Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [resampling]

183 questions
31
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7 answers

What is an algorithm to re-sample from a variable rate to a fixed rate?

I have a sensor that reports its readings with a time stamp and a value. However, it does not generate readings at a fixed rate. I find the variable rate data difficult to deal with. Most filters expect a fixed sample rate. Drawing graphs is easier…
FigBug
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5 answers

what is better: up- or downsampling?

I want to compare two signals or curves. Unfortunately they have different sample rates. The first one is sampled at 30 Hz, the second at 2000 Hz. Matlab has the function 'resample' and I thought, this would make comparison much easier. My…
NelsonOrange
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15
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3 answers

What are the relative merits of various upsampling schemes?

I recently encountered a DSP system which did some internal upsampling via zero padding. Expecting zero-order-hold, I was surprised to find that a DC signal did not produce a DC output; many harmonics of the internal (lower) sampling frequency were…
nibot
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2
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1 answer

The condition in order to not lose information after upsampling and downsampling

If you have a signal x[n] and it is interpolated by N and then decimated by M, how do you ensure minimum distortion in x[n] from the resampling process?
Zara
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2
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2 answers

Resampling necessary?

I have a file that is composed of n data records with a sample rate s. Each of these records has a duration d. Now due to postprocessing I have to change the duration to d=d/3, thus afterwards I'll have 3*n data records stored in the file. I'm now…
Durin
1
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3 answers

Theoretical considerations for Using Finite Arrays to Represent Samples of Signals of Infinite Length

Discrete signals can come from sampling continuous-time signals. A continuous-time signal can be of infinite support. For instance, a sin wave. In terms of mathematical description of signals and systems, it is assumed that a discrete signal is a…
Ziqi Fan
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1 answer

What happens when I try to resample a speech recording from 8kHz to 16kHz?

I have a question regarding resampling in the context of speech. Given a speech recording sampled at 16kHz, downsampling to 8kHz will basically remove half of the samples (each 16000 samples become 8000). Now, I'm wondering about the inverse…
vphenix
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0
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1 answer

Help with resampling algorithm implementation

I am trying to implement the resampling algorithm as described in this paper: https://ccrma.stanford.edu/~jos/resample/resample.pdf I managed to construct the $h$ (windowed sinc) table, and I have implemented the loop. I am having a hard time to…
Marco Castorina
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0
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2 answers

Sample rate conversion of a complex bandpass signal

I have a complex bandpass signal. I need to upconvert it from 230.4 Msps to 245.75 Msps, i.e. by a factor of 16/15. What would be the best way to do it?
samir mishra
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1 answer

Does resampling to low number of samples lead to loss in high frequency content?

I am building an one dimensional Convolutional Neural Network and wish to feed it raw audio but it turns out that the number of samples is very larger. The audio was sampled at 48 kHz and the duration is 20 sec each which makes the number of samples…
InputBlackBoxOutput
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0
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1 answer

Decimating by last interpolating factor? (Multi-stage)

Let's say I have a multi-stage interpolator at the transmitter, which interpolates by 2, 4 and 8 (that is, 64). When decimating (at the receiver) why should I start decimating by 8, then 4, then 2, instead of 2, 4 and 8? I mean what's the reason…
researcher9
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0
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Delay of non-polyphase vs polyphase FIR filters

I implemented a polyphase filter function for interpolating and decimating. It works great (I compared it to what I'd get by interp/decim by inserting L-1 zeros and I get the same results) except for when I compensate delay. I mean, what I'm doing…
researcher9
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0
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Various size arrays interpolation - resampling

sorry if it's stupid question but it’s third day that I try to figure it out how to do that. And just can’t find the solution. Let’s say I have array $A$ size 4, and $B$ size 8. And I need to put/spread evenly all 8 values from $B$ to 4 places in…
pajczur
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0
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0 answers

Length of a resampled audio signal

It seems to me intuitively if I have a signal $y$ with sampling frequency $f_0$, then if I resample that signal with $f_{new}$ the correct number of samples will be $\frac{f_{new}}{f_0} \cdot len(y)$. But I'm using a library which includes an…
Nimitz14
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