Nowadays, time stamping images is extremely hard due to advancements in image editing. Thus, by generating time-sensitive QR codes to attach to an image and storing the hash of that in blockchain, we can securely timestamp a photo to prove it was taken on or after a certain time.
What it does
Essentially, it is an easy and secure way to timestamp photos which prevents modifying timestamps.
How we built it
First, our web service generates a QR code that can be attached to a user's photo. Then, that image with the QR code is hashed and uploaded in a transaction to Algorand. Then, when a user wants to verify the timestamp of their photo, all they have to do is upload their photo back to our service, the QR code gets scanned, and a request is made to the blockchain with the hash to prove the time it was taken.
Challenges we ran into
We ran into some challenges with setting up the service and making it visually appealing.
Accomplishments that we're proud of
We are proud of the fact that we were able to create a working model that allows users to upload images, generate QR codes as well as uploading hashes to the blockchain.
What we learned
We learned a lot about being able to generate and detect QR codes as well as more about blockchain.
What's next for chain-stamps
Some of our next steps are to consider how this can apply to videos and more content formats.