Images Definition and 388 Threads

An image (from Latin: imago) is an artifact that depicts visual perception, such as a photograph or other two-dimensional picture, that resembles a subject—usually a physical object—and thus provides a depiction of it. In the context of signal processing, an image is a distributed amplitude of color(s). A pictorial script is a writing system that employs images as symbols for various semantic entities, rather than the abstract signs used by alphabets.

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  1. J

    MHB Physics: Images through Thin Lenses

    A thin lenses with given p = 75cm, n = 1.55, r1 = 30cm, and r2 = -42cm. Find the a.) i b.) m c.) Is the image real or virtual d.) Is the image inverted or noninverted e.) Is the image on the same or opposite side as the object Using 1/p + 1/i = 1/f and also 1/f = (n-1)*(1/r1 - 1/r2) I...
  2. kos

    Telescope Images: Light Deflection & Alien Observation

    http://www.askamathematician.com/2013/04/q-what-kind-of-telescope-would-be-needed-to-see-a-person-on-a-planet-in-a-different-solar-system My speculative question on the subject is in the sphere of Einstein General relativity applying to the problem. So we all now know that when light passes...
  3. Ryan_m_b

    Asking machines to identify images

    I can't get over how cool/creepy this is. Researchers took image recognition neural networks and asked them to look for certain images in random noise and once identified modify the image to highlight the pattern. That new image is fed back into the machine and it's asked to do the same again...
  4. R

    Algorithm to compute Basis images of an image

    I know from the Fourier Analysis that any signal can be represented as summation of elementary signals i.e. basis functions .Likewise,any image can be represented as summation of Basis images. Is there any available code, or even an algorithm, that would allow me to compute Basis images of an...
  5. I

    Color images of red/green lasers

    Hi all, I'm new to the forums. I recently tried to take an image of two laser dots on a white wall, using my laptop's USB camera. I saved them to PNGs. I have a number of questions... 1. There was an artifact with the green laser, where a smaller second dot appeared for some reason. What...
  6. E

    Exploring Real & Inverted Images with Bi-Convex Lenses

    Homework Statement An object is placed between the optical centre and the focus point of a bi-convex lens. The image obtained is always inverted and real. Is this statement true? Justify your answer using the thin lens equation. Homework Equations The Attempt at a Solution
  7. M

    Green's function + method of images

    Hello, I'm trying to understand the application of Green's function to find the potential better. I apologize in advance if I start mixing things up a little. From what I understood and seen, we use this method (Green and method of images) in known symmetries (cylindrical/spherical/planar) and...
  8. Q

    Engineering From which books of Mechanic Materials are these images?

  9. PWiz

    Difference between images produced by gravitational lensing

    Around massive bodies, light bends so that we can see multiple images of the same object, such as multiple images of the same galaxy behind the massive body. I know this seems kind of a dim question, but how can we know that the similar images we pick up are light rays from the same object that...
  10. GiantSheeps

    Stargazing Help with telescope/observatory data and images

    I was wondering if anyone would help me get my hands on some telescope data and images of exoplanets. I know they must exist somewhere in databases on the internet, but I haven't been able to find them myself. It would be great if one of you could show me where I could get them or even if you...
  11. Helios

    Why does Google Images keep jumping to the top of the page?

    Dear Computer People, Perhaps most everyone is familiar with google images. There are thumbnail pictures, you click on them and they enlarge. Now when I do this, the whole page jumps to the top every time. Only this last week did this begin. I tried to rejuvenate using the reset to previous...
  12. G

    How do cameras focus on reflected images?

    I can remember from my distant school physics days that the image in a mirror lies beyond the mirror. But how does a modern camera sensor "know" this. If I face a mirror with my canon camera which has a cmos sensor and usm lens, it autofocuses correctly on the part of the reflection I select...
  13. F

    Multiple images in a thick mirror

    I understand that 4% of the light is reflected back from the glass surface in a thick glass mirror. But why 4%? Why not 5% or 10%? Will this percentage change if the glass has a lower refractive index?
  14. V

    Can we decrese the timegap of space telsecope images?

    Hi Recently I have watched a video from The Hubble Telescope on You Tube . He says,light travels with the speed of light through the space for billions of light years to reach us from other planet . The images what we are seeing from the Hubble telescope are the past images of that particular...
  15. B0b-A

    What's the scale on Mars rover "Microscopic Imager" images ?

    What's the scale on Mars rover Opportunity's "Microscopic Imager" images ? I'm trying to work out if the Martian "fossil" shown could be the impression of a cross-head-screw ... http://mars.jpl.nasa.gov/mer/gallery/all/1/m/3720/1M458433044EFFCEQKP2955M2M1.HTML
  16. rayne1

    MHB Determine the images of the functions f: R -> R....?

