image-processing

BufferedImage & ColorModel in Java

I am using a image processing library in java to manipulate images.The first step I do is I read an image and create a java.awt.Image.BufferedImage object. I do it in this way, BufferedImage sourceImage = ImageIO.read( new File( filePath ) ); The above code creates a BufferedImage ojbect with a DirectColorModel: rmask=ff0000 gmask=ff0...

character matching in grayscale image

I made patterns: images with the "A" letter of different sizes (from 12 to 72: 12, 14, .., 72) And I tested the method of pattern matching and it gave a good results. One way to select text regions from image is to run that algorithm for all small and big letters and digits of different sizes. And fonts! I don't like it. Instead of it I ...

How to use Haar wavelet to detect LINES on an image?

So I have Image like this I want to get something like this (I hevent drawn all lines I want but I hope you can get my idea) I want to use SURF ( (Speeded Up Robust Features) is a robust image descriptor, first presented by Herbert Bay et al. in 2006 ) or something that is based on sums of 2D Haar wavelet responses and makes an e...

Is there any algorithm for finding LINES by PIXEL COLORS on picture?

So I have Image like this I want to get something like this (I hevent drawn all lines I want but I hope you can get my idea) I need algorithm for finding all straight lines on it by just reading colors of pixels. No hard math, no Haar, no Hough. Some algorithm which would be based on points colors. I want to give to algorithm para...

computing matting Laplacian matrix of an Image

hi everyone, i need to compute Laplacian Matrix-L for an image(nXn) in opencv...computing goes as follows.......... δij − 1/|wk|{[1+1/(ε/|wk|+σ2)][(Ii-µk)*(Ij −µk)]}.... for all(i,j)∈wk,summing over k yields (i,j)th element of L. where Here δij is the Kronecker delta,µk and σ2k are the mean & variance of inten...

How do I automate the padding for arbitary images using MATLAB?

This is a further question based on this answer: http://stackoverflow.com/questions/2589851/how-can-i-implement-this-visual-effect-in-matlab/2589957#2589957 The general solution should work for all background colors and length/width ratios. ...

asp.net image aspect ratio help

Hey all, i am in need of some help with keeping an image aspect ratio in check. This is the aspx code that i have to resize and upload an image the user selects. <%@ Page Trace="False" Language="vb" aspcompat="false" debug="true" validateRequest="false"%> <%@ Import Namespace=System.Drawing %> <%@ Import Namespace=System.Drawing.Ima...

Finding edge and corner values of an image in matlab

Hi, this problem links to two other questions i've asked on here. I am tracing the outline of an image and plotting this to a dxf file. I would like to use the bwboundaries function to find the coordinates of the edges of the image, find the corner coordinates using the cornermetric function and then remove any edge coordinates that are...

mean and variance of image in single pass

hi everyone,am trying to calculate mean and variance using 3X3 window over image(hXw) in opencv...here is my code...is there any accuracy issues with this??or is there any other efficient method to do it in one pass.? int pi,a,b; for(i=1;i<h-1;i++) { for(j=1;j<w-1;j++) { int sq=0,sum=0; double mean=0; double...

How to retrieve the background color of an arbitary image using MATLAB?

This is yet another questions springed from this one, How do I programatically get the background color of an image? Example: For the above image,the background color is white. ...

convert RGB values to equivalent HSV values using python

Hi, I want to convert RGB values to HSV using python. I got some code samples, which gave the result with the S and V values greater than 100. (example : http://code.activestate.com/recipes/576554-covert-color-space-from-hsv-to-rgb-and-rgb-to-hsv/ ) . anybody got a better code which convert RGB to HSV and vice versa thanks ...

Create thumbnail images for jpegs with python

As the title says i am looking for a way convert a huge number of images into thumbnails of different sizes , How do i go about doing this in python ...

creating HSV histogram using RGB image

Is there a way in Java or OpenCv ; preferably Java, that i can have an HSV histogram give RGB image. I tried exploring JAI but it creates histogram for RGB image. Thanks Harshit ...

Rendering text in an image in Java

Are there any nice libraries to render text in an image for Java? Java has a 2d text library, http://java.sun.com/docs/books/tutorial/2d/text/index.html but not sure if theres a better library to use. ...

Determine coordinates of rotated rectangle

I'm creating an utility application that should detect and report the coordinates of the corners of a transparent rectangle (alpha=0) within an image. So far, I've set up a system with Javascript + Canvas that displays the image and starts a floodfill-like operation when I click inside the transparent rectangle in the image. It correct...

How can I access the JPEG image pixels as a 3D array like we do in MATLAB?

I want to process an image in C++. How can I access the 3D array representing the JPEG image as is done in MATLAB? ...

Image classification: recognizing various features of many buildings from images

so, let's say i have the long/lat or address of many buildings can get satellite images, "street view", and perhaps 3d/perspective views of buildings. want to find: height, number of floors, floor area (max building footprint) of the building. about 200k buildings. Is there a library for recognizing buildings from satellite shots o...

.NET photo processing component

Hi folks! I'm looking for a .NET image processing component or an open source alternative to automate the following tasks: Photo capture (webcams and photo cameras) Photo printing (grid/strip modes) Applying photo effects Saving photos AtalaSoft DotImage is quite expensive, any other suggestions are welcome. Thanks J ...

On-the-fly lossless image compression

I have an embedded application where an image scanner sends out a stream of 16-bit pixels that are later assembled to a grayscale image. As I need to both save this data locally and forward it to a network interface, I'd like to compress the data stream to reduce the required storage space and network bandwidth. Is there a simple algori...

Image 8-connectivity without excessive branching?

I'm writing a low level image processing algorithm which needs to do alot of 8-connectivity checks for pixels. For every pixel I often need to check the pixels above it, below it and on its sides and diagonals. On the edges of the image there are special cases where there are only 5 or 3 neighbors instead of 8 neighbors for a pixels. Th...