Interactive image manipulation for surgical planning

The Australian e-Health Research Centre in collaboration with the Queensland University of Technology's Paediatric Spine Research Group is developing software for visualisation and manipulation of large three-dimensional (3D) medical image data sets. The software allows the extraction of anatomical data from individual patients for use in preoperative planning. State-of-the-art computer technology makes it possible to slice through the image dataset at any angle, or manipulate 3D representations of the data instantly. Although the software was initially developed to support planning for scoliosis surgery, it can be applied to any dataset whether obtained from computed tomography, magnetic resonance imaging or any other imaging modality.

A verification system for cinematographer image generation tools

The Production Workstation developed at the University of Greenwich is evaluated as a tool for assisting all those concerned with production. It enables the producer, director, and cinematographer to explore the quality of the images obtainable when using a plethora of tools. Users are free to explore many possible choices, ranging from 35mm to DV, and combine them with the many image manipulation tools of the cinematographer. The validation required for the system is explicitly examined, concerning the accuracy of the resulting imagery. Copyright © 1999 by the Society of Motion Picture and Television Engineers, Inc.

Measurements of simulated periodontal bone defects in inverted digital image and film-based radiograph: An in vitro study

Purpose: This study was performed to compare the inverted digital images and film-based images of dry pig mandibles to measure the periodontal bone defect depth. Materials and Methods: Forty 2-wall bone defects were made in the proximal region of the premolar in the dry pig mandibles. The digital and conventional radiographs were taken using a Schick sensor and Kodak F-speed intraoral film. Image manipulation (inversion) was performed using Adobe Photoshop 7.0 software. Four trained examiners made all of the radiographic measurements in millimeters a total of three times from the cementoenamel junction to the most apical extension of the bone loss with both types of images: inverted digital and film. The measurements were also made in dry mandibles using a periodontal probe and digital caliper. The Student's t-test was used to compare the depth measurements obtained from the two types of images and direct visual measurement in the dry mandibles. A significance level of 0.05 for a 95% confidence interval was used for each comparison. Results: There was a significant difference between depth measurements in the inverted digital images and direct visual measurements (p>|t|=0.0039), with means of 6.29 mm (IC95%:6.04-6.54) and 6.79 mm (IC95%:6.45-7.11), respectively. There was a non-significant difference between the film-based radiographs and direct visual measurements (p>|t|=0.4950), with means of 6.64mm (IC95%:6.40-6.89) and 6.79mm(IC95%:6.45-7.11), respectively. Conclusion: The periodontal bone defect measurements in the inverted digital images were inferior to film-based radiographs, underestimating the amount of bone loss. copy; 2012 by Korean Academy of Oral and Maxillofacial Radiology.

Assessment of using digital manipulation tools for diagnosing mandibular radiolucent lesions

Objective: The purpose of this study was to analyse the use of digital tools for image enhancement of mandibular radiolucent lesions and the effects of this manipulation on the percentage of correct radiographic diagnoses. Methods: 24 panoramic radiographs exhibiting radiolucent lesions were selected, digitized and evaluated by non-experts (undergraduate and newly graduated practitioners) and by professional experts in oral diagnosis. The percentages of correct and incorrect diagnoses, according to the use of brightness/contrast, sharpness, inversion, highlight and zoom tools, were compared. All dental professionals made their evaluations without (T-1) and with (T-2) a list of radiographic diagnostic parameters. Results: Digital tools were used with low frequency mainly in T-2. The most preferred tool was sharpness (45.2%). In the expert group, the percentage of correct diagnoses did not change when any of the digital tools were used. For the non-expert group, there was an increase in the frequency of correct diagnoses when brightness/contrast was used in T-2 (p = 0.008) and when brightness/contrast and sharpness were not used in T-1 (p = 0.027). The use or non-use of brightness/contrast, zoom and sharpness showed moderate agreement in the group of experts [kappa agreement coefficient (kappa) = 0.514, 0.425 and 0.335, respectively]. For the non-expert group there was slight agreement for all the tools used (kappa <= 0.237). Conclusions: Consulting the list of radiographic parameters before image manipulation reduced the frequency of tool use in both groups of examiners. Consulting the radiographic parameters with the use of some digital tools was important for improving correct diagnosis only in the group of non-expert examiners. Dentomaxillofacial Radiology (2012) 41, 203-210. doi: 10.1259/dmfr/78567773

