▁expects ▁to ▁make ▁use ▁of ▁the ▁H AM ▁( Hold - And - Mod ify ) ▁mode ▁of ▁the ▁Am iga ▁ch ips et . ▁In ▁H AM 6 ▁format ▁the ▁colour ▁map ▁will ▁have ▁up ▁to ▁ 1 6 ▁entries , ▁but ▁the ▁image ▁will ▁have ▁ 6 ▁( or ▁possibly ▁ 5 ▁bit plan es ). ▁In ▁H AM 8 ▁format ▁the ▁colour ▁map ▁will ▁have ▁up ▁to ▁ 6 4 ▁entries ▁but ▁the ▁image ▁will ▁have ▁ 8 ▁( or ▁possibly ▁ 7 ▁bit plan es ). ▁ ▁The ▁last ▁two ▁bit plan es ▁( if ▁an ▁odd ▁number ▁of ▁bit plan es ▁assume ▁an ▁extra ▁bit plane ▁which ▁is ▁always ▁ 0 ) ▁are ▁control ▁flags ▁which ▁indicate ▁how ▁to ▁use ▁the ▁first ▁ 4 ▁( or ▁ 6 ) ▁bit plan es . ▁ ▁If ▁the ▁first ▁pixel ▁of ▁a ▁scan line ▁is ▁a ▁modification ▁pixel , ▁then ▁modify ▁and ▁use ▁the ▁image ▁border ▁colour . ▁ ▁Note ▁that ▁when ▁using ▁ 4 ▁bits ▁to ▁modify ▁a ▁colour ▁component ▁you ▁should ▁use ▁the ▁ 4 ▁bits ▁in ▁the ▁upper ▁ 4 ▁bits ▁of ▁the ▁component ▁AND ▁in ▁the ▁lower ▁ 4 ▁bits ▁( to ▁avoid ▁reducing ▁the ▁overall ▁colour ▁gam ut ). ▁When ▁using ▁ 6 ▁bits ▁this ▁is ▁less ▁important , ▁but ▁you ▁can ▁still ▁put ▁the ▁ 2 ▁most ▁significant ▁bits ▁of ▁the ▁modification ▁bits ▁into ▁the ▁least ▁significant ▁two ▁bits ▁of ▁the ▁colour ▁component . ▁ ▁P B M ▁images ▁cannot ▁exist ▁in ▁hold ▁and