about the size of the filter

[Denybarros]

I am still confused about the size of the filter, how convolution it works ..
What do filter_h = 5 with filter_hs = [3,4,5], whetherfilter_h is the maximum length for eachfilter_hs ??
to get theimage shape, the longest maximum sentence is 56 so 56 + 2 * (5-1) = 64 .., what does it mean number 2 ?? where number 2 is obtained?