1function QRBitBuffer() { 2 this.buffer = []; 3 this.length = 0; 4} 5 6QRBitBuffer.prototype = { 7 8 get : function(index) { 9 var bufIndex = Math.floor(index / 8); 10 return ( (this.buffer[bufIndex] >>> (7 - index % 8) ) & 1) == 1; 11 }, 12 13 put : function(num, length) { 14 for (var i = 0; i < length; i++) { 15 this.putBit( ( (num >>> (length - i - 1) ) & 1) == 1); 16 } 17 }, 18 19 getLengthInBits : function() { 20 return this.length; 21 }, 22 23 putBit : function(bit) { 24 25 var bufIndex = Math.floor(this.length / 8); 26 if (this.buffer.length <= bufIndex) { 27 this.buffer.push(0); 28 } 29 30 if (bit) { 31 this.buffer[bufIndex] |= (0x80 >>> (this.length % 8) ); 32 } 33 34 this.length++; 35 } 36}; 37 38module.exports = QRBitBuffer; 39