Three hidden photographs found in Mac SE ROM

The folks at the NYC Resistor hackerspace found a Macintosh SE that had been abandoned on a Brooklyn sidewalk and decided to conduct a little "digital archeology."

While digging through dumps generated from the Apple Mac SE ROM images we noticed that there was a large amount of non-code, non-audio data. Adam Mayer tested different stride widths and found that at 67 bytes (536 pixels across) there appeared to be some sort of image data that clearly was a picture of people. The rest of the image was skewed and distorted, so we knew that it wasn’t stored as an uncompressed bitmap.

After some investigation, we were able to decode the scrambled mess above and turn it into the full image with a hidden message from “Thu, Nov 20, 1986“

They say there's more curious data in the ROM that they haven't been able to decipher yet.

Ghosts in the ROM (Via Matt Richardson)


    1. And I hope they’ll be found again in the 2090’s, and the 3090’s, etc… For me, the trip is that there is stuff like like this “hidden” inside microscopic places, in digital form. A lot of this history vanishes almost as soon as it is made, or it is at least locked away in places that are nearly inaccessible. But sometimes it resurfaces from those hidden places, due to the work of interested individuals in _our_ time – and that is what I find fascinating.

      I mean, the photo that was decoded could hardly be considered interesting, except as a relic, but the more time that passes between the recording of the event, and the obfuscation of the event, and the discovery of the event, then the more interesting the result is.

      Here’s to hoping that future generations are able to keep rediscovering these digital relics.

      1. “I mean, the photo that was decoded could hardly be considered interesting, except as a relic”

        Well, I’m pretty sure the guy on the bottom right is in witness protection or something (hence the shades), so I bet this photo re-appearing is interesting to him!

    2. When the Arecibo message is decoded I bet some hipster alien is going to be all “I bet Earthlings already know what this is.”

  1. Do any of you Photoshop whizzes care to grab the images from the linked article and run them through a filter to convert them from dithered B&W back to greyscale? They’d be a lot easier to view up close.

      1. No, but there are definitely things that you can do to make them more pleasing to the human eye, aiding shape recognition. This is after scaling the image up 5 times, some blurring, smart sharpening, unsharp mask etc:

        1. Enhance 224 to 176. Enhance, stop. Move in, stop. Pull out, track right, stop. Center in, pull back. Stop. Track 45 right. Stop. Center and stop. Enhance 34 to 36. Pan right and pull back. Stop. Enhance 34 to 46. Pull back. Wait a minute, go right, stop. Enhance 57 to 19. Track 45 left. Stop. Enhance 15 to 23. Give me a hard copy right there.

        2. Nice edit, and that does work to pull a grey form out of a screened image.

          It should be noted that you still haven’t put information back that wasn’t there. The rule still stands. What you’ve done instead is to allow the program to “fill in the blanks” logically. The same effect can be achieved by simply viewing the original image at a smaller size. (Notice that in your thumbnail the two images appear equally clear.) 50% scale would probably be enough to make this image comfortable for viewing.

          Another question is if a person should edit an image for an article discussing the image being found. If the original image was produced in a dot-screen format, heavy editing such as yours misrepresents what was discovered. While people have become accustomed to being catered to with hi-def and glossy, full color images – not all images appear this way. The story above is about an image from 1986, when greyscale images for computers did not yet exist. The edit that you’ve provided may satisfy modern consumers, but it does not reflect the history of computer graphics.

          1. Absolutely agree.

            The one thing that I would add, however, is that while it does not add detail and it looks the same at a smaller resolution, it is more akin to “unpacking” the pixels. After all, the b/w dithering is nothing more than encoding grayscale into a lower resolution, in terms of color space. Blowing it up and blurring it is somewhat similar to decoding that information.

          2. Greyscale images for computers did exist in 1986, they just didn’t exist on the Macintosh. That’s why they dithered this one.

            I just wanted to see the image as a greyscale without having to get 8 feet away from it, which is what I have to do with a dithered image to get my eyes to deresolve the dots.

          3. No, there’s no new information.  There’s a good argument that information was lost.  But it is transformed into a format that is more compatible with how the human eye and brain processes images. 

            Our eyes are particularly good at preprocessing images, finding such things as edges.  The original image is all edges.  With the signal to the brain highlighting all the edges, our brains have a more difficult time doing the image recognition.  All those edges distract our brains from the faces.

