The purpose of this study is to find a stable spectral feature and illustrate the usability of this feature in compressing the original signal. The compression method is suitable for vibrotactile acceleration and not for force and velocity data. Because the power of the force and velocity signals is concentrated in a very lowfrequency range, it is difficult to distinguish whether the trend is consistent. In addition, the method based on STFT spectral characteristics can further reduce the compression ratio for long-term data compression and the application of multi-interaction points. The proposed coding and decoding scheme is based on the frequency domain. The original waveform can be reconstructed by obtaining the normalized amplitude spectrum, the maximum value of the STFT amplitude spectrum in each time window, and a small amount of the initial phase. For the surface texture of the same material, although the amount of
data increases significantly with a longer time for data collection, or with an increase in the number of collection points, the increase in data after compression remains small; that is, the compression ratio becomes smaller. This is because, regardless of how the data increases, the normalized amplitude spectrum characteristics change little, and the data increase after compression is small. Finally, although most of the surface textures of materials we encounter in daily life are approximately isotropic and homogeneous, we must discuss the applicability of the proposed solution in the case of surface anisotropy or unevenness:
• If the actual ratio of change per unit period is less than a certain critical value, the surface is still considered to be uniform and isotropic. The short-term amplitude spectrum trend of the tactile data remained similar after filtering.
