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LOGO.SYS is a core system file used by the Windows 9x family of operating systems to display its boot-up message.
LOGO.SYS is a system file that is used as part of the startup process found in the Windows 9x family of operating systems such as Windows 95, Windows 98, and Windows Me to display their boot screens. It is not present in the Windows NT family of operating systems such as Windows NT 4.0, Windows 2000, and Windows XP, as they used various different methods to display their boot screens.
There are three variants of the file:
LOGO=0 setting to the Options section in the MS-DOS 7 configuration file MSDOS.SYS.LOGO.SYS is in fact an 8-bit RLE-encoded Windows bitmap file with a resolution of exactly 320×400 pixels at 256 colors. This is displayed in the otherwise little-used 320x400 VGA graphics mode, a compromise to allow the display of a 256-color image with high vertical (but not horizontal) resolution on all compatible systems, even those with plain VGA cards (which could only show 16 colors with high horizontal resolution) and without needing any additional graphics drivers. The mode appears, to any attached monitor, to be identical to the more common 640x400 graphics or 720x400 text modes, and is therefore stretched to a standard 4:3 aspect ratio (meaning the pixels appear to be 1.67x (2/1.2) wider than they are tall, instead of square - as they would be on a full 640x480 VGA display) on a typical 4:3 monitor of the time, and on monitors of other shapes (5:4, 16:9, etc.) when set to display standard video modes in their original aspects with letterbox borders. This lent the startup screens a peculiar, characteristic "feel" and made them more suited to certain subjects (which disguised the horizontal blockiness or made good use of the vertical resolution) than others (which accentuated it), meaning some skill was needed in choosing an image that would still be aesthetically pleasing - or even clear enough to be properly interpreted - once resized.
For LOGO.SYS or the equivalent embedded image in IO.SYS, Windows will also animate the image's color information using palette rotation; the image is static, but may have the illusion of movement as colors are changed.
As the files are standard RLE-compressed .BMPs (with an entirely optional custom tag segment) renamed to ".SYS", they may be opened and edited using image editing tools such as MS Paint, and the contents replaced with user-selected pictures; the only conversion needed is to change the file extension, and to ensure they are in the correct resolution and color depth (with dithering if needed). However, the process is not foolproof:
biClrImportant field of the BITMAPINFOHEADER structure. Image editing software usually discarded this data, so it was often not possible to retain it. Some logo creation utilities were specifically created to restore the cycling function and allow creating custom animations.PCX, standing for PiCture eXchange, was an image file format developed by the now-defunct ZSoft Corporation of Marietta, Georgia, United States. It was the native file format for PC Paintbrush and became one of the first widely accepted DOS imaging standards, although it has since been succeeded by more sophisticated image formats, such as BMP, JPEG, and PNG. PCX files commonly stored palette-indexed images ranging from 2 or 4 colors to 16 and 256 colors, although the format has been extended to record true-color (24-bit) images as well.
In computer graphics and digital photography, a raster graphics represents a two-dimensional picture as a rectangular matrix or grid of square pixels, viewable via a computer display, paper, or other display medium. A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel. Raster images are stored in image files with varying dissemination, production, generation, and acquisition formats.
Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the IBM PC compatible industry within three years. The term can now refer to the computer display standard, the 15-pin D-subminiature VGA connector, or the 640 × 480 resolution characteristic of the VGA hardware.
The Enhanced Graphics Adapter (EGA) is an IBM PC graphics adapter and de facto computer display standard from 1984 that superseded the CGA standard introduced with the original IBM PC, and was itself superseded by the VGA standard in 1987. In addition to the original EGA card manufactured by IBM, many compatible third-party cards were manufactured, and EGA graphics modes continued to be supported by VGA and later standards.
The BMP file format or bitmap, is a raster graphics image file format used to store bitmap digital images, independently of the display device, especially on Microsoft Windows and OS/2 operating systems.
Color depth or colour depth, also known as bit depth, is either the number of bits used to indicate the color of a single pixel, or the number of bits used for each color component of a single pixel. When referring to a pixel, the concept can be defined as bits per pixel (bpp). When referring to a color component, the concept can be defined as bits per component, bits per channel, bits per color, and also bits per pixel component, bits per color channel or bits per sample (bps). Modern standards tend to use bits per component, but historical lower-depth systems used bits per pixel more often.
Mode 13h is the standard 256-color mode on VGA graphics hardware introduced in 1987 with the IBM PS/2. It has a resolution of 320×200 pixels. It was used extensively in computer games and art/animation software of the late 1980s and early to mid-1990s. "13h" refers to the number of the mode in the VGA BIOS. The "h" stands for hexadecimal.
The Color Graphics Adapter (CGA), originally also called the Color/Graphics Adapter or IBM Color/Graphics Monitor Adapter, introduced in 1981, was IBM's first color graphics card for the IBM PC and established a de facto computer display standard.
The Multi-Color Graphics Array or MCGA is a video subsystem built into the motherboard of the IBM PS/2 Model 30, introduced on September 2, 1986, and Model 25, introduced later on August 11, 1987; no standalone MCGA cards were ever made.
ANSI.SYS is a device driver in the DOS family of operating systems that provides extra console functions through ANSI escape sequences. It is partially based upon a subset of the text terminal control standard proposed by the ANSI X3L2 Technical Committee on Codes and Character Sets.
Hold-And-Modify, usually abbreviated as HAM, is a display mode of the Commodore Amiga computer. It uses a highly unusual technique to express the color of pixels, allowing many more colors to appear on screen than would otherwise be possible. HAM mode was commonly used to display digitized photographs or video frames, bitmap art and occasionally animation. At the time of the Amiga's launch in 1985, this near-photorealistic display was unprecedented for a home computer and it was widely used to demonstrate the Amiga's graphical capability. However, HAM has significant technical limitations which prevent it from being used as a general purpose display mode.
In computing, indexed color is a technique to manage digital images' colors in a limited fashion, in order to save computer memory and file storage, while speeding up display refresh and file transfers. It is a form of vector quantization compression.
GrafX2 is a bitmap graphics editor inspired by the Amiga programs Deluxe Paint and Brilliance. It is free software and distributed under the GPL-2.0-only license.
VGA text mode was introduced in 1987 by IBM as part of the VGA standard for its IBM PS/2 computers. Its use on IBM PC compatibles was widespread through the 1990s and persists today for some applications on modern computers. The main features of VGA text mode are colored characters and their background, blinking, various shapes of the cursor, and loadable fonts. The Linux console traditionally uses hardware VGA text modes, and the Win32 console environment has an ability to switch the screen to text mode for some text window sizes.
The Windows 9x series of operating systems refers to the monolithic kernel which powers these operating systems. The basic code is similar in function to MS-DOS. As a 16-/32-bit hybrid, it requires support from MS-DOS to operate.
Tandy Graphics Adapter is a computer display standard for the Tandy 1000 series of IBM PC compatibles, which has compatibility with the video subsystem of the IBM PCjr but became a standard in its own right.
Composite artifact colors is a designation commonly used to address several graphic modes of some 1970s and 1980s home computers. With some machines, when connected to an NTSC TV or monitor over composite video outputs, the video signal encoding allowed for extra colors to be displayed, by manipulating the pixel position on screen, not being limited by each machine's hardware color palette.