javascript - 如何在 p5.js 中跟踪两种颜色？

Question

首先，这是我第一次在堆栈上发帖，所以我很抱歉我是一个菜鸟和糟糕的代码格式！

我的项目基于跟踪 3D 打印的刷新图标——一个橙色和一个蓝色。我希望两者都被跟踪（椭圆会显示）。我正在使用 p5.js（即使我将来想使用 openCV）。

我已经成功跟踪了橙色图标！据我了解，当我查看像素数组以识别颜色时，我还需要遍历目标数组（以便它可以容纳一种以上的颜色）。

//code that tracks the orange

var video;
var target;

// XY coordinate of closest color
var closestX = 0;
var closestY = 0;

var threshold = 25;

function setup() {
    createCanvas(640, 480);
    pixelDensity(1);
    video = createCapture(VIDEO);
    video.hide();
    noStroke();

    target = new TargetColor(color(255,127,80));
}

function draw() {
    background(0);
    image(video, 0, 0);
    video.loadPixels();

    var worldRecord = 500;


    for (var x = 0; x < video.width; x += 1){
        for (var y = 0; y < video.height; y += 1) {

            var index = (x + (y * video.width)) * 4;
            var redSource = video.pixels[index + 0];
            var greenSource = video.pixels[index + 1];
            var blueSource = video.pixels[index + 2];

            var d = dist(redSource, greenSource, blueSource, target.red,
                target.green, target.blue);


            if (d < worldRecord) {
                worldRecord = d;
                closestX = x;
                closestY = y;
            }
        }
    }

    if (worldRecord < 10) {

        //draw ellipse

        fill(target.rgb);
        strokeWeight(4);
        stroke(0);
        ellipse(closestX, closestY, 16, 16);
    }  
}  

//snippet of code that should allow multiple color tracking

//TWO - COLOR TRACKING

var video;
var target = [] // Empty array for targets so we can have more than 1
"object-colors"

var particles = [] //empty array of particles

// XY coordinate of closest color
var closestX = 0;
var closestY = 0;

var threshold = 25;

function setup() {
    createCanvas(640, 480);
    pixelDensity(1);
    video = createCapture(VIDEO);
    video.hide();
    noStroke();

    //pushing an object of type Target Color on the target array

    target.push(TargetColor(color(255,127,80)));
}

function draw() {
    background(0);
    image(video, 0, 0);
    video.loadPixels();   

    var worldRecord = 500;

    //For loop - Access each individual pixel in video by iterating 
    through array


    //for loop that allows us to loop over the contents of the array - targets


    for (var i = 0; i < target.length; i++){
        for (var x = 0; x < video.width; x += 1){
            for (var y = 0; y < video.height; y += 1) {

            var index = (x + (y * video.width)) * 4;
            var redSource = video.pixels[index + 0];
            var greenSource = video.pixels[index + 1];
            var blueSource = video.pixels[index + 2];

            var d = dist(redSource, greenSource, blueSource, target[i].red,
                target[i].green, target[i].blue);


            if (d < worldRecord) {
                worldRecord = d;
                closestX = x;
                closestY = y;
                }
            }
        }
    }

    if (worldRecord < 10) {

        //draw ellipse

        fill(target.rgb);
        strokeWeight(4);
        stroke(0);
        ellipse(closestX, closestY, 16, 16);
    } 
}


function mousePressed() {
    // Save color where the mouse is clicked in target variable
    target = new TargetColor(video.get(mouseX, mouseY));
}

function TargetColor(_color){
    this.rgb = _color;
    this.red = red(_color);
    this.green = green(_color);
    this.blue = blue(_color);
}

我已将目标的 for 循环放在嵌套循环中的几个不同位置，但我仍然无法弄清楚。我得到的结果是黑屏显示“未捕获类型错误：无法读取未定义的属性“红色”。

但是，它不是已经定义了吗？我错过了什么？

我将非常感谢任何提示和前进的方法！

标签： javascriptwebcamp5.js