            Blurring did a great job here of reducing the “noise” produced by our eyes, making faces easier to see.

          4. The Mac SE was released alongside a color machine, the Mac II, in 1987. Moreover, the Amiga (1985) and  even the Apple IIGS (1986) supported greyscale imagery. It might have been limited to 16 or 32 hues, but it was an improvement over monochrome. The resolution was somewhat limited, though

          5. Hi David, 

            The main reason I disagree with altering the image is that the original image would have been 1-bit black and white, not greyscale. Thanks for being understanding about that.

            As to it being similar to “unpacking” pixels:  
            You’re not simply uploading and decoding information. In “packed” images, the information is written into the code behind the display. The intended data exists. In your work, the program is using a filter to make a best guess when you blur it by identifying the colors of surrounding pixels through the program’s algorithm. Then when you next sharpen, you’re using that guessed information to create new boundaries. When you next use unsharp mask, it becomes even clearer that guesses are being made setting strong new edges. After all, if you’d simply blurred the image, those sunglasses, pearls, and white sweater shoulder wouldn’t have strong outlines. You’re not “unpacking” any more than I am. 

            You made conscious, selective choices about where the edges belonged, and how strong they should be. That’s not a bad thing if you’re reconstructing a damaged photo. 

            In this case, the image was as complete as it ever could be. It contained no hidden information for you to retrieve. What you did was make a wholly new image. It’s probably closer to the source image used to make the image for the SE (except that photo may have been full color) but it’s not the image found on the SE.


            My apologies to those who pointed out that other Macs DID, in fact, have greyscale (and yes, even color) in ’86 (I was really freaking tired this a.m., completely miswrote what I intended, and do sincerely apologize.) What I can now confirm – that you all conveniently left off – is that Apple Mac SE did not have grey scale capabilities, and only had a monochrome display. My reasoning still stands. The computer being represented by the image would not have been available in a greyscale format. Providing an image from that computer in grayscale misrepresents its standard capabilities, and thus, misrepresents history.

      2. I never said to put back information that wasn’t there. I realize that the number of greyscale pixels will be much lower than the number of B&W pixels. Heck, I was manipulating pixels before you were out of diapers.

        1. You were manipulating pixels in 1971? I’m impressed! I had no idea I was replying to one of the original Xerox PARC researchers.

          With credentials like yours, you sure don’t need any Photoshop whizzes to tell you anything. Sorry for the lighthearted comment and comic!

          1. Thank you. Now get off my lawn!

            But seriously, around 1980 I was building greyscale image processing systems for optics testing using Z80s and wire-wrapped graphics boards. Stuff that you couldn’t buy off the shelf.

        1. You’re right… in the original source forum, the guy who put the photos in the ROM said he added himself in since he was not present at the time they were taken.

  2. Heh…Heh…

    This was taken during an after-hours weekend party at Apple. 

    Most of the peeps in the portrait are the Janitorial staff, most were programmers, hackers and whatnot who took the job just to get their foot in the door. 

    Except for the staff accountant – she’s most likely the woman wearing pearls, back-row, third from the right – and the head custodian, Gino (not pictured.)

    Gino knew what he was doing, because he had been a custodian for 30 years b4 he was hired at Apple.

    Only the person who embedded the photo (& peeps) knows whom he or she is. But I think we all can guess why he, she or they did it.

    1. Forgot to attach sample visual interpretation of the direction the party took after the portrait was taken.

  3. The first Mac I personally owned (not used) was an SE.  It was stolen in 1992 by a burglar.  Even worse, he also took my back-up external hard drive and most of my floppy disks.  Yes, I lost everything and some can never be replaced.  I hoped he would sell it to someone who would locate me via my files and at least offer to return my data.  There was nothing as cryptic as this, though.

  4. I did a little with this with Gimp 2.8 with which I am far from expert.  I could have done more if I masked off the background and did a blur or a total background replacement to improve the over-all look.  But I have other commitments, and limited skills with this sort of enhancement.  I better results could surely be had by someone with more time and more accomplished than I am.

  5. More information about the image, other images also contained in the ROM, and how to display them can be found here:

  6. Ignoring all of the squabbling about compression and photoshop and how this was revealed year ago…haters are gonna hate. I had never heard of this before, so it’s brand new to me and I think it’s totally bad-ass!

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