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Computer Graphic and Animation
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I am working on animation teaching strategy and would like to make my videos myself rather than outsourcing so as to save cost.
Kindly recommend any free app, software, etc pls.
Thank you.
Interested dear
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How to convert 3D model to parametric surface?
I have bunny mesh with vertices(array(5197*3)) and faces(array(10390*3)), how to convert it to parametric surface such as
a=1; b=1; c=1;
u=linspace(-2,2,256);
v=linspace(0,2*pi,256);
[u,v]=meshgrid(u,v);
% Calculate x, y,a dn z at each pair % (u, v) in the grid.
x=a*cosh(u).*cos(v);
y=b*cosh(u).*sin(v);
z=c*sinh(u);
Best way would be to use Surface Mesh Parametrisation package of CGAL C++ library. It has got various examples as well. For your purpose I think square mesh parameterisation suits the best.
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It is well known that the study of computer vision includes acquiring knowledge from images and videos in general. One of its application include deriving 3D information from 2D images.
I would like to know whether the use of 3D imaging from IR cameras be considered in the computer vision field as well. Or is it better suited to be called a Machine Vision application instead?
IR and Visible Imaging are both of them full part of Computer Vision field. All topics of Visible Stereo Imaging applies to IR Stereo Imaging (feature point/contour detection, feature tracking, 3D Reconstruction from image sequences and so on...) . Neverthless, some computer vision techniques have to be specifically tuned/adapted to address IR applications.
Some sample references are available by following:
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Hi together,
when I worked in Roy Sambles' Thin Films & Interfaces Group in Exeter in 1993 I used an existing Fortran program for multilayer Fresnel modelling and improved its slo-mo performance to the point where one could change the parameters of the layers and see an almost instant graphical response. This actually gave rise to the "Inverted SPR" discovery.
Now, since then I was wondering if it wasn't feasible to have the computer scan a huge parameter space on its own and essentially doing a "curve discussion" on its own: A new phenomenon or quality can be described in natural language terms and so can known patterns be described (how are minima, maxima distributed, what are known limits, etc.) as well. The latter would have to be told to the computer and then it would only start spitting out results if it found something remarkable, something outside the known patterns. With today's computing power such a generic software tool would have produced the ISPR instantly! Now I would like to pass on the suggestion: create or find a method to describe and detect patterns in modelled data. Then let a computer scan the areas you find interesting? What do you think? Or is it standard procedure nowadays to do this?
Cheers from Switzerland
Marc
Speed v texture ["depth" can be illusory; detecting interactions and subtle dynamics allows understanding of data flavor but takes time]
Stability v Adaptability [are criteria clear and stable? is it important to detect emergent or unstable characteristics?]
GAs are faster; standard stats are more easily applied [and better understood]; recurrent hierarchical networks are slower and require more intense design but offer granularity and flexibility and can be audited [to a limited extent]
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I am in need of consultation sources on virtual reality technology applications  in the product design development, especially in the preliminary design stage and more precisely in relation to the mechanical parts assembly, ie how to make the parts collide during assembly virtual.
I think what you are lookng for is all SOTA in commercial VR Applications like TechVIz (in combination with you CAD), IC:IDO, Visionary Render or a like.
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I'm performing a validation study and would like to include a study using the deflected NASA Common Research Model that they have used in the 6th Drag Prediction Workshop for the Static Aero-Elastic Effect case.
I've been looking for a while now and I can't seem to find the exact geometry anywhere so was curios if it's been made public or not.
It is happy to hear
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Do any one have any information or the researches about evaluation of the differences between the 3d MSCT/CBCT DICOM-converted-to-STL models (including shrinkage, distortion and Boolean defects) to the various types 3d optical scanned models, such as: dental intra-oral scanned data, extra-oral scanned data (made by desktop scanners, includes: LASER projection type, photogrammetric type and structured light type) (including meshing, registering and patching)?
