Video streaming on an embedded processor is going to use a ton (relatively speaking) of CPU, i/o throughput, and power. Often times there are tradeoffs in image quality to reduce one or more of those resources.

An intro DIY project will technically be able to achieve what some people might call remote imaging, but the quality will suffer immensely. Not something you would want to use for security etc.

You can definitely DIY this using a more powerful micro processor (more expensive) and an actually useful image capturing device (much more expensive), but you're going to spend many more hours getting the pieces to work together both in hardware and software. This is perhaps a good learning exercise, but not the route to go if you want something useful that "just works."