Working Fiddle Here.
在你的HTML,我只加id
您img
。
我玩了一点你的纯粹的javascript getImageBrightness
...但没有那么多。
我用“127.5”作为黑暗和光线之间的中间线。
我建议你评估它...因为人眼不像脚本那样数学。
;)
下面是脚本:
var thisImg;
function getImageBrightness(image,callback) {
var thisImgID = image.attr("id");
var img = document.createElement("img");
img.src = image.attr("src");
img.style.display = "none";
document.body.appendChild(img);
var colorSum = 0;
img.onload = function() {
// create canvas
var canvas = document.createElement("canvas");
canvas.width = this.width;
canvas.height = this.height;
var ctx = canvas.getContext("2d");
ctx.drawImage(this,0,0);
var imageData = ctx.getImageData(0,0,canvas.width,canvas.height);
var data = imageData.data;
var r,g,b,avg;
for(var x = 0, len = data.length; x < len; x+=4) {
r = data[x];
g = data[x+1];
b = data[x+2];
avg = Math.floor((r+g+b)/3);
colorSum += avg;
}
var brightness = Math.floor(colorSum/(this.width*this.height));
callback(thisImgID, brightness);
}
}
$("img").on("click", function(){
thisImg = $(this)
getImageBrightness($(this),function(thisImgID, brightness) {
document.getElementsByTagName('pre')[0].innerHTML = "Brightness: "+brightness+"<br><br>- Red border means class added -> dark,<br>- yellow border mean class added -> light";
if(brightness<127.5){
$("#"+thisImgID).addClass("dark");
}else{
$("#"+thisImgID).addClass("light");
}
});
});
CSS:
.dark{
border:3px solid red;
}
.light{
border:3px solid yellow;
}
因此,如果增加一个,并添加基于亮度变量的值的类。 – epascarello
@epascarello谢谢,我想是的,我可以尝试但不知道我能做到。 – user3699998
你认为什么很复杂?把它分解成两颗牛排。首先使用一个基本的'if/else'来获取要添加的类名。之后,它将元素名称添加到元素 – epascarello