4
votes
Accepted
GPS Coarse Acquisition PRN Codes
I have a PRN generator that I have validated with live captured signals that is available on the Mathworks Exchange site at this address and equally runs in Octave (Update: I also pasted the core of ...
- 55k
4
votes
Accepted
GPS CA Signal Acquisition
What's the maximum residual frequency offset allowable when doing the despreading of the CA code? 500 Hz? Or, what's the SNR loss due as a function of frequency missmatch due to residual Doppler?
The ...
- 55k
2
votes
Scale invariant template matching
To increase the speed, I think the dimensionality of the feature descriptors should be reduced. SIFT feature descriptor is of 128 dimensions.
So you can try PCA-SIFT which reduces the descriptor ...
- 311
2
votes
Accepted
Difference between Generalized Hough Transform and Cross-correlation Feature Matching
There is a big difference: The Hough Transform maps the input space to a parameter space, where the search takes place. This way, the run-time of the algorithm is independent of the degree of the ...
- 5,515
2
votes
Algorithm for Scale Invariant Template Matching
Just wanted to give a little bit of modern answer to this question. In the 'machine learning' sense. Such matching problems are (maybe a little unfortunately) rebranded as one-shot object detection or ...
- 5,515
2
votes
Finding a certain animal from wildlife audio
Template matching is deemed a classical approach to attack this problem. An alternative state-of-the-art method is to use deep learning (CNN) classifier given your data is labeled. However, if you ...
- 589
1
vote
Algorithm to detect tapping-events in an XYZ-signal of an accelerometer
Please consider the following, if you are not familiar with some of the techniques you described
A simple vectorial amplitude + detrend + threshold would be enough to catch most of the taps over a ...
- 1,420
1
vote
Identify and remove repeated audio chunks
What I'd do:
Transform data into a representation that maximizes "similarity" of chunks that are otherwise "alike" but have large Euclidean distance in terms of raw waveforms
...
- 9,242
1
vote
Algorithm for Scale Invariant Template Matching
I believe Haar Cascades(used by Viola-Jones) are inherently scale-invariant. Also severely deprecated by modern Neural Networks, but I know nothing about those. It also doesn't do any OCR - if you ...
- 233
1
vote
Accepted
Algorithm for Scale Invariant Template Matching
If your templates are all based on some kind of text you may use some kind of OCR to match the text itself and not only by features.
Regarding features, you may read: A Comparative Analysis of SIFT, ...
- 20.5k
1
vote
Detect when signal starts oscillating
As far as I can tell from the graph, the variance of the signal goes up substantially under "oscillation" conditions. So, monitor the variance over a rolling window. High variance indicates ...
- 191
1
vote
Matching guitar signal with tablature, near real-time algorithms?
Assuming that the tablature is well defined; let's say it's a MIDI file complete with pitch bend commands. you can make a synthesizer where each note is actually a tracking comb filter tuned to the ...
- 21.5k
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