我正在为浏览器开发增强现实应用程序，它可以检测DIN A4纸张上的QR码并在房间内投影3D对象。 到目前为止，我有一个使用ARUCO代码的工作解决方案，但对于我的应用程序，我需要一个QR代码以正确的角度投影3D对象。这也适用于ARUCO代码，但距离很近。如果标记距离很远，它对我不起作用。解决这个问题的方法是扫描QR码，因为可以在较大的实例上检测到轮廓。
我有一个使用QR码的解决方案，但代码在C ++中已经过了。 我试图将C ++程序重新编写为JavaScript。
这是一个与JavaScript中的ARUCO代码配合良好的解决方案：
var JS = http://jeromeetienne.github.io/slides/augmentedrealitywiththreejs/
这是基本文件：https://github.com/jeromeetienne/arplayerforthreejs
这是C ++中使用QR码的代码：
var C ++ = https://github.com/xingdi-eric-yuan/qr-decoder
到目前为止，我已经在JavaScript中编写了crdecoder.cpp中的代码。 我想要使用来自qrdecoder.cpp的脚本来检测QR码并获取位置，而不是ARUCO跟踪。 代码应该已经从QR码检测轮廓并将其写入“this.vecpair;”但它仍然没有用......
JS代码中解码的接口位于文件“threex.jsarucomarker.js”中，函数为“QR.Detector（）;”
这是我尚未完成的JS脚本，它混合了JS的ARUCO aruco.js代码和C ++ qrdecoder.cpp脚本的QR逻辑。
var QR = QR || {};
QR.Marker = function(id, corners){
this.id = id;
this.corners = corners;
};
QR.Detector = function(){
this.grey = new CV.Image();
this.thres = new CV.Image();
this.homography = new CV.Image();
this.binary = [];
this.cont = [];
this.vec4i = [];
this.contours = this.cont.contours = [];
};
QR.Detector.prototype.detect = function(image){
CV.grayscale(image, this.grey);
CV.adaptiveThreshold(this.grey, this.thres, 2, 7);
this.contours = CV.findContours(this.thres, this.binary);
//this.contours = this.findLimitedConturs(this.thres, 8.00, 0.2 * image.width * image.height);
// console.log(this.contours);
this.vecpair = this.getContourPair(this.contours);
console.log(this.vecpair);
// ARUCO CODE.. MAYBE NOT NECESSARY
//this.candidates = this.findCandidates(this.contours, image.width * 0.10, 0.05, 10);
//this.candidates = this.clockwiseCorners(this.candidates);
//this.candidates = this.notTooNear(this.candidates, 10);
//return this.findMarkers(this.grey, this.candidates, 49);
};
/* C++
struct FinderPattern{
Point topleft;
Point topright;
Point bottomleft;
FinderPattern(Point a, Point b, Point c) : topleft(a), topright(b), bottomleft(c) {}
};
bool compareContourAreas ( std::vector<cv::Point> contour1, std::vector<cv::Point> contour2 ) {
double i = fabs( contourArea(cv::Mat(contour1)) );
double j = fabs( contourArea(cv::Mat(contour2)) );
return ( i > j );
}
*/
QR.Detector.prototype.compareContourAreas = function(c1,c2){
var i = abs(CV.contourArea(c1));
var j = abs(CV.contourArea(c2));
console.log(i+' -- '+j);
return (i > j);
};
/* C++
Point getContourCentre(CONT& vec){
double tempx = 0.0, tempy = 0.0;
for(int i=0; i<vec.size(); i++){
tempx += vec[i].x;
tempy += vec[i].y;
}
return Point(tempx / (double)vec.size(), tempy / (double)vec.size());
}
*/
QR.Detector.prototype.getContourCentre = function(vec){
