Show HN: Easily add watermarks to your images

This was my weekend (really a few hours) project. I am learning photography and occasionally want to post an image online for my friends to see. While I do this, I'd like to watermark these images with my own logo. Sometimes I post from my computer, sometimes from my phone (Pixelmator for iOS works wonderfully). Instead of having separate solutions for all this, I decided to create a simple web app that would allow me to do this. The advantage of my thing is that your watermark is saved on S3 and protected by a secret URL. No accounts to create, no passwords to remember. And the images, originals or watermarked copies are never saved.

Let me know what you think.

I'd like that if I upload a png, then get a png as the final. Sometimes jpg have artifact with graphics.

Also, the final image has no extension. That's slightly annoying in windows.

And the name of the file match the upload file. For example if I upload something.png it will be named random5876586757656758/something_watermarked.png

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