Photoshop 1.0.1 source code released to public

The Computer History Museum has released the source code for the 1.0.1 version of Photoshop, making the iconic photo editing software free and legal to download.

A staple of touchup artists and graphic designers everywhere, Adobe, the software’s maker has been in some murky water recently, notably over the high pricing in Australia. The release of this early build of Photoshop should go some way towards repairing the bad rep. The museum announced the release of the code on its website.

The splash screen of the first version of Photoshop

The splash screen of the first version of Photoshop


However, it must be noted that the 1.0.1 version lacks many of the features we take for granted with the more modern versions of the software. For its time – it was first released back in 1990 – it was a very powerful photo editing utility and was exclusively a Macintosh application

The code follows the typical Mac coding tools of the time and is a mixture of Pascal and the Motorola 68000 assembly language, with the rest of the code composed of data files.

The Computer History Museum said on its blog, “With the permission of Adobe Systems Inc., the Computer History Museum is pleased to make available, for non-commercial use, the source code to the 1990 version 1.0.1 of Photoshop. All the code is here with the exception of the MacApp applications library that was licensed from Apple. There are 179 files in the zipped folder, comprising about 128,000 lines of mostly uncommented but well-structured code. By line count, about 75% of the code is in Pascal, about 15% is in 68000 assembler language, and the rest is data of various sorts.

The main workspace of Photoshop 1.0.1

The main workspace of Photoshop 1.0.1


Amazingly, nearly 130,000 lines of code for the programme were written primarily by Photoshop co-founder Thomas Knoll, who was the lone engineer for the first version. Adobe only added another programmer in time for the second iteration of the software. The museum’s website says, “Thomas Knoll, a PhD student in computer vision at the University of Michigan, had written a program in 1987 to display and modify digital images. His brother John, working at the movie visual effects company Industrial Light & Magic, found it useful for editing photos, but it wasn’t intended to be a product.” The duo had developed the programme for personal use.

It was called "Display" in the build up to the launch, but was renamed to its current name and then licensed out to Adobe in 1989. It is easily the most popular photo-editing software in the world, selling more than 10 million copies in the first decade of its existence.


Images credit: Creative Bits

Published Date: Feb 15, 2013 14:09 PM | Updated Date: Feb 15, 2013 14:09 PM