};
/* C++
bool isContourInsideContour(CONT& in, CONT& out){
for(int i = 0; i<in.size(); i++){
if(pointPolygonTest(out, in[i], false) <= 0) return false;
}
return true;
}
*/
QR.Detector.prototype.isContourInsideContour = function(c_in, c_out){
for(var i = 0; i<c_in.length; i++){
//console.log('-- '+c_out+' -- '+c_in[i]);
if(CV.pointPolygonTest(c_out, c_in[i]) == false) return false;
}
return true;
};
/* C++
vector<CONT > findLimitedConturs(Mat contour, float minPix, float maxPix){
vector<CONT > contours;
vector<Vec4i> hierarchy;
findContours(contour, contours, hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE);
cout<<"contours.size = "<<contours.size()<<endl;
int m = 0;
while(m < contours.size()){
if(contourArea(contours[m]) <= minPix){
contours.erase(contours.begin() + m);
}else if(contourArea(contours[m]) > maxPix){
contours.erase(contours.begin() + m);
}else ++ m;
}
cout<<"contours.size = "<<contours.size()<<endl;
return contours;
}
*/
QR.Detector.prototype.findLimitedConturs = function(contour, minPix, maxPix){
this.contours = this.cont.contours = [];
this.hierarchy = this.vec4i.hierarchy = [];
CV.findContours(contour, this.contours);
// console.log(this.contours);
var m = 0;
while(m < this.contours.length){
if(CV.contourArea(this.contours[m]) <= minPix){
this.contours.splice(this.contours[0] + m,1);
}else if(CV.contourArea(this.contours[m]) > maxPix){
this.contours.splice(this.contours[0] + m,1);
}else ++ m;
}
// console.log(this.contours.length);
return this.contours;
};
/*
vector<vector<CONT > > getContourPair(vector<CONT > &contours){
vector<vector<CONT > > vecpair;
vector<bool> bflag(contours.size(), false);
for(int i = 0; i<contours.size() - 1; i++){
if(bflag[i]) continue;
vector<CONT > temp;
temp.push_back(contours[i]);
for(int j = i + 1; j<contours.size(); j++){
if(isContourInsideContour(contours[j], contours[i])){
temp.push_back(contours[j]);
bflag[j] = true;
}
}
if(temp.size() > 1){
vecpair.push_back(temp);
}
}
bflag.clear();
for(int i=0; i<vecpair.size(); i++){
sort(vecpair[i].begin(), vecpair[i].end(), compareContourAreas);
}
return vecpair;
}
*/
QR.Detector.prototype.getContourPair = function(contours){
this.vecpair = this.cont.vecpair = [];
var bflag = new Array(contours.length, false); // similar to c++: vector<bool> bflag(contours.size(), false);?
for(var i = 0; i<contours.length - 1; i++){
if(bflag[i] == false){ //similar to c++: if(bflag[i]) continue; ??
var temp = this.cont.temp = [];
//console.log(contours[i]);
temp.push(contours[i]); //similar to c++: temp.push_back(contours[i]); ??