Appreciated.
Hello,
You might find mesh comparison tools, such as PolyMeCo or Meshlab, useful. You can take a look at:
Cheers!
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I'd like know what kind of figures are used for making modern pixels and what is minimum of their physical sizes now?
An interesting to note is that the shape of the pixels in early Macintosh computers was a square. This made things much simpler for plotting things (a circle is a circle, with x and y axes the same size and the same number of pixels), so software develpopers liked it. No complications of resizing things or sines and cosines...
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Where to find what animation tools and techniques are used by PIXAR studios for making their movies.
They were working with a software they designed thirty years ago called CAPS, Disney used it to color The Beauty and the Beast, and another films. They created RenderMan and you can download a free version.
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what are the latest application area of image processing?
Multiomodal Biometrics, Medical Image Analysis, Digital Forensics
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I really wish to know if there is any good and detailed practical material on L-System for plant growth and development apart from the Algorithmic beauty of plants?
I want to simulate the growth of waterleaf plant (Talinum triangulare) and see the effect of environment and other factors on the plant.
I have tried to use cpfg in L-Studio and I recently saw few articles on Blender, but all these seem not good for me to get the work done.
I believe one of the best developed practical applications of L-systems is L-peach (see below).
We have recently extended L-peach to be used with apples (Fiser, M., B. Shi, J. Ravi, P. Hirst and Benes, B. (2016). IMapple: a source-sink developmental model for Golden Delicious apple trees. in Acta Horticuluturae (InPress)). I will upload the reference when the paper is published.
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I would like to know a good reference (text book and/or library c) of how to adjust/align 2D images.
I am using Dynamic Time Warping to align 2D images along one axis, but I would like to make a multi-dimensional adjustment. I also need the shift matrix associate to this alignment.
You might want to consider the cepstrum approach. Not sure if a ready library implementation exists, but it takes little more than a Fourier transform (and a reverse one), so you should be able to implement it with any math package. Cepstrum was first invented to detect time shift in sonar signals (1D), only later extended to 2D images.
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I have tried in cfd post but not able to do it properly.
0. Make an injection activated.
1. Solution Initialize→Initialize...
2.Calculation Activities→find section "Soluton Animation"→Create/Edit→ Increase the number of "Animation Sequences"→choose "time step" in "When"→Define→Particle tracks→choose what you want→OK→OK
3. Run the calculation and wait.
4.Results→Graphics and Animations→Animations→Solution Animation Playback→choose sequence and set file type to "MPEG".
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Hi,
I have a question and I truly hope you can help me. I am working on a project to develop a new dynamic cervical column. In order to finish the design and show that it works properly, I need a full 3D model of the head and the neck with all the soft tissue and muscles included. I want to remove all the parts beside the bones and skeletal structure, replace the vertebrae with the design and put the removed soft tissue back afterwards to put the design into motion and show that it works. I was thinking about using one of the Zygote solid models but I have no idea if what I want to do is even possible.
any hint is very much appreciated
Many thanks
Mary
I will confirm that Blender  (blender.org) is a good free 3D package could help you. Moreover Makehuman (www.makehuman.org/) can directly import mesh for blender. Makehuman will allow you to create easily a human body exactly parametrize as you wish. You can adjust neck and head parameters just by clicking on some rulers.
You could use some program such MeshMixer, CloudCompare and MeshLab, but they are not that easy to manipulate.
Blender and MakeHuman will allow you to create a clean and easy to handle 3D model. Blender can also import and export in a lot of different format. No if you want good deeper in simulation, you will need something like OpenSim (https://simtk.org/home/opensim). But it is far more advance.
Hope it will help
Best regards
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I am writing a code to create 3D model of object using Epipolar geometry?
I get stuck at finding the Essential matrix from the Fundamental matrix. Since my images are not calibrated, I don't have a calibration matrix.
Please help me if anybody knows a method or code to do the calibration from only images to do a 3D reconstruction.
