Smoothing lines in canvas:

• http://codetheory.in/html5-canvas-drawing-lines-with-smooth-edges/
• http://stackoverflow.com/questions/15601131/html5-canvas-line-how-can-i-let-them-appear-smoother

SVG has better antialiasing? This appears not to be true with you take advantage of the retina display in canvas?

for SVG check out the Rachaellibrary.

• SVG drawing example

put image on canvas: drawImage