is a system of grouping objects of study or observation in accordance with their common features. The classification problem is a formalized task in which a set of objects (cases), separated in some way to classes.

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15 views

Support Vector Machine is unable to recognize the digits in images properly

I am training a SVM on MNIST Handwritten digits database to make a basic digit recognizer. It is able to recognize digits easily on some standard images I took from a source. I then captured an image ...
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2answers
38 views

best similarity measure for audio classification

I'm doing a project on audio classification, mainly focused on Bird sounds. I would like to know which is the best similarity measure that I can adopt to check test signal with training data. I ...
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1answer
17 views

Should I use CV_HAAR_SCALE_IMAGE while using LBP CascadeClassifier?

I trained a cascade-LBP to detect Lollipops with 1000 images, now I'm trying to "adapt" the openCV HAAR-Cascade example to use my LBP trained .xml but I'm not sure about the "HAAR_SCALE_IMAGE" flag, I ...
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1answer
15 views

How does the PASCAL VOC challenge evaluate the task of object detection?

I fail to understand the evaluation parameters like true positive, false positive and false negative in detection and classification tasks. can anyone help me to figure out what does each of these ...
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0answers
12 views

what is near-duplicate detection?

Literately, Near-duplicate detection is for finding very similar image in application where the main goal is finding violated copyright material. but what does this term mean when it comes to image ...
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1answer
61 views

How we calculate Precision-Recall Curve?

As far as I know, precision and recall are two single values. How we can plot a curve from these two single values? I think I should calculate a set of values for each of them but how? afterwards, ...
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0answers
71 views

Using MFCCs in kNN classification

I'm working on adding MFCCs to my kNN classifier. Originally my kNN classifier was using the zero-crossing-rate, centroid, bandwidth, skew, kurtosis. This was about 80% accurate for drum tracks using ...
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0answers
31 views

Supervised instrument recognition

Is it possible to use NMF for a sort of supervised polyphonic instrument recognition? I have training data for a timpani and training data for a bongo (or a bongo, snare and box drum). How can I ...
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0answers
11 views

Global partition of image sets using neighbourhood measures

I have the following general problem, I presuppose an image is the addition of $K$ other images $$f(x) = \sum_{k=1}^{K} f_k(x)$$ but I don't know what they are. At each point in an image I obtain ...
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1answer
58 views

Identify large solid color areas of image

This is a simple image classification problem. I want to categorize jigsaw puzzle images to difficulty levels (e.g, easy, medium, hard). I want to develop an simple algorithm for this classification, ...
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1answer
50 views

Understand about maximum a posteriori probability (MAP) in classfication task

I have a 2D image defined on a region $\Omega$. Let $I: \Omega \to R$ be a gray image. Assume that the region can be separated into $N$ sub-regions $\Omega_i$ such that $$\forall i,j=1... N:\Omega_i ...
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0answers
16 views

Common spatial patterns explanation

Can anyone provide a lay explanation of what common spatial patterns are designed to do in EEG/BCI work? From what I understand, it is similar to PCA in that given 2 classes, it attempts to find a ...
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1answer
69 views

How to use ImageNet Database in Matlab [closed]

How to use ImageNet Database in Matlab for object classification or recognition? I didn't find any tutorial which could practically tell me how to train images on ImageNet database and classify the ...
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4answers
147 views

What kind of features can I extract from this signal

I want to monitor (automatic-)gearbox failures on some vehicles. For each vehicle I have a captured signal representing the selected gear at each one millisecond. An example of two signals are shown ...
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0answers
45 views

difference between CSP and LDA

I don't understand what is the difference between linear discremenant analysis and common spatial patterns techniques. Both of them is based on seperating the data of each class according to their ...
5
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2answers
51 views

Finding filaments in high dimensional space

I have unit vectors in a high-dimensional space (~300) that are non-uniformly distributed over this hypersphere. There is physical meaning when the vectors are clustered together, but I'm ...
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3answers
73 views

What is a good way to distinguish aircraft noise from other sounds?

The FAA's NextGen routes, which were modeled, not measured, have created a bunch of aircraft noise for tens of thousands of people. I want to make it easy for those people (including me) to buy a ...
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2answers
67 views

Can software distinguish between different musical instruments

If possible, I would like to write a little script that can identify different musical instruments from just a recording. Apart from variations of amplitude and frequency over time (which can be ...
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1answer
91 views

How to emulate human sound recognition

A person can recognise a large variety of sounds and fairly subtle differences in sound, even if they have only heard the sound once. Is it possible to recreate this with software, and how? ...
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0answers
99 views

How to determine the order from Auto-Regressive model in Matlab?

I have time series vibration signal recorded for 10 seconds. I segmented the vibration signal into a number of frames. I need to use an Auto-regressive model for this signal. AR model is used to ...
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2answers
118 views

How can I classifying this License Plate images? Matlab , LPR ,

I want to perform automatic character recognition on licence plates. One of my preprocessing step is binarization. However I have four different class of images and I have to use a different automatic ...
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0answers
244 views

Feature Extraction from Accelerometers for classification

I am looking into algorithms/techniques for feature extraction for accelerometer data - to then be used in classification. FFT is incredibly popular, however would this work on accelerometer data? ...
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0answers
94 views

How to use weka for multiclass classification with intersection kernel?

Can anyone please explain to me how to use weka for multiclass classification with histogram intersection kernel.I need to classify bike,car and flower images.
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1answer
40 views

What is the official definition of a feature in signal classification?

Nowadays read any paper or reference on signal classification scheme you would invariably come across the term "feature". What does feature mean exactly? What is considered a time domain feature, what ...
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3answers
127 views

Need critical help: How to detect and distinguish two very similar looking signals?

