This tag covers signal processing where input is an image, such as a photograph or video frame and the output could be an improved or altered image, parameters related to the image or information about features within the image.

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1answer
48 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 ...
1
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1answer
45 views

Longest line inside of 3D object

I have a 3D object which I have segmented and represented as a 3D binary array. I need to find the longest line which fits inside of the object in three dimensional space. What would be an efficient ...
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1answer
26 views

which spatio-temporal properties does dynamic textures exhibits?

know that dynamic textures are spatially repetitive and temporally varying patterns. 1.I read one sentence in one paper i.e. They are sequences of frames exhibiting certain stationarity properties ...
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0answers
22 views

Impact of different padding schemes in Frequency domain image filtering

I understand, that image padding is necessary in order to prevent wrap-around effects due to circular convolution. My set of questions are related to different padding schemes. Zero Padding is easy ...
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2answers
72 views

How can I go forward with this image processing task?

0 down vote favorite I am totally new to Image processing. I just started my Master thesis in the area of Computer vision and Machine learning. My background is Informatics. Now, my first task is to ...
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0answers
24 views

what is the starting time of FRAME VALID in CMOS MT9V131 Sensor?

I am going to start my project with CMOS MT9V131 Image sensor. In that, data output timing diagram, I have some doubts. Actually, I am going to interface this sensor with LPC1768 by the use of I2C ...
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1answer
74 views

What is the Difference between Texture and Image?

I am beginner in the image processing I want to know what is difference between Texture and Image? or whether they are same? can anyone explain it. Also,if i want to do texture segmentation,can i ...
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0answers
26 views

What is weakness of entropy image

I often see that entropy is used in image segmentation area. Hence, I have a question about entropy. What is weakness of entropy image. Which case is fail when apply entropy image? Thank you so much
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1answer
36 views

Thresholding a difference image with a very high kurtosis

I have an difference image produced by substracting two images of a certain location taken a two different time steps. The resulting image of this operation shows a histogram with a very large peak ...
1
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1answer
64 views

Dynamic Textures

i know that texture refers to surface characteristics and appearance of an object given by the size, shape, density, arrangement, proportion of its elementary parts. But i am more interested in ...
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0answers
29 views

Box filter approximations for oriented gabor filters

I'm currently working on a library to generate synthetic fingerprints using the SFinGe method (by Maltoni, Maio and Cappelli) link ...
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2answers
42 views

Image warping - how to proceed

I'm studying image warping and I'm unsure how to warp a starting rectangular image into another image where the box corner points have been changed as I want: (image from ...
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0answers
15 views

image restoration using known noise variance

I want to design filter for image restoration. The noise varince of the noisy image is estimated by me. Which method can I use to de-noise the image so that the filter passes only the pixels having ...
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0answers
31 views

How many way to reduce overfitting problem of Linear classificationH

I am working in linear classification such as y=ax+b. where x={x1...xn}. But the method has weakness that is overfitting problem. Could you suggest to me one method or one way to reduce overfitting ...
0
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1answer
32 views

Linear classification and overlapping problem reduction

I am study linear classification(Y=aX+b) But it is still weakness that is overlapping problem. Could you suggest to me how to reduce overlapping problem in linear classification or how to find these ...
0
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1answer
31 views

Image and video processing in matlab

I have been working on Digital signal processing since Feb-2013. I have good command over it. Now I want to expand work in field of IMAGE and Video processing. Please suggest me best practical guide ...
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2answers
49 views

Adaptive gaussian filter for noise image

I am looking for methods to enhance noisy images, where: some pixels in the image are very noise, some other pixels do not contain so much noise. My first thought is to build an adaptive Gaussian ...
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0answers
21 views

How many features of given image

assume that I have a set of image and segmented image of a object in image (training set). Now, I want to measure features of object in image based on the training data. But I don't know how many ...
0
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1answer
46 views

Histogram matching of two images using cdf

I have already calculated the cdf values of each image now i have to map the reference image values to target . I cannot use histogram equalization or interpolation I simply have to map them . ...
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2answers
51 views

how to make image editing filters

I am trying to make filters for days but now I just want to know the experience of others rather than go on to wrong way and finally decided to put my query over ...
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0answers
22 views

How to apply dictionary learning to several images?

I'm implementing a dictionary learning algorithm for doing sparse coding on images and I have a problem how to learn a dictionary corresponding to several iamges. Let’s say X is the data matrix. If I ...
0
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1answer
36 views

Computer Vision Libraries for PHP

Are there any computer vision libraries in PHP, or any server-side programming languages? If not, maybe we can make a list of some -already implemented- methods (Viola Jones face detector, landmark ...
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0answers
37 views

Fourier Transform in 2D? (image processing) [duplicate]

In audio signal processing, Fourier Transforms are widely used to convert the mono-dimensional signal, expressed in time, into the frequency domain. It is not clear to me how this is extended to the ...
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0answers
38 views

Image processing(JPEG)

write an m-file that will take the"cameraman" and produce a image quality or difference matrix for spectral selection method.The image properties are a sfollowings: For spectral selection: image1:DC ...
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2answers
90 views

Poisson noise and curve fitting - denoise first?

