Development
Early history
In 1987, Thomas Knoll, a PhD student at the University of Michigan, began writing a program on his Macintosh Plus to display grayscale images on a monochrome display. This program, called Display, caught the attention of his brother John Knoll, an Industrial Light & Magic employee, who recommended Thomas turn it into a full-fledged image editing program. Thomas took a six month break from his studies in 1988 to collaborate with his brother on the program, which had been renamed ImagePro. Later that year, Thomas renamed his program Photoshop and worked out a short-term deal with scanner manufacturer Barneyscan to distribute copies of the program with a slide scanner; a "total of about 200 copies of Photoshop were shipped" this way. During this time, John traveled to Silicon Valley and gave a demonstration of the program to engineers at Apple Computer Inc. and Russell Brown, art director at Adobe. Both showings were successful, and Adobe decided to purchase the license to distribute in September 1988.While John worked on plug-ins in California, Thomas remained in Ann Arbor writing program code. Photoshop 1.0 was released in 1990 for Macintosh exclusively.
Photoshop has strong ties with other Adobe software for media editing, animation, and authoring. The .PSD (Photoshop Document), Photoshop's native format, stores an image with support for most imaging options available in Photoshop. These include layers with masks, color spaces, ICC profiles, transparency, text, alpha channels and spot colors, clipping paths, and duotone settings. This is in contrast to many other file formats (e.g. .EPS or .GIF) that restrict content to provide streamlined, predictable functionality. Photoshop's popularity means that the .PSD format is widely used, and it is supported to some extent by most competing software. The .PSD file format can be exported to and from Adobe Illustrator, Adobe Premiere Pro, and After Effects, to make professional standard DVDs and provide non-linear editing and special effects services, such as backgrounds, textures, and so on, for television, film, and the Web. Photoshop is a pixel-based image editor, unlike Adobe Illustrator or CorelDraw, which is a vector-based image editor. Photoshop can utilize the color models RGB, lab, CMYK, grayscale, binary bitmap, and duotone. Photoshop has the ability to read and write raster and vector image formats such as .EPS, .PNG, .GIF, .JPEG, and Adobe Fireworks.
Photoshop CS3
is marketed with three main components of improvement over previous versions: "Work more productively, edit with unrivalled power, and composite with breakthrough tools."[7] New features propagating productivity include streamlined interface, improved Camera Raw, better control over print options, enhanced PDF support, and better management with Adobe Bridge. Editing tools new to CS3 are the Clone Source palette and nondestructive Smart Filters, and other features such as the Brightness/Contrast adjustment and Vanishing Point module were enhanced. The Black and White adjustment option improves users control over manual grayscale conversions with a dialog box similar to that of Channel Mixer. Compositing is assisted with Photoshop's new Quick Selection and Refine Edge tools and improved image stitching technology. CS3 Extended contains all features of CS3 plus tools for editing and importing some 3D graphics file formats, enhancing video, and comprehensive image analysis tools, utilizing MATLAB integration and DICOM file support.
Photoshop CS4
features additions such as the ability to paint directly on 3D models, wrap 2D images around 3D shapes, convert gradient maps to 3D objects, add depth to layers and text, get print-quality output with the new ray-tracing rendering engine, and enjoy exporting to supported common 3D formats; the new Adjustment and Mask Panels; Content-aware scaling (also known as seam carving[9]); Fluid Canvas Rotation and File display options.[10] On 30 April, Adobe released Photoshop CS4 Extended, which includes all the same features of Adobe Photoshop CS4 with the addition of capabilities for scientific imaging, 3D, and high end film and video users. The successor to Photoshop CS3, Photoshop CS4 is the first 64-bit Photoshop on consumer computers (only on Windows – the OS X version is still 32-bit only.)