Hi guys I have a really tough signal processing question here. How do you detect and distinguish two very very similar looking waves? I need to distinguish between these two signals for an online ...
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1answer
100 views

Classification from a feature vector

I'm quite new to this; I'm try to classify textures as defective or non-defective. I've used a Gabor filter bank with Matlab which outputs a column vector of the Gabor features of an image. I have a ...
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3answers
1k views

What are characteristics of shadows in an image given an outdoor setting from an image processing point of view?

I'm wondering what basic characteristics of shadows are. I'm looking from a camera image/video processing point of view. I'm considering the case of an outside scene in direct sunlight. These are the ...
2
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1answer
37 views

Pyramid Match Kernel: How to fit grid around data points?

I am planning to use Pyramid Match Kernel method for object recognition from depth images: I am going to extract a set of feature vectors $x \in \mathbb{R}^d$ for each object instance and then I want ...
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0answers
31 views

Good color distance metric for classifying color pairs

I have some two tone origami paper. This particular paper comes in six types, each with a different pair of colors. Here's an image that shows all six: Given a picture of one of these sheets, I ...
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1answer
64 views

Classifying animated GIFs as animation or film

Is there any known way of differentiating between frames of real footage and animated content? It seems like there's probably range of colors more likely to appear in a histogram for real footage, or ...
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1answer
43 views

Binary classification of grayscale image with little texture

I want to carry out a binary classification/segmentation on a grayscale image with very little texture. The only prior knowledge that's supposed to be available is that the object of interest is ...
5
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3answers
263 views

How to classify accelerometer data?

I am trying to detect if a car did accelerate or did brake by using the accelerometer of the iPhone. In the figure below I plotted the collected data. (To collect the data the phone was laying flat ...
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1answer
46 views

How to choose the number of codewords in bag of words model

In the bag of words model, generally is it better to have more codewords or less? For example, if I have 1000 x 20 raw features, then what would be good value for codebooks? I am thinking of smaller ...
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0answers
54 views

Comparing two signal outputs from two clients on a networked computer game to identify lag

Basically, I'm running a server and two clients of the Unreal Engine and trying to figure out if there is lag in player movement on one of the clients (the clients are different in way that's not ...
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1answer
2k views

Feature extraction for sound classification

I'm trying to extract features from a sound file and classify the sound as belonging to a particular category (eg : dog bark, vehicle engine e.t.c). I'd like some clarity on the following things : 1) ...
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1answer
76 views

Missing Data in Machine Learning Classification

I have a training set of 4000 for ML with 36 features, two-class classifier. -But consider that due to some discrepancy feature no. 25 is missing for half of the data. But during data ...
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0answers
105 views

OpenCV: Is NormalBayesClassifier::train function running ok?

I am have the code from here. I have changed the images with some of my own and I have seen that SVM is not working. That is not a problem because I have found on ...
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2answers
346 views

Using ICA on EEG signals for feature extraction

I am attempting to use ICA (FastICA via scikit-learn) on EEG signals from seven electrodes per subject for feature extraction and identity classification – that is to extract signal which is related ...
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3answers
3k views

Best way to remove unwanted region from image

I am finding the techniques to remove unwanted regions (small dots) from image. I have an image that includes object and some unwanted region (small dots- see first image). I want to remove it. Hence, ...
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1answer
163 views

What Matlab Classifiers to use

I'm currently trying to decide what classifier to use for my snore detection algorithm. Which uses some features like Zero cross rating, frequency band energy, first formants... The classifiers which ...
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3answers
166 views

What does natural scene image data-set mean?

I came across a paper that is trying to classify and detect object(s) present in what they call a natural scene data-set. They have images containing objects like cars, bikes and people. Can anyone ...
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0answers
55 views

Frequency contour cross-correlation

I'm trying to segment (or extract) different calls from a spectrogram. My current method, calculates a threshold value (variance) and then using RMS can detect voiced/unvoiced signals: $$ Thres = (1 ...
1
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2answers
188 views

what is the output of BoW after an image has been trained with SIFT algorithm and k-means

SIFT algorithm provides a 128 dimensional feature vector that is used for image classification.When all the interest points(key points) are taken together and K-means clustering is applied,the image ...
3
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3answers
594 views

Detection of wobbling sound with rising notes

In an audio file I would like to find calls of a specific bird specie, one that makes wobbling sound with rising notes. Can you recommend what would be the best audio feature to calculate in time or ...
1
vote
2answers
66 views

What's a good classification algorithm for a large amount of classes?

My requirements are these: Fast classification of vectors of length 100 to one of 30000 classes Iterative learning (can improve the model after it was first learnt) Preferably available ...
3
votes
2answers
194 views

Guidance/Brainstorming for a mapping/classification problem

I'm quite new to machine learning/data mining and I'm struggling to find the correct path for my problem and would appreciate some guidance or criticism of my proposed solution i.e. is there a ...
0
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1answer
126 views

Music/Speech Classification: How are frame based features used in a feature vector?

I'm a little confused on how frame based high dimensional features such as mfcc's and bfcc's are applied in the classification of musical instruments. Are statistical measures of the features used ...
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3answers
268 views

What is the standard way to handle images of different sizes for classification?

I'd like to create an image classifier that takes a set of labeled images and creates a classifier to be used on some unknown images. Most of the examples I see assume all images are the same size (m ...
3
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2answers
2k views

Mahalanobis vs Normalization+Euclidean

I'm using a set of features extracted from a signal for classifying the data window with KNN algorithm. Since the features have different value ranges, their influence on distance calculation is ...
3
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3answers
286 views

Low recognition rates using GMM for image classification

I want to use GMM for image classification. So, I have extracted SIFT features from each image in the corpus. Then, I apply EM algorithm to learn GMM parameters (I have coded it in matlab). I get ...