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49 views

detect pattern of noise / sound from pcm data

First of all, I'm very new to this field, I've never learnt anything related to sound processing. So I have a case that requires me to detect noise inside audio files (16bit 8khz mono wave file). ...
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0answers
7 views

Harris / Plessy Anisotropic response

Harris and Stephens states that they avoid the problem of anisotropic response: "all possible small shifts can be covered by performing an analytic expansion about the shift origin": Where the image ...
1
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1answer
29 views

Moravec, Harris noisy window

Harris and Stephens writes about the interest window of Moravec: "The response is noisy because the window is binary and rectangular", and suggests applying a Gaussian window. My Question: Why is the ...
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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
8 views

Training an object detector using “object present/absent” labels on image

I want to know the generic name for this technique of object detection: You're given a set of images labeled as "containing a cat" or "not containing a cat", and with this information you train a ...
1
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1answer
74 views

Computer vision, Coupon code detection, sugested algorithms

The telecommunication operator in my country has coupons that used to recharge the balance I want to develop an Android application, that with the camera can take the scratched number and recognize ...
1
vote
1answer
162 views

Baby Cry Sound detection

I wanted to write a code to detect baby cry sound. I am using Windows as platform. Presently, I am able to get audio samples and its frequency plot(using FFT) but not sure how to proceed forward. I ...
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0answers
120 views

Correlation between two graphs in Matlab

I am trying to make a system that detects footsteps. First I filter and decimate the original signal, then I make a convolution between the filtered signal and a single footstep, then I extract the ...
3
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2answers
87 views

Key detection Dance Music inaccuracies - matlab

I have been working on a project with a vide variety of functions for DJ'ing. I am nearing the end, however, the accuracy rate on the key detection part of it is not pleasant when fed tracks of Dance ...
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0answers
69 views

History of emotion (or affect/prosody) recognition (or detection/analysis)?

I want to know how and why emotion recognition started. What I've come up with so far is an article from 1995: McGilloway, S., Cowie, R., & Douglas-Cowie, E. (1995). Prosodic signs of emotion in ...
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0answers
58 views

AR-like marker detection

Let's say I have a grayscale image in which I wish to detect (and later identify) a marker. It is also my task to construct an appropriate marker. As image is grayscale that means the marker should ...
1
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1answer
259 views

Efficient Marker Detection for Images

I need to detect a known number of simple markers (chessboard patterns) in a color image efficiently. I implemented normalized cross correlation (NCC) as a pixel shader via WebGL since I need this to ...
5
votes
1answer
336 views

Suggested Preprocessing methods for OCR on Circular Images

Hello this is my sample image I am going to do real time character detection on images like that. I've tried SURF, SIFT, MSER and template matching on original image without any preprocessing. I can ...
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1answer
155 views

Stopping Viola Jones Face Detection early

I want to try to improve an image processing technique for finding faces in images. I want to stop the Viola Jones face detector before it finds all faces, and do histogram equalization and other ...
2
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0answers
368 views

Why is LBP generaly faster than HAAR?

I am digging into Haar like and LBP features. More precisely its implementation in OpenCV. Every article or forum entry I found states, that LBP is faster than Haar. My local tests also confirm this ...
5
votes
3answers
262 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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2answers
103 views

Ship detection from aerial image

I have an aerial image, like this I want to detect the outline of the ship without shadow. How can I do it? I tried threshold in both graylevel, RGB and HSV. It doesn't work perfectly.
2
votes
1answer
967 views

An alternative algorithm for blob detection

Here's a sample image of my experiment which is to be processed for finding the information of all the blobs (centre, dimension etc.). Basically the image contains some noise, few bold lines, and of ...
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0answers
76 views

non linear equalizer vs linear equalizer

i understand that there are linear equalizers such as MMSE and ZF, however there are also non-linear equalizers such as MLD. i would like to know what is the difference between a non-linear equalizer ...
2
votes
0answers
163 views

Detect Ground Plane

I am trying to detect a crosswalk pattern on the road by using Hough transform, and then selecting lines that separate between black and white regions in a binary image. The stripes are detected fine, ...
2
votes
2answers
535 views

Minimum size for positive samples for HOG (Histogram of Gradient) detector training

I'm going to train a HOG detector for detect objects (pedestrian head) with SVMLight library. But my question is not about implementation. I'm wondering how to collect samples. I have to use some ...
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2answers
5k views

How to Count the number of People in a room using CCTV Camera feed?

I am trying to find out how can I count the number of people in a room using the feed coming in from a CCTV camera fixed in one of the top corners of the room. The number of cameras can be 2 at max ...
2
votes
2answers
2k views

Note Recognition Software

I'm wondering if anyone knows of any open source solutions to note recognition. I'm planning on building a program for online sheet music, which recognizes your notes, and tries to tell you what you ...
5
votes
1answer
182 views

Detecting the original bandwidth of upsampled recordings

I have a set of recordings sampled at 16khz, but some of them are upsampled from 11khz and some from 8khz. Quite some of the recordings are noisy. What is the best way to classify the recordings ...
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0answers
674 views

Help in Retraining a HOG Descriptor using SVMLight

I am currently trying to count cars using OpenCV 2.4.4 with a HOG descriptor. Because a model for car detection is not available in OpenCV, I am creating my own model using SVMLight and a dataset of ...
4
votes
1answer
152 views

How to detect underdamped harmonic signal?

I would like to ask what could be the easiest way to detect the presence and beginning (no more, no less) of under-damped harmonic signal in a collect of ultrasound data. I have some acquired data ...
1
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0answers
51 views

Searching for image samples in order to create custom classifier

I am training a classifier of my own, specifically for detecting body arms. According to the training process I have to provide positive samples and negative samples, wich will be used in the ...
5
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0answers
96 views

Filtering Corners Detected on Multiple Scales

I made a multi-scale Harris corner detector (inspired by MOPS) which is simply a Harris corner detector performed on several scales (i.e. subsampled versions of the same image). This effectively make ...
2
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1answer
1k views

Understanding Integration Scale in Multi-Scale Harris Corner Detector

I would like to improve a simple Harris corner detector by adding more scales. I don't need scale-invariant interest points, just to detect more points by processing more scales. The Wikipedia says ...