You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
95 lines
3.3 KiB
95 lines
3.3 KiB
/*
|
|
Ported to JavaScript by Lazar Laszlo 2011
|
|
|
|
lazarsoft@gmail.com, www.lazarsoft.info
|
|
|
|
*/
|
|
|
|
/*
|
|
*
|
|
* Copyright 2007 ZXing authors
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
|
|
export default function DataBlock(numDataCodewords, codewords) {
|
|
this.numDataCodewords = numDataCodewords;
|
|
this.codewords = codewords;
|
|
}
|
|
|
|
DataBlock.getDataBlocks = function(rawCodewords, version, ecLevel) {
|
|
|
|
if (rawCodewords.length != version.totalCodewords) {
|
|
throw "ArgumentException";
|
|
}
|
|
|
|
// Figure out the number and size of data blocks used by this version and
|
|
// error correction level
|
|
var ecBlocks = version.getECBlocksForLevel(ecLevel);
|
|
|
|
// First count the total number of data blocks
|
|
var totalBlocks = 0;
|
|
var ecBlockArray = ecBlocks.getECBlocks();
|
|
for (var i = 0; i < ecBlockArray.length; i++) {
|
|
totalBlocks += ecBlockArray[i].count;
|
|
}
|
|
|
|
// Now establish DataBlocks of the appropriate size and number of data codewords
|
|
var result = new Array(totalBlocks);
|
|
var numResultBlocks = 0;
|
|
for (var j = 0; j < ecBlockArray.length; j++) {
|
|
var ecBlock = ecBlockArray[j];
|
|
for (var i = 0; i < ecBlock.count; i++) {
|
|
var numDataCodewords = ecBlock.dataCodewords;
|
|
var numBlockCodewords = ecBlocks.ecCodewordsPerBlock + numDataCodewords;
|
|
result[numResultBlocks++] = new DataBlock(numDataCodewords, new Array(numBlockCodewords));
|
|
}
|
|
}
|
|
|
|
// All blocks have the same amount of data, except that the last n
|
|
// (where n may be 0) have 1 more byte. Figure out where these start.
|
|
var shorterBlocksTotalCodewords = result[0].codewords.length;
|
|
var longerBlocksStartAt = result.length - 1;
|
|
while (longerBlocksStartAt >= 0) {
|
|
var numCodewords = result[longerBlocksStartAt].codewords.length;
|
|
if (numCodewords == shorterBlocksTotalCodewords) {
|
|
break;
|
|
}
|
|
longerBlocksStartAt--;
|
|
}
|
|
longerBlocksStartAt++;
|
|
|
|
var shorterBlocksNumDataCodewords = shorterBlocksTotalCodewords - ecBlocks.ecCodewordsPerBlock;
|
|
// The last elements of result may be 1 element longer;
|
|
// first fill out as many elements as all of them have
|
|
var rawCodewordsOffset = 0;
|
|
for (var i = 0; i < shorterBlocksNumDataCodewords; i++) {
|
|
for (var j = 0; j < numResultBlocks; j++) {
|
|
result[j].codewords[i] = rawCodewords[rawCodewordsOffset++];
|
|
}
|
|
}
|
|
// Fill out the last data block in the longer ones
|
|
for (var j = longerBlocksStartAt; j < numResultBlocks; j++) {
|
|
result[j].codewords[shorterBlocksNumDataCodewords] = rawCodewords[rawCodewordsOffset++];
|
|
}
|
|
// Now add in error correction blocks
|
|
var max = result[0].codewords.length;
|
|
for (var i = shorterBlocksNumDataCodewords; i < max; i++) {
|
|
for (var j = 0; j < numResultBlocks; j++) {
|
|
var iOffset = j < longerBlocksStartAt ? i : i + 1;
|
|
result[j].codewords[iOffset] = rawCodewords[rawCodewordsOffset++];
|
|
}
|
|
}
|
|
return result;
|
|
};
|
|
|