Misplaced Pages

#818181

108-469: As of 2019, the most common image colorspace in graphics cards is the RGB color model with 8 bits per pixel color depth . Using this technique, 8 bits per pixel are used to describe the luminance level in each of the RGB channels , therefore 24 bits fully describe the color of each pixel. The full system palette for such hardware therefore has 2 colors. The objective of the usage of smaller palettes via CLUTs

216-475: A bitmap or bilevel image ) and not an indexed color image. If simple video overlay is intended through a transparent color , one palette entry is specifically reserved for this purpose, and it is discounted as an available color. Some machines, such as the MSX series, had the transparent color reserved by hardware. Indexed color images with palette sizes beyond 256 entries are rare. The practical limit

324-578: A graphics card comes in the form of a printed circuit board (expansion board) which is to be inserted into an expansion slot. Others may have dedicated enclosures, and they are connected to the computer via a docking station or a cable. These are known as external GPUs (eGPUs). Graphics cards are often preferred over integrated graphics for increased performance. Graphics cards, also known as video cards or graphics processing units (GPUs), have historically evolved alongside computer display standards to accommodate advancing technologies and user demands. In

432-450: A slideshow . When it is necessary to show multiple images together, as in a mosaic of thumbnails , a common or master palette is often used, which encompasses as many different hues as possible into a single set, thereby limiting the overall accurate color availability. The following image is a mosaic of four different indexed color images rendered with a single shared master palette of 6-8-5 levels RGB plus 16 additional grays. Note

540-429: A transparent color, in order to perform a simple video overlay : superimposing a given image over a background in such way that some part of the overlapped image obscures the background and the remaining not. Superimposing film/TV titles and credits is a typical application of video overlay. In the image to be superimposed (indexed color is assumed), a given palette entry plays the role of the transparent color. Usually

648-430: A 17% fall from Q3 2012 levels. Shipments reached an annual total of 44 million in 2015. The sales of graphics cards have trended downward due to improvements in integrated graphics technologies; high-end, CPU-integrated graphics can provide competitive performance with low-end graphics cards. At the same time, graphics card sales have grown within the high-end segment, as manufacturers have shifted their focus to prioritize

756-428: A CLUT. The palette itself stores a limited number of distinct colors; 4, 16 or 256 are the most common cases. These limits are often imposed by the target architecture's display adapter hardware , so it is not a coincidence that those numbers are exact powers of two (the binary code ): 2  = 4, 2  = 16 and 2  = 256. While 256 values can be fit into a single 8- bit byte (and then

864-487: A GPU in the long term. Some graphics cards can be linked together to allow scaling graphics processing across multiple cards. This is done using either the PCIe bus on the motherboard or, more commonly, a data bridge. Usually, the cards must be of the same model to be linked, and most low end cards are not able to be linked in this way. AMD and Nvidia both have proprietary scaling methods, CrossFireX for AMD, and SLI (since

972-483: A RAMDAC, but they reconvert the analog signal back to digital before they can display it, with the unavoidable loss of quality stemming from this digital-to-analog-to-digital conversion. With the VGA standard being phased out in favor of digital formats, RAMDACs have started to disappear from graphics cards. The most common connection systems between the graphics card and the computer display are: Also known as D-sub , VGA

1080-509: A computer display that uses analog inputs such as cathode-ray tube (CRT) displays. The RAMDAC is a kind of RAM chip that regulates the functioning of the graphics card. Depending on the number of bits used and the RAMDAC-data-transfer rate, the converter will be able to support different computer-display refresh rates. With CRT displays, it is best to work over 75  Hz and never under 60 Hz, to minimize flicker. (This

1188-407: A given machine. Some indexed-color image file formats such as Graphics Interchange Format (GIF) allow the image's scan lines to be arranged in interleaved fashion (not linear order), which allows a low resolution version of the image to appear on screen while it is still downloading, so that the computer user can gain an idea of its contents during the seconds before the whole image arrives. Here

SECTION 10

#1732765190819

1296-405: A greater throughput of the same functionality as HDMI , it is expected to complement the interface, not replace it. Chronologically, connection systems between graphics card and motherboard were, mainly: The following table is a comparison between features of some interfaces listed above. Indexed color In computing, indexed color is a technique to manage digital images ' colors in

