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html - Javascript Canvas Serialization/Deserialization?

Can you serialize/deserialize a canvas object in javascript?

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Besides the getImageData method, you can use canvas.toDataURL() to get an data-URL-encoded PNG. If you need to serialize to a string, it would save having to convert the raw data to a string manually. You could deserialize by creating an image and setting the src to the data URL, then drawing it to a canvas.

[Edited to account for asynchronous loading (suggested by olliej).]

function serialize(canvas) {
    return canvas.toDataURL();
}

function deserialize(data, canvas) {
    var img = new Image();
    img.onload = function() {
        canvas.width = img.width;
        canvas.height = img.height;
        canvas.getContext("2d").drawImage(img, 0, 0);
    };

    img.src = data;
}

If I remember correctly, some older versions of Safari, and maybe Opera didn't support toDataURL, but the more recent versions do.


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