[whatwg] Feature proposal - add method to CanvasRenderingContext2D

Philip Taylor excors+whatwg at gmail.com
Wed Mar 3 06:33:52 PST 2010

On Wed, Mar 3, 2010 at 1:08 PM, František Řezáč
<frantisek.rezac at calavera.info> wrote:
> Description
> add overload of (or add similarly called) method "createImageData" to
> interface CanvasRenderingContext2D which would take two arguments:
> - encodedImageBinaryData
> - dataMimeType
> which are rather self explanatory.
> Reason
> The reason is to be able to supply output of the future File API
> standard (http://www.w3.org/TR/FileAPI/) into canvas.

The canvas API already lets you do:

  var img = new Image();
  img.onload = function() {
    ctx.drawImage(img, 0, 0);
    // do processing on the canvas
  img.src = 'data:image/png;base64,...'; // get this string from
readAsDataURL etc

Is that sufficient for your use case?

Philip Taylor
excors at gmail.com

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