In general, image processing is any form of signal processing for which the input is an image, such as a photograph or video frame.

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22 views

Make a movie from multiple images in MATLAB

I have 10 images in the folder say "D:\images\" named as frame1,frame2,...,frame10. I want to make a movie from the color images with frame rate as per choice.Also i want to save created video file in ...
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9 views

Tile (small image segment) clustering algorithm

I am the author of an open source program: Retro Graphics Toolkit you can find out more here https://github.com/ComputerNerd/Retro-Graphics-Toolkit Retro Graphics Toolkit targets older game consoles ...
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0answers
14 views

What is the implementation of a low-, mid- or high tone dodge or burn in the GIMP?

In The GIMP, and also in photoshop, you have the DODGE/BURN tool to enhance colors in shaded or highlighted regions, which would otherwise be blackish or whiteish. I found empirically that this filter ...
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1answer
33 views

How to detect a inhomogeneity region in image

I have an image that includes object and background. However, the object appears some inhomogeneity region due to illumination. My work is that how to detect inhomogeneity region. Which is feature can ...
6
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2answers
72 views

What's the underlying algorithm for detail-preserving upsampling in Photoshop CC?

The detail-preserving upsampling algorithm in Photoshop CC is truly amazing. It can upscale any image while preserving details in almost real-time. And I truly wonder how it is implemented. I've ...
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39 views

image 2-d real cepstrum with DFT ? ifftshift needed?

this is my testing image,it is taken from this paper: I tried to transform it into its real cepstrum domain with this simple matlab code: cepstrum_img=ifft2(log(1+abs(fft2(img(:,:,1))))); ...
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21 views

Visual regression test - Extract elements of GUI-Screenshot - MSER OpenCV

For a visual regression test I need to compare screenshots of webpages (different release-versions). I started with pixel by pixel compare. Actually I split the screenshot in different parts (maybe ...
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2answers
80 views

Draw outline of a text in an image

I need to draw an outline of text in an image. Consider the below image as an example. Can anyone suggest me a direction to achieve this? I don't have experience in image processing. Any tools/lib ...
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3answers
39 views

Camera Calibration using Single Input Image

Given a camera, permanently located at the same position, angle and distance from what is being captured, and a single calibration image ( a row of vertical lines [ | | | | ] ), how would one go about ...
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34 views

What is purpose of correlation kernel? IIs it high pass filter or low pass filter?

I am research about correlation kernel and I have some questions that need your help. Let see the pp. 3302-3303 in the paper: Changyang Li, et al., Robust Model for Segmenting Images With/Without ...
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39 views

Find and track deformable curve in noisy images

I need to find and track the location of the bottom of multiple deformable curves within a sequence of images. The images are taken roughly 5 seconds apart and there can be considerable deformation in ...
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16 views

object detection in image in matlab

I have two images ; 1. Penstand with pens. 2. Penstand with no pen is there. Now my issue is, there is any code in matlab to know: There is no pen in Penstand OR There are pens in the Penstand. ...
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47 views

Train a Cascade Object Detector in MATLAB

I am trying to train a cascade object detector in MATLAB using the built in functionality from the Computer Vision Toolbox. I’ve taken 500 photo’s of the sole of my shoe. Every photo is taken from ...
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1answer
50 views

Find the centre of circle and max and min radius [closed]

I need to find the centre of this near circular image and also calculate mean radius, Max radius and min radius. Please help me out.
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2answers
42 views

As DCT does compaction of energy, can we say IDCT does energy spreading?

Like energy compaction transforms, the inverse transforms like IDCT are energy spreading transforms?
2
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2answers
76 views

Count objects in the image

How an algorithm can be developed to count numbers and bolts in the image below.
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2answers
40 views

What is 'energy compaction' in simple terms?

This is my understanding of 'energy compaction' and want to know if it is right. Take a vector. The energy of the vector is the sum of the squares of its elements. If A is the transformation matrix ...
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0answers
12 views

Ultrasound generation using field program II

I want to generate a synthetic Ultrasound image for the purpose of reference image for developing speckle noise reduction algorithms. I wanted to know how field program -II can be used with matlab ...
4
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2answers
188 views

Image Processing: Flatten a 3D Ball

There are many descriptions of how to turn a 2D image into a 3D one, however I want to do the opposite, in particular to a ball. As an example, consider the following ball: If only the (relatively) ...
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1answer
36 views

Using ROC curves for comparing the performance of SIFT and SURF

I want to compare the performance of SIFT and SURF against some standard image set. After a bit of research, I found that ROC curves are one of the best ways to do this task. In order to plot ROC ...
2
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1answer
83 views

What is correlation kernel and compare with gaussian kernel

I read a paper that said about correlation kernel that defined: $$W(x-y)=(α/1+d(|y − x|))$$ where $α = (\int(1+d(y − x)dy)^{-1}$, $(d(|y − x|))$ is spatial Euclidean distance from the central pixel. ...
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1answer
61 views

2D FFT of image and sharpness

I'm trying to make some simply autofocus algorithm for my device and pretty confused with 2D FFT results. As I know for now - number of high-frequency's components in 2D FFT will say me that image is ...
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0answers
41 views

Interpolation methods for radar and acoustic imaging

A) What are the most common methods used to remap data for current generation imaging radars and acoustic sensors? B) What are some of the pitfalls in these methods? For example, in the past, at ...
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1answer
48 views

fast 2D cross correlation algorithm

I want to match a small template to a larger image, that the distance between the template and the subimage with the same size of the template is minimized. It can be solved directly or by applying 2D ...
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0answers
15 views

Fastest implementation of Features from Accelerated Segment Test (FAST) algorithm

I understand that there are different implementations (both in software and hardware) of the FAST algorithm. What is the fastest implementation of Features from Accelerated Segment test (FAST) ...
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1answer
27 views

Relationship between sensors and materials in terms of electromagnetic spectrum

The following text is from Digital Image Processing(Gonzalez and Woods)[3ed, Ch 2.2,p46] If a sensor can detect energy radiated by a band of electromagnetic spectrum, we can image events in that ...
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1answer
20 views

How to generate an image with certain clusters using K means clustering in CIE a*b domain?