A Type System For Safe SN Resource Allocation

snBench is a platform on which novice users compose and deploy distributed Sense and Respond programs for simultaneous execution on a shared, distributed infrastructure. It is a natural imperative that we have the ability to (1) verify the safety/correctness of newly submitted tasks and (2) derive the resource requirements for these tasks such that correct allocation may occur. To achieve these goals we have established a multi-dimensional sized type system for our functional-style Domain Specific Language (DSL) called Sensor Task Execution Plan (STEP). In such a type system data types are annotated with a vector of size attributes (e.g., upper and lower size bounds). Tracking multiple size aspects proves essential in a system in which Images are manipulated as a first class data type, as image manipulation functions may have specific minimum and/or maximum resolution restrictions on the input they can correctly process. Through static analysis of STEP instances we not only verify basic type safety and establish upper computational resource bounds (i.e., time and space), but we also derive and solve data and resource sizing constraints (e.g., Image resolution, camera capabilities) from the implicit constraints embedded in program instances. In fact, the static methods presented here have benefit beyond their application to Image data, and may be extended to other data types that require tracking multiple dimensions (e.g., image "quality", video frame-rate or aspect ratio, audio sampling rate). In this paper we present the syntax and semantics of our functional language, our type system that builds costs and resource/data constraints, and (through both formalism and specific details of our implementation) provide concrete examples of how the constraints and sizing information are used in practice.

Estudo de Funcionalidades HTML5 para um Editor de Imagem na Internet

Hoje em dia existem múltiplas aplicações multimédia na Internet, sendo comum qualquer website apresentar mais de uma forma de visualização de informação além do texto como, por exemplo: imagens, áudio, vídeo e animação. Com aumento do consumo e utilização de Smartphone e Tablets, o volume de tráfego de internet móvel tem vindo a crescer rapidamente, bem como o acesso à internet através da televisão. As aplicações web-based ganham maior relevância devido à maior partilha ou consumo de conteúdos multimédia, com ou sem edição ou manipulação da mesma, através de redes sociais, como o Facebook. Neste documento é apresentado o estudo de alternativas HTML5 e a implementação duma aplicação web-based no âmbito do Mestrado de Engenharia Informática, ramo de Sistemas Gráficos e Multimédia, no Instituto Superior Engenharia do Porto (ISEP). A aplicação tem como objetivo a edição e manipulação de imagens, tanto em desktop como em dispositivos móveis, sendo este processo exclusivamente feito no lado do cliente, ou seja, no Browser do utilizador. O servidor é usado somente para o armazenamento da aplicação. Durante o desenvolvimento do projeto foi realizado um estudo de soluções de edição e manipulação de imagem existentes no mercado, com a respetiva análise de comparação e apresentadas tecnologias Web modernas como HTML5, CSS3 e JavaScript, que permitirão desenvolver o protótipo. Posteriormente, serão apresentadas, detalhadamente, as várias fases do desenvolvimento de um protótipo, desde a análise do sistema, à apresentação do protótipo e indicação das tecnologias utilizadas. Também serão apresentados os resultados dos inquéritos efetuados a um grupo de pessoas que testaram esse protótipo. Finalmente, descrever-se-á de forma mais exaustiva, a implementação e serão apontadas dificuldades encontradas ao longo do desenvolvimento, bem como indicadas futuras melhorias a introduzir.

