A form of signal processing where the input is an image. Usually treating the digital image as a two-dimensional signal (or multidimensional). This processing may include image restoration and enhancement (in particular, pattern recognition and projection).

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8 views

Image Processing: Difference between SURF and SIFT?where and when to use this algo? [on hold]

Image Processing: Difference between SURF and SIFT?where and when to use this algo
0
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0answers
6 views

What is the difference between Harris Corner Detection and SUSAN Corner Detection? [on hold]

What is the difference between Harris Corner Detection and SUSAN Corner Detection
0
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0answers
9 views

Find input image (ID,passport) in imagesDB based on similarity

I would like to decide if image is exists on DB images (pictures of IDs,passport,Stu. card,etc) I thought of KNN alghorithem that will plot the K closest images. Options for distance metric: 1) sum ...
1
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2answers
49 views

Multi-class Classification using SVM with PCA

I'm doing an image classification task and the number of features of each example image is pretty huge (3,072: # pixels in each image). I'm thinking of using PCA to reduce the # features of each image ...
0
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0answers
18 views

Query on “Deep neural networks for object detection”

I was trying to follow the paper "Deep neural networks for object detection" at http://web.missouri.edu/~hantx/ECE8001/Presentation_papers/Deep%20Neural%20Networks%20for%20Object%20Detection.pdf. I ...
0
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0answers
10 views

Gabor filters: Large variance compared to the mean

I am trying to extract Gabor features from an input image. So, I have setup a series of Gabor filters with different parameters (frequency, angle and standard deviation) and I am convolving each of ...
1
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0answers
36 views

Compare 2D maps

I have a bunch of samples to compare. Each sample is composed of 30,000 cells (dots) for which I computed 2 dimensions (30,000 x 2 matrix). Each dot represent the expression of two parameters for a ...
0
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0answers
7 views

Combining features extracted from different parts of the same image

It is about car identification in images. I have an 64x64 image divided into 16 equal windows. I compute a HoG features algorithm in each one. And I am using the concatenation vector resulted from ...
0
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1answer
30 views

find the optimal correspondence matrix

I have two sets of points and I find with different methods, different correspondence matrices which shows which point in one set correspond to other point in the other set. How could I find the ...
0
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1answer
47 views

how to superimpose two matlab images rigidly transformed to perform a metrics

i got two MRI images on matlab, i need to perform an intensity based registration similarity metrics in order to get a registration. The problem is that, since i got some rigid transformation on one ...
4
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2answers
302 views

What is the difference between ZCA whitening and PCA whitening?

I am confused about ZCA whitening and normal whitening (which is obtained by dividing principal components by the square roots of PCA eigenvalues). As far as I know, $$\mathbf x_\mathrm{ZCAwhite} = ...
1
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1answer
50 views

Breaking black and white captcha

I am looking for a way to break this kind of captcha: I know that there are always 4 digits, in black and white. The image basically consists of an easily recognizable 4-digit code, mixed with a ...
0
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0answers
20 views

Neural Network & Image recognition - preprocessing

I have a project where I´m supposed to recognize ordinary data written numbers (1-10) from images as well as some geometrical shapes (rectangular, triangle, circle, etc.). However, I´m not sure about ...
0
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1answer
32 views

Question of unary term (data term) of the graph cut method

I am trying to apply graph cut method for my segmentation task. I found some example codes at Graph_Cut_Demo. Part of the codes are showing below ...
0
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0answers
18 views

Definition of the deterministic annealing method

iI have ran into a shape matching problem and one term which I read about is deterministic annealing. I learnt that it would help to convert discrete problems, e.g. ...
0
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0answers
14 views

Which terms are more standard: precision and recall or correctness and completeness?

I am familiar with terms like precision rate and recall rate from the machine learning literature, but recently I was reviewing a thesis which used the terms correctness and completeness. A quick ...
2
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2answers
346 views

Comparing two histograms

I would like to know what are the common techniques to compare two histograms? I have histogram of two images and I want to see are they similar or not meaning that is there any correlation between ...
1
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0answers
143 views

Machine Learning Process for detecting edges of overlapping objects with OpenCV

I'm quite new to machine learning and a bit unsure about the whole process and the interpretation of the results. The Task: I have images with some objects of somewhat the same color and shape which ...
1
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3answers
39 views

Computing Image Similarity based on Color Distribution

Image Similarity based on Color Palette Distribution I am trying to compute similarity between two images based on their color palette distribution, let's say I have two sets of key value pairs as ...
0
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0answers
10 views

Dimensionality reduction by predominant component analysis

Does any one know the concept of dimensionality reduction by predominant component analysis. ? This is introduced in one of the scientific papers. Please could any one explain how it works. Below ...
2
votes
1answer
38 views

What do NORB and CIFAR stand for?

The MNIST dataset is a standard benchmark data set of digit images. MNIST stands for 'Mixed National Institute of Standards and Technology'. The NORB dataset is a commonly used dataset of binocular ...
1
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1answer
34 views

Image clustering and Dirichlet process

I am reading a paper about the Dirichlet process and image segmentation. (http://dl.acm.org/citation.cfm?id=2404806) How is (3) below derived? Do any articles or posts explain image segmentation and ...
0
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0answers
29 views

Conceptual question on image pattern representation

I have a basic question regarding pattern learning, or pattern representation. Assume I have a complex pattern of this form, could you please provide me with some research directions or concepts that ...
2
votes
1answer
96 views

Image processing with neural network

I am trying to learn how Neural Network works on image recognition.I am confused that how neural network that how i will give input.My defination is find(track) object in squence of images(particular ...
1
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1answer
44 views

Help in convolution operation

I am stuck in understanding how the output of convolution operation is obtained. Can somebody please show the steps? The question is an image is processed by applying 3*3 mean filter . What is the ...
1
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1answer
106 views

What is meant by binary images of handwritten digits?