1404-511: A large motherboard with a proper configuration. Nvidia's GeForce GTX 590 graphics card can be configured in a four-card configuration. As stated above, users will want to stick to cards with the same performances for optimal use. Motherboards including ASUS Maximus 3 Extreme and Gigabyte GA EX58 Extreme are certified to work with this configuration. A large power supply is necessary to run the cards in SLI or CrossFireX. Power demands must be known before

1512-531: A limited 8-bit depth graphic display, it is necessary to load a given image's adaptive palette into the color hardware registers prior to loading the image surface itself into the frame buffer . To display different images with different adaptive palettes, they must be loaded one by one, as in a slideshow . Here are samples of four different indexed color images with color patches to show their respective (and largely incompatible) adaptive palettes: A single palette entry in an indexed color image can be designated as

1620-431: 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 . When an image is encoded in this way, color information is not directly carried by the image pixel data, but is stored in a separate piece of data called a color lookup table (CLUT) or palette : an array of color specifications. Every element in

1728-410: A major surge in price, with many retailers having stock shortages due to the significant demand among this market. Graphics card companies released mining-specific cards designed to run 24 hours a day, seven days a week , and without video output ports. The graphics card industry took a setback due to the 2020–21 chip shortage . A modern graphics card consists of a printed circuit board on which

1836-422: A modern graphics card is also a computer unto itself. A heat sink is mounted on most modern graphics cards. A heat sink spreads out the heat produced by the graphics processing unit evenly throughout the heat sink and unit itself. The heat sink commonly has a fan mounted to cool the heat sink and the graphics processing unit. Not all cards have heat sinks, for example, some cards are liquid-cooled and instead have

1944-435: A palette for indexed color image files. In general, to apply a gamma correction directly to the color map is bad practice, due to the original RGB color values being lost. It is better to apply the gamma correction with the display hardware (most modern display adapters support this feature), or as an active intermediate step of the rendering software through color management , which preserves the original color values. Only when

2052-570: A proper supply is installed. For the four card configuration, a 1000+ watt supply is needed. With any relatively powerful graphics card, thermal management cannot be ignored. Graphics cards require well-vented chassis and good thermal solutions. Air or water cooling are usually required, though low end GPUs can use passive cooling. Larger configurations use water solutions or immersion cooling to achieve proper performance without thermal throttling. SLI and Crossfire have become increasingly uncommon as most games do not fully utilize multiple GPUs, due to

2160-501: A result visually closer to the original one. Here is a typical indexed 256-color image and its own palette (shown as a rectangle of swatches): How the colors are encoded within the color palette map of a given indexed color image depends on the target platform. Many early personal and home computers had very limited hardware palettes that could produce a very small set of colors. In these cases, each pixel's value mapped directly onto one of these colors. Well-known examples include

2268-402: A series of bit planes (in a configuration called planar ), in which the related bits of a single pixel are split among several independent bitmaps . Thus, the pixel bits are conceptually aligned along the 3D Z-axis. (The "depth" concept here is not the same as that of pixel depth .) Early image file formats, such as PIC , stored little more than a bare memory dump of the video buffer of

SECTION 20

#1732765190819

2376-439: A single indexed color pixel also occupies a single byte), pixel indices with 16 (4-bit, a nibble ) or fewer colors can be packed together into a single byte (two nibbles per byte, if 16 colors are employed, or four 2-bit pixels per byte if using 4 colors). Sometimes, 1-bit (2-color) values can be used, and then up to eight pixels can be packed into a single byte; such images are considered binary images (sometimes referred as

2484-421: A water block; additionally, cards from the 1980s and early 1990s did not produce much heat, and did not require heat sinks. Most modern graphics cards need proper thermal solutions. They can be water-cooled or through heat sinks with additional connected heat pipes usually made of copper for the best thermal transfer. The video BIOS or firmware contains a minimal program for the initial set up and control of

2592-401: Is a computer expansion card that generates a feed of graphics output to a display device such as a monitor . Graphics cards are sometimes called discrete or dedicated graphics cards to emphasize their distinction to an integrated graphics processor on the motherboard or the central processing unit (CPU). A graphics processing unit (GPU) that performs the necessary computations

2700-414: Is a compact audio/video interface for transferring uncompressed video data and compressed/uncompressed digital audio data from an HDMI-compliant device ("the source device") to a compatible digital audio device, computer monitor , video projector , or digital television . HDMI is a digital replacement for existing analog video standards. HDMI supports copy protection through HDCP . DisplayPort

