Questions tagged [quantization]
Quantization, in mathematics and digital signal processing, is the process of mapping input values from a large set (often a continuous set) to output values in a (countable) smaller set, often with a finite number of elements. Rounding and truncation are typical examples of quantization processes.
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Analog to digital conversion using Python
I'm a beginner. I try emulate analog signal conversion to digital (including sampling by time and quantizing by level) using Python. Here is my code:
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Filter output quantization - does this limit effective coefficient quantization?
I am implementing a filter in hardware, and the intended maximum data input is 16-bit. The question is, if the output is to be re-quantized to 16-bit, does this mean certain coefficients are ...
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Help using vector quantization
I have a sample signal, and I computed MFCC using this code.Now I have an array of 1225x12 size, where there are 12 coefficients for 1225 frames. Now I want to test another signal against this sample, ...
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Are time series data always contain noise?
I wonder if every time series data should contain noise or not. For example I am taking the price of a ticker, say Yahoo, every hour and noting the values. Does this data contains noise or not?
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Quantization SNR of bipolar signal
I want to estimate the SNR of a bipolar signal. I know that each bit increases the SNR at 6 dB. Do i have to subtract one bit for sign, so that for bipolar signals the SNR is (n-1) x 6 dB ?
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How does delta modulation work practically?
How does delta modulation work in practice? And where is it used? I find it confusing that, in 1-bit quantization we use only 2 level; if we apply this quantization, there will be loss in information. ...
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Dealing with quantization level limiting dsp
There is a analog signal in the form as below:
$$ f(t)=A \sin(\omega(t) t+\phi)+B \sin(\omega(t-t_1) t+\phi_1) $$
Where $$B<<A$$
We are going to calculate $\phi, \phi_1, t_1 $,using dsp. But ...
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Cannot understand the attenuation in signal as the audio bit depth of adc changes
I am working on Active Noise Cancellation Project. I came across this strange problem, where the signal is getting attenuated as the audio bit depth changes and I cannot understand it!
My circutit :I ...
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Uniform quantizer for gaussian input signal
I have a gaussian signal $x$ with zero mean and unit variance. I am quantizing it by using a uniform quantizer of step size $q$ calculated by
$$q = \frac{x_\mathrm{max} - x_\mathrm{min}}{2^{M_\mathrm{...
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What is "hard quantization" strategy?
I am working on classification and several times I encountered with this term.
What is hard quantization strategy?
What does it differ from soft approach?
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Why are vector quantizers not used in video codecs?
Using a vector quantizer (VQ), groups of image samples (or motion compensated and/or transformed data) can be quantized as vectors. I'm curious about why VQs are not preferred in the modern, highly ...
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ensure stability against coefficient quantization
for a filter:
$$ H(z)=\frac{1+0.1z^{-1}}{1+0.1z^{-1}+0.9998z^{-2}} $$
Which precautions could be taken to ensure that the filter does not become unstable because of coefficient quantization? I've ...
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Quantization Image using MATLAB
I'm trying to quantize an image 8 bits to 4 or 2-bits uniformly. I searched internet, interestingly I could not find what I want exactly. Then I wrote an simple code for it myself. I'm curious about ...
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Sampling Rate Effect on Quantizer SNR
I am currently reading the 'Coding' chapter on Rabiner & Schafer's Book on speech processing.
In one of its exercises, the reader is given a simple A/D converter using 16-bit uniform ...
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From a physics perspective, why does D/A quantization error result in a noise floor?
For the last week or so I have been trying to understand how quantization error results in the noise floor outside of a mathematical perspective and I haven't really had any luck finding a source that ...
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Quantizing a filtered signal
In the process of trying to learn dialup, I've managed to learn/figure out everything except how to convert a demodulated/filtered signal back into the original data.
Here I have a random two-bit ...
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Is it theoretically possible to perfectly quantize a continuous signal?
So, I'm completely new to digital signal processing, but while reading a piece this morning about quantization it got me daydreaming: could a machine ever be fast enough to sample the position and ...
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A/D converter quantization noise
I read that in A/D converter we usually use rounding or two's complement truncation and not the sign magnitude or 1's complement truncation as in this case the quantization error is correlated to the ...
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What is "Maximum Quantization Error"?
I have an formula for this "Maximum Quantization Error" but i dont know what it is based in. Its just thrown in my study material without further explanation.
It is defined as:
$$Q = \dfrac {\Delta ...
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Audio signal dither and noise shaping
I'm trying to get a handle on the importance of the error feedback term in noise shaping operation in typical audio dither algorithms.
I'm thinking in terms of four signals. The original signal, the ...
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How to Prevent overflow/saturation in fixed point implementation of Fast Data Projection Algorithm
I am trying to implement an algorithm in real-time on a Fixed point DSP (The Blackfin from Analog Devices). The algorithm does a lot of stuff, but in the middle it performs an algorithm called "Fast ...
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In image compression using transforms, how to deal with the transformed coefficients as they are not integers?
I am new to the field of image compression. While going through various texts, I read about how transforming the image to another domain using, for example, the wavelet transform, or the DCT, makes it ...
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