[x264-devel] Request for i_slice_max_size setting explanation

[Alexander Sbitnev]

   Does setting i_slice_max_size to 1400 means NAL units can go up to 
1400 bytes in size?
I've tried 1400 and maximum NAL size i currently seen was 1391 bytes. Is 
there some constant value involved, limiting NAL size up to 
(i_slice_max_size - CONST). Or is it just a very small chances to see 
NAL units going all the way up to its maximum size?
   I am confused because there are also some words about overhead 
included during i_slice_max_size evaluation.