Norme d'affichage
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Plusieurs normes d'affichage ont été utilisé dans l'histoire des PC. Elles consistent souvent en une combinaison d'une définition d'écran (qui définit la largeur et la hauteur en pixels, la profondeur des couleurs, en bits) et d'une fréquence de rafraîchissement (en Hz).
[modifier] Normes
A number of common resolutions have been used with computers descended from the original IBM PC. Some of these are now supported by other families of personal computers. These are de-facto standards, usually originated by one manufacturer and reverse-engineered by others, though the VESA group has co-ordinated the efforts of several leading video display adapter manufacturers. Video standards associated with IBM-PC-descended personal computers include:
| Norme vidéo | Description | Définition d'écran (pixels) | Rapport largeur/hauteur | Profondeur des couleurs (2^bpp colors) |
|---|---|---|---|---|
| MDA | Monochrome Display Adapter, the original standard on IBM PCs and IBM PC XTs with 4 KB video RAM. Introduced in 1981 by IBM. Supports text mode only. | 720×350 (text) | 72:35 | 1 bpp |
| CGA | Color Graphics Adapter. Introduced in 1981 by IBM, as the first color display standard for the IBM PC. The standard CGA graphics cards were equipped with 16 KB video RAM. | 640×200 320×200 160×200 |
16:5 16:10 4:5 |
1 bpp 2 bpp 4 bpp |
| Hercules | A monochrome display capable of sharp text and graphics for its time of introduction. Very popular with the Lotus 1-2-3 spreadsheet, which was one of the PC's first killer apps. Introduced in 1982. | 720×348 | 60:29 | 1 bpp |
| EGA | Enhanced Graphics Adapter. Introduced in 1984 by IBM. A resolution of 640 × 350 pixels of 16 different colors (4 bits per pixel, or bpp), selectable from a 64-color palette (2 bits per each of red-green-blue). | 640×350 | 64:35 | 4 bpp |
| Professional Graphics Controller | With on-board 2D and 3D acceleration introduced in 1984 for the 8-bit PC-bus, intended for CAD applications, a triple-board display adapter with built-in processor, and displaying video with a 60 Hz frame rate. | 640×480 | 4:3 | 8 bpp |
| MCGA | Multicolor Graphics Adapter. Introduced on selected PS/2 models in 1987, with reduced cost compared to VGA. MCGA had a 320x200 256 color (from a 262,144 color palette) mode, and a 640x480 mode only in monochrome due to 64k video memory, compared to the 256k memory of VGA. | 320×200 640×480 |
16:10 4:3 |
8 bpp 1 bpp |
| 8514 | Precursor to XGA and released about the same time as VGA in 1987. 8514/A cards displayed interlaced video at 43.5 Hz. | 1024×768 | 4:3 | 8 bpp |
| VGA | Video Graphics Array, introduced in 1987 by IBM. VGA is actually a set of different resolutions, but is most commonly used today to refer to 640 × 480 pixel displays with 16 colors (4 bits per pixel) and a 4:3 aspect ratio. Other display modes are also defined as VGA, such as 320 × 200 at 256 colors (8 bits per pixel) and a text mode with 720 × 400 pixels. VGA displays and adapters are generally capable of Mode X graphics, an undocumented mode to allow increased non-standard resolutions. | 640×480 640×350 320×200 720×400 (text) |
4:3 64:35 16:10 9:5 |
4 bpp 4 bpp 4/8 bpp 4 bpp |
| SVGA | Super VGA, a video display standard created by VESA for IBM PC compatible personal computers. Introduced in 1989. | 800×600 | 4:3 | 4 bpp |
| XGA | Extended Graphics Array is an IBM display standard introduced in 1990. XGA-2 added 1024 × 768 support for high color and higher refresh rates, improved performance, and support for 1360 × 1024 in 16 colors (4 bits per pixel). | 1024×768 640×480 |
4:3 4:3 |
8 bpp 16 bpp |
| QVGA | Quarter VGA (320x240) | 320×240 | 4:3 | |
| QQVGA | Quarter QVGA (160x120) | 160×120 | 4:3 | |
| WXGA | Widescreen Extended Graphics Array is a version of the XGA format. This display aspect ratio is becoming popular in some recent notebook computers. | 1280×720 or 1280x800 | 16:9 or 16:10 | 32 bpp |
| SXGA | Super XGA, a widely used de facto 32 bit Truecolor standard, with an unusual aspect ratio of 5:4 instead of the more common 4:3 which means, if scaled, images appear wider on SXGA displays than most other resolutions. The resolution probably should have been 1280 × 960 which is a popular standard resolution for Unix workstations.
