var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
function make_base(src) {
base_image = new Image();
base_image.src = src;
base_image.onload = function(){
ctx.drawImage(base_image, 0, 0);
imageLoaded(base_image);
}
}
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Slide 23 text
var img = ctx.getImageData(
0,
0,
canvas.width,
canvas.height
);
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Slide 24 text
img.height // number
img.width // number
img.data // Uint8ClampedArray
r g b a r g b a
[65, 113, 130, 255, 65, 113, 130, 255, ...
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Slide 25 text
No content
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Slide 26 text
Compressing
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Slide 27 text
var red = [];
var green = [];
var blue = [];
var alpha = [];
for (var i = 4; i < imgData.data.length; i+=4) {
red.push(imgData.data[i])
green.push(imgData.data[i+1])
blue.push(imgData.data[i+2])
alpha.push(imgData.data[i+3])
}