How to identify/check blur image?
Hi How can we identify that a given image is blur or how much percent is it blur in C#? Is there any API available for that? Or any algorithm that can be helpful in that? Thanks! ...
image-processing
How Is The Structure Of a Image
Hello, I'm thinking to build a library to manipulate images(my own image type that I will develop), but first I need to understand the structure of a image How it is mounted? About the layer technology... Where I can find some good resources to understand these things? Thanks. ...
XSLT: Convert base64 data into image files
I have seen several questions on how to encode an image file in base64, but how about the other way around - how do I reconstitute a picture from a base64 string stored in an XML file? <resource> <data encoding="base64"> R0lGODlhEAAQAPMAMcDAwP/crv/erbigfVdLOyslHQAAAAECAwECAwECAwECAwECAwECAwECAwEC AwECAyH/C01TT0ZGSUNFOS4wGAAAAAxtc09QTVNP...
Using existing tools, how can I extract into separate images the Luma, Cb, Cr channels of a JPEG image?
I am seeking a method to extract into separate images the Luma (Y), Cb (blue component), Cr (red component), channels of the JPEG images: Seattle Police Department image #1 Seattle Police Department image #2 Seattle Police Department image #3 I would like results equivalent to this example from Wikipedia. The output must be calculat...
PVRTC compression increasing the file sizes of PNG
For iPhone game development, I switched from PNG format to PVRTC format for the sake of performance. But PVRTC compression is creating files that are much bigger than the PNG files.. So a PNG of 140 KB (1024x1024) gets bloated to 512 KB or more in the PVRTC format.. I read somewhere that a PNG file of 50KB got compressed to some 10KB and...
Transforming captured co-ordinates into screen co-ordinates
Hi everyone. I think this is probably a simple maths question but I have no idea what's going on right now. I'm capturing the positions of "markers" on a webcam and I have a list of markers and their co-ordinates. Four of the markers are the outer corners of a work surface, and the fifth (green) marker is a widget. Like this: Here's ...
CONTEST: optimize size of grayscale scanned documents!
I put this as a contest, but it's still a question! Here's the original image: http://dl.dropbox.com/u/1663633/original_scan.jpg Original size is about 1 megabyte. How would you reduce the size so that the final print on a A4 paper (about letter size I think..) still looks good? Rules: The process MUST be automatic (to be applied to...
Basics of normalized cross correlation
I am trying to use normxcorr2 (normalized cross-correlation) from MATLAB for calculating velocity of moving shapes in a developing embryo. I have 3 questions: 1) My image size is 260x360 pixels. I give a template size of 10x10 pixels and I ask the command to search for this template in the subsequent frame in a search window of 50x50 pi...
Make panoramic images from few images taken from one position
Does anybody know some open-source framework, code examples etc for the follwoing problem? I have a few images of the same object. Need to find a way how to stitch them into one panoramic image. ...
Detect marker in 2D image
I am hoping to obtain some some help with 2D object detection. I'll give a brief overview of the context in which this will be implemented. There will be an image taken of the ceiling. The ceiling will have markers placed on it so the orientation of the camera can be determined. The pictures will always be taken facing straight up. My ...
Detecting forged images with C#?
One of my friends came up with an interesting problem - Assume that we have a set of images in the system. Now, some one might submit a new image by slightly modifying any of the images already submitted, and in that case, the system should report that the submitted image is a forged image. I can think about two solutions. Solution 1 ...
Patent on server side image generation
I was just browsing on server side image generation and stumbled on following link: http://www.encke.net/Article13.html Does any of you know if this holds good any more or not? Did anybody challenged this patent? What does this patent mean? Do I need to respect this patent in UK and other countries too? ...
Ruby/Rails image processing libraries
Good friends of stackoverflow, I am here today for guidance regarding image processing/manipulation using Ruby in a Rails environment. I'm creating on-the-fly dynamic banner ads that will feature mostly (if not completely) text. It's fairly simple with just a line or two, but I'd like the option to adjust font, text color, text size, etc...
Detecting image equality at different resolutions
I'm trying to build a script to go through my original, high-res photos and replace the old, low-res ones I uploaded to Flickr before I had a pro account. For many of them I can just use Exif info such as date taken to determine a match. But some are really old, and either the original file didn't have Exif info, or it got clobbered by ...
Viola-Jones' face detection claims 180k features
I've been implementing an adaptation of Viola-Jones' face detection algorithm. The technique relies upon placing a subframe of 24x24 pixels within an image, and subsequently placing rectangular features inside it in every position with every size possible. These features can consist of two, three or four rectangles. The following exampl...
Automatic font recognition with Python
As you may have heard of, there is an online font recognition service call WhatTheFont I'm curious about the tech behind this tool. I think basically we can seperate this into two parts: Generate images from font files of various format, refer to http://www.fileinfo.com/filetypes/font for a list of font file extensions. Compare submit...
What are the algorithms used behind filters in image editing softwares?
For example: What algorithm is used to generate the image by the fresco filter in Adobe Photoshop? Do you know some place where I can read about the algorithms implemented in these filters? ...
Computing object statistics from the second central moments
I'm currently working on writing a version of the MATLAB RegionProps function for GNU Octave. I have most of it implemented, but I'm still struggling with the implementation of a few parts. I had previously asked about the second central moments of a region. This was helpful theoretically, but I'm having trouble actually implementing ...
C# - Multi-touch help? USB web cam input? Image Analysis?
I am trying to make a DIY touchscreen and would like to enter it into the local science fair but wanted to do it on the programing aspect of Multi-touch. My problem lies in that i have never worked with analyzing images (from a USB based web-cam). I would like to do this project in C# if possible (C++ - if worst comes to worst) I need...
Very fast memcpy for image processing?
I am doing image processing in C that requires copying large chunks of data around memory - the source and destination never overlap. What is the absolute fastest way to do this on the x86 platform using GCC (where SSE, SSE2 but NOT SSE3 are available)? I expect the solution will either be in assembly or using GCC intrinsics? I found...