I am working on building detection from aerial images using Image Processing in MATLAB. I am doing an image segmentation based on the local homogeneity of image. I want to apply K means clustering ...
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1answer
84 views

Zernike Moments' implementation in OpenCV

The reason why Hu moments were implemented in OpenCV and why Zernike moments were not implemented is looking like their performance similar as stated in this paper. As stated in the paper Zernike ...
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0answers
85 views

MPEG-7 descriptors' implementation in OpenCV

I'm looking for implementation of MPEG-7 descriptors which are compatible with OpenCV's recent versions and containing "region-based shape descriptor ART(Angular Radial Transformation)". I ...
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0answers
111 views

filtering out specific waves in scattering pattern

I have the following (experimental) image, with its correponding raw data in .csv format here. The pattern represents the scattering of a laser field off a point defect located in the center. One ...
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15 views

After detection of veins, how to calculate the length of the particular veins as shown in the image?

This is a follow up question from this question. Please see this question for more details. I want to calculate the length of the veins as showing red circled in this below picture.
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32 views

How to get the quaternionic analytic signal of a image?

The 2D discrete image signal's quaternionic fourier transform can be described as F(u,v), and its 2D analytic signal often be described as: $$ F_q(u,v) = (1 + \mbox{sgn}(u))(1 + \mbox{sgn}(v)) F(u,v) ...
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18 views

What data of images are given to kmeans clustering in matlab?

I am having 100 images in my database. I am using those 100 images as both training set and also test images. I have to make 5 clusters. I am using eigen faces (PCA) for feature extraction. What data ...
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1answer
60 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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2answers
87 views

Image Reconstruction:Phase vs. Magnitude

Figure 1.(c) shows the Test image reconstructed from MAGNITUDE spectrum only. We can say that the intensity values of LOW frequency pixels are comparatively more than HIGH frequency pixels. Figure ...
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1answer
37 views

How to do Finger Tracking which is occluded by an object?

Basically I want the hand gesture recognition even when I have an object in hand by using a camera (MS Kinect) in front. My fingers are not visible directly to the camera due to the object. For ...
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4answers
1k views

What are the audio equivalents of images like “Lena”, “Mandrill”, and “Cameraman”?

I don't know what to call these images, but they're very often used in the image processing world as standard examples to show the output of a particular operation. Here's a link to the page ...
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1answer
46 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
20 views

Fusing motion and color in particle filter

I am trying to implement particle filter to track a car bounded by a box. First i used color histogram as my likelihood function and implemented PF, where i was using the bhattacharya distance to get ...
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1answer
19 views

Is there two Types of Scale Space in SURF algorithm?

I couldn't figure out below paragraph on SURF paper and hope that someone can help me to understand it. Bay H., Ess A., Tuytelaars T. Van Gool L. - Speed-Up Robust Features (SURF), page 4, ...
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0answers
26 views

State of the art in pose estimation for human segmentation from video

I'm currently working on accurate segmentation of a human from his background in video. Most of the popular approaches I've some across formulate the segmentation as an energy minimization problem, ...
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1answer
40 views

Can SIFT run in realtime?

What is the best possible runtime for extracting SIFT keypoints and Descriptors? I know it depends on #keypoints extracted. So, say for image of size 640x640, the code that I have been using requires ...
0
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1answer
34 views

How are phase values able to capture motion from video?

I know that the phase spectrum contains most of the structural information about the image importance of phase. But I want to know more about importance of phase spectrum related to video signals. I ...
0
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1answer
13 views

How to turn off calculating pyramids during image processing?

I am using Erdas 2014 to run a 5x5 focal median filter on a batch of images (Raster Tab > Spatial > Focal Analysis (batch)). These images will eventually be resampled to a different pixel size, and ...
2
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0answers
38 views

Is it possible to decompose an image into basis images using MATLAB?

I have read that: Using Fourier decomposition any arbitrary image can be represented as summation of orthogonal basis images. I want to see the basis images for any image say Lena or ...
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1answer
37 views

Image processing and Camera Calibration

I have several related questions about camera resolutions. If I calibrate my camera to a particular resolution say 640x360, can I use it for another resolution like 1024x768? Also, I want to know as ...
2
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1answer
50 views

Planar Homographies in MATLAB

I have taken an image in height 2 meters of the ground as the original image and I want to simulate another image in 50 cm's of the ground, such as the simulated image. The focal length of my camera ...
2
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1answer
56 views

How do we distinguish between Image Recognition,Detection and Segmentation?

I am reading image processing book.while reading i am getting terms like image detection,image recognition and image segmentation. it seems that all above terms are one and the same.i am totally ...
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2answers
79 views

Ship/Boat Detection

I want to do boat detection in almost real time around 2-3 frames/sec and my computation power is not very high. I want to keep the computations as low as possible. Which is the best method to do it? ...
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2answers
54 views

How to proceess Image with curved corners and edges to give sharp Corners?

I have several Images of shape H, F, I, L.. which have curved corners. How do I process them to give sharp right-angled corners? I tried approximating them with inner rectangles, but this takes a LOT ...