For my project, I use canvas of fabric.js to create an label, that will be print on thermo-thing.
So I need to generate a PNG with bit-depth (color-depth) equals to 1.

I put all my elements with even black or white colors, but canvas.toDataURL( {format: “png”}) create a file with bit-depth equals to 32.

Do anyone knows how I can :

• force this bit-depth
• or modify generated image depth ?

I saw there is toBlob function, but I don’t know if I can do this transformation with it ?

(if some of my english is wrong, sorry, I tried my best)

Thank you