2808-668: Is a digital display interface developed by the Video Electronics Standards Association (VESA). The interface is primarily used to connect a video source to a display device such as a computer monitor , though it can also be used to transmit audio, USB, and other forms of data. The VESA specification is royalty-free . VESA designed it to replace VGA , DVI , and LVDS . Backward compatibility to VGA and DVI by using adapter dongles enables consumers to use DisplayPort fitted video sources without replacing existing display devices. Although DisplayPort has

2916-430: Is an analog-based standard adopted in the late 1980s designed for CRT displays, also called VGA connector . Today, the VGA analog interface is used for high definition video resolutions including 1080p and higher. Some problems of this standard are electrical noise , image distortion and sampling error in evaluating pixels. While the VGA transmission bandwidth is high enough to support even higher resolution playback,

3024-473: Is an example of a typical vertically interleaved download in four steps: As seen here, the image has been divided into four groups of lines: group A contains every fourth line, group B contains lines immediately following ones in group A, group C likewise contains the lines immediately following those in group B, and group D contains the remaining lines, which are between group C lines (immediately above) and group A lines (immediately below). These are stored into

3132-430: Is around 12-bit per pixel, 4,096 different indices. To use indexed 16 bpp or more does not provide the benefits of the indexed color images' nature, due to the color palette size in bytes being greater than the raw image data itself. Also, useful direct RGB Highcolor modes can be used from 15 bpp and up. If an image has many subtle color shades, it is necessary to select a limited repertoire of colors to approximate

3240-495: Is extensively used in the demoscene . The Microsoft Windows boot logo screen in Windows 95, 98, ME, and 2000 Professional (which uses VGA 320x200x256 color display mode because it is the greatest common denominator on all PCs) employs this technique for the scrolling gradient bar across the bottom of the screen; the picture is a static image with no pixels rewritten after it is initially displayed. Custom boot screen images could tap

3348-486: Is limited to supplying 75 watts. Modern graphics cards with a power consumption of over 75 watts usually include a combination of six-pin (75 W) or eight-pin (150 W) sockets that connect directly to the power supply. Providing adequate cooling becomes a challenge in such computers. Computers with multiple graphics cards may require power supplies over 750 watts. Heat extraction becomes a major design consideration for computers with two or more high-end graphics cards. As of

Palette (computing) - Misplaced Pages Continue

3456-404: Is lost, it can be nearly impossible to restore it. Here is an example of what happens when an indexed color image (the previous parrot) has been associated with an incorrect color palette: Indexed color graphic modes for display adapters have the 16- or 256-color limit imposed by hardware. Indexed color images with rich but incompatible palettes can only be accurately displayed one at a time, as in

3564-601: Is not a problem with LCD displays, as they have little to no flicker. ) Due to the growing popularity of digital computer displays and the integration of the RAMDAC onto the GPU die, it has mostly disappeared as a discrete component. All current LCD/plasma monitors and TVs and projectors with only digital connections work in the digital domain and do not require a RAMDAC for those connections. There are displays that feature analog inputs ( VGA , component, SCART , etc.) only . These require

3672-480: Is not being used to hold any translucency data and is set to zero. By contrast, PNG supports alpha channels in palette entries, enabling semi-transparency in paletted images. When dealing with truecolor images, some video mixing equipment can employ the RGB triplet (0,0,0) (no red, no green, no blue: the darkest shade of black, sometimes referred as superblack in this context) as the transparent color. At design time, it

3780-494: Is not enabled on the Blu-ray disc. Digital Visual Interface is a digital-based standard designed for displays such as flat-panel displays ( LCDs , plasma screens, wide high-definition television displays) and video projectors. There were also some rare high-end CRT monitors that use DVI. It avoids image distortion and electrical noise, corresponding each pixel from the computer to a display pixel, using its native resolution . It

3888-497: Is placed anywhere over the background image, and it is blended in such way that if the pixel color index is the transparent color, the background pixel is kept, otherwise it is replaced. This technique is used for pointers, in typical 2-D videogames for characters, bullets and so on (the sprites ), video titling and other image mixing applications. Some early computers, as Commodore 64 , MSX and Amiga supports sprites and/or full screen video overlay by hardware. In these cases,

3996-404: Is replaced by the so-called magic pink . The same way, typical desktop publishing software can assume pure white, RGB triplet (255,255,255) from photos and illustrations to be excluded in order to let the text paragraphs to invade the image's bounding box for irregular text arrangement around the image's subjects. 2-D painting programs , like Microsoft Paint and Deluxe Paint , can employ

