CanvasContext.getImageData

2023-06-28 02:52

Get the pixel data of the implicit area of the canvas.

Parameters

It is Object type.

Property	Type	Required	Description
x	Number	Yes	The x coordinate of left-upper corner of the image rect area that need to be get.
y	Number	Yes	The y coordinate of left-upper corner of the image rect area that need to be get.
width	Number	Yes	The width of the image rect area that need to be get.
height	Number	Yes	The height of the image rect area that need to be get.
success	Function	No	Callback function upon call success.
fail	Function	No	Callback function upon call failure.
complete	Function	No	Callback function upon call completion (to be executed upon either call success or failure).

The Success Return Value

Property	Type	Description
width	Number	The width of the image rect.
height	Number	The hight of the image rect.

Sample Code

copy

// .js
const ctx = my.createCanvasContext('awesomeCanvas')

ctx.getImageData({
  x: 0,
  y: 0,
  width: 100,
  height: 100,
  success(res) {
    console.log(res.width) // 100
    console.log(res.height) // 100
    console.log(res.data instanceof Uint8ClampedArray) // true
    console.log(res.data.length) // 100 * 100 * 4
  }
})