Реферат - Реалізація ідеї арифметичного кодування
19

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Range <0T =091V;LH5 7=0G5==O 2 Top_Value + 1, B><C <0:A8<0;L=> <>6;8289 4>1CB>: T 2^16*(2^14 1), O:5 <5=H5 2^30. ;O 287=0G5==O code_value B0 range 28:>@8AB0=89 B8? long, I>1 70157?5G8B8 32-E 1VB>2C B>G=VABL 0@8D<5B8G=8E >1G8A;5=L. 7.3 025@H5==O :>4C20==O.@8 7025@H5=V ?@>F5AC :>4C20==O =5>1EV4=> ?>A;0B8 C=V:0;L=89 B5@<V=0;L=89 A8<2>; (EOF-A8<2>;), 0 ?>BV< ?>A;0B8 4>AB0B=N :V;L:VABL1VBV2 4;O 30@0=BVW B>3>, I> 70:>4>20=89 @O4>: ?>B@0?8BL 2 ?V4AC<:>289 @>1>G89 V=B5@20;. '5@57 B5, I> ?@>F54C@0 done_encoding() <>65 1CB8 2?52=5=0 , I> low i high >1<565=V 01> B0:, I>:low < First_qtr < Half ( high, 01>low < Half < Third_qtr ( high, B> 7=0G5==N B@510 ?5@540B8 01 01> 10 2V4?>2V4=>, 4;O 2840;5==O =5287=0G5=>ABV, O:0 70;8H8;0AL. "0:8< G8=>< EOF C=V:0;L=> 287=0G0TBLAO >AB0==V<8 ?5@540=8<8 1VB0<8.8. >45;V 4;O 0@8D<5B8G=>3> :>4C20==O.@>3@0<0 ?>28==0 ?@0FN20B8 7 <>45;;N, O:0 O2;OT A>1>N ?0@C ?5@5:>4CNG8E B01;8FL index_to_char [] i char_to_index [], V <0A82 =0:>?8G5=8E G0AB>B cum_freq []. > >AB0==L>3> <0A82C 28AC20NBLAO B0:V 28<>38:Aum_freq [i 1] ( cum_freq [i];V:>;8 =5 @>18BLAO A?@>10 :>4C20B8 A8<2>; V, 4;O O:>3> Aum_freq [i 1] = cum_freq [i];Aum_freq [0] ( Max_frequency./:I> FV C<>28 28:>=CNBLAO, 7=0G5==O 2 <0A82V =5 ?>28==V <0B8 72 O7:C 7 4V9A=B<8 7=0G5==O<8 =0:>?8G5=8E G0AB>B A8<2>;V2 B5:ABC. 45:>4C20==O, V :>4C20==O 1C4CBL ?@0FN20B8 :>@5:B=>, ?@8 G><C >AB0==L><C 1C45 B@510 <5=H5 <VAFO, O:I> G0AB>B8 B>G=V.(3040T<> CA?VH=5 :>4C20==O 50VV! 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