4104-420: Is sometimes referred to as a uniform palette . The normal human eye has sensibility to the three primary colors in different degrees: the more to the green, the less to the blue. So RGB arrangements can take advantage of this by assigning more levels for the green component and fewer to the blue. A master palette built this way can be filled with up to 8R×8G×4B = 256 colors , but this does not leave space in

4212-504: Is termed a duopoly . AMD and Nvidia also build and sell graphics cards, which are termed graphics add-in-boards (AIBs) in the industry. (See Comparison of Nvidia graphics processing units and Comparison of AMD graphics processing units .) In addition to marketing their own graphics cards, AMD and Nvidia sell their GPUs to authorized AIB suppliers, which AMD and Nvidia refer to as "partners". The fact that Nvidia and AMD compete directly with their customer/partners complicates relationships in

4320-634: Is the main component in a graphics card, but the acronym "GPU" is sometimes also used to erroneously refer to the graphics card as a whole. Most graphics cards are not limited to simple display output. The graphics processing unit can be used for additional processing, which reduces the load from the CPU. Additionally, computing platforms such as OpenCL and CUDA allow using graphics cards for general-purpose computing . Applications of general-purpose computing on graphics cards include AI training , cryptocurrency mining , and molecular simulation . Usually,

4428-485: Is to lower the number of bits per pixel by reducing the set of possible colors that are to be handled at once (often using adaptive methods). Each possible color is assigned an index, which allows each color to be referenced using less information than needed to fully describe the color. An example is the 256-color palette commonly used in the GIF file format, in which 256 colors to be used to represent an image are selected from

Palette (computing) - Misplaced Pages Continue

4536-646: Is worth noting that most manufacturers include a DVI- I connector, allowing (via simple adapter) standard RGB signal output to an old CRT or LCD monitor with VGA input. These connectors are included to allow connection with televisions , DVD players , video recorders and video game consoles . They often come in two 10-pin mini-DIN connector variations, and the VIVO splitter cable generally comes with either 4 connectors ( S-Video in and out plus composite video in and out), or 6 connectors (S-Video in and out, component YP B P R out and composite in and out). HDMI

4644-463: The Apple II , Commodore 64 and IBM PC CGA , all of which included hardware that could produce a fixed set of 16 colors. In these cases, an image can encode each pixel with 4-bits, directly selecting the color to use. In most cases, however, the display hardware supports additional modes where only a subset of those colors can be used in a single image, a useful technique to save memory. For instance,

4752-785: The BMP file format indexed color mode stores its entries in BGR order rather than RGB, and has (in the current version) an additional unused byte for padding to conform to 32-bit word alignment during processing, but it is essentially still a 24-bit RGB color encoding. (An earlier version of the BMP format used three bytes per 24-bit color map table entry, and many files in that format are still in circulation, so many modern programs that read BMP files support both variations.) Except for very low resolution graphic modes, early home and personal computers rarely implemented an "all-pixels-addressable" design - that is,

4860-606: The Nvidia GeForce RTX 30 series, Ampere architecture , a custom flashed RTX 3090 named "Hall of Fame" has been recorded to reach a peak power draw as high as 630 watts. A standard RTX 3090 can peak at up to 450 watts. The RTX 3080 can reach up to 350 watts, while a 3070 can reach a similar, if not slightly lower peak power draw. Ampere cards of the Founders Edition variant feature a "dual axial flow through" cooler design, which includes fans above and below

4968-451: The Turing generation, superseded by NVLink ) for Nvidia. Cards from different chip-set manufacturers or architectures cannot be used together for multi-card scaling. If graphics cards have different sizes of memory, the lowest value will be used, with the higher values disregarded. Currently, scaling on consumer-grade cards can be done using up to four cards. The use of four cards requires

5076-560: The Win32 API . The applicability of palettes in Highcolor and Truecolor display modes becomes questionable. These APIs deals with the so-called "system palette" and with many "logical palettes". The "system palette" is a copy in RAM of the color display's hardware registers, primarily a physical palette, and it is a unique, shared common resource of the system. At boot, it is loaded with

5184-529: The default system palette (mainly a "master palette" which works well enough with most programs). When a given application intends to output colorized graphics and/or images, it can set their own "logical palette", that is, its own private selection of colors (up to 256). It is supposed that every graphic element that the application tries to show on screen employs the colors of its logical palette. Every program can manage freely one or more logical palettes without further expected interference (in advance). Before

