New answers tagged digital-filters
1
I did not read carefully through the whole question as I don't have time now, but have you tried some form of robust peak detection? See e.g., https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.find_peaks.html
Then you can set parameters such as the minimum (and maximum) distance, the prominence, the minimal height. If you look for minima ...
1
ARM provides efficient reference implementations of different DSP processes, including IIR:
https://arm-software.github.io/CMSIS_5/DSP/html/index.html
You can try them out and evaluate which is best for your purposes by checking performance and memory consumption. You could probably optimize for your specific application, but I wouldn’t bother unless it ...
1
Here are 3 points that you must consider :
1 - What is the minimal latency you can tolerate? This is important, as it's important to know whether to need process every sample as fast as possible or if you can perform batch processing which is typically more efficient but creates latency .
2 - No matter if you implement the IIR in fixed-point or floating-...
0
Okay, according to the wikipedia article you cited (with an appropriate substitution in notation):
$$ \Big|H(j2\pi f)\Big|^2= 10^{\frac{2.00}{10}} \times \frac{12194^4\cdot f^8}{\big(f^2+20.6^2 \big)^2(f^2+107.7^2)(f^2+737.9^2)\big(f^2+12194^2\big)^2}$$
and the dB amplitude curve is this:
$$A(f)=10\log_{10}\left(\Big|H(j2\pi f)\Big|^2\right) $$
I hope ...
3
First of all, it's not correct to say "poles should (always) be inside the unit circle for an LTI system to be stable" ; unless it's implied that system is also causal. Otherwise, if the system is noncausal, then its poles should be outside of unit circle for the system being stable.
For IIR systems that are described by LCCDEs causality must be externally ...
0
From the difference equation alone you cannot tell if a system is causal or not. For example, the difference equation
$$y[n]=-a_1y[n-1]-a_2y[n-2]+b_0x[n]\tag{1}$$
can be used to describe three different systems. The first one is a causal system, as suggested by the form given in $(1)$.
However, rewriting $(1)$ as
$$y[n-2]=-\frac{a_1}{a_2}y[n-1]-\frac{1}{...
0
Substitute $m = n+K$, i.e., $n=m-K$. This gives $$y[m-K] = -a_1 y[m-K+1] - \ldots - a_{K-1} y[m-1] - a_K y[m] + b_0 x[m-K] + b_1 x[m-K-1] + \ldots+ b_L x[m-K-L].$$ Rearranging gives $$ y[m] = -\frac{a_{K-1}}{a_K} y[m-1] - \frac{a_{K-2}}{a_K} y[m-2]-\ldots-\frac{a_1}{a_K}y[m-K+1] - \frac{1}{a_K}y[m-K] + \frac{b_0}{a_K}x[m-K] + \ldots + \frac{b_L}{a_K}x[m-K-L]....
-1
what you are describing is equivalent to a man-in-the-middle network attack.
https://en.m.wikipedia.org/wiki/Man-in-the-middle_attack
.
If the original file was watermarked, that would offer the possibility of some authentication.
Unless the individual who edited the file was inept, I don’t believe that you can in general detect the difference.
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