Messing With JPEGs In A Text Editor Is Fun And Glitchy

If you’re looking to edit an image, you might open it in Photoshop, GIMP, or even Paint Shop Pro if you’re stuck in 2005. But who needs it — [Patrick Gillespie] explores what can be done when editing a JPEG on a raw, textual level instead.

As the video explains, you generally can’t simply throw a JPEG into Notepad and start making changes all willy nilly. That’s because it’s very easy to wreck key pieces of the image format that are required to render it as an image. Particularly because Notepad likes to sanitize things like line endings which completely mess up the structure of the file. Instead, you’re best off using a binary editor that will only change specific bytes in the image when you tell it to. Do this, and you can glitch out an image in all kinds of fun digital ways… or ruin it completely. Your choice!

If you’d like to tinker around with this practice, [Patrick] has made a tool for just that purpose. Jump over to the website, load the image of your choice, and play with it to your heart’s content.

This practice is often referred to as “datamoshing,” which is a very cool word, or “databending,” which isn’t nearly as good. We’ve explored other file-format hacks before, too, like a single file that can be opened six different ways. Video after the break.

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Jpegli: Google’s Better JPEG And Possible Death Knell For WebP

Along with the rise of the modern World Wide Web came the introduction of the JPEG image compression standard in 1992, allowing for high-quality images to be shared without requiring the download of a many-MB bitmap file. Since then a number of JPEG replacements have come and gone – including JPEG 2000 – but now Google reckons that it can improve JPEG with Jpegli, a new encoder and decoder library that promises to be highly compatible with JPEG.

To be fair, it’s only the most recent improvement to JPEG, with JPEG XT being introduced in 2015 and JPEG XL in 2021 to mostly deafening silence, right along that other, better new image format people already forgot about: AVIF. As Google mentions in their blog post, Jpegli uses heuristics developed for JPEG XL, making it more of a JPEG XL successor (or improvement). Compared to JPEG it offers a higher compression ratio, 10+-bit support which should reduce issues like banding. Jpegli images are said to be compatible with existing JPEG decoders, much like JPEG XT and XL images.

Based on the benchmarks from 2012 by [Blobfolio] between JPEG XL, AVIF and WebP, it would seem that if Jpegli incorporates advancements from AVIF while maintaining compatibility with JPEG decoders out there, it might be a worthy replacement of AVIF and WebP, while giving JPEG a shot in the arm for the next thirty-odd years of dominating the WWW and beyond.

Your Text Needs More JPEG

We’ve all been victims of bad memes on the Internet, but they’re not all just bad jokes gone wrong. Some are simply bad as a result of being copies-of-copies, as each reposter adds another layer of compression to an already lossy image format like JPEG. Compression can certainly be a benefit in areas like images and videos, but [Michal] had a bit of a fever dream imagining this process applied to text. Rather than let the idea escape, he built the Lossifizer to add JPEG-like compression to text.

JPEG compression uses a system similar to the fast Fourier transform (FFT) called the discrete cosine transform (DCT) to reduce the amount of data in an image by essentially removing some frequency information. The data lost is often not noticeable to the human eye, at least until it gets out of hand. [Michal]’s system performs the same transform on text instead, with a slider to control the “amount of JPEG” in the output text. The code for this script uses a “perceptual” character map, clustering similarly-looking and similarly-sounding characters next to each other, resembling “leet speak” from days of yore, although at high enough compression this quickly gets out of hand.

One of the quirks that [Michal] discovered is that certain AI chat bots have a much less difficult time interpreting this JPEG-ified text than a human probably would have, which provides a bit of insight into how some of these algorithms might be functioning under the hood. For some more insight into how JPEG actually works on images, we posted about a deep dive into the image format a while back.

Parametric Press Unravels The JPEG Format

This is the first we’ve heard of Parametric Press — a digital magazine with some deep dives into a variety of subjects (such as particle physics, “big data” and such) that have interactive elements or simulations of various types embedded within each story.

The first one that sprung up in our news feed is a piece by [Omar Shehata] on the humble JPEG image format. In it, he explains the how and why of the JPEG encoding process, allowing the reader to play with the various concepts along the way, in real time, within the browser.