Questions tagged [terminology]
For questions about words, phrases and definitions that are specific to signal processing.
89
questions
2
votes
1answer
31 views
Most generally-accepted audio term, for “pre” and “post” lengths of a symmetric filter's impulse response?
Consider a FIR audio filter with symmetric impulse response.
In my case, the filter kernel width is 15 frames on each side (so including the center frame, 31 frames total). When examining the audio ...
0
votes
2answers
50 views
What specifically does PCM refer to?
What specifically is PCM? I've seen it refer to:
the sampling and quantisation of an analogue domain signal into digital samples
those sample quantisations alone in the digital domain i.e. in memory ...
0
votes
0answers
32 views
DFT algorithm designed for a “sample-by-sample” senario
Suppose I have a system that wants to take an input signal (audio in this case) and wants to output a Discrete Fourier Transform of it in real time (ie every sample).
My initial thought is that if you ...
2
votes
3answers
214 views
Confusion understanding digital signal processor?
I am reading wikipedia article about digital signal processor and as shown in end of attached snapshot
." Most general-purpose microprocessors can also execute digital signal processing ...
2
votes
1answer
50 views
Conceptual Questions on Colored Noise Process
I am having a tough time finding answers to some specific questions and finding references where there is information regarding Brownian noise or Red Noise. I'm referring to white and colored noises ...
-1
votes
1answer
49 views
Meaning of monotonic in context of filters?
What is meant by "monotonic" in context of filter
As shown in attached snapshot
2
votes
1answer
61 views
Is linear convolution same thing as aperiodic convolution?
I am reading an online article and what i understood from there is that linear convolution is aperiodic
Is it right?
I have also attached snapshot and higlighted two instances
0
votes
1answer
49 views
Kernel vs impulse response: what's the difference? [duplicate]
I am reading The Scientist and Engineer's Guide to
Digital Signal Processing by S.W. Smith. In Chapter 9: Applications of the DFT in the 3rd paragraph he writes "kernel (impulse response)"
...
0
votes
1answer
40 views
Confusion regarding notation/symbol?
I was reading circular convolution topic from Digital Signal Processing Using Matlab 3rd Ed,by Proakis. I came across a strange term/symbol; I have highlighted it in attached snapshot
I have also ...
0
votes
1answer
136 views
Combiner vs mixer vs coupler?
All these three terms are often used in communication texts and apparently they are some how similar
But what is exact difference between each of them?
0
votes
0answers
10 views
Mutual information smaller on data subsets compared to entire data set
I am estimating the mutual information for a continuous data set using the kNN-based mutual information estimator proposed by Kraskov et al [1].
Lets consider two features $X$ and $Y$, and the ...
0
votes
1answer
43 views
Confusions regarding meaning of “kernel” in signal processing and image processing? [duplicate]
While studying filters in DSP and DIP, the term "kernel" is often encountered
What is the meaning of "kernel" in context of filters??Please kindly explain in simple words with an example
I have also ...
6
votes
6answers
1k views
Meaning of Phase response of a filter? In simple words?
What is meant by phase response of a filter? Often it is associated with restoration of signal shape,so if a filter has linear phase response, its output looks like input otherwise output is ...
1
vote
2answers
66 views
Confusion understanding causality?
I already know the simple definition that causal system is the one that does not depend on future values of input but today i was confused as i came across a new definition of causality after reading "...
-1
votes
1answer
36 views
Confusing regarding triangular wave vs square wave?
I am reading signal processing first by Mcclellan. In chapter 3, I came across the term "discontinous" as shown underlined in attached photo.
Apparently "discontinuous" means having a gap/break but ...
0
votes
0answers
13 views
Is sparse dictionary learning just a subset of non-negative matrix factorization?
I saw some people argued that their method should be called sparse dictionary learning or NMF. What are the differences between these two terminologies?
If the dictionary is given or fixed, the ...
2
votes
1answer
26 views
Describing a certain quality of an image
Generally I guess I’m asking for a source of image processing terminology.
Specifically here I’m trying to find the word for the quality that would identify the main difference between the Mondriaan ...
0
votes
1answer
25 views
Whats the technical term for a filter that allows a non unity stride when sliding it's window?