for(var j = i + 1; j<contours.length; j++){
if(this.isContourInsideContour(contours[j], contours[i])){
temp.push(contours[j]);
bflag[j] = true;
// console.log('true');
}
}
if(temp.length > 1){
this.vecpair.push(temp);
}
}
}
//console.log(this.vecpair);
bflag = [];
//console.log(this.vecpair.length);
for(i=0; i<this.vecpair.length; i++){
// sort(this.vecpair[0], this.vecpair[this.vecpair.length], compareContourAreas);
this.vecpair.sort(function(){
console.log('hier');
this.compareContourAreas(this.vecpair[i], this.vecpair[i].length);
});
// console.log(this.vecpair);
}
return this.vecpair;
};
/* C++
void eliminatePairs(vector<vector<CONT > >& vecpair, double minRatio, double maxRatio){
cout<<"maxRatio = "<<maxRatio<<endl;
int m = 0;
bool flag = false;
while(m < vecpair.size()){
flag = false;
if(vecpair[m].size() < 3){
vecpair.erase(vecpair.begin() + m);
continue;
}
for(int i=0; i<vecpair[m].size() - 1; i++){
double area1 = contourArea(vecpair[m][i]);
double area2 = contourArea(vecpair[m][i + 1]);
if(area1 / area2 < minRatio || area1 / area2 > maxRatio){
vecpair.erase(vecpair.begin() + m);
flag = true;
break;
}
}
if(!flag){
++ m;
}
}
if(vecpair.size() > 3){
eliminatePairs(vecpair, minRatio, maxRatio * 0.9);
}
}
*/
QR.Detector.prototype.eliminatePairs = function(){};
/* C++
double getDistance(Point a, Point b){
return sqrt(pow((a.x - b.x), 2) + pow((a.y - b.y), 2));
}
*/
QR.Detector.prototype.getDistance = function(){};
/* C++
FinderPattern getFinderPattern(vector<vector<CONT > > &vecpair){
Point pt1 = getContourCentre(vecpair[0][vecpair[0].size() - 1]);
Point pt2 = getContourCentre(vecpair[1][vecpair[1].size() - 1]);
Point pt3 = getContourCentre(vecpair[2][vecpair[2].size() - 1]);
double d12 = getDistance(pt1, pt2);
double d13 = getDistance(pt1, pt3);
double d23 = getDistance(pt2, pt3);
double x1, y1, x2, y2, x3, y3;
double Max = max(d12, max(d13, d23));
Point p1, p2, p3;
if(Max == d12){
p1 = pt1;
p2 = pt2;
p3 = pt3;
}else if(Max == d13){
p1 = pt1;
p2 = pt3;
p3 = pt2;
}else if(Max == d23){
p1 = pt2;
p2 = pt3;
p3 = pt1;
}
x1 = p1.x;
y1 = p1.y;
x2 = p2.x;
y2 = p2.y;
x3 = p3.x;
y3 = p3.y;
if(x1 == x2){
if(y1 > y2){
if(x3 < x1){
return FinderPattern(p3, p2, p1);
}else{
return FinderPattern(p3, p1, p2);
}
}else{
if(x3 < x1){
return FinderPattern(p3, p1, p2);
}else{
return FinderPattern(p3, p2, p1);
}
}
}else{
double newy = (y2 - y1) / (x2 - x1) * x3 + y1 - (y2 - y1) / (x2 - x1) * x1;
if(x1 > x2){
if(newy < y3){
return FinderPattern(p3, p2, p1);
}else{
return FinderPattern(p3, p1, p2);
}
}else{
if(newy < y3){
return FinderPattern(p3, p1, p2);
}else{
return FinderPattern(p3, p2, p1);
}
}
}
}
*/
QR.Detector.prototype.getFinderPattern = function(){};
这是我为探测器添加的CV功能 基本文件是https://github.com/jeromeetienne/arplayerforthreejs
上面的JavaScript项目中的“cv.js”此函数应与C ++版本类似
pointPolygonTest（）= http://docs.opencv.org/2.4/doc/tutorials/imgproc/shapedescriptors/point_polygon_test/point_polygon_test.html