Yes, it is possible to do that. Instead of using camera calibration data, you can find and match features in your cameras using feature matching methods (the most famous algorithms for this purpose are SIFT and SURF). Then you can form the fundamental matrix in an optimisation process based on the matched features and epipolar geometry.  The optimisation process should minimise the error between the detected point and the epipolar line in the camera image.
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Hi everyone:
I need to do a 3D image reconstruction from the 2D images and it has to be voxel driven.
I think there are couple different ways, however I a not sure if I am right. Please give me some advice and clarification.
1. Using the OpenGL -> I think this one is to build the engine by yourself from the scratch
2. Using the OpenCL and point cloud library(PCL)-> I am not sure if I could render in the voxel driven way
3. Using the commercial available one such as voxelfarm->This requires the paid license.
Any advice will be welcome. Thank you
If you have a collection of 2D images (such as a TIFFstack) or other volumetric file formats such as .mrc, you can view them with most molecular viewers or with a variety of specialized and general 3D data viewers.  For example, UCSF Chimera is a molecular viewer particularly well adapted to viewing volumetric data sets: http://www.cgl.ucsf.edu/chimera/data/tutorials/maps08/volume-basics.html
Whereas programs like Osirix are optimized for viewing 3D medical data such as MRI and CT scans.
NIH puts out a very powerful open-source generalized viewer that handles 3D volumes as well as many other types of data called imageJ: http://imagej.nih.gov/ij/features.html
You can use imageJ to convert 2D stacks to many different 3D formats, etc. and to run powerful surfacing, skeletonization and other types of analysis tools.
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I have a number of group variables that I capture on MCA plots. I also obviously have the coordinates for these plots in the X, Y and Z dimensions. i.e, most people plot the maps as 2 dimensional and then descriptively outline what is going on with the analyses.
You can also do MCA plots in a 3rd dimension (Z dimensions). This would be a 3D plot
Obviously MCA is a visual representation. I was wondering if there are any recognised tests for comparing group differences (e.g, male and female, or 3 way group splits) in the 2D and 3D cases.
I will get through the readings by end of next week. I thought this question may have unearthed a few more spatial mapper types!
I might take you up on the gratis copy of your software. should I send you personal message
regards,
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I am trying to get 3D images of the corroded reinforcement steel bars from 2D images taken at 360 degrees. I need to measure the cross-section at different location using some software which can measure the dimensions from 3D images. I am looking for a 0.01 mm resolution for the measurement and an accuracy for the 3D image that can capture even the small dents in the corroded steel rebar. Could you please suggest any software which can serve this purpose.
VisualSFM may help you reconstruct a 3D model from a number of 2D pictures.
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Hi everybody,
do you know a good entry-point/overview over super resolution algorithms for 3D data (also implementations/libraries are highly welcome)?
I want to produce highly accurate (groundtruth-like) 3D models from multiple partial pointclouds.
Any help appreciated....
Regards,
Bernd
This is what you are looking for. These researchers worked for human bodies, but you might use it for other bodies, I guess.
Y. Cui, W. Chang, T. Nöll, y D. Stricker, «KinectAvatar: Fully Automatic Body Capture Using a Single Kinect», Computer Vision - ACCV 2012 Workshops, vol. 7729, J.-I. Park y J. Kim, Eds. Springer Berlin Heidelberg, 2013.
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Which tool or API is best for creating Physics & Dynamics based  procedural Animation of quadruped characters. Like Unity3D engine, Open Dynamic Engine (ODE), Endorphin, Bullet API, or any other? Please suggest.
houdini
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I'm analysing ER-mitochondria contact sites but I can not find a detailed protocol to obtain 3D reconstructed and surface rendered images with ImageJ.Thank you
I am not an intensive imageJ user, but in Fiji (which is basically an ImageJ), you have the "stacks" submenu in the image tab that allows you to render 3d (3D project).