So a 1D mean filter of size two with a sliding window defined as W below could be considered as having a stride of one.
Wn=(Xn + Xn+1) / 2
Vn=W2n
where as if I were to define a 1D 'stepped mean ...
2
votes
0answers
298 views
Definitions of PSD, ESD and Autocorrelation
This question is going to encompass multiple areas and may not have a single answer but here it goes. I'm trying to conceptualize 3 different concepts and how they relate to each other. These 3 ...
0
votes
3answers
56 views
What word can I use to describe time-varying spectral content?
I have two devices that generate different classes of signals, one simple and one complex. I would like to find a single word or short phrase that describes the increased richness in one class ...
3
votes
1answer
150 views
Limiter, compressor, AGC, dynamics processor?
What are the primary differences between the usage or definitions of the terms “AGC”, “compressor”, “limiter”, and dynamics processor? They all seem to be forms of playing with gain knobs.
2
votes
2answers
222 views
Confused in difference between sequence versus signal?
I am learning basics of signals and systems with MATLAB
If i create a vector in matlab such that
x=[ 2 5 10 20], will it be considered a sequence or a signal?
As ...
1
vote
2answers
33 views
What is the technical term for the product of “number of pixels” and “number of channel per pixel”?
Assume I have m x n pixels of an RGB image. If I calculate 3mn, what is the name of quantity for this value?
0
votes
2answers
37 views
System Response Terminology
If I have a system specified by
$$P(D)y(t)=Q(D)x(t)$$
and I specify initial conditions $y(0^-)=a, \ y'(0^-)=b,\ x(0^-)=c$ does the term $x(0^-)=c$ correspond to the zero state response or zero ...
5
votes
3answers
971 views
What is energy in image processing?
There are several web articles on the topic, but, after having read them, I still don't know what "energy" is, in the context of computer vision (CV) and image processing (IP). It is related to ...
0
votes
1answer
297 views
What is the difference between domain and range filtering?
In the context of image processing, I have heard the expressions "domain filtering" and "range filtering". What do these terms refer to? What is the difference between them?
1
vote
1answer
290 views
What is a periodic signal in image processing?
In the context of image processing (and computer vision), the concept of convolution comes up a lot. Convolution is quite related to the concept of Fourier transform and DFT. In the context of image ...
2
votes
1answer
633 views
What is the relation between time, frequency, spatial and spectral domains?
What is the relation between time, frequency, spatial and spectral domains?
I think that time and spatial domains are the "original" domains (e.g. if the signal is a greyscale image, then the domain ...
2
votes
3answers
489 views
What do we mean by spectrum?
Consider the context of image processing and computer vision, and, in particular, discrete Fourier transform.
For example, in the sentence
In the Discrete Time Fourier Transform the forward Fourier ...
3
votes
1answer
242 views
What is the difference between an impulse response and a kernel?
It seems to me they are two terms used to refer to the same concept, but, according to the Wikipedia page on Guassian filter
a Gaussian filter is a filter whose impulse response is a Gaussian ...
1
vote
2answers
111 views
Is there any opposite name for Decibel?
According to definition of decibel it’s “logarithmic unit of measurement used to express”
So in audio we often convert linear value from range 0 to 1 to logarithmic scale for example like that:
<...
-3
votes
2answers
80 views
difficulty in understanding amplitude, frequency and period
I have difficulty in understanding of some fundamental terms as amplitude. Can be there more than one amplitude for a signal? The following expression is combination of 3 sinusoidal signal, so are ...
2
votes
1answer
306 views
Quadrature demodulation, homodyne detection, lock-in detection - what's the difference?
Quadrature demodulation
Homodyne detection
Lock-in detection
What is the difference between these terms? Are they all synonomous? In my mind they kind of are, so I'm never sure which to use.
I ...
1
vote
0answers
30 views
Does Mutual information utilize spatial information to calculate image similarity?
To calculate images similarity based on Mutual Information (MI), histogram and join histogram is required. In the literature, there are 2 contradict opinions about MI operation. 1. MI does not utilize ...
1
vote
1answer
126 views
Is Oversampling a Signal Same as Discretizing the Signal?
