Number of datapoints after decimation in discrete wavelet wavelet analysis

1. What is the output of discrete wavelet transform?
2. What are coefficients in DWT?
3. What is decimated wavelet transform?
4. How do you choose a wavelet decomposition level?

What is the output of discrete wavelet transform?

The output A will then correspond to the approximation at the selected level. For example, if the selected level is 1, the output signal A will be the approximation coefficient A1, and the output D is the detail coefficient D1.

What are coefficients in DWT?

The DWT coefficients represent the degree of correlation between the analyzed signal and the wavelet function at different instances of time; therefore, DWT coefficients contain temporal information of the analyzed signal.

What is decimated wavelet transform?

Decimated is the regular wavelet transform, it works by downsampling our signal, reducing the number of coefficients. 64 coefficients may become 32, 16, and so on. Undecimated wavelet transform is the opposite, it works by upsampling our signal, augmenting the number of coefficients.

How do you choose a wavelet decomposition level?

Theoretically, the maximum decomposition level (M) can be calculated as: M = log2 (N), where N is the series length. When conducting a wavelet-based ANN model, it needs to determine the most suitable decomposition level from 1 to M.