Jan 15, 2022 - 1 min read

iPhone Timestamp Watermark Utility

iPhone Photo Watermark Utility - Timestmap Overlay

Have you ever taken a bunch of photos, perhaps to document something, and wanted to send them to a friend or post them online -- and retain or convey the order that the photos were taken in?

I had that problem and I looked around for a solution; I found a few potential solutions but most were paid apps or mediocre web-based uilities. I knew I that could write the code to solve the issue in an hour or two, and I decided I wanted to make the utility available for myself & others in the future.

Pure Client-Side Goodness: Secure, Private and Free!

Since I didn't want to have to worry about server-side processing or paying for/maintaining/securing a server, I decided to write the code as a purely client-side utility -- this solves my hosting/processing/security/upkeep concerns and it makes it fully secure & private for the user, too, since no data ever leaves the browser whatsoever.

The entire workload & processing occurs purely your local computer, via your browser -- all thanks to the latest Canvas APIs.

Try It Yourself!

What it does

Select photos you have exported from your iPhone, and likely any other camera that adds EXIF data (all mobiles & most digital cameras). The tool takes your "pending upload" file, adds an image into the DOM that directly references the image from your filesystem, and then further manipulates the DOM to leverage the Canvas API for overlaying text based on your configuration parameters.

The Exif data is extracted from your photos using the JS library ExifReader.

Future Plans & Ideas

In the future I'd like to add some additional functionality, almost all of which should be near-trivial to add -- it's likely that the first time I need any of these items I'll probably go ahead and add the functionality. Here are some of the things I'd like to get added:

  • Arbitrary image overlays
  • Resizing / thumbnail abilities
  • Settings should 'Re-Apply' to already-chosen images
  • Configurable download filename
  • Setting for 'order' to download files in
  • Web workers for image processing parallelism - browser support looks good!

In the meantime, if you're so inclined, please don't hesitate to submit a pull-request to add additional functionality or to improve the little tool. -- specifically custom image