If I have an image that is severely corrupted by Poisson noise, and I want to fit a function to the image, is it "better" to attempt to denoise the signal first before fitting, or should I move ...
0
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1answer
101 views

Drawing in images

I want to develop a procedure to remove some inpainted text from images, i.e. I have to estimate the inpainted pixels. I will do that with first an imputation step and then applying SVD (and perhaps ...
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0answers
26 views

Spatial Expectation Maximization matlab

I am looking for the way to implement spatial Expectation Maximization matlab code. Because traditional EM cannot handle with noise image. Hence, I want to find improved EM matlab code. Could you ...
2
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1answer
111 views

Which method to remove small unwanted region and fill holes

I have a hard problem that need your help. I have a binary image that maintains some unwanted region (small white dot) and hole regions (in figure 1).My idea is that the first I will remove unwanted ...
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0answers
89 views

How to make color balance of photoshop using opencv

I want to make the same thing programmatically like Color balance in Photoshop , like in below image if we have same bar ...
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0answers
41 views

The relationship between zero level set and thickness information

I have one problem that need you help. I am try to find the relationship between active contour and thickness information. For defination of thickness we can find at thickness measuring and active ...
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0answers
32 views

Suggestions based on using IHS transformation on images and optimizing using Least square adjustments [closed]

I have to normalize the image using Intensity Hue Saturation transformation and further use Weighted Least Square adjustments to reduce root mean square error. I want help regarding 1) The above ...
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0answers
73 views

How to segment with false edge in in image?

I try to resolve false edge problem in image segmentation. Let see its defination in Figure. The false edge problem often occurs in inhomogeneity image, especially for medical image. I am finding the ...
0
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1answer
76 views

3D effects like HTC One Dimension plus

Its true that HTC one M8 uses dual camera to achieve the 3D Dimension plus effect, but can anybody tell what is it called, if its a series of image manipulation? Demonstrated here, Video
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3answers
63 views

Trying to translate formula for blending mode

I am using OpenCV C++ for making the blending mode like in photoshop, I want to make overlay mode in it. I search its alternate in OpenCV in which I found this ...
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0answers
36 views

How vibrance method of photoshop work in opencv

Can somebody please explain how Photoshop vibrance function can use in opencv c++ ? so that I may reproduce the same effects in my application. Here is the vibrance ...
0
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2answers
142 views

How to calculate the local gradient of an image in MATLAB

I know that the gradient function is supported by MATLAB, but the local gradient is not, so how do you calculate it? Local gradient is another texture descriptor, which is defined as: ...
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0answers
187 views

Haar wavlet Transform in OpenCV

I am new to OpenCV. I am working on implementation of Haar wavelet transform of an image in OpenCV in C++. Please anyone suggest me how to implement?
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2answers
65 views

measure angle between two lines, can rotation center constraint be used to refine the initial measured result?

I'm trying to measure the angle between two needle positions in an analog meter (gauge). such as: After the image processing of several images, I get the processed image below(a image show different ...
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0answers
14 views

How can I calculate the Gaussian range and space parameters in a bilateral filter?

Let's suppose I have the following [4x10] image: 1 3 4 5 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 1 2 5 3 5 6 8 9 0 0 2 3 4 6 7 8 9 0 8 9 How can I calculate its space ...
0
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1answer
20 views

New capture card YUV 4:2:2 leads to different images

I have just bought a new video capture card whose output format is YUV 4:2:2 (as my old one) and surprisingly when I capture images with both cards I get different results. Differences are very small ...
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0answers
32 views

linear contrast stretching based on minimum and maximum calculation from image histogram

I'm studying Gonzalez image processing book and under the topic linear contrast stretching based on minimum and maximum calculation from image histogram has been ...
0
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2answers
34 views

Need samples of big endian encoded tifs [closed]

Folks I've written a small utility that extracts some (and only some) header information from Tifs. To test it fully I need some Big Endian Tifs, but I cant find any, and I can't find anything to ...
0
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1answer
61 views

Best method to segment a given image

I have one image. I want to segment it by simple approach. Could you suggest to me the best method to segment it? I think one of them is gradient or FCM. But I am not sure. Please see my given image ...
0
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1answer
102 views

What does the 420 means in YUV420?

I'm not sure if is the correct location for ask this question. If not please info me the correct StackExchange site. As this wikipedia page show, there is one YUV format of image as YUV420 and YUV411. ...
0
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1answer
21 views

PNG IDAT specification

I'm going over the W3 PNG specification (creating a PNG library from scratch) and I've finally found how to create a green 1x1 image. Now I'm trying to create a bigger image of mixed Red, Green and ...
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3answers
126 views

What is benefit when convert signed 16 bit to unsigned 8 bit in medical image?

I have an image with its type is 16 bit signed. I see some paper, the author often convert it to unsigned 8 bit. But they did not explain why they do it. Could you explain what is benefit of this ...
0
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1answer
85 views

How to make filters?

I am trying to make filters like sepia filter in my app like other photo editing applications , till now I don't have any idea about it , Can any one help me out ...
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0answers
308 views

Image Processing/Analysis for Eye blink detection

I am working on a eye blink detection project in Matlab. By this moment I have been successfully extracted the images of pupil of eye from the real time video captured via a web cam. But I am stuck ...
4
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0answers
28 views

Meaning of tight frame in the context of texture synthesis

I am currently reading "A parametric texture model based on joint statistics of complex wavelet coefficients", by Portilla and Simoncelli. In this article, they use the "steerable pyramid" to ...
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0answers
52 views

Dice Similarity coefficient for 3D image?

I am want to calculate Dice Similarity Coefficient (DSC) for 3D image. I done it for 2D. But I don't know how to apply it or change for 3D. Could you help me to find the way to calculate DSC for 3D ...