I have an implicit scalar field defined in 2D, for every point in 2D I can make it compute an exact scalar value but its a somewhat complex computation. I would like to draw an iso-line of that surface, say the line of the '0' value. The function itself is continuous but the '0' iso-line can have multiple continuous instances and it is n...
Hi i have been working on this for a while and yet to have no good solution. I am reading a video frame by frame and am using background subtraction to ' identify the region where is there movement and use cvFindContours() to get the rectangle boundary of the moving objects. Assuming the program is kept simple there can be only 2 human...
Hi, How would I go about constructing the contour of 2d figure which is formed of only triangles and it can have holes and the external contour can be concave/convex and the holes can also be concave/convex. From what I'm reading over here it seems that It's exactly the inverse of the triangulation problem. Do you know any articles tre...
hi, I am currently working on a data visualization project.My aim is to produce contour lines ,in other words iso-lines, from gridded data.Data can be temperature, weather data or any kind of other environmental parameters but only condition is it must be regularly spaced. I searched in internet , however i could not find a good algorith...
I am looking for a function or example to produce a list of lines representing contours at a specific height within a heightmap. Eg, Lines[] = GetContours(Heights[512,512], HeightValue) Where Heights is a 512x512 array of floating point values, HeightValue is the height at which the contour should be drawn. Heights may contain multip...
Hi, I have an image which is a binary mask, I want to characterize the contours of the black zones in the mask, I have found several funtionalities to detect the borders between both zones but only as a new image but what I want is the description of this border, not a new image. Is there any functionality in java advance imaging or in ...
I'm working on a Image-processing chain that seperates a single object by color and contour and then calculates the y-position of this object. How do I calculate the center of a contour or area with opencv? Opencv links: http://opencv.willowgarage.com/wiki/ http://en.wikipedia.org/wiki/OpenCV ...
I'm using the Python OpenCV bindings to find the contours in an Image. I'm know looking for the possibility to sort this sequence. It seems the usual python ways for list sorting don't apply here because of the linked list structure generated from OpenCV. Do you know a good way to sort the Contours by Size (Area/BoundingRectangle) i...
Hi, I want to calculate a convex hull around a shape in a binary NxM matrix. The convex hull algorithm expects a list of coordinates, so I take numpy.argwhere(im) to have all shape point coordinates. However, most of those points are not contributing to the convex hull (they lie on the inside of the shape). Because convex hull computati...
How do I generate a contour graph like this: It's easy enough if the points are on a regular grid, but what if they aren't, like in my example? Is there a fairly simple algorithm to determine the color for each pixel? ...
Hi, I have a set of points represented as a 2 row by n column matrix. These points make up a connected boundary or edge. I require a function that traces this contour from a start point P1 and stop at an end point P2. It also needs to be able trace the contour in a clockwise or anti-clockwise direction. I was wondering if this can be ac...
FT can only be used to select feature for a single closed curve, how can I use it for several separate disconnected closed curves as a whole? A solution in MATLAB will be the best though not mandatory. ...
I would like to control the location of matplotlib clabels on a contour plot, but without utilizing the manual=True flag in clabel. For example, I would like to specify an x-coordinate, and have labels created at the points that pass through this line. I see that you can get the location of the individual labels using get_position(), but...
At the bottom of this image, you'll see a nice colorbar that matches the colors of the graph correctly: http://stribog.cc.umanitoba.ca/ceos/20100517_00z_prod/ I couldn't find anything that created a color bar with exactly the colors I wanted, it always seemed to involve a spectrum that included colors I didn't use. I have a vector of ...
I am using a map_set call to draw a map, and then using contour to plot some data on top of it. I want to add a legend to this plot to make it useful, but it would have to be below the entire plot, and everything I've tried creates an overlapping legend over top of my image. ...
I am looking for an Open Source .NET Library (or wrapper to a library) that will create contour plots from a set of values along a grid/mesh. ZedGraph is the closest thing I could find (http://zedgraph.org/). It would also be great if it could export to EPS. ...
I have a gray scale image of 64x64. I found the dots of the contour by a simple algorithm: find brightest spot (Example: 100) divide by 2 (100/2 = 50) define a band around the result (50-5=45 to 50+5=55) mark all dots that have value in the band (between 45 to 55) The question now is, how do I decide of the order of connecting the d...
I have a custom function which returns either 0 or 1 depending on two given inputs. function val = myFunction(val1,val2) % logic to determine if val=1 or val=0 end How can I create a contour plot of the function over the x,y coordinates generated by the following meshgrid? meshgrid(0:.5:3,0:.5:3); This plot will just simply di...
I am trying to calculate 3D shapes out of a 3 dimensional matrix of samples. My idea is that I would have a 3 dimensional matrix of data points, with each corresponding location in (X, Y, Z) space, and from this I would determine a set of 3 dimensional shapes in the (X, Y, Z) space that each outline data points of similar values. Somethi...