Show HN: piCards- Computer vision based audience polling solution for classrooms

Use of continuous feedback systems like clicker devices is proven to improve learning outcomes in classrooms and such devices are widely used in Universities. BUT such devices are costly and hence cannot be used in mid-low income setups. Also, carrying devices in bulk is a problem.

In our solution, we replace the clicker devices with normal sheets of paper with QR Code like patterns printed on them(We call the sheet — piCard). The four orientations of the sheet translate to options A, B, C and D. Each student gets one such sheet. The teacher asks a question and students rotate and lift up their sheets and show it to the teacher who has our scanning app running in his/her smartphone. The app scans all the sheets at once. Yes, you heard it right — at once! Whatever is visible in the single camera frame, gets scanned at once. The teacher gets to see the responses instantly with counts of correct and incorrect responses. These responses are synced to our analytics platform where we perform question, class, quiz, subject and student level analysis to track each individual student’s performance over time and clearly find out their strong and weak areas.

Here is a blog post related to it - https://medium.com/22bate7/picards-hello-world-3a2da6f7b885