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Update decoder.js #113

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Update decoder.js #113

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42 changes: 21 additions & 21 deletions src/decoder.js
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Original file line number Diff line number Diff line change
Expand Up @@ -23,19 +23,19 @@
*/


var Decoder={};
let Decoder={};
Decoder.rsDecoder = new ReedSolomonDecoder(GF256.QR_CODE_FIELD);

Decoder.correctErrors=function( codewordBytes, numDataCodewords)
{
var numCodewords = codewordBytes.length;
let numCodewords = codewordBytes.length;
// First read into an array of ints
var codewordsInts = new Array(numCodewords);
for (var i = 0; i < numCodewords; i++)
let codewordsInts = new Array(numCodewords);
for (let i = 0; i < numCodewords; i++)
{
codewordsInts[i] = codewordBytes[i] & 0xFF;
}
var numECCodewords = codewordBytes.length - numDataCodewords;
let numECCodewords = codewordBytes.length - numDataCodewords;
try
{
Decoder.rsDecoder.decode(codewordsInts, numECCodewords);
Expand All @@ -48,48 +48,48 @@ Decoder.correctErrors=function( codewordBytes, numDataCodewords)
}
// Copy back into array of bytes -- only need to worry about the bytes that were data
// We don't care about errors in the error-correction codewords
for (var i = 0; i < numDataCodewords; i++)
for (let i = 0; i < numDataCodewords; i++)
{
codewordBytes[i] = codewordsInts[i];
}
}

Decoder.decode=function(bits)
{
var parser = new BitMatrixParser(bits);
var version = parser.readVersion();
var ecLevel = parser.readFormatInformation().ErrorCorrectionLevel;
let parser = new BitMatrixParser(bits);
let version = parser.readVersion();
let ecLevel = parser.readFormatInformation().ErrorCorrectionLevel;

// Read codewords
var codewords = parser.readCodewords();
let codewords = parser.readCodewords();

// Separate into data blocks
var dataBlocks = DataBlock.getDataBlocks(codewords, version, ecLevel);
let dataBlocks = DataBlock.getDataBlocks(codewords, version, ecLevel);

// Count total number of data bytes
var totalBytes = 0;
for (var i = 0; i < dataBlocks.length; i++)
let totalBytes = 0;
for (let i = 0; i < dataBlocks.length; i++)
{
totalBytes += dataBlocks[i].NumDataCodewords;
}
var resultBytes = new Array(totalBytes);
var resultOffset = 0;
let resultBytes = new Array(totalBytes);
let resultOffset = 0;

// Error-correct and copy data blocks together into a stream of bytes
for (var j = 0; j < dataBlocks.length; j++)
for (let j = 0; j < dataBlocks.length; j++)
{
var dataBlock = dataBlocks[j];
var codewordBytes = dataBlock.Codewords;
var numDataCodewords = dataBlock.NumDataCodewords;
let dataBlock = dataBlocks[j];
let codewordBytes = dataBlock.Codewords;
let numDataCodewords = dataBlock.NumDataCodewords;
Decoder.correctErrors(codewordBytes, numDataCodewords);
for (var i = 0; i < numDataCodewords; i++)
for (let i = 0; i < numDataCodewords; i++)
{
resultBytes[resultOffset++] = codewordBytes[i];
}
}

// Decode the contents of that stream of bytes
var reader = new QRCodeDataBlockReader(resultBytes, version.VersionNumber, ecLevel.Bits);
let reader = new QRCodeDataBlockReader(resultBytes, version.VersionNumber, ecLevel.Bits);
return reader;
//return DecodedBitStreamParser.decode(resultBytes, version, ecLevel);
}