Develop software that identifies and measures objects in an image

Note: The software does not need to be a finished mobile app at this stage, though the product/code/functionality should be portable to a mobile device at a later stage. We need someone to develop a piece of software that can measure object(s) in an image. The most likely way this would be achieved is by creating a program that: a) recognises a reference object of known dimensions AND the object to be measured; b) uses the known dimensions of the reference object in order to measure the object in question. (Note: If you have a way of doing this task without the reference object, we'd love to hear your ideas) Importantly, the product must be able to correctly identify the object to be measured in a given image as well as the reference object. Images can be sent away/uploaded for processing. OUTPUT: For the purposes of the prototype, the objects to be detected and measured should be various road signs that have been printed and cut out. The reference object should be a credit card-sized card (e.g. a business card, gift card, etc.). The reference object and the printed sign (to be measured) should be placed on a flat surface, such as a table or floor. From there, the image would be taken (or, a live feed could be used) of the two objects (reference + sign) in the same frame. From this image/live feed, the two objects will be identified and the measurement of the sign will be conducted, the results output. The measurement should be the perimeter of the sign, with the length of each side being output. Example of signs to print and use as prototype objects are attached. NB: This is a prototype, not a finished product, and thus we are looking for consistency in measurement > aesthetic merit. NB: We are aware this can be done using OpenCV, but are open to any languages being used. However, *it is important that the software be portable to a mobile app* for later stages of development. Please get in touch with any questions or clarifications. We look forward to hearing from you.