contourArea（）= http://docs.opencv.org/2.4/modules/imgproc/doc/structural_analysis_and_shape_descriptors.html#double
//src: http://jsfromhell.com/math/is-point-in-poly
CV.pointPolygonTest = function(poly, pt){
for(var c = false, i = -1, l = poly.length, j = l - 1; ++i < l; j = i)
((poly[i].y <= pt.y && pt.y < poly[j].y) || (poly[j].y <= pt.y && pt.y < poly[i].y))
&& (pt.x < (poly[j].x - poly[i].x) * (pt.y - poly[i].y) / (poly[j].y - poly[i].y) + poly[i].x)
&& (c = !c);
return c;
};
//http://stackoverflow.com/questions/16285134/calculating-polygon-area
CV.contourArea = function(cont){
//console.log('cont: '+cont);
var area = 0; // Accumulates area in the loop
var j = cont.length-1; // The last vertex is the 'previous' one to the first
for (var i=0; i<cont.length; i++)
{
area = area + (cont[j].x+cont[i].x) * (cont[j].y+cont[i].y)
//area = area + (X[j]+X[i]) * (Y[j]-Y[i]);
j = i; //j is previous vertex to i
}
return area/2;
};
答案 0 :(得分：0)
使用JavaScript版本来检测QR码的轮廓
var CV = CV || {};
CV.Image = function(width, height, data){
this.width = width || 0;
this.height = height || 0;
this.data = data || [];
};
CV.grayscale = function(imageSrc, imageDst){
var src = imageSrc.data, dst = imageDst.data, len = src.length,
i = 0, j = 0;
for (; i < len; i += 4){
dst[j ++] =
(src[i] * 0.299 + src[i + 1] * 0.587 + src[i + 2] * 0.114 + 0.5) & 0xff;
}
imageDst.width = imageSrc.width;
imageDst.height = imageSrc.height;
return imageDst;
};
CV.threshold = function(imageSrc, imageDst, threshold){
var src = imageSrc.data, dst = imageDst.data,
len = src.length, tab = [], i;
for (i = 0; i < 256; ++ i){
tab[i] = i <= threshold? 0: 255;
}
for (i = 0; i < len; ++ i){
dst[i] = tab[ src[i] ];
}
imageDst.width = imageSrc.width;
imageDst.height = imageSrc.height;
return imageDst;
};
CV.adaptiveThreshold = function(imageSrc, imageDst, kernelSize, threshold){
var src = imageSrc.data, dst = imageDst.data, len = src.length, tab = [], i;
CV.stackBoxBlur(imageSrc, imageDst, kernelSize);
for (i = 0; i < 768; ++ i){
tab[i] = (i - 255 <= -threshold)? 255: 0;
}
for (i = 0; i < len; ++ i){
dst[i] = tab[ src[i] - dst[i] + 255 ];
}
imageDst.width = imageSrc.width;
imageDst.height = imageSrc.height;
return imageDst;
};
CV.otsu = function(imageSrc){
var src = imageSrc.data, len = src.length, hist = [],
threshold = 0, sum = 0, sumB = 0, wB = 0, wF = 0, max = 0,
mu, between, i;
for (i = 0; i < 256; ++ i){
hist[i] = 0;
}
for (i = 0; i < len; ++ i){
hist[ src[i] ] ++;
}
for (i = 0; i < 256; ++ i){
sum += hist[i] * i;
}
for (i = 0; i < 256; ++ i){
wB += hist[i];
if (0 !== wB){
wF = len - wB;
if (0 === wF){
break;
}
sumB += hist[i] * i;
mu = (sumB / wB) - ( (sum - sumB) / wF );
between = wB * wF * mu * mu;
if (between > max){
max = between;
threshold = i;
}
}
}
return threshold;
};
CV.stackBoxBlurMult =
[1, 171, 205, 293, 57, 373, 79, 137, 241, 27, 391, 357, 41, 19, 283, 265];
CV.stackBoxBlurShift =
[0, 9, 10, 11, 9, 12, 10, 11, 12, 9, 13, 13, 10, 9, 13, 13];
CV.BlurStack = function(){
this.color = 0;