And in the same fiji, you can also use plugins like "3D viewer" or "volume viewer" to get what you want from a stack.
Have fun
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Please elaborate or refer a source:
How is procedural Generated Animation (PGA) using procedural programming techniques, as used in Games industry, different form Physics or Dynamics based Animation techniques for biped or quadruped locomotion?
A procedural animation is any animation controlled by programmer goal, not real-life one. Examples: procedural generation of plants, particle systems, movement along motion graph, etc. Often such applications are designed just to provide nice look and widely use random elements. But still in the simulation Physics and Dynamics can be used.
If planning of the next group of steps in your case of locomotion depends on game events and interaction with the scene objects, this is not “procedural-based” animation. If the actor or animals walk through the scene in random direction this is a kind of procedure generated animation. In any case algorithm of locomotion simulation still is based on Dynamics or Inverse Kinematics.
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I know it is unusual, but I am wondering if there are any collaborative Virtual reality projects you know of in Edmonton, Canada. My main area of interest is spatial awareness and human material interaction. I appreciate your help.
By mid 2015 there will be a special flights based data gathering for virtual reality examination / simulation around bridge design.
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I am interested in implementing a virtual Morris water maze task for humans in our lab during intracranial recordings. Therefore, I would need a software that allows me to create 3D levels or environments and an output of the virtual position during spatial navigation. Is there any research oriented package for this purpose?
Important note: I am not interested in Oculus Rift kind of virtual reality, but simple 3D First Person Shooter like programs.
Hi,
Can't say much about research on that are but there are some amazing tools for building exploitable 3D environments. Here are the big ones (some free but with conditions):
1) Unity3D http://unity3d.com/
3) Cry-engine http://cryengine.com/
Also you may want to try the free and open-source 3D modelling software and game-engine blender: http://www.blender.org/
Of all of the above I've only used Blender and Unity 3D. Both can take quite some time to learn and develop with (thought Unity is easier from my point of view).
Just a last suggestion. Since maybe you just want a 3D exercise without many visual effects or complexity you could do the easier approach. Check the this link for a kind of FPS in less than 300 lines of code: http://www.playfuljs.com/a-first-person-engine-in-265-lines/
There are many more and you may want to try especially if you decide to use an engine library instead of a a full software solution for development. Examples are:
1) JmonkeyEngine http://jmonkeyengine.org/ (Java)
2) Panda3D https://www.panda3d.org/ (Python)
Some of these engines (such as Unity 3D) come already with an FPS example so you can use it to modify it for what you need. I think it's worth the time exploring a bit the documentation it exists before jumping to a single solution.
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If so then to what extent can this ‘model’ of visual perception be used to direct the development of vision science?
Is this proposition meaningful to a cross-disciplinary section of the research community?
Vision-Space is a new form of illusionary space that's based on perceptual structure and not the fundamentals of optics (or central perspective). It models both the data-strcutures and the dynamic of information exchange taking place within phenomenal field (experiential vision). As such we believe that it starts to model visual awareness. At present the programming architecture for Vision-Space is 'illustrative' in nature. It transforms optical record to accord with our understanding of perceptual structure. Vision it appears, is almost entirely non-photographically rendered. While this software can at present generate Vision-Space moving image media, to move the project forwards we need to create an 'academic' programming architecture advancing a 'generative' programming architecture. This architecture must take account of aspects of neural processing. Such an architecture could obviate the the requirement for optical projection as the basis for image generation and produce stimuli for experimentation to probe perceptual structure in detail.
