Custom image codec that renders to a WebGL canvas.

Each option has its own benefits and drawbacks.
For example, the built-in elements fit nicely among
other HTML elements, and they automatically take
advantage of browser caching, and built-in image
optimization and memory management.
They allow you to safely display images from arbitrary sources
(more on than in the CORS section below).
drawImage is great when the image must fit within
other content rendered using the <canvas> element.
You also gain control over image sizing and,
when the CORS policy allows it, read the pixels
of the image back for further processing.
Finally, WebGL gives you the highest degree of
control over the image. Not only can you read the pixels and
apply custom image algorithms, but you can also use GLSL for
hardware-acceleration.

Cross-Origin Resource Sharing (CORS)