add requirements instructions to developer notes

README.md

@@ -186,6 +186,11 @@ If you have finished all of this you may find the [Extra Task on Invisibility Us
 
 **Instructor Notes:** tested with [OpenCV](https://opencv.org) 4.5.x. (03/2022) on Durham University LDS (Debian Linux) + OpenSuSE Tumbleweed ([OpenCV](https://opencv.org) 4.5.x - 4.8.x). As an intro to the session, a suitable video to show the group and intro the use of chroma keying _"in the movies"_ is [https://www.youtube.com/watch?v=D3Cxm_HIiMU](https://www.youtube.com/watch?v=D3Cxm_HIiMU).
 
-**Developer Notes:** to add - additional versions with sliders controls for morphological operations, Hue range + any other parameters ; possible future enhancements - [multi-band blending](https://github.com/mtnzmz/MultiBandBlender-python), [exposure compensation](https://docs.opencv.org/4.x/d2/d37/classcv_1_1detail_1_1ExposureCompensator.html), [poisson image editing](https://learnopencv.com/seamless-cloning-using-opencv-python-cpp/).
+**Developer Notes:** to add - additional versions with sliders controls for morphological operations, Hue range + any other parameters ; possible future enhancements - [multi-band blending](https://github.com/mtnzmz/MultiBandBlender-python), [exposure compensation](https://docs.opencv.org/4.x/d2/d37/classcv_1_1detail_1_1ExposureCompensator.html), [poisson image editing](https://learnopencv.com/seamless-cloning-using-opencv-python-cpp/). 
+
+To setup on a new (non DU LDS) Linux system use:
+```
+python3 -m pip install -r requirements.txt
+```
 
 **Acknowledgements:** based on a prior set of exercises by [Magnus Bordewich](https://github.com/MagnusBordewich/ObjectTracking/), prior image processing teaching examples by [Toby Breckon](https://github.com/tobybreckon/python-examples-ip/) and the inspirational blog post of [Puranjay Kwatra](https://www.analyticsvidhya.com/blog/2021/07/harry-potters-invisible-cloak-using-opencv-python/).