Hi John,
About twelve years ago I threw in the garbages most of my books on visual perception but I kept six books and the second and third most important were the the two books of Arhneim
-Art and Visual Perception: A Psychology of the Creative Eye
-Visual Thinking
The most important :
A treatise on painting ,Leonardo, da Vinci,
One of my favorite quote from Leonardo is (from memory):
<<The painter has to learn to paint two things: the human body and the human mind. >>
My interpretation is  that the art of painting is basically the art of discovering the way the visual system (the mind) perceive. Learning to paint is thus learning to paint the mind.  It is not an intellectual discovery but painting discovery that can translate in an enhanced capacity to paint sustained by an implicit visual knowledge.  IN the philosophy of science, Michael Polanyi has a theory of discovery based on making explicit implicit personal knowledge.  It has always been my way of learrning although I was not conscious of it.  But the more one become conscious of it and the more bold (some would say crazy) one become.  The more one instead of trying to learn with the intellect just let the body works the way it work and then the intellect cease to be the leader of the process but only what it evolved to be: a medium of communication, not a way to discover.
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A Bézier curve is a parametric curve frequently used in computer graphics, animation, modeling, CAD, CAGD,  and many other related fields.
Bezier curves and surfaces are curves written in Bernstein basis form; so, they are known many years ago. However, these applications are used heavily only in the last 30 years. Why? What are your thoughts and opinions?
Bézier curves are also used in the time domain, particularly in animation and interface design, e.g., a Bézier curve can be used to specify the velocity over time of an object such as an icon moving from A to B, rather than simply moving at a fixed number of pixels per step. When animators or interface designers talk about the "physics" or "feel" of an operation, they may be referring to the particular Bézier curve used to control the velocity over time of the move in question.
The mathematical basis for Bézier curves — the Bernstein polynomial — has been known since 1912, but its applicability to graphics was understood half a century later. Bézier curves were widely publicized in 1962 by the French engineer Pierre Bézier, who used them to design automobile bodies at Renault. The study of these curves was however first developed in 1959 by mathematician Paul de Casteljau using de Casteljau's algorithm, a numerically stable method to evaluate Bézier curves, at Citroën, another French automaker.
Bézier curves are popular because their mathematical descriptions are compact, intuitive, and elegant. They are easy to compute, easy to use in higher dimensions (3D and up), and can be stitched together to represent any shape that you can imagine. These are extensively used in games to describe paths such as racing line, or flight paths. They are also used to describe font characters and automobile body shapes. They are also used for paths used in animation particularly for 3D animation. Most of these developments have grown in the past three decades.
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I am a newbie in using perl and cygwin software. And I need to convert animation that is already done by using 3ds Max into OpenGL.
But I have no idea on how to start the script. Anyone?
Perl is not primarily oriented at graphical processing.
But I would suggest you search for Perl module(s) which interface with OpenGL.
I see there is something called "POGL" (see http://en.wikipedia.org/wiki/Perl_OpenGL); I've never used it but maybe this is what you need.
You'll of course also need (first) a sufficient basics in Perl. (There exist 3-day intensive courses which teach you those basics, and of course there are good books & good online tutorials as well.)
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What is the accuracy of such reconstruction methods with regards to the vibrations of the flying drones, quality of camera and resolution? Is it possible to improve the results by organizing multiple flights and overlaying/accumulating the data in the point cloud? Is there any free software available?
Hi Reiner,
I would say the best method would be Structure-from-Motion (SFM) based methods. Ofcourse, the challenges with flying platforms would be vibrations and video stability but techniques exist to deal with these to great extent. Visual SFM by default would generate relatively sparse point clouds but with surface fitting and strong priors based reconstruction you can improve the results greatly, atleast in my experience. I would recommend VisualSFM (http://ccwu.me/vsfm/) to be a good starting point to experiment with.
Tauseef
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Complex number image in MATLAB.
How can I make an RGB image a plural version in MATLAB? And what do complex angle and mold represent?
Why sometimes we convert from RGB version to plural version?
Thanks :P
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Looking for an up-to-date text. GPU Gems comes to mind.
Thanks!
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The method should be aware geometric properties of the mesh (for example: edges, normals, curvature,..) . It means that the method will makes dense sampling or sparse sampling depending on the sampling region. I appreciate for any suggestions.
