I wrote a browser based app for resizing photographs

Try it out for yourself

Introduction

Years ago, I wrote a program for Windows that resizes images to make it faster and easier to upload hundreds of event photographs to social media. The problem is that it is restricted to Windows, and it is difficult to distribute Windows programs securely. To address these limitations, I decided to write a browser based version that could be accessed by anyone who uses a browser. To address security concerns, I designed it so all the image processing takes place inside the browser. Your photographs are not uploaded to a server, and they stay on your device until you decide to post them or share them via email or hard-copy. I called the application “Multiple Image Resizer” or “MRI” for short.

Accessing the MRI app

Here is the URL to MRI. And here is a QR code for mobile devices.

Using the MRI app

When you open the MRI app you will see this dialog screen.

I suggest you click the Help button to learn how to use the app.
After clicking the “Choose Files” button, and selecting some files, your browser window might look like this:

If you move the cursor off the dialog, the dialog becomes semi-transparent so you can discern the thumbnails hidden behind it. If you want to change the size of the thumbnails, enter a new Thumbnail Width (px). After increasing it to 240px, the browser window might look like this:

The most important choice is specifying the new size for your images. If your images are mostly landscape images then you would set a new width. Otherwise, you would set a new height. If you specify “No Change” then the original image sizes will be retained. You would do this if you want to convert between file types. For example, I used this capability to convert 1614 files from JPG to WEBP. This reduced the server space used by these images from 802mb to 239mb, a huge saving.

Once you have filled out the other fields and chosen a file type, you can click the Resize images button. After a few seconds, depending on the number of files and the sizes, your browser will ask you if you want to save a zip file. On Windows, the dialog looks like this:

If I save the zip file and open one of the images inside it, I will see the resized image. Because I checked the file name and copyright boxes, these items were added to the bottom of the image.

Behind the scenes

The app is written in JavaScript, CSS and HTML. It uses an external library to zip files. X’s Grok was a helpful coding assistant. There is no server code involved. In this example, MRI resized 139 images in 20.81 seconds.