# Box horizontal blur - hard 2-pixel average
# range -128..128
# sum of line must not exceed the range!
# horizontal coefficients
   0,   64,   64,    0
   0,   64,   64,    0
   0,   64,   64,    0
   0,   64,   64,    0
   0,   64,   64,    0
   0,   64,   64,    0
   0,   64,   64,    0
   0,   64,   64,    0
   0,   32,   64,   32
   0,    0,   64,   64
   0,    0,   64,   64
   0,    0,   64,   64
   0,    0,   64,   64
   0,    0,   64,   64
   0,    0,   64,   64
   0,    0,   64,   64