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Aliasing that occurs in signals sampled in time, for instance in digital audio or the stroboscopic effect, is referred to as temporal aliasing. Aliasing in spatially sampled signals (e.g., moiré patterns in digital images ) is referred to as spatial aliasing .
The G.729.1 uses three-stage coding: embedded code-excited linear prediction (CELP) coding of the lower band, parametric coding of the higher band by Time-Domain Bandwidth Extension (TDBWE), and enhancement of the full band by a predictive transform coding algorithm called time-domain aliasing cancellation (TDAC), also known as modified ...
Recall that decimation of sampled data in one domain (time or frequency) produces overlap (sometimes known as aliasing) in the other, and vice versa. Compared to an L {\displaystyle L} -length DFT, the s N {\displaystyle s_{_{N}}} summation/overlap causes decimation in frequency, [ 1 ] : p.558 leaving only DTFT samples least affected by ...
The use of input data that extend beyond the boundaries of the logical DCT-IV causes the data to be aliased in the same way that frequencies beyond the Nyquist frequency are aliased to lower frequencies, except that this aliasing occurs in the time domain instead of the frequency domain: we cannot distinguish the contributions of a and of b R ...
The aliasing appears as a moiré pattern. The "solution" to higher sampling in the spatial domain for this case would be to move closer to the shirt, use a higher resolution sensor, or to optically blur the image before acquiring it with the sensor using an optical low-pass filter. Another example is shown here in the brick patterns.
[6] [c] It is sometimes used in derivations of the polyphase method. Fig 1: These graphs depict the spectral distributions of an oversampled function and the same function sampled at 1/3 the original rate. The bandwidth, B, in this example is just small enough that the slower sampling does not cause overlap (aliasing).
The 2D Z-transform, similar to the Z-transform, is used in multidimensional signal processing to relate a two-dimensional discrete-time signal to the complex frequency domain in which the 2D surface in 4D space that the Fourier transform lies on is known as the unit surface or unit bicircle.
Instead of using zero padding to prevent time-domain aliasing like its overlap-add counterpart, overlap-save simply discards all points of aliasing, and saves the previous data in one block to be copied into the convolution for the next block. In one dimension, the performance and storage metric differences between the two methods is minimal.