this.next = null;
};
CV.stackBoxBlur = function(imageSrc, imageDst, kernelSize){
var src = imageSrc.data, dst = imageDst.data,
height = imageSrc.height, width = imageSrc.width,
heightMinus1 = height - 1, widthMinus1 = width - 1,
size = kernelSize + kernelSize + 1, radius = kernelSize + 1,
mult = CV.stackBoxBlurMult[kernelSize],
shift = CV.stackBoxBlurShift[kernelSize],
stack, stackStart, color, sum, pos, start, p, x, y, i;
stack = stackStart = new CV.BlurStack();
for (i = 1; i < size; ++ i){
stack = stack.next = new CV.BlurStack();
}
stack.next = stackStart;
pos = 0;
for (y = 0; y < height; ++ y){
start = pos;
color = src[pos];
sum = radius * color;
stack = stackStart;
for (i = 0; i < radius; ++ i){
stack.color = color;
stack = stack.next;
}
for (i = 1; i < radius; ++ i){
stack.color = src[pos + i];
sum += stack.color;
stack = stack.next;
}
stack = stackStart;
for (x = 0; x < width; ++ x){
dst[pos ++] = (sum * mult) >>> shift;
p = x + radius;
p = start + (p < widthMinus1? p: widthMinus1);
sum -= stack.color - src[p];
stack.color = src[p];
stack = stack.next;
}
}
for (x = 0; x < width; ++ x){
pos = x;
start = pos + width;
color = dst[pos];
sum = radius * color;
stack = stackStart;
for (i = 0; i < radius; ++ i){
stack.color = color;
stack = stack.next;
}
for (i = 1; i < radius; ++ i){
stack.color = dst[start];
sum += stack.color;
stack = stack.next;
start += width;
}
stack = stackStart;
for (y = 0; y < height; ++ y){
dst[pos] = (sum * mult) >>> shift;
p = y + radius;
p = x + ( (p < heightMinus1? p: heightMinus1) * width );
sum -= stack.color - dst[p];
stack.color = dst[p];
stack = stack.next;
pos += width;
}
}
return imageDst;
};
CV.gaussianBlur = function(imageSrc, imageDst, imageMean, kernelSize){
var kernel = CV.gaussianKernel(kernelSize);
imageDst.width = imageSrc.width;
imageDst.height = imageSrc.height;
imageMean.width = imageSrc.width;
imageMean.height = imageSrc.height;
CV.gaussianBlurFilter(imageSrc, imageMean, kernel, true);
CV.gaussianBlurFilter(imageMean, imageDst, kernel, false);
return imageDst;
};
CV.gaussianBlurFilter = function(imageSrc, imageDst, kernel, horizontal){
var src = imageSrc.data, dst = imageDst.data,
height = imageSrc.height, width = imageSrc.width,
pos = 0, limit = kernel.length >> 1,
cur, value, i, j, k;
for (i = 0; i < height; ++ i){
for (j = 0; j < width; ++ j){
value = 0.0;
for (k = -limit; k <= limit; ++ k){
if (horizontal){
cur = pos + k;
if (j + k < 0){
cur = pos;
}
else if (j + k >= width){
cur = pos;
}
}else{
cur = pos + (k * width);
if (i + k < 0){
cur = pos;
}
else if (i + k >= height){
cur = pos;
}
}
value += kernel[limit + k] * src[cur];
}
dst[pos ++] = horizontal? value: (value + 0.5) & 0xff;
}
}
return imageDst;
};
CV.gaussianKernel = function(kernelSize){
var tab =
[ [1],
[0.25, 0.5, 0.25],
[0.0625, 0.25, 0.375, 0.25, 0.0625],
[0.03125, 0.109375, 0.21875, 0.28125, 0.21875, 0.109375, 0.03125] ],
kernel = [], center, sigma, scale2X, sum, x, i;