It depends on the software you use. We normally decimate 3D models from laser scanner with Rapidform, but you can find the "decimate" option in most of 3D software, modelling or reverse engineering (Blender, MeshLab -open source- or Rhino, Rapidform and many others -commercial-). Most of them use specific algorithms to preserve the shape (so you will have stronger decimation on flat surfaces).
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3D image processing
If 3D reconstruction is what you are aiming at then I would say you first need to calculate the depth. it is highly difficult to get accurate depth information from a single 2D image. One of d most popular approaches to this problem is stereo triangulation which requires you to have atleast of two images( corresponding to left eye view and right eye view). If you do have more than one 2D images, you should be able to get depth co-ordinates using stereo triangulation methods.
Here is an interesting webpage which talks about acquiring depth from single image.
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This is a computer graphics question. We need the mesh to dilate its concave parts, while keeping its convex parts unchanged. The deformed mesh will enclose the original mesh, just like a convex hull.
THANKS!
I was thinking about something like :
FOR all non-convex-hull-patches DO
{
Label the vertices that are connected to a convex hull vertex with ONE
Label the non-labeled vertices that are connected to ONE with TWO
Label the non-labeled vertices that are connected to TWO with THREE
etc...
Map the labeled vertices to the convex hull using the label as a distance criterion to the rim (easier said than done!)
}
Note that the algorithm will fail with tori.
In my first answer, I said that "concave parts that have convex islands in them that ARE part of the convex hull" complicated the matter. In fact it does NOT: you can treat them as if they are also part of a non-convex-hull patch, and in the mapping phase, you know exactly where to put them because they keep their original position.
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I'm measuring angular movement of each finger joint in the human hand. I'm using three reflective markers across each finger joint to determine each joint angle. One marker is placed on top of the relevant joint, with one on either side of it. I'm currently measuring movement using the dot product of recorded data. I noticed however that there is an option when exporting the movement csv file to add kinematic values, but this does not produce angular measurement. Any suggestions?
I use a similar marker placement to measure finger angular motion in the hand, but use the motion analysis system and the cortex software. I don't have much experience with Nexus, but I know that with cortex I convert the mocap file to a c3D and export. I then calculate the angles of the markers using visual 3D software, using commands from the pipeline. You can also calculate in labview. You can probably customize a pipeline in vicon to produce the angular measurements. Cheryl Metcalf developed a marker placement system called HAWK that may be helpful to you as well. http://www.cherylmetcalf.co.uk/hawk.php
Here is the reference to her publication as well
Metcalf, C. D., Notley, S. V., Chappell, P. H., Burridge, J. H. & Yule, V. T., 2008. Validation and Application of a Computational Model for Wrist and Hand Movements using Surface Markers. IEEE Transactions on Biomedical Engineering. 55(3), 1199-1210.
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We want to restore an image using additional vector constraints.
The surface is flat, so looks like could work, I'll try it, thanks Waqar
Emilio
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Rink-side advertising of major sports events is often not really there at the actual event, but is regionalized and added in the live TV-mix of the event. This is standard practice, but does anyone know if the same is done with the advertising on the players´ suits? I.e. whether the logo on a star football player's chest is added in the TV-mix, or is that just advertising sci-fi?
Thanx for the tip! - seems like an interesting company to, I´ll keep an eye on you. I am in the process of writing a book chapter on advertising in converging media. Do you know of any instance when a professional sports team has applied this in a full scale public situation like a televised match? :-)
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I have started a new project in which I want to include the option of searching some text strings within SVG formatted image in my web page. According to my knowledge this is not possible in any raster image format. That is why I am using xml based SVG image format. This kind of feature is already available in inkscape (a software to draw svg images) and www. wikipathways.com, where an user can search a text string inside the image.
Can anybody tell me how I can include this feature in my webpage? And also I want highlight that particular matched string.