Soft computing in biometrics : a pragmatic appraisal

The ever increasing spurt in digital crimes such as image manipulation, image tampering, signature forgery, image forgery, illegal transaction, etc. have hard pressed the demand to combat these forms of criminal activities. In this direction, biometrics - the computer-based validation of a persons' identity is becoming more and more essential particularly for high security systems. The essence of biometrics is the measurement of person’s physiological or behavioral characteristics, it enables authentication of a person’s identity. Biometric-based authentication is also becoming increasingly important in computer-based applications because the amount of sensitive data stored in such systems is growing. The new demands of biometric systems are robustness, high recognition rates, capability to handle imprecision, uncertainties of non-statistical kind and magnanimous flexibility. It is exactly here that, the role of soft computing techniques comes to play. The main aim of this write-up is to present a pragmatic view on applications of soft computing techniques in biometrics and to analyze its impact. It is found that soft computing has already made inroads in terms of individual methods or in combination. Applications of varieties of neural networks top the list followed by fuzzy logic and evolutionary algorithms. In a nutshell, the soft computing paradigms are used for biometric tasks such as feature extraction, dimensionality reduction, pattern identification, pattern mapping and the like.

Metamorphic epiphany -- 3D animation

As far back as I can remember, I have always been interested in studio art. Whether it be painting, drawing, printmaking, or photography, it has consistently been a part of my life. Upon enrolling in Colby, I became interested in computers and decided to major my undergraduate college career in Computer Science. Not forgetting past interests, I continued my studio art education, taking several classes within the Art department. In due time, I began combining interests and began studying Computer Graphics and Design. With limited resources in this field at Colby, the majority of my computer graphic education and experience has been done on my own time apart from regular classroom work. As time progressed, so did my interests. Starting with simple image manipulation of digitally scanned photographs, I moved on to Web Page design, eventually leading to Desktop Publishing. Ultimately, I wanted to take a step further and expand my overall computer graphic knowledge by learning 3D modeling and animation. With even fewer resources in 3D animation at Colby, I perceived having trouble finding the information and tools I would need to gain the necessary skills for this new field. The Senior Scholars program gave me the opponunity to find and acquire the necessary tools to pursue my interest. This program also allowed me to devote the proper amount of time required for learning these new tools.

Comparison between embossed digital imaging and unprocessed film-based radiography in detecting periodontal bone defects: an in vitro study

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Quanto de desvio da linha média dentária superior ortodontistas e leigos conseguem perceber?

OBJETIVOS: avaliar o grau de percepção do desvio de linha média superior e da angulação incisal do arco superior entre ortodontistas e leigos, assim como a influência da visualização clínica do filtro labial como referência morfológica para esse diagnóstico. MÉTODOS: foi utilizada a fotografia do sorriso de um indivíduo do gênero feminino, na qual foram produzidas alterações na linha média dentária, de 1 em 1 milímetro, até 4mm, e na angulação incisal, de 5 em 5 graus, até 15 graus, ambas para o lado esquerdo, com o auxílio de um programa de manipulação de imagens (Adobe Photoshop 7.0®).As imagens obtidas foram recortadas,formando um grupo com e outro sem a visualização do filtro labial e,em seguida,foram organizadas aleatoriamente e avaliadas por 24 ortodontistas e 24 indivíduos leigos com nível superior. RESULTADOS: os resultados obtidos revelaram que os ortodontistas foram capazes de detectar desvios da linha média a partir de 2mm (p < 0,05) e da angulação incisal a partir de 5 graus (p < 0,05), enquanto leigos só detectaram como inaceitáveis desvios a partir de 3 ou 4mm (dependendo da presença do filtro labial na imagem analisada) e 10 graus de alteração angular dos incisivos. A visualização do filtro labial na fotografia influenciou, embora suavemente, somente a avaliação dos examinadores leigos. CONCLUSÕES: conclui-se, portanto, que ortodontistas são mais críticos a pequenas variações da linha média superior e da angulação incisal do que indivíduos leigos,e que a visualização do filtro labial superior tem importância secundária como elemento de diagnóstico do desvio da linha média superior para leigos.