5292-411: The transparent color technique. By manipulating the color hardware registers ( Color look-up table or CLUT) of the display adapter in the indexed color graphic modes, full-screen color-animation effects can be achieved without redrawing the image - that is, at low CPU time cost; a single change of the register values affects the whole screen at once. Color-map animation, also known as Color cycling ,

5400-437: The truecolor original one by using adaptive palettes (sometimes termed adaptative palettes ), in which the colors are selected or quantized through some algorithm directly from the original image (by picking the most frequent colors). This way, and with further dithering , the indexed color image can nearly match the original. But this creates a heavy dependence between the image pixels and its adaptive palette. Assuming

5508-771: The 1980s include CGA , EGA , and VGA (for IBM PC compatibles ), the Atari ST , and Amiga 's OCS and AGA . Image files exchanged over the CompuServe net in the early 1990s were encapsulated in the GIF format. Later, the HTML web pages used the GIF along with other indexed color-supporting file formats such as PNG , to exchange limited-color images quickly and store them in limited storage space. Most image file formats that support indexed color images also commonly support some compression scheme, enhancing their ability to store

SECTION 50

#1732765190819

5616-563: The 4,096 colors of the VT241 terminal in ReGIS graphics mode. In these cases it was common for the image to only allow a small subset of the total number of colors to be displayed at one time, up to 16 at once on the Atari and VT241. Generally, these systems worked identically to their less-colorful brethren, but a key difference was that there were too many colors in the palette to directly encode in

5724-482: The CGA's 320×200 resolution mode could show only four of the 16 colors at one time. As the palettes were entirely proprietary, an image generated on one platform cannot be directly viewed properly on another. Other machines of this era had the ability to generate a larger set of colors, but generally only allowed a subset of those to be used in any one image. Examples include the 256-color palette on Atari 8-bit machines or

5832-437: The CPU and system RAM, therefore the overall performance for a computer could improve in addition to increased performance in graphics processing. Such improvements to performance can be seen in video gaming , 3D animation , and video editing . Both AMD and Intel have introduced CPUs and motherboard chipsets which support the integration of a GPU into the same die as the CPU. AMD advertises CPUs with integrated graphics under

5940-514: The DIMM or PCIE slots. This can be fixed with a larger computer case such as mid-tower or full tower. Full towers are usually able to fit larger motherboards in sizes like ATX and micro ATX. In the late 2010s and early 2020s, some high-end graphics card models have become so heavy that it is possible for them to sag downwards after installing without proper support, which is why many manufacturers provide additional support brackets. GPU sag can damage

6048-544: The GeForce RTX 2080 Ti Founder's Edition averaged 300 watts of power consumption. While CPU and power supply manufacturers have recently aimed toward higher efficiency, power demands of graphics cards continued to rise, with the largest power consumption of any individual part in a computer. Although power supplies have also increased their power output, the bottleneck occurs in the PCI-Express connection, which

6156-670: The Macintosh graphical user interface, allowed for the rapid rendering of bitmapped graphics, fonts, and shapes, and the introduction of such hardware-based enhancements signaled an era of specialized graphics processing in consumer machines. The evolution of graphics processing took a major leap forward in the mid-1990s with 3dfx Interactive 's introduction of the Voodoo series , one of the earliest consumer-facing GPUs that supported 3D acceleration. These cards, however, were dedicated entirely to 3D processing and lacked 2D support, necessitating

6264-961: The RIVA 128 was one of the first consumer-facing GPUs to integrate both 3D and 2D processing units on a single chip. This innovation simplified the hardware requirements for end-users, as they no longer needed separate cards for 2D and 3D rendering, thus paving the way for the widespread adoption of more powerful and versatile GPUs in personal computers. In contemporary times, the majority of graphics cards are built using chips sourced from two dominant manufacturers: AMD and Nvidia . These modern graphics cards are multifunctional and support various tasks beyond rendering 3D images for gaming. They also provide 2D graphics processing, video decoding , TV output , and multi-monitor setups . Additionally, many graphics cards now have integrated sound capabilities, allowing them to transmit audio alongside video output to connected TVs or monitors with built-in speakers, further enhancing

6372-448: The ability to change a single pixel to any of the available colors independently. Their limitations came from employing separate color attribute or color RAM areas, leading to attribute clash effects. Also, the pixel bits and/or the scan lines of the video memory were commonly arranged in odd ways convenient for the video generator hardware (thus saving hardware costs in a cost-competitive market), but sometimes creating difficulty for

