrain concisely and render it is also described. The Perlin noise function is used as the noise technique for terrain mesh, and the height data of the terrain is generated by combining the four noise waves. In addition, the terrain height information can be also obtained from actual image data taken from the satellite. The algorithm presented in this paper generates the geometry part of the polygon topography from the height data obtained, and generated a material for texture mapping with two textures, that is, a diffuse texture and a normal texture. The validity of the terrain method proposed in this paper is verified through application examples, and its possibility can be confirmed through performance verification.

TOF 깊이 카메라와 DSLR을 이용한 복합형 카메라 시스템 구성 방법

김수현(Soohyeon Kim),김재인(Jae-In Kim),김태정(Taejung Kim) 한국방송·미디어공학회 2014 방송공학회논문지 Vol.19 No.4

This paper presents a method for a hybrid (color and depth) camera system construction using a photogrammetric technology. A TOF depth camera is efficient since it measures range information of objects in real-time. However, there are some problems of the TOF depth camera such as low resolution and noise due to surface conditions. Therefore, it is essential to not only correct depth noise and distortion but also construct the hybrid camera system providing a high resolution texture map for generating a 3D model using the depth camera. We estimated geometry of the hybrid camera using a traditional relative orientation algorithm and performed texture mapping using backward mapping based on a condition of collinearity. Other algorithm was compared to evaluate performance about the accuracy of a model and texture mapping. The result showed that the proposed method produced the higher model accuracy.

고해상도 텍스처 맵 생성을 위한 딥러닝 기반 초해상도 기법들의 비교 분석 연구

김혜주,나재호 (사)한국컴퓨터그래픽스학회 2023 컴퓨터그래픽스학회논문지 Vol.29 No.5

디스플레이의 해상도의 증가에 따라 고해상도 텍스처 맵을 내장한 앱들도 함께 증가하는 추세에 있다. 최근 딥러닝 기반이미지 초해상도 기법들의 발전은 이러한 고해상도 텍스처 생성 작업을 자동화할 수 있는 가능성을 만들고 있다. 하지만이러한 적용 사례에 대해 심층적으로 분석한 연구는 아직 부족한 상태이다. 그래서 본 논문에서는 최신 초해상도 기법들중 BSRGAN, Real-ESRGAN, SwinIR(classical 및 real-world image SR)을 택하여 텍스처 맵의 업스케일링(upscaling)에 적용한 후 그 결과를 정량적, 정성적으로 비교, 분석하였다. 실험 결과 업스케일링 후 나타나는 다양한 아티팩트(artifact)들을발견할 수 있었으며, 이를 통해 기존 초해상도 기법들을 텍스처 맵 업스케일링에 곧바로 적용하기에는 일부 미흡한 부분이존재한다는 점을 확인하였다. As display resolution increases, many apps also tend to include high-resolution texture maps. Recent advancements in deeplearning-based image super-resolution techniques make it possible to automate high-resolution texture generation. However, there is still a lack of comprehensive analysis of the application of these techniques to texture maps. In this paper, we selected three recent super-resolution techniques, namely BSRGAN, Real-ESRGAN, and SwinIR (classical and real-world image SR), and applied them to upscale texture maps. We then conducted a quantitative and qualitative analysis of the experimental results. The findings revealed various artifacts after upscaling, which indicates that there are still limitations in directly applying superresolution techniques to texture-map upscaling