distortion

I need to make an application in iphone which needs to calculate noise, geometric deformation other distortions in an image. How to do this? I have done some image processing stuff with opencv + iphone. But I dont know how to calculate these parameters. 1) How to calculate noise in an image? 2) What is geometric deformation and how to calculate geometric deformation of an image? 3) Is geometric deformation and distortion are same parameters in terms of image filter? or any other distortions available to calculate an image is good quality or not? Input: My image is a face image in live video

I want to know the best way to fit a sine-wave with a distorted time base, in Matlab. The distortion in time is given by a n-th order polynomial (n~10), of the form t_distort = P(t) . For example, consider the distortion t_distort = 8 + 12t + 6t^2 + t^3 (which is just the power series expansion of (t-2)^3 ). This will distort a sine-wave as follows: I want to be able to find the distortion given this distorted sine-wave. (i.e. I want to find the function t = G(t_distort) , but t_distort = P(t) is unknown.) Here's an analytical driven route that takes asin of the signal with proper unwrapping

I think I should be using cv::remap to remove the distortion but can't figure out what the the maps const Mat& map1, const Mat& map2 to should be to achieve this. Should I be using the cv::initUndistortRectifyMap to find out the values? If so, I'd really appreciate an example. I do not have the intrinsic camera parameters or don't know how to calculate them. Thanks. karlphillip If you are looking to remove the distortion caused by the camera lens you should take a look at this answer I wrote some time ago, which has intructions and references on how to do proper camera calibration. I also

So I am very new to OpenCV (2.1), so please keep that in mind. So I managed to calibrate my cheap web camera that I am using (with a wide angle attachment), using the checkerboard calibration method to produce the intrinsic and distortion coefficients. I then have no trouble feeding these values back in and producing image maps, which I then apply to a video feed to correct the incoming images. I run into an issue however. I know when it is warping/correcting the image, it creates several skewed sections, and then formats the image to crop out any black areas. My question then is can I view

I'm looking for the algorithm (bitmap pixel manipulation) to simulate the fisheye lens (Barrel Distortion) from normal pictures. So far I've found implementation involving external libraries like OpenCV, OpenGL or jhlabs. Since I'm taking a class in Digital Image Processing and I'm making a course assessment project, I'm not sure whether using any external lib will earn me a good grade. So would anyone give me the reference to such algorithm? Ps. I'm asked to implement it in Java, but example from any language would do. mpenkov It's good that you've been able to find examples that do what you

I have some images that takes using mobile phone. Is there any JavaScript library which can straighten the photo of a paper and flatten it? For example I want to create a rectangular image without any distortion from this image. In the other words I want to know how to fix perspective distortion and rotation with JavaScript? For example I found below sample image from this article: How to fix this type of image with javascript? Looks like https://www.npmjs.com/package/perspective-transform is what you are looking for. Create functions to map points from one arbitrary quadrilateral to another