How can I use maximum resolution of the device when capturing a screenshot?

[gkrialashvili]

I have a problem when I want to capture the screenshot on small devices, the image gets stretched and has a horrible quality afterward. So I just want to send captured image with full resolution and quality to a post call and show smaller resolution image to user. But anything I do image looks horrible.

https://codepen.io/gkrialashvili/pen/KKxzBdg (child webcam component)

https://codepen.io/gkrialashvili/pen/RwYaBWO (Parent)