if ( (kernelSize <= 7) && (kernelSize % 2 === 1) ){
kernel = tab[kernelSize >> 1];
}else{
center = (kernelSize - 1.0) * 0.5;
sigma = 0.8 + (0.3 * (center - 1.0) );
scale2X = -0.5 / (sigma * sigma);
sum = 0.0;
for (i = 0; i < kernelSize; ++ i){
x = i - center;
sum += kernel[i] = Math.exp(scale2X * x * x);
}
sum = 1 / sum;
for (i = 0; i < kernelSize; ++ i){
kernel[i] *= sum;
}
}
return kernel;
};
CV.findContours = function(imageSrc, binary){
var width = imageSrc.width, height = imageSrc.height, contours = [],
src, deltas, pos, pix, nbd, outer, hole, i, j;
src = CV.binaryBorder(imageSrc, binary);
deltas = CV.neighborhoodDeltas(width + 2);
pos = width + 3;
nbd = 1;
for (i = 0; i < height; ++ i, pos += 2){
for (j = 0; j < width; ++ j, ++ pos){
pix = src[pos];
if (0 !== pix){
outer = hole = false;
if (1 === pix && 0 === src[pos - 1]){
outer = true;
}
else if (pix >= 1 && 0 === src[pos + 1]){
hole = true;
}
if (outer || hole){
++ nbd;
contours.push( CV.borderFollowing(src, pos, nbd, {x: j, y: i}, hole, deltas) );
}
}
}
}
return contours;
};
CV.borderFollowing = function(src, pos, nbd, point, hole, deltas){
var contour = [], pos1, pos3, pos4, s, s_end, s_prev;
contour.hole = hole;
s = s_end = hole? 0: 4;
do{
s = (s - 1) & 7;
pos1 = pos + deltas[s];
if (src[pos1] !== 0){
break;
}
}while(s !== s_end);
if (s === s_end){
src[pos] = -nbd;
contour.push( {x: point.x, y: point.y} );
}else{
pos3 = pos;
s_prev = s ^ 4;
while(true){
s_end = s;
do{
pos4 = pos3 + deltas[++ s];
}while(src[pos4] === 0);
s &= 7;
if ( ( (s - 1) >>> 0) < (s_end >>> 0) ){
src[pos3] = -nbd;
}
else if (src[pos3] === 1){
src[pos3] = nbd;
}
contour.push( {x: point.x, y: point.y} );
s_prev = s;
point.x += CV.neighborhood[s][0];
point.y += CV.neighborhood[s][1];
if ( (pos4 === pos) && (pos3 === pos1) ){
break;
}
pos3 = pos4;
s = (s + 4) & 7;
}
}
return contour;
};
CV.neighborhood =
[ [1, 0], [1, -1], [0, -1], [-1, -1], [-1, 0], [-1, 1], [0, 1], [1, 1] ];
CV.neighborhoodDeltas = function(width){
var deltas = [], len = CV.neighborhood.length, i = 0;
for (; i < len; ++ i){
deltas[i] = CV.neighborhood[i][0] + (CV.neighborhood[i][1] * width);
}
return deltas.concat(deltas);
};
CV.approxPolyDP = function(contour, epsilon){
var slice = {start_index: 0, end_index: 0},
right_slice = {start_index: 0, end_index: 0},
poly = [], stack = [], len = contour.length,
pt, start_pt, end_pt, dist, max_dist, le_eps,
dx, dy, i, j, k;
epsilon *= epsilon;
k = 0;
for (i = 0; i < 3; ++ i){
max_dist = 0;
k = (k + right_slice.start_index) % len;
start_pt = contour[k];
if (++ k === len) {k = 0;}
for (j = 1; j < len; ++ j){
pt = contour[k];
if (++ k === len) {k = 0;}
dx = pt.x - start_pt.x;
dy = pt.y - start_pt.y;
dist = dx * dx + dy * dy;
if (dist > max_dist){
max_dist = dist;
right_slice.start_index = j;
}
}
}
if (max_dist <= epsilon){
poly.push( {x: start_pt.x, y: start_pt.y} );
}else{
slice.start_index = k;
slice.end_index = (right_slice.start_index += slice.start_index);