    Determine the images of functions f: R -> R defined as follows: a) f(x) = x^2/(1+x^2) b) f(x) = x/(1+|x|) I have no idea if I am doing it right but this is what I did for a): The two sets: f: A -> B The image of f is the set b ∈ B such that f(x) = b has a solution. Since f(x) = x^2/(1+x^2) and...
  17. Telemachus

    Electric Potential in Region z>0 Using Method of Images

    Hi there. The example to obtain the electric potential in the region z>0 by the method of images for a infinite grounded conducting plane, with a point charge q located at a distance d is a typical example of the application of the method of images. If we consider that the plane is located in...
  18. ajayguhan

    Solving a Math Homework Problem: Images Attached

    Homework Statement I have attached the question in image format. Homework Equations The Attempt at a Solution I attached my attempt at solution as images. Kindly have look at them.
  19. R

    Understanding Sets & Images: A Beginner's Guide to Set Theory

    Could someone please explain how the image of a set A' ⊆ A is the set: f(A') = {b | b = f(a) for some a ∈ A'}. And how can the complement of A be a subset of A? Forgive my ignorance here, I'm a beginning student of set theory. Edit: Maybe I should rephrase my question: Could you explain what...
  20. Monsterboy

    How to find the date of creation of uploaded images?

    If i had uploaded an image in a website (and if i don't have the image right now in my PC), is there a way to find the date of creation of the uploaded image?
  21. E

    How do I enhance low quality JPEG images?

    Is there any way to enhance low quality and low resolution JPEG images? Is there a program I can use or something? I have dozens of grainy and poor quality JPEGs that I would like to sharpen up, but I do not own photoshop.
  22. C

    Optics: Spherical Interface -- Real and Virtual Images

    Homework Statement If you have a spherical interface between two different "media" (like air and water), and an object is placed in the one with the lower index of refraction, with the interface being convex toward the object, how can you tell if the image will be real or virtual? Here's a...
  23. J

    Determining Missing Images in an Even Permutation

    Homework Statement Hi, I have been MIA lately due to work, but I am back with questions, and eager to learn! I am self studying, and so I have inconsistencies in my learning which I hope to iron out. Suppose you are told that the permutation ( 1 2 3 4 5 6 7 8 9 3 1 2 X Y 7 8 9 6) In S9...
  24. S

    Creating 3d coordinates from stereoscopic images

    Hi, I'm working on a project that would take a 3d image using stereocopic camera and would record the depth and the 2d (x1,y1) , (x2,y2) coordinates of a single point in the image. The depth is found using the focal point, disparity, and the distance between the difference the camera sees on...
  25. R

    How can we represent an image using basis images?

    I have read that using Fourier transformation we can decompose any arbitrary image into othogonal basis images and reconstruct it back. But i don't understand terms like "othogonal " and "basis image". So can anybody shower their ideas on the above terms with example ??
  26. Superposed_Cat

    C# C# breaking monochrome image down into new images.

    Hi all, c# coder here, i am seeking ways to segment images into separate bitmaps based on colour values. I have an image, and i have already applied edge detection and changed the threshold to 230 to give me black and white "blobs". Now the issue is finding these blobs, and copying them into...
  27. S

    MHB Quotient rings and homorphic images

    am given that ϕ is a function from F(R) tp RxR defined by ϕ(f)=(f(0),f(1)) i proved that ϕ is a homomorphism from F(R) onto RxR. i showed that 1) ϕ(f) +ϕ(g)=ϕ(f+g) [for all f,g in F(R)] 2)ϕ(f)*ϕ(g)= ϕ(f*g) how do i show that ϕ is onto and define the kernal??(Wasntme)
  28. Spinnor

    Nice general collection of high resolution astro images.

    Nice general collection of high resolution astro images. http://www.holtz.org/Library/Images/Slideshows/Gallery/Cosmic/
  29. F

    How are Virtual Images Formed and Why Do Definitions Matter?

    I understand that virtual images are formed when two rays APPEAR to meet and do not actually meet (lenses and mirrors) and that is why we extend the reflected (or refracted) rays behind. But that is as far as the drawing goes. What is actually happening to the rays to form a virtual image? (They...
  30. Math Amateur

    Question regarding scanned images in texts

    Some time ago I posted the following: "Can someone give me an idea of how to include (the scan of) a small diagram - say 1/4 to 1/3 of the size of an A4 page (thus not the whole page) - into a post - in such a way as the diagram is visible to the reader - that is he/she does not have to open...
  31. miraiw

    Could fluorescence quenching be used for making 3D images?

    Looking at the image from this wikipedia article, it looks like there's a selective fluorescing of the quinine dependent on the presence of chrolide ions in the solution. If the concentration of chloride ions in a solution could be controlled into a particular shape, shining a violet laser on...
  32. Rectifier

    LaTeX Troubleshooting Image Display in LaTeX

    Hey! I can't get my images to appear in ##LaTeX## :( Could you please help me out? I have read that you can use \includegraphics but when I add it in my code nothing happens. \documentclass[a4paper,11pt]{article} \usepackage[swedish]{babel} \usepackage{graphicx} \begin{document}...
  33. M

    Why does a positive lens focus two images at different lengths?

