How to find the local Maxima in an analog signal in simulink? Which block is to be used to find the local Maxima ? please give the answer !!

we are doing project on audio transmission and for that in encoder there is PYSCHO ACOUSTIC MODEL -according to blocks we divided the audio into 32 sub bands in simulink using DWT block. Now, we need to find local maxima in each of these 32 sub bands seperately. Here we are getting problem as we dont know which block is to be used. We tried MIN MAX, LOCAL MAXIMA blocks but we are not getting simulation output.