I am trying to create a screen recorder for myself because my PC (Windows 10) does not have a camera for whatever reason. I know that may sound strange, but whenever I open the camera app, I get an error that says that no camera can be found. Furthermore, when any other app tries to use my camera, it still says that no camera can be found. My device manager does not even list any camera drivers or anything like that. Honestly, this is baffling to me as to how a modern PC would lack a camera. However, somehow when I play games on the Steam app, I can still use Steam's recording feature for recording videos of gameplay. I don't know if this implies that my PC actually does have a camera. Nevertheless, I am trying to create my own camera to fix my problem.
I learned about the html canvas element, and the method captureStream() that allows you to capture a video stream of the contents of the canvas. However, I've been seeing information online suggesting that this might actually require a camera, but this info has been scattered around the web and organized in confusing ways.
Can someone please clarify this for me? Does the usage of canvas.captureStream() require a camera?
Can I use HTMLCanvasElement.captureStream() if my pc doesn't have a webcam?
Yes you can.
There is no relation between this API and the webcam. You probably got confused wtih navigator.mediaDevices.getUserMedia() which also returns a MediaStream object and which indeed requires a capture device.
HTMLCanvasElement#captureStream() will produce said MediaStream from its buffer directly and thus doesn't need any capture device.
This is the same for screen-recording features, they don't need a dedicated capture device, they only do record the frames they (or the system) did generate.
By the way, for recording your screen, you'd be better using the Screen-Capture API which doesn't need a capture device either.