I am confused about the new terminology 'oversampling' I have encountered very recently.
To explain it better, I am going to use numerical examples.
Now let's assume I am using a BPSK modulator and my ...
1
vote
1answer
198 views
Intuition behind cepstrum analysis terminology
In multiple books I found a parallel between spectrum-analysis terminology and cepstrum-analysis terminology that says
low pass filter $\rightarrow$ short pass lifter
I didn't read explicitly what ...
2
votes
4answers
96 views
What is the moment when all oscillators aligned to make a jump called?
Say we have a square wave and its Fourier series. When the wave doesn't jump, its oscillators aren't aligned:
But if they are aligned, the wave will jump:
What is this moment called? They might not ...
1
vote
2answers
788 views
Why is second-order Gaussian called Laplacian Gaussian?
We usually use Laplacian of Gaussian as the filter for edge detection or blob detection. But the filter itself is essentially a second order Gaussian. So why do we call it Laplacian of Gaussian? Is ...
0
votes
2answers
251 views
The precise meaning of 'coefficient' in signal processing
when I read papers on signal processing, I often see the term 'coefficient' being used to refer directly to 'samples', i.e. "We can reduce the number of coefficients, by simply subsampling the even ...
3
votes
1answer
59 views
Is there a name for the procedure of taking the FT over separate consecutive small time-blocks?
Suppose we have a continuous time-interval $I=[a,b]$, and a signal $x \colon I \to \mathbb{R}$.
A procedure that is sometimes carried out (e.g. when doing bispectral analysis) is to partition $I$ ...
4
votes
1answer
168 views
Is there a name for $f(x) = |x|^n \cdot \operatorname{sgn}(x)$?
I'm looking for a name for the following function
$$f(x) = |x|^n \cdot \operatorname{sgn}(x)$$
which is the exponent function, but with the sign stripped from the input and reattached to the output....
1
vote
2answers
637 views
When can the impulse response become zero?
The article Efficient Use Of Sparse Adaptive Filters (Proc. Asilomar Conference, Khong et al., 2006) introduces adaptive filters for the estimation of channels or systems having a sparse impulse ...
5
votes
2answers
733 views
What is the meaning of channel capacity?
If the transmitted information signal takes values from a modulation constellation, then is there a way to know what the channel capacity is?
Is there a connection between the modulation kind and ...
0
votes
1answer
191 views
What is perfect and imperfect channel?
Often in estimation of the input signal to an unknown channel, the bit error rate is plotted as the performance measure. The curve is compared with an ideal curve labelled as 'Perfect channel'. For ...
0
votes
2answers
46 views
Confusion regarding model order and lags
I have similar questions as the one asked in these posts: https://stackoverflow.com/questions/47083890/fir-filter-length-is-the-intercept-included-as-a-coefficient-matlab/47085339?noredirect=1#...
2
votes
2answers
90 views
Why use parametric based estimation methods - confusion regarding terms
Using the probability density function (pdf) we can estimate an unknown parameter using methods such as Maximum Likelihood estimation. If the pdf is not available, then Least Squares can be used. ...
2
votes
2answers
102 views
Why Is The Maximum Likelihood Estimation (MLE) Method Taken as the Benchmark for Comparing with Other Methods?
In many research articles the performance of an estimation method is compared to that of the ML estimation performance. If the performance of the method does not achieve the ML estimation performance, ...
3
votes
1answer
4k views
Difference between order and length of a filter
Let, the channel be modeled as a FIR model with order L. Mathematically, $y_n = \sum_{k=1}^L h_k u_{n-k} \tag{1}$ where $u$ is the data input to the channel and <...
1
vote
1answer
1k views
SNR for complex valued signal and when to use SNR and when to use Eb/N0?
This question is in continuation to the one asked earlier Help in understanding the formula of Signal-to-Noise-Ratio (SNR) - Part 1
Consider a model
$$y[n] = x[n] + w[n]$$
Signal means the desired ...
0
votes
1answer
213 views
What is Audio codec in simplified term?
I am trying to understand what a codec actually is
Wikipedia says
In hardware, audio codec refers to a single device that encodes analog
audio as digital signals and decodes digital back ...
