Abstract
For tube detection, an effective denoise method based on Hilbert-Huang Transform (HHT) is presented. At first, by using an empirical mode decomposition algorithm, a sum of Intrinsic Mode Functions (IMF) are obtained; then, the IMF coefficients in useful signal dominative layer are proceeded using soft threshold method; at last, those IMF coefficients are reconstructed. Compared with the traditional wavelet Transform, the HHT method is better to remove measurement noise.