Denoise in the Pool Alarm System Based on Wavelet Transform

A method operating at an outdoor swimming pool is presented in this paper. In a swimming pool, one key problem we faced is that the SNR (signal to noise ratio) will be lower than general surroundings such as bubbles, shadow, water waves, and lower contrast. In order to eliminate noise and preserve the edge and texture detail in the image that we obtained, we select the wavelet denoising algorithm. Because the contrast is lower and the wavelet transform will make the image fuzzy, firstly, we use the canny edge detection operator to detect the feature of the image. generally, water waves are in the special location for the swimming pool, we ignore the water waves edge information. Secondly, we use wavelet transform to process the processed edge image and the original image, then we add these wavelet coefficients at the corresponding level, we will reserve the first level wavelet transform coefficients. Finally, we can use the Donoho hard threshold denoise technology to eliminate the noise. For our actual situation, our algorithm makes some improvement in two aspects. The experiment shows that image denoise perform better than that using traditional method.