javascript - Scale a Canvas so that the base64 toDataURL() is scaled as well -

i'm building chrome extension save screenshots of webpage. i've gotten screenshot pieced html5 canvas element.

if display image canvas.todataurl('image/jpeg', 0.8); works fine.

however, if try first scale image getting context , using this:

var context = canvas.getcontext('2d'); context.scale(.75,.75); 

and output canvas.todataurl('image/jpeg', 0.8); image same size 1 without scaling. missing? how can scale image?

if want scaled down <canvas>:

• create 2nd <canvas> width desired width , height want capture

• draw 1st <canvas> 2nd <canvas> using https://developer.mozilla.org/en-us/docs/html/canvas/tutorial/using_images#scaling (canvas valid drawimage() source)

• save 2nd <canvas>