Nude pictures on early retro PCs – was it possible?

The JPEG image format was introduced in 1993 and GIF was released in 1987. Was it possible to watch nude photos on this lovely portable computer made in 1983?After publishing a review of my Compaq Portable, I got this question from a reader. The answer turned out to be not so simple as we might…

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Nude pictures on early retro PCs – was it possible?

Dmitrii Eliuseev

The JPEG image format was introduced in 1993 and GIF was released in 1987. Was it possible to watch nude photos on this lovely portable computer made in 1983?

After publishing a review of my Compaq Portable, I got this question from a reader. The answer turned out to be not so simple as we might think. Let’s figure it out.

First, let’s talk about the hardware and its possibilities — was it possible to watch any photos on the early personal computers? Obviously, the mainframes and supercomputers in the 70s were capable of processing photo images, but these computers were not available to the general public. The very first personal computer, Altair 8800, was released in 1975, a happy owner was able to enter the program using switches and to watch results using LEDs:

Altair 8800 © Wikipedia

There were even some games created for this machine, the titles like “Kill the Bit” can give the readers an idea of the gameplay itself, and there was obviously no chance to see any photo on this device.

At the end of the 70s, computers with a CP/M OS were available, this was a fully-pledged OS with a file system, disk drives, compilers, programs and games. But there was a problem — the CP/M UI was text only. In theory, it was possible using ASCII graphics, to display something like this:

A “Lenna” image in the ASCII format © https://en.wikipedia.org/wiki/Lenna

But it could be treated as a fun trick but not as a real photo. Some CP/M machines, like a Visual 1050 computer, actually had graphics capabilities, though there were no universal standards for it.

A “Visual 1050″ CP/M computer © https://www.vintagecomputing.com

One of the earliest formats available for CP/M was RLE, it encoded black and white images with a 256×192 resolution. Practically, the image may look something like this:

As we can see, it is far from perfect but still way better than a pure ASCII. A monochrome image in this format has about 6 KB size, so on a CP/M 90 KB floppy disk, up to 14 photos of this quality could be saved.

Later computers hardware became more powerful. The CGA (Color Graphics Adapter) was introduced in 1981, the MS-DOS computers were able to display graphics with up to 320×240 resolution in 4 colours. A picture of this quality may look like this:

The image size in that format is about 40 KB, so on a 360 KB floppy diskette about 8 images could be placed. Several years later, VGA adapters, introduced in 1987, were able to display 256 colour images, which were much more photorealistic:

The size of this picture is 77 KB, so 5–6 images could be saved on a 720 KB 1.44″ diskette. Later, the SVGA (Super Video Graphics Array) adapters, introduced at the end of the 80s, were able to display photorealistic images with up to 1280×1024 resolution using 16M colours, which is actually similar to what we have today.

Other computer models were also available in the 80s and 90s (Apple, Commodore, ZX Spectrum, etc), they all had the possibility to display different types of graphics. It will be too boring to enumerate them all, and I hope, readers already got the main idea about the hardware, let’s now talk about the software.

It should be more or less clear about the personal computers hardware capabilities in the early 80s, but how about the images themselves? First, let’s find an answer to a more basic question — were nude photos, in general, available at that time? The answer is “yes”. Actually, the famous Lenna image (see picture above), which is nowadays a sort of standard in the testing of image processing algorithms, was a photo scan of the Playboy magazine, made in 1973 at the University of Southern California using the scanner and the Hewlett Packard 2100 computer.

HP 2100 Computer in the 70s © https://en.wikipedia.org/wiki/HP_2100

Swedish model Lenna Sjööblom was obviously an attractive woman (the full-size image can be found here), but honestly, nobody would have remembered nowadays the old Playboy photo from 1973. Only because of this scientific publication, the “Lenna” picture became one of the most used images in computer history. Of course, this image was not scanned for any nudes sharing purposes but as an illustration for the scientific work. But anyway, the image scanning technology was available already in the 70s, and in the 80s the floppy diskettes became cheap and reliable storage for saving and copying files. This 5-1/4″ floppy disk had a 360 KB size, a MicroSD card nearby is placed for size comparison:

Thus, I suppose that in the 80s digital images were available and could be easily shared between computer users. Of course, the “adult images” were definitely a sort of rarity and image scanners were not available for the general public.

Which came first, the chicken or the egg? The image or the image format? Well, first was the image. In the simplest case, the “format” is not needed, the monochrome image is just a sequence of bits:

Thus, if we know the width and height of the image and the computer has graphics capabilities, then every developer can make a program which is displaying the picture “as is” from the binary file.

By the way, while talking about “custom” image formats, it is interesting to mention the game “Strip Poker”, released in 1985:

We can see that at the first screen the player can choose one of two personages, “Suzi” or “Melissa”, the second screen is the game itself. If we open the game files folder, it is easy to see that the data files of these two personages were just saved “as is” and there was no compression at all, all files are the same size:

 1:03 AM             71 Melissa.txt

12:18 AM 5768 Melissa1.pic

12:18 AM 5768 Melissa2.pic

12:19 AM 5768 Melissa3.pic

12:20 AM 5768 Melissa4.pic

12:21 AM 5768 Melissa5.pic

5:40 AM 35 Opn.txt

12:04 AM 5768 Opps.pic

12:59 PM 50304 Poker.exe

1:06 AM 1288 Screen.pic

12:03 AM 5768 Stitle.pic

5:09 AM 69 Suzi.txt

12:02 AM 5768 Suzi1.pic

1:33 AM 5768 Suzi2.pic

12:00 AM 5768 Suzi3.pic

12:01 AM 5768 Suzi4.pic

12:00 AM 5768 Suzi5.pic

Game developers did their best to minimize the size — each file is only 5768 bytes in size, which gives us only a 320×18 grayscale image. And indeed, we can open the pic-file using Python and see that and many details are missing:

Probably the game is using a separate background image or drawing some details (like vertical lines) programmatically, developers definitely used some tricks to effectively display 320×18 images on the 320×240 screen.