right_slice.start_index -= right_slice.start_index >= len? len: 0;
right_slice.end_index = slice.start_index;
if (right_slice.end_index < right_slice.start_index){
right_slice.end_index += len;
}
stack.push( {start_index: right_slice.start_index, end_index: right_slice.end_index} );
stack.push( {start_index: slice.start_index, end_index: slice.end_index} );
}
while(stack.length !== 0){
slice = stack.pop();
end_pt = contour[slice.end_index % len];
start_pt = contour[k = slice.start_index % len];
if (++ k === len) {k = 0;}
if (slice.end_index <= slice.start_index + 1){
le_eps = true;
}else{
max_dist = 0;
dx = end_pt.x - start_pt.x;
dy = end_pt.y - start_pt.y;
for (i = slice.start_index + 1; i < slice.end_index; ++ i){
pt = contour[k];
if (++ k === len) {k = 0;}
dist = Math.abs( (pt.y - start_pt.y) * dx - (pt.x - start_pt.x) * dy);
if (dist > max_dist){
max_dist = dist;
right_slice.start_index = i;
}
}
le_eps = max_dist * max_dist <= epsilon * (dx * dx + dy * dy);
}
if (le_eps){
poly.push( {x: start_pt.x, y: start_pt.y} );
}else{
right_slice.end_index = slice.end_index;
slice.end_index = right_slice.start_index;
stack.push( {start_index: right_slice.start_index, end_index: right_slice.end_index} );
stack.push( {start_index: slice.start_index, end_index: slice.end_index} );
}
}
return poly;
};
CV.warp = function(imageSrc, imageDst, contour, warpSize){
var src = imageSrc.data, dst = imageDst.data,
width = imageSrc.width, height = imageSrc.height,
pos = 0,
sx1, sx2, dx1, dx2, sy1, sy2, dy1, dy2, p1, p2, p3, p4,
m, r, s, t, u, v, w, x, y, i, j;
m = CV.getPerspectiveTransform(contour, warpSize - 1);
r = m[8];
s = m[2];
t = m[5];
for (i = 0; i < warpSize; ++ i){
r += m[7];
s += m[1];
t += m[4];
u = r;
v = s;
w = t;
for (j = 0; j < warpSize; ++ j){
u += m[6];
v += m[0];
w += m[3];
x = v / u;
y = w / u;
sx1 = x >>> 0;
sx2 = (sx1 === width - 1)? sx1: sx1 + 1;
dx1 = x - sx1;
dx2 = 1.0 - dx1;
sy1 = y >>> 0;
sy2 = (sy1 === height - 1)? sy1: sy1 + 1;
dy1 = y - sy1;
dy2 = 1.0 - dy1;
p1 = p2 = sy1 * width;
p3 = p4 = sy2 * width;
dst[pos ++] =
(dy2 * (dx2 * src[p1 + sx1] + dx1 * src[p2 + sx2]) +
dy1 * (dx2 * src[p3 + sx1] + dx1 * src[p4 + sx2]) ) & 0xff;
}
}
imageDst.width = warpSize;
imageDst.height = warpSize;
return imageDst;
};
CV.getPerspectiveTransform = function(src, size){
var rq = CV.square2quad(src);
rq[0] /= size;
rq[1] /= size;
rq[3] /= size;
rq[4] /= size;
rq[6] /= size;
rq[7] /= size;
return rq;
};
CV.square2quad = function(src){
var sq = [], px, py, dx1, dx2, dy1, dy2, den;
px = src[0].x - src[1].x + src[2].x - src[3].x;
py = src[0].y - src[1].y + src[2].y - src[3].y;
if (0 === px && 0 === py){
sq[0] = src[1].x - src[0].x;
sq[1] = src[2].x - src[1].x;
sq[2] = src[0].x;
sq[3] = src[1].y - src[0].y;
sq[4] = src[2].y - src[1].y;
sq[5] = src[0].y;
sq[6] = 0;
sq[7] = 0;
sq[8] = 1;
}else{
dx1 = src[1].x - src[2].x;
dx2 = src[3].x - src[2].x;
dy1 = src[1].y - src[2].y;
dy2 = src[3].y - src[2].y;
den = dx1 * dy2 - dx2 * dy1;
sq[6] = (px * dy2 - dx2 * py) / den;
