如何独立创建一个新的ImageData对象？ [英] How to create a new ImageData object independently?

问题描述

我想在代码中创建一个新的ImageData对象。如果我有一个 Uint8ClampedArray ，我想制作一个图像对象，最好的方法是什么？

I want to create a new ImageData object in code. If I have a Uint8ClampedArray out of which I want to make an image object, what is the best way to do it?

我想我可以创建一个新的canvas元素，提取它的ImageData并覆盖它的数据属性，但这似乎是一种错误的方法。

I guess I could make a new canvas element, extract its ImageData and overwrite its data attribute, but that seems like a wrong approach.

如果我可以直接使用ImageData构造函数，但我无法弄清楚如何。

It would be great if I could use the ImageData constructor directly, but I can't figure out how to.

推荐答案

这是一个有趣的问题......你不能只创建 ImageData 对象：

This is interesting problem... You can't just create ImageData object:

var test = new ImageData(); // TypeError: Illegal constructor

我也尝试过：

var imageData= context.createImageData(width, height);
imageData.data = mydata; // TypeError: Cannot assign to read only property 'data' of #<ImageData> 

但如 MDN data property is readonly。

but as described in MDN data property is readonly.

所以我认为唯一的方法是使用迭代创建对象和设置数据属性：

So I think the only way is to create object and set data property with iteration:

var canvas = document.createElement('canvas');
var imageData = canvas.getContext('2d').createImageData(width, height);
for(var i = 0; i < myData.length; i++){
    imageData.data[i] = myData[i];
}

更新：
我发现了ImageData的 data 属性中的 set 方法，因此解决方案非常简单：

Update: I have discovered the set method in data property of ImageData, so solution is very simple:

var canvas = document.createElement('canvas');
var imageData = canvas.getContext('2d').createImageData(width, height);
imageData.data.set(myData);

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