    Missed this part of the lab and I need to complete my lab write up. We have a light source at one end of a track, and at the other end a screen. there is a positive lens in between them. When we set the screen at a distance away from the light source, let's say one meter, and slide the lens...
  34. A

    When we look at cosmic web images, what do we see?

    Looking at images of the cosmic web, I would have expected the view to change the older the galaxies are. I understand homogeneous nature of the universe however, I thought it would have been as viewed in the same time reference. Basically the universe is homogeneous with respect to time not...
  35. A

    Tracking flight 370 : Can we use satellite images to find it?

    I think we can find flight 370 if we have satellite images of the flight. The question is, do we have any such images of the actual flight as it was in progress? It was a clear night. Even if the images are low resolution, as long as the color of the plane is distinguishable from its...
  36. Y

    MHB Solve Constant Alpha's in Images: Help to Understand and Get Unstuck

    The book answer is 1, 3 and -2. I can't figure how they got it? Please help to understand and help me to get through where i got stuck. Please look at images from bottom page to top page(where you see crossing on a page)
  37. K

    Physics 3: Images, Interference and Difraction

    So three problems I am stuck on. 1.) You have a converging lens with n=1.5,for a symmetric lens so the two lens have same magnitude, what should the radius of curvature be so the focal length is 10cm. I know 1/f = (n-1)[1/r1-1/r2] so that is 1/0.10m =(1.5-1)[1/r1-1/r2] where I am lost is in the...
  38. fluidistic

    LaTeX Latex help needed, about text between 2 images

    Latex "help" needed, about text between 2 images I'm having troubles to place a text between 2 images. The code looks like this: \begin{figure}[ht] \begin{minipage}[b]{0.45\linewidth} \centering \includegraphics[width=\textwidth]{vvalue} \caption{value1} \label{test1} \end{minipage}...
  39. Hyo X

    Interpreting 2-D FFTs of images

    I have electron microscope images of structures of varying periodicity, ranging from highly crystalline to highly amorphous. It is relatively straightforward to take FFTs of these images, but what i want to do is extract a quantitative value to characterize crystallinity and compare it between...
  40. V

    Images produced by a simple two lens microscope?

    Homework Statement The image formed by a simple two lens microscope is (a) real and inverted. (b) real and upright. (c) virtual and upright. (d) virtual and inverted. (e) none of these. Homework Equations N/A The Attempt at a Solution I was confused on how to understand how...
  41. D

    What is a Pigment network in Dermoscopy Images?

    hi all, So here I am reading a paper "A System for the Detection of Pigment Network in Dermoscopy Images". I want to ask what actually is a pigment network? thanks
  42. R

    How Many Images Does a Zone Plate Produce with an Object in Front?

    How many images does a zone plate produces when an object is placed infront of zone plate?
  43. E

    Recommended software for converting 2D images to 3D CAD model.

    Hello, Does anybody know/had experience with software that can turn 2D images to 3D models in CAD program, preferably in an offline environment (not on cloud)? The resulting model has to be accurate enough for aerospace engineering purposes. from looking online, I really didn't find...
  44. B

    Calculating Charge & Electric Energy Above a Plane

    Hello, I am stuck with this one. Your help/comments would be most appreciated. A charge "+Q" lies at a distance "d" above an infinitely large conducting plane. Applying the method of images, i found the right result that the total charge of the infinite plane is "-Q" and that the stored...
  45. M

    Sets and equivalence between images of sets

    Homework Statement Let f be a function from E to F . Prove that f is an injective function if and only if for all A and B subsets of P(E)^2. f(A\cap B)=f(A)\cap f(B) The Attempt at a Solution Well since we have "if and only if" that means we have an equivalences so for. \Rightarrow If f...
  46. A

    Possible Images of a Linear Map T:R4->R4

    Homework Statement Show that a linear map T:R4->R4 has one of the following as its image: just the origin 0, a line through 0, a plane through 0, a copy of R3 through 0, or all of R4. Homework Equations N/a The Attempt at a Solution I'm not sure I'm even understanding the...
  47. GreenAce92

    Is it possible to use air as a medium to display images?

    Yes holographs but not really So... I guess what I'm trying to get around is energy levels I will admit that my understanding is vague I believe I understand that certain gases are easier to excite (to give off light when going back down) like xenon but what about the general...
  48. MarkFL

    MHB Math related images for movie and book titles

    I thought it might be fun if we created our own math related images that can be translated into a movie title, or perhaps even book and song titles. The first person who guesses the title correctly then gets to create their own image. So, I will start with a movie title:
  49. V

    Do images move faster than objects?

    Homework Statement A cat sees its image in a plane mirror. The cat is 1 m from the mirror. A) Where is the image? B) The cat lunges at the mirror at 2 m/s. How fast does the cat approach its image? The Attempt at a Solution I understand that for a, the image would also be 1 m away...
  50. H

    Can Mathematica Produce High-Quality Plots of Hermite Gaussian Polynomials?

    Homework Statement Hello everyone, I was trying to plot (density plot and 3d plot) Hermite Gaussian polynomials on Mathematica hoping the plot will be good enough to show patterns such as this link ...
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