To give my two cents in this discussion:
First off, coming from a Computer Science background myself detection of colors, shapes, shading, and minor movement is already difficult to do. Take, for instance, this picture:
Say you wanted to run a VISR program on this and just as examples, the noodles were trees, the herbs were rocks, the Parmesan was small plants, and the tomatoes were people. First off, you would have to give the program some rules to follow like long thin lighter colored objects were trees, the white flecks were small plants, red, round objects were people and green objects were rocks. Seems simple enough right?
Certain areas of the photo would have issues with object detection, That tomato on the far left with its light reflection point could have a lot of it be confused with a tree or even small plants. The range of colors that would have to be given to each type of object to allow for full detection would have overlap. creating a whole mish-mosh of random objects which may or may not reflect the actual object you are looking at.
This in and of itself would include years of coding to get anything correct enough to use in the field. and taking into account the average starting Computer Science salary at around 70 to 90 thousand a year, fresh out of college, the people alone would raise the price of the device a whole lot. Say for instance you have one programmer work on this project, and say it took 5 years to get something that would work in the field, you are looking at a minimum of paying that one person 350 thousand for him alone to work on that project. Materials and prototyping will add to that number, and with today's tech there is no way you are gonna get that one 2 arduinos let alone 1. This program would have to be on at least a laptop with top of the line processing. It may be possible to fit the screen portion in the helmet but you would add a good 10+ pounds of gear that the person has to carry and if any of it gets damaged in any way the whole thing would shut down.
But have no fear, you can have yourself your own night vision apparatus on something as simple as a small camera, a few IR LEDs, and a viewfinder from an old VHS Camcorder that recorded everything to tapes used in VCRs (Old tech still helps) and if you want to do that, there is a video by kipkay explaining what you need and how to do it
here.
Provided it wont have edge detection and full up to date edges at that, but for around twenty bucks, it will still give you the edge in any sort of battle you go into, and with everything being contained explicitly to the helmet, there is less of a chance for it to get damaged. Oh and you can take off your helmet too.
TL;DR Edge detection is hard, Arduinos aren't enough, you will be carrying way too much, and it would be way out of the $1000 budget you set, for a while at least. stick with what you have this stuff is a good 5+ years away. Oh and if you really want night vision click the link up there ^.
Edit: I'm not trying to be mean, so please don't take it that way