The tag has no wiki summary.

learn more… | top users | synonyms

0
votes
1answer
46 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 ...
0
votes
0answers
12 views

Normally Distributed Frequency Drift in Signal Processing

I have a synthetic signal and an observed signal that are discritized in time, due to the sampling rate and it is only measuring magnitude. The synthetic signal assumes a frequency while the observed ...
0
votes
0answers
36 views

how to calculate feature points in SIFT?

i wanna know how to calculate key points? im doing it in matlab. when i select 3 DOG(differnce of gaussian) blured image and compared each pixels in the middle image with 26 neighbourhood(including 9 ...
4
votes
1answer
241 views

Ambiguous results of phase correlation in pattern recognition

We are using phase correlation to find pattern on image and what we get is 15% of results is spurious. Ours pattern has 32x32 pixels and image for research has 32x512 pixels. So we put Pattern to ...
2
votes
2answers
441 views

Using DTW on the MFCC's to match a spoken word to a template

I am trying to code a simple algorithm in Matlab that would be used to detect a single word. The goal would be to have a user record the word one time to act as a template, then make the user repeat ...
2
votes
1answer
143 views

how could correlation-based image patches matching works?

In general, correlation-based image matching can be referred to as $$c(I_1,I_2) = \sum_{x \in patch} f(I_1(x), I_2(x))$$ , I do think normalized cross-correlation like $$ncc(I_1, I_2) = \sum_{x \in ...
2
votes
1answer
371 views

Questions about log polar transform

I read various papers about the log polar transform and its application on template matching with images and have some questions: In "Image Registration Using Log Polar Transform and Phase ...
6
votes
1answer
117 views

How to tell how likely a signal is present in another one? (variance unknown)

I know this is probably a simple question, but I haven't been able to find a satisfactory answer anywhere... Say you have a time series signal of finite length N. Call it $y[n]$. It is stationary, ...
1
vote
0answers
372 views

How to recognize a zebra crossing from top view using OpenCV?

How to recognize a zebra crossing from top view using OpenCV? It is not a straight zebra crossing - it has some twists and turns. I have some ideas: parallel line detection, but the available ...
7
votes
3answers
3k views

Scale and Rotation invariant Template Matching

I'm looking for a method for scale and rotation invariant Template matching. I already tried some, but they didn't work so good for my examples or took for ever to execute . SIFT and SURF Feature ...
10
votes
1answer
164 views

Advise on detecting anatomical landmarks in a CT reconstructed volume

I'm trying to automatically detect some medical defined anatomical landmarks in a CT reconstructed volume. Medical doctors use these landmarks to measure some patient specific parameters. I have ...
12
votes
2answers
444 views

Necessary image processing operations before template matching

Well, this may show I didn't take image processing class. I have this template to match an object in images. But real object in images, for example, does not look like that but the second image. What ...