sq[7] = (dx1 * py - px * dy1) / den;
sq[8] = 1;
sq[0] = src[1].x - src[0].x + sq[6] * src[1].x;
sq[1] = src[3].x - src[0].x + sq[7] * src[3].x;
sq[2] = src[0].x;
sq[3] = src[1].y - src[0].y + sq[6] * src[1].y;
sq[4] = src[3].y - src[0].y + sq[7] * src[3].y;
sq[5] = src[0].y;
}
return sq;
};
CV.isContourConvex = function(contour){
var orientation = 0, convex = true,
len = contour.length, i = 0, j = 0,
cur_pt, prev_pt, dxdy0, dydx0, dx0, dy0, dx, dy;
prev_pt = contour[len - 1];
cur_pt = contour[0];
dx0 = cur_pt.x - prev_pt.x;
dy0 = cur_pt.y - prev_pt.y;
for (; i < len; ++ i){
if (++ j === len) {j = 0;}
prev_pt = cur_pt;
cur_pt = contour[j];
dx = cur_pt.x - prev_pt.x;
dy = cur_pt.y - prev_pt.y;
dxdy0 = dx * dy0;
dydx0 = dy * dx0;
orientation |= dydx0 > dxdy0? 1: (dydx0 < dxdy0? 2: 3);
if (3 === orientation){
convex = false;
break;
}
dx0 = dx;
dy0 = dy;
}
return convex;
};
CV.perimeter = function(poly){
var len = poly.length, i = 0, j = len - 1,
p = 0.0, dx, dy;
for (; i < len; j = i ++){
dx = poly[i].x - poly[j].x;
dy = poly[i].y - poly[j].y;
p += Math.sqrt(dx * dx + dy * dy) ;
}
return p;
};
CV.minEdgeLength = function(poly){
var len = poly.length, i = 0, j = len - 1,
min = Infinity, d, dx, dy;
for (; i < len; j = i ++){
dx = poly[i].x - poly[j].x;
dy = poly[i].y - poly[j].y;
d = dx * dx + dy * dy;
if (d < min){
min = d;
}
}
return Math.sqrt(min);
};
CV.countNonZero = function(imageSrc, square){
var src = imageSrc.data, height = square.height, width = square.width,
pos = square.x + (square.y * imageSrc.width),
span = imageSrc.width - width,
nz = 0, i, j;
for (i = 0; i < height; ++ i){
for (j = 0; j < width; ++ j){
if ( 0 !== src[pos ++] ){
++ nz;
}
}
pos += span;
}
return nz;
};
CV.binaryBorder = function(imageSrc, dst){
var src = imageSrc.data, height = imageSrc.height, width = imageSrc.width,
posSrc = 0, posDst = 0, i, j;
for (j = -2; j < width; ++ j){
dst[posDst ++] = 0;
}
for (i = 0; i < height; ++ i){
dst[posDst ++] = 0;
for (j = 0; j < width; ++ j){
dst[posDst ++] = (0 === src[posSrc ++]? 0: 1);
}
dst[posDst ++] = 0;
}
for (j = -2; j < width; ++ j){
dst[posDst ++] = 0;
}
return dst;
};
//src: http://jsfromhell.com/math/is-point-in-poly
CV.pointPolygonTest = function(poly, pt){
for(var c = false, i = -1, l = poly.length, j = l - 1; ++i < l; j = i)
((poly[i].y <= pt.y && pt.y < poly[j].y) || (poly[j].y <= pt.y && pt.y < poly[i].y))
&& (pt.x < (poly[j].x - poly[i].x) * (pt.y - poly[i].y) / (poly[j].y - poly[i].y) + poly[i].x)
&& (c = !c);
return c;
};
//http://stackoverflow.com/questions/16285134/calculating-polygon-area
CV.contourArea = function(cont){
//console.log('cont: '+cont);
var area = 0; // Accumulates area in the loop
var j = cont.length-1; // The last vertex is the 'previous' one to the first
for (var i=0; i<cont.length; i++)
{
area = area + (cont[j].x+cont[i].x) * (cont[j].y+cont[i].y);
//area = area + (X[j]+X[i]) * (Y[j]-Y[i]);
j = i; //j is previous vertex to i
}
return area/2;
};