Of course, saving images “as is” can be space consuming, and developers tried to find better ways of saving the data. One of the first image encoding methods was RLE (Run-Length Encoding). In this format every block of data is stored in the “count, value“ pairs, this allows to save images more efficiently. As a simplified example, the sequence of black and white dots “BWWWWBWWWW” can be saved as “1B3W1B4W”. As we can see, it is a bit more compact and can be good for graphs or tables, but for photorealistic images, the “compressed” image can be even larger than the original.

One of the first widely used formats was PCX (PiCture eXchange), which was introduced in 1985. This format is also using the RLE encoding, and as we can see, the header fields store a lot of additional information:

// Standard PCX header (C/C++)

struct PCXHeader {

char ID; // ID, always 0x0A

char Version; // The version number

char Encoding; // Use of encoding (0, 1)

char BitPerPixel; // 1, 2, 4 or 8

short X1; // The minimum x-coordinate of the image position

short Y1; // The minimum y coordinate of the image position

short X2; // The maximum x coordinate of the image position

short Y2; // The maximum y coordinate of the image position

short HRes; // The horizontal image resolution in DPI

short VRes; // The vertical image resolution in DPI

char ClrMap[16*3]; // The EGA palette for 16-color images

char Reserved1;

char NumPlanes; // Number of color planes: 1, 3, or 4

short BPL; // The number of bytes of one color plane

short Pal_t;

char Filler[58];

} Header;

The PCX format was actually not so good for saving photo images, for example, the same “Lenna” image in a 320×240 resolution has a 35 KB size in a 16-colours format and 100 KB size in 256-colours format.

The GIF (Graphics Interchange Format) was released in 1987 and compared to PCX, it is much more advanced. GIF is using the Lempel–Ziv–Welch (LZW) algorithm for data compression, which is way more efficient — the same 320×240 image, saved in GIF format, has only 37 KB size compared to 100 KB in PCX. In 1989 the extended version of GIF was released, which is able to display animation as well. Surprisingly, animated GIFs are in use even today, the example can be seen even in this article — it is still the easiest and the cross-platform way to embed animated content to the page.

Finally, in 1992 the JPEG (made by the Joint Photographic Experts Group) format was introduced. It was using lossy compression and was specially designed for saving photo images. The algorithm is using the DCT (Discrete Cosine Transform) to save the data, the method itself was proposed in 1972 but as we can see, only 20 years later the real public demand for this technology appeared.

By the way, in the 90s the selling of erotic images became a business. From the technical perspective, it is funny to see these ads from 1994 PC Magazine:

Image Source © PC Mag Jun 1994

Nowadays an “over 2500 VGA pictures” or “Super VGA 1024x768x256 images” collection can cause only a smile but it was a sort of high tech at that time.

Let’s return to the original question — was it possible to watch nude photos on the XT machines at the beginning of the 80s? Technically, the answer is “yes”. These machines were able to display images and had floppy disk drives, which could make file sharing easy. This is how the process may look on a real Compaq Portable computer, made in 1983:

As we can see, it is not so fast and the image loading time is about 40s, but it still works.

But practically, this computer was released in 1983. And the PCX, GIF or JPEG image formats were at this moment just not introduced yet. Highly likely, some custom made image formats were available — the encoding was simple and almost every student or programmer was able to make a simple viewer of the monochrome images. Even more, image viewers were available on CP/M OS, which was in use before MS-DOS. So, I am pretty sure that some “adult images” may have been shared between PC users, for example on campuses, but I was not able to find any proof of that. I was able to find different image viewers for MS-DOS, but all of them were made later, in the 90s:

So the real answer is still open. If somebody was using the image scanning, viewing or editing software in the 80s or if somebody maybe has examples of such images, please write in comments, I will add this information to the article.

Thanks for reading. Those who are interested in more details are welcome to read a review of this Compaq Plus Portable computer. More information about using MS-DOS is published in another article.





































































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One thought on “Nude pictures on early retro PCs – was it possible?

  1. Aditya avatar

    It's funny that you treat this as a theoretical tech question rather than, say, just asking one of us ancients who was there, Gandalf, 3000 years ago.

    Yes, it was. The Commodore 128, for example, was even capable of displaying extremely short (probably 30 frames or so) hardcore porn loops in what was likely MCGA or the equivalent. I can say this without consulting manuals or spec sheets or anything but being a horny wee geek and seeing my first penetration on my neighbor and fellow adolescent nerd's little TV screen, after waiting a half hour for it to load from a floppy drive (pun intended). We felt like sophisticates at the Playboy Mansion.

    Also I think I had one monochrome low res boob pic on my Apple IIe, which I hid from my parents like a serial killer hides his special trophy room, at least until I found the box of VHS tapes with the labels torn off under my grandpa's bed. After that, green boobs at like 120×60 resolution or whatever it is wasn't very exciting anymore.

    So, yes. Yes, it definitely was. 😀