|
1280×1024 | 5:4 | 32 bpp |
| WSXGA, or WXGA+ | Widescreen Extended Graphics Array PLUS is a version of the WXGA format. This display aspect ratio is becoming popular in some recent notebook computers. | 1440×900 | 16:10 | 32 bpp |
| UXGA | Ultra XGA is a de facto Truecolor standard. | 1600×1200 | 4:3 | 32 bpp |
| WUXGA | Widescreen Ultra Extended Graphics Array is a version of the UXGA format. This display aspect ratio was becoming popular in high end 15" and 17" widescreen notebook computers. | 1920×1200 | 16:10 | 32 bpp |
| QXGA | Quad Extended Graphics Array | 2048×1536=3.1M | 4:3 | 32 bpp |
| WQXGA | Widescreen Quad Extended Graphics Array is a version of the XGA format. This display aspect ratio is becoming popular in some recent desktop monitors. | 2560×1600=4.1M | 16:10 | 32 bpp |
| QSXGA | Quad Super Extended Graphics Array | 2560×2048=5.2M | 5:4 | 32 bpp |
| WQSXGA | Wide Quad Super Extended Graphics Array | 3200×2048=6.6M | 25:16 | 32 bpp |
| QUXGA | Quad Ultra Extended Graphics Array | 3200×2400=7.7M | 4:3 | 32 bpp |
| WQUXGA | Wide Quad Ultra Extended Graphics Array. The IBM T220/T221 LCD monitors supported this resolution, but they are no longer available. | 3840×2400=9.2M | 16:10 | 32 bpp |
| HXGA | Hex[adecatuple] Extended Graphics Array | 4096×3072=12.6M | 4:3 | 32 bpp |
| WHXGA | Wide Hex[adecatuple] Extended Graphics Array | 5120×3200=16.4M | 16:10 | 32 bpp |
| HSXGA | Hex[adecatuple] Super Extended Graphics Array | 5120×4096=21M | 5:4 | 32 bpp |
| WHSXGA | Wide Hex[adecatuple] Super Extended Graphics Array | 6400×4096=26M | 25:16 | 32 bpp |
| HUXGA | Hex[adecatuple] Ultra Extended Graphics Array | 6400×4800=31M | 4:3 | 32 bpp |
| WHUXGA | Wide Hex[adecatuple] Ultra Extended Graphics Array | 7680×4800=37M | 16:10 | 32 bpp |
[modifier] Significations des sigles
Bien que les lettres S (pour super) et U (pour ultra) fréquemment présentes n'aient pas de réelles significations sur la façon dont elle modifient les définitions de base, c'est le cas pour d'autres :
- Quarter (Q)
- A quarter of the base resolution. E.g. QVGA, a term for a 320×240 resolution, half the width and height of VGA, hence the quarter total resolution. This prefix is usually for "Quad" in higher resolutions.
- Wide (W)
- The base resolution increased, and not lowered, for square or near-square pixels on a widescreen display, usually with an aspect ratio of either 16:9 or 16:10.
- Quad(ruple) (Q)
- Four times as many pixels compared to the base resolution, i.e. twice the horizontal and vertical resolution respectively.
- Hex(adecatuple) (H)
- Sixteen times as many pixels compared to the base resolution, i.e. four times the horizontal and vertical resolutions respectively.
- Ultra (U)
- eXtended (X)
Ces lettre sont souvent utilisées simultanément comme c'est le cas avec WQXGA et WHUXGA.
[modifier] Voir aussi
| Normes d'affichage | Comparaison des tailles |
|---|---|
| Matériel vidéo |  |
| MDA | Hercules | CGA | EGA | VGA | MCGA | 8514 | XGA | |
| Définitions d'affichage | |
| QVGA | VGA | SVGA | XGA | SXGA | SXGA+ | UXGA | QXGA | QSXGA | QUXGA | HXGA | HSXGA | HUXGA | QHXGA | H²XGA | |
| Écrans larges | |
| WSVGA | WXGA-H | WXGA | WXGA+ | WSXGA | WSXGA+ | WUXGA | WUXGA+ | WQXGA | WQSXGA | WQUXGA | WHXGA | WHSXGA | UHDV | WHUXGA |
