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var ZPDecoder = {
create: function(gbs){
};
decoder: function(ctx){
};
//table
p: new Uint32Array(256);
m: new Uint32Array(256);
up: new Uint8Array(256);
dn: new Uint8Array(256);
//machine independent ffz
ffzt: new Int8Array(256);
ffz: function(x) {
//find first zero bit
return (x>=0xff00) ? (ffzt[x&0xff]+8) : (ffzt[(x>>8)&0xff]);
};
init: function() {
var i, j;
for(i = 0; i<256; i++){
for(j = i; j&0x80; j<<=1){
this.ffzt[i] += 1;
}
}
this.delay = 25;
this.scount = 0;
this.preload();
fence = code;
if (code >= 0x8000)
fence = 0x7fff;
};
preload: function() {
while(this.scount <= 24){
if(
}
}
};
decode_sub: function(ctx, z){
// Save bit
var bit = ctx & 1;
// Avoid interval reversion
d = 0x6000 + ((z+a)>>2);
if( z > this.d)
z = this.d;
if( z > this.code) {
/* LPS branch */
z = 0x10000 - z;
this.a = this.a + z;
this.code = this.code + z;
/* LPS adaptation */
ctx = this.dn[ctx];
/* LPS renormalization */
var shift = ffz(a);
this.scount -= shift;
this.a = (a<<shift) % 65536;
code = (code<<shift) % 65536| ((buffer>>scount) & ((1<<shift)-1));
if(this.scount < 16) this.preload();
this.fence = this.code;
if(this.code >= 0x8000)
fence = 0x7fff;
return bit ^ 1;
}else {
/* MPS adaptation */
if (this.a >= this.m[ctx])
ctx = up[ctx];
/* MPS renormalization */
this.scount -= 1;
a = (unsigned short)(z<<1);
this.code = (code<<1) % 65536 | ((buffer>>scount) & 1);
if (this.scount<16) this.preload();
/* Adjust fence */
this.fence = this.code;
if (this.code >= 0x8000)
this.fence = 0x7fff;
return bit;
}
};
IWdecoder: function(){
return decode_sub_simple(0, 0x8000 = ((this.a + this.a + this.a) >> 3));
}
}
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