The getImageData() function
Summary: The getImageData() function fetches per-pixel information from the canvas
The getImageData()
function allows to retrieve an ImageData
object from your canvas. This allows you to manipulate it as
you wish and then you can add it back on to the canvas with the
putImageData()
function.
You can pass it the X/Y/W/H that you want to fetch as arguments.
Arguments to the function
- The X coordinate at which to fetching data
- The Y coordinate at which to fetching data
- The width to fetch
- The height to fetch
An example
<script>
window.onload = function ()
{
var canvas = document.getElementById('cvs');
var context = canvas.getContext('2d');
// Fetches image data from the canvas
var imgData = context.getImageData(0,0,600,250);
}
</script>