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/*
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.
*/
var GridSampler = {};
GridSampler.checkAndNudgePoints=function( image, points)
{
var width = qrcode.width;
var height = qrcode.height;
// Check and nudge points from start until we see some that are OK:
var nudged = true;
for (var offset = 0; offset < points.length && nudged; offset += 2)
{
var x = Math.floor (points[offset]);
var y = Math.floor( points[offset + 1]);
if (x < - 1 || x > width || y < - 1 || y > height)
{
throw "Error.checkAndNudgePoints ";
}
nudged = false;
if (x == - 1)
{
points[offset] = 0.0;
nudged = true;
}
else if (x == width)
{
points[offset] = width - 1;
nudged = true;
}
if (y == - 1)
{
points[offset + 1] = 0.0;
nudged = true;
}
else if (y == height)
{
points[offset + 1] = height - 1;
nudged = true;
}
}
// Check and nudge points from end:
nudged = true;
for (var offset = points.length - 2; offset >= 0 && nudged; offset -= 2)
{
var x = Math.floor( points[offset]);
var y = Math.floor( points[offset + 1]);
if (x < - 1 || x > width || y < - 1 || y > height)
{
throw "Error.checkAndNudgePoints ";
}
nudged = false;
if (x == - 1)
{
points[offset] = 0.0;
nudged = true;
}
else if (x == width)
{
points[offset] = width - 1;
nudged = true;
}
if (y == - 1)
{
points[offset + 1] = 0.0;
nudged = true;
}
else if (y == height)
{
points[offset + 1] = height - 1;
nudged = true;
}
}
}
GridSampler.sampleGrid3=function( image, dimension, transform)
{
var bits = new BitMatrix(dimension);
var points = new Array(dimension << 1);
for (var y = 0; y < dimension; y++)
{
var max = points.length;
var iValue = y + 0.5;
for (var x = 0; x < max; x += 2)
{
points[x] = (x >> 1) + 0.5;
points[x + 1] = iValue;
}
transform.transformPoints1(points);
// Quick check to see if points transformed to something inside the image;
// sufficient to check the endpoints
GridSampler.checkAndNudgePoints(image, points);
try
{
for (var x = 0; x < max; x += 2)
{
//var xpoint = (Math.floor( points[x]) * 4) + (Math.floor( points[x + 1]) * qrcode.width * 4);
var bit = image[Math.floor( points[x])+ qrcode.width* Math.floor( points[x + 1])];
//qrcode.imagedata.data[xpoint] = bit?255:0;
//qrcode.imagedata.data[xpoint+1] = bit?255:0;
//qrcode.imagedata.data[xpoint+2] = 0;
//qrcode.imagedata.data[xpoint+3] = 255;
//bits[x >> 1][ y]=bit;
if(bit)
bits.set_Renamed(x >> 1, y);
}
}
catch ( aioobe)
{
// This feels wrong, but, sometimes if the finder patterns are misidentified, the resulting
// transform gets "twisted" such that it maps a straight line of points to a set of points
// whose endpoints are in bounds, but others are not. There is probably some mathematical
// way to detect this about the transformation that I don't know yet.
// This results in an ugly runtime exception despite our clever checks above -- can't have
// that. We could check each point's coordinates but that feels duplicative. We settle for
// catching and wrapping ArrayIndexOutOfBoundsException.
throw "Error.checkAndNudgePoints";
}
}
return bits;
}
GridSampler.sampleGridx=function( image, dimension, p1ToX, p1ToY, p2ToX, p2ToY, p3ToX, p3ToY, p4ToX, p4ToY, p1FromX, p1FromY, p2FromX, p2FromY, p3FromX, p3FromY, p4FromX, p4FromY)
{
var transform = PerspectiveTransform.quadrilateralToQuadrilateral(p1ToX, p1ToY, p2ToX, p2ToY, p3ToX, p3ToY, p4ToX, p4ToY, p1FromX, p1FromY, p2FromX, p2FromY, p3FromX, p3FromY, p4FromX, p4FromY);
return GridSampler.sampleGrid3(image, dimension, transform);
}