The ability of orthodontists and laypeople in the perception of gradual reduction of dentogingival exposure while smiling

OBJETIVO: avaliar a diferença na percepção de ortodontistas e leigos quanto à redução da exposição dentogengival no sorriso. MÉTODOS: no total, 60 avaliadores de ambos os sexos (30 leigos e 30 ortodontistas) avaliaram fotografias do sorriso espontâneo de dois indivíduos, um do sexo masculino e um do feminino. A partir das imagens originais, a altura do sorriso foi modificada usando-se um programa de manipulação de imagens. Os examinadores emitiram notas de 0 a 10, conforme o nível de agradabilidade. A reprodutibilidade do método foi examinada através do teste de Wilcoxon, enquanto os testes de Friedman e Wilcoxon (P<0,05) foram utilizados para observar as diferenças intra e interexaminadores, respectivamente. RESULTADOS: os resultados demonstraram não haver diferença entre os grupos de avaliadores com relação à estética quando a altura de ambos os sorrisos foi modificada. Entretanto, o sorriso do indivíduo do sexo masculino teve menor aceitabilidade do que o sorriso feminino. Uma suave redução na exposição dentogengival no sorriso (2mm) não foi percebida por leigos ou ortodontistas (p>0,05). CONCLUSÃO: o sorriso do indivíduo do sexo feminino recebeu notas mais altas do que o do masculino; entretanto, amostras envolvendo um maior número de indivíduos em cada grupo são necessárias para confirmar se a observação estaria relacionada ao sexo do indivíduo examinado.

Perception of the esthetic impact of mandibular incisor extraction treatment on laypersons, dental professionals, and dental students

Objective: To evaluate the degree of perception of laypersons, dental professionals, and dental students regarding dental esthetics in cases with mandibular central incisor extraction. Materials and Methods: Using a smile photograph of a person with normal occlusion and all teeth, modifications were made to reflect the extraction of a mandibular incisor of various compositions and sizes. For this purpose a program specifically for image manipulation (Adobe Photoshop CS3, Adobe Systems Inc) was used. After manipulation the images were printed on photographic paper, attached to a questionnaire and distributed to laypersons, dental professionals, and dental students (n = 90) to evaluate the degree of perception and esthetic using a scale of attractiveness, where 0 = hardly attractive, 5 = attractive, and 10 = very attractive. The differences between examiners were checked by the Mann-Whitney test. All the statistics were performed with a confidence level of 95%. Results: The results demonstrated the skill of the dental professionals and dental students in perceiving the difference between cases of normal occlusion and cases where an incisor was lacking (P < .05). The photograph in which the lateral incisors were shown to be larger than the central incisor was the one that obtained the highest value among the cases of extraction in all groups of evaluators. Conclusions: It can be concluded that dental professionals and dental students are more skillful at identifying deviation from normality. In addition, central incisor extraction should always be discarded when there are other treatment options available. (Angle Orthod. 2012;82:732-738.)

A integração e compreensão do desenho na modelação 3D : enquadramento académico

Na medida em que os produtos e os processos de criação são cada vez mais mediados digitalmente, existe uma reflexão recente acerca da relação entre as imagens e as ferramentas usadas para a sua produção. A relação natural e estreita entre a dimensão conceptual e a dimensão física abre a discussão ao nível da semântica e dos processos da projetação e manipulação das imagens, nas quais estão naturalmente incluídas as ferramentas CAD. Tendo o desenho um papel inequívoco e fundamental no exercício da projetação e da modelação 3D é pertinente perceber a relação e a articulação entre estas duas ferramentas. Reconhecendo o desenho como uma ferramenta de domínio físico capaz de expressar o pensamento que opera a transformação de concepções abstratas em concepções concretas, reconhecê-lo refletido na dimensão virtual através de um software CAD 3D não é trivial, já que este, na generalidade, é processado através de um pensamento cujo contexto é distante da materialidade. Metodologicamente, abordaremos esta questão procurando a verificação da hipótese através de uma proposta de exercício prático que procura avaliar o efeito que as imagens analógicas poderão ter sobre o reconhecimento e operatividade da ferramenta Blender num enquadramento académico. Pretende-se, pois, perceber como o desenho analógico pode integrar o processo de modelação 3D e qual a relação que mantém com quem elas opera. A articulação do desenho com as ferramentas de produção de design, especificamente CAD 3D, permitirá compreender na especialidade a articulação entre ferramentas de diferentes naturezas tanto no processo da projetação quanto na criação de artefactos visuais. Assim como poderá lançar a discussão acerca das estratégias pedagógicas de ensino do desenho e do 3D num curso de Design.