Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [linear-prediction]

50 questions
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Theory behind Linear Predictive Coding (LPC)

What is the theory behind LPC? Why are(were) certain implementations of LPC said to be more tolerant of transmission or encoding errors quantization than other compressed voice encoding schemes? Can LPC methods also be used for smoothing or…
hotpaw2
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Speech Compression - In LPC how does the linear predictive filter work on a general level?

Hi I'm taking a multimedia systems course and I'm preparing for my exam on tuesday. I'm trying to get my head around LPC compression on a general level, but I'm having trouble with what is going on with the linear predictive filter part. This is…
user1058210
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Is the Wiener filter operating at the Cramér–Rao bound?

I have been told (Wikipedia agrees) that the Wiener filter is optimal when signal and (additive) noise are WSS. Optimal in the sense that it minimizes the mean-square error. The Cramér–Rao bound is the lower bound on the variance of an unbiased…
fabian_pedd
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Image Interpolation Using the Yule Walker Equations

I have been studying about the Yule-Walker equations for prediction of a time series data from knowledge of past values of the series. Is there any way I can use the same in an image to exploit the correlation between image pixels in order to…
Curiosity
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Estimate Instantaneous Frequency Using LMS Algorithm

I hope someone can help me with the following problem: I want to estimate the frequency of a sound file that is composed of a sinusoidal with varying frequency and additive white noise: $$ x \left[ n \right] = \sin \left( \varTheta \left[ n…
Phobos
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Is Linear Prediction ever exact?

I'm just learning about linear prediction and was wondering whether or not there are any signals that would produce no error if run through a linear prediction algorithm. I was thinking (maybe naively) that if we have a linear signal (one that…
compscinoob
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Compression algorithms specific to complex signals

I am looking for (lossy or lossless) compression algorithms dedicated to complex signals. The latter could be composite data (like the left and right for stereo audio), a Fourier transformation or an intermediate step of a complex processing, an…
Laurent Duval
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What is the need for prediction filter in PCM and DPCM?

The DPCM works by the difference between actual samples and predicted samples. If we already have the actual samples, we can quantize it and encode it later. But why we use prediction filter? And by the definition "predicts the present samples…
Venkat Karthik
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How is cross-correlation related with orthogonality?

In linear prediction we can say that in case of optimum linear predictor the error with be orthogonal to data. And when we derive minimum mean square error for $\underline{y} = \mathbf{a}\underline{x} + \underline{b}$ case we find following…
Tab
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Pre-emphasizing in speech recognition

Usually, in speech recognition, the techniques that are used are based on the linear prediction model (Fant, 1960). Parallel to this, the human speech production mechanism causes energy to drop across frequencies resulting in less information in the…
Massinissa
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Intuitions on Kumaresan-Tufts algorithm for exponential fit

I am analyzing a transient signal presumably consisting of superposed exponentials. Such a case is indicated for the Prony analysis, but my data aren't noiseless enough, so I have turned to the Kumaresan-Tufts (KT) algorithm. After reading the…
Victor Pira
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How do I go from LPC coefficients to a filter polynomial?

I've recently begun experimenting with LPC, and while I understand that it works, I'm still slightly lost on why it works. Specifically, I understand that LPC involves finding coefficients $a_1, a_2, \ldots a_p$ such that for a signal…
Draconis
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Linear predictive model convolution

Accidentally asked this question in the general area and was told to ask here, so... I've been trying to develop a lightweight, relatively-fast-to-decode sound compression format for use in my gaming projects (perfect reproduction is not needed so I…
Ruben Nunez
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Voice sample prediction scheme

I have some telephone voice audio with occasional "blips" in the audio. The blips appear to come from an IP link buried in the PSTN (this is a conceptual explanation, so don't worry about things like packet loss concealment). When a packet is…
user2718
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Linear Predictive Coding for general signals

I have a signal that's monotonic and roughly linear and have been looking at using Linear Predictive Coding to encode information and compress my signal. I guess my first general question is if this is even possible for general signals? I also see…
compscinoob
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