I can understand what a handwritten digit is, but what is meant by "binary image"? Can someone explain it? I am studying machine learning concepts. In doing so, I've come across many types of inputs. ...
0
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0answers
17 views

Detecting/recognizing landscape and architecture photographs

I have a large set of photos of various kinds, labeled with some tags but the tags cannot really be trusted (e.g., some portraits will have a tag 'portrait' while many won't, likewise for 'landscape', ...
0
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0answers
56 views

Edge Probabilty Using KL-Divergence Code in Python

Its a little complicated question, so please bear with me. I am doing Image Segmentation using Swendsen-Wang method for Image Analysis./ (stat.fsu.edu/~abarbu/papers/jcgs.pdf) I have to calculate ...
2
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1answer
50 views

Having a Neural Network recreate what it's learned

I've created a basic Neural Network that learns from basic information and can verify whether or not a piece of information matches it's parameters from a match percentage. Conceptually however, I ...
2
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0answers
62 views

Emotion recognition lip zone processing

I want to detect emotions by comparing the cropped lip zone with different templates and output an emotion based on the score. So far I've applied: Normalization Discrete and fast Fourier transform ...
1
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0answers
31 views

Adding errors in quadrature for mean values

I understand that for $ Z = \frac{X}{Y}$, the error in quadrature would be calculated as, $\Delta Z = Z \sqrt{\big( \frac{\Delta X}{X} \big)^2 + \big( \frac{\Delta Y}{Y} \big)^2}$. In my case, X and ...
0
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3answers
28 views

Ressources for image processing

I want to read, study statistically and modify numerical images. During school i used to work with built in functions in MATLAB. I don't have this possibility anymore. Now i want tout resume my ...
0
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0answers
11 views

How should I choose SNR value that the object is recognisable by the human eye from background noise?

I have some images that are made of an object and some amount of background noise. I have sampled the object for example at 40%. So the object is becoming pixelated, then I inject some amount of noise ...
0
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0answers
54 views

Spatial patterns analysis for images

i have done some research about spatial patterns analysis, using some spatial statistics mesures, all the cours that i found talks about spatial statistic in the context of GIS, in the context of ...
0
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0answers
20 views

Pseudoinverse for time series filtering

Suppose I have a few time series, that are strongly correlated to each other, and I consider this to be noisy data. How do I use the pseudoinverse technique from image processing to filter this data?
1
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1answer
201 views

Normalized cross correlation vs Euclidean distance in template matching

What is the difference between normalized cross-correlation and Euclidean distance in pattern recognition? -- especially if we want to do recognition with template matching. I understand about ...
0
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1answer
26 views

Distance Transform In Image?

I understand how to compute Distance Transform for BW image In BW image we can calculate the distance of the pixel with non zero pixel value using Eucledian Distance. But I dont undertand how to ...
1
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0answers
12 views

EnergyThe meaning of these term in Image Processing?

Im newbie in Image Processing field, and I got many term that wierd. There are : Moments Local and global characteristic Energy of Image Color Temperature What each of them represent in Image??
0
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0answers
28 views

Detecting noisy patterns in document images

I am looking for features to extract to distinguish between text objects and arbitrary noisy patterns in degraded document images. This is an example of a document with some parts of noise, I have ...
0
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0answers
19 views

Metric to show the overall similarity between two set of points obtained from handwritten word?

In my case, I would like to compare different handwriting to a template handwritten word, and return a single metric to show how closely the input matches the template's shape. The lines are the same ...
5
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3answers
348 views

statistical method for spatial correlation between images

I am working on analyzing a data set and I was wondering what would be the most statistically valid method of demonstrating that there is a strong spatial correlation between images. I have a data ...
0
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0answers
17 views

Assuming a raster image is a random vector

I am currently working in remote sensing. It is quite common to find that the beginning of the statistical descriptions of techniques used in satellite image processing begin with defining the initial ...
3
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2answers
520 views

k folds cross validation on a multi-class dataset

Cross validation is one of the most important tools because it gives us an honest assessment of the true accuracy of our system. In other words, the cross-validation process provides a much more ...
0
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0answers
9 views

Three categories of spatial relationships

In this paper, the author claimed there are three categories of spatial relations: Topological relations, which remain invariant under transformations such as translation, scaling and rotating ...
1
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1answer
355 views

Variational method — implementation of function gradient for image denoise

I am studying Variational Methods and decided to code a simple matlab implementation of the famous image denoise example: $E(u) = \displaystyle\frac{1}{2}\sum_{i=1}^N (u_i - f_i)^2 + \displaystyle ...
0
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0answers
17 views

Heat kernel and laplacian

Is there any relation between heat kernel and Laplacian? I know what each of them is but I am not sure about the relation between them.
10
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0answers
193 views

Training a basic Markov Random Field for classifying pixels in an image

I am attempting to learn how to use Markov Random Fields to segment regions in an image. I do not understand some of the parameters in the MRF or why the expectation maximisation I perform fails to ...
1
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1answer
64 views

Questions on bag of features methods

I've been studying the bag of features (BoF) methods. I understand the basics and how it's done but I think I still am not good at the details. So here's my understanding of such methods: Suppose you ...
1
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0answers
71 views

Classifier predicts only one class

I was trying myself in kaggle CIFAR competition, I trained lots of classifiers but get the same result/fail (don't know how to treat them), maybe someone could help me figure what i'm doing wrong. ...
0
votes
1answer
162 views

Detecting An Image is Bright or Dark? [closed]

I use Java and I have some PNG images. I want to put a caption on my images. However I want that: if an image is bright I want to put a black text on image and if an image is dark I want to put a ...