root / trunk / web / dojo / dojox / encoding / bits.js
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/*
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Copyright (c) 2004-2010, The Dojo Foundation All Rights Reserved.
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Available via Academic Free License >= 2.1 OR the modified BSD license.
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see: http://dojotoolkit.org/license for details
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*/
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if(!dojo._hasResource["dojox.encoding.bits"]){ |
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dojo._hasResource["dojox.encoding.bits"]=true; |
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dojo.provide("dojox.encoding.bits");
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dojox.encoding.bits.OutputStream=function(){ |
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this.reset();
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}; |
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dojo.extend(dojox.encoding.bits.OutputStream,{reset:function(){ |
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this.buffer=[];
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this.accumulator=0; |
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this.available=8; |
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},putBits:function(_1,_2){ |
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while(_2){
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var w=Math.min(_2,this.available); |
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var v=(w<=_2?_1>>>(_2-w):_1)<<(this.available-w); |
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this.accumulator|=v&(255>>>(8-this.available)); |
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this.available-=w;
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if(!this.available){ |
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this.buffer.push(this.accumulator); |
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this.accumulator=0; |
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this.available=8; |
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} |
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_2-=w; |
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} |
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},getWidth:function(){ |
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return this.buffer.length*8+(8-this.available); |
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},getBuffer:function(){ |
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var b=this.buffer; |
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if(this.available<8){ |
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b.push(this.accumulator&(255<<this.available)); |
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} |
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this.reset();
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return b;
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}}); |
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dojox.encoding.bits.InputStream=function(_3,_4){ |
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this.buffer=_3;
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this.width=_4;
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this.bbyte=this.bit=0; |
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}; |
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dojo.extend(dojox.encoding.bits.InputStream,{getBits:function(_5){ |
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var r=0; |
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while(_5){
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var w=Math.min(_5,8-this.bit); |
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var v=this.buffer[this.bbyte]>>>(8-this.bit-w); |
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r<<=w; |
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r|=v&~(~0<<w);
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this.bit+=w;
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if(this.bit==8){ |
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++this.bbyte;
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this.bit=0; |
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} |
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_5-=w; |
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} |
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return r;
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},getWidth:function(){ |
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return this.width-this.bbyte*8-this.bit; |
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}}); |
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} |