score:1
Accepted answer
well, my requirements changed and i no longer need to worry about this, but i will post the code i used anyways:
var imgdata = context.getimagedata(0,0,canvas.width,canvas.height);
// function to find the hex color of a specific pixel in the imgdata context.
function getpixel(imgdata, index) {
var i = index * 4, d = imgdata.data;
return rgbtohex(d[i], d[i + 1], d[i + 2])
// returns hex string of rgb values.
}
// function to caluclate offset of imgdata context and then return hex color from getpixel function call.
function getpixelfromcoordinate(imgdata, x, y) {
return getpixel(imgdata, y * imgdata.width + x);
}
// function to convert a given rgb value to a hex string.
function rgbtohex(r, g, b) {
// left shift values to allow for cheap hex construction
return "#" + ((1 << 24) + (r << 16) + (g << 8) + b).tostring(16).slice(1);
}
this code worked fine, so hopefully it will be helpful to others.
reference 1: getpixel from html canvas?
reference 2: how to use javascript or jquery to read a pixel of an image when user clicks it?
Source: stackoverflow.com
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