6480-444: The array represents a color, indexed by its position within the array. Each image pixel does not contain the full specification of its color, but only its index into the palette . This technique is sometimes referred as pseudocolor or indirect color , as colors are addressed indirectly. Early graphics display systems that used 8-bit indexed color with frame buffers and color lookup tables include Shoup's SuperPaint (1973) and

6588-553: The card to dissipate as much heat as possible towards the rear of the computer case. A similar design was used by the Sapphire Radeon RX Vega 56 Pulse graphics card. Graphics cards for desktop computers have different size profiles, which allows graphics cards to be added to smaller-sized computers. Some graphics cards are not of the usual size, and are named as "low profile". Graphics card profiles are based on height only, with low-profile cards taking up less than

SECTION 60

#1732765190819

6696-440: The centers of remaining bands that are not yet filled with image data. This method, with four or eight groups of lines, was commonly used on the early World Wide Web during the second half of the 1990s. Rather than leaving the background (black) showing as in the illustration above, the partial image was often presented on screen by duplicating each line to fill the space below it down to the next received image line. The end result

6804-536: The colors — simplifying the hardware design — while the software can treat the number per levels used abstractly and manage the RGB colors in a device-independent fashion. With colors stored in RGB format within the palettes of indexed image files, any image can be displayed (through appropriate transformations) on any such system, regardless of the color depth used in the hardware implementation. Today, display hardware and image file formats that deal with indexed color images almost exclusively manage colors in RGB format,

6912-404: The components are mounted. These include: A graphics processing unit ( GPU ), also occasionally called visual processing unit ( VPU ), is a specialized electronic circuit designed to rapidly manipulate and alter memory to accelerate the building of images in a frame buffer intended for output to a display. Because of the large degree of programmable computational complexity for such a task,

7020-468: The cycled colors to animate other parts of the images. The main disadvantage of using indexed color is the limited set of simultaneous colors per image. Small 4- or 16-color palettes are still acceptable for little images ( icons ) or very simple graphics, but to reproduce real life images they become nearly useless. Some techniques, such as color quantization , anti-aliasing and dithering combined together can create indexed 256-color images comparable to

7128-495: The de facto standard encoding being the so-called truecolor or 24-bit RGB , with 16,777,216 different possible colors . However, indexed color images are not genuinely constrained to a 24-bit RGB color encoding; image palettes can hold any type of color encoding. For example, the PDF file format does support indexed color in other colorspaces, notably CMYK , and Adobe Distiller by default will convert images to indexed color whenever

7236-476: The development of modern graphical capabilities. In the late 1980s, advancements in personal computing led companies like Radius to develop specialized graphics cards for the Apple Macintosh II . These cards were unique in that they incorporated discrete 2D QuickDraw capabilities, enhancing the graphical output of Macintosh computers by accelerating 2D graphics rendering. QuickDraw, a core part of

7344-537: The fact that many programs fail to handle this event, and their windows will become corrupt in this situation. An application can force the system palette to be loaded with specific colors (even in a specific order), "tricking" the system by telling it they are color entries intended for animation (quick color changes of the colors in the physical palette at specific entries). The system will then assume that those hardware palette entries no longer are free for its palette color management algorithm. The final result depends on

7452-455: The fact that most users cannot afford them. Multiple GPUs are still used on supercomputers (like in Summit ), on workstations to accelerate video and 3D rendering, visual effects , for simulations, and for training artificial intelligence. A graphics driver usually supports one or multiple cards by the same vendor and has to be written for a specific operating system. Additionally,

7560-425: The file in the order A, C, B, D, so that when the file is transmitted the second received group (C) of lines lie centered between the lines of the first group, yielding the most spatially uniform and recognizable image possible, composed of only two of the groups of lines. The same technique can be applied with more groups (e.g. eight), in which case at each step the next group to be sent contains lines lying at or near

7668-439: The gaming and enthusiast market. Beyond the gaming and multimedia segments, graphics cards have been increasingly used for general-purpose computing , such as big data processing. The growth of cryptocurrency has placed a severely high demand on high-end graphics cards, especially in large quantities, due to their advantages in the process of cryptocurrency mining. In January 2018, mid- to high-end graphics cards experienced

7776-552: The graphics card simultaneously to feed separate displays. The main advantages of integrated graphics are: a low cost, compactness, simplicity, and low energy consumption. Integrated graphics often have less performance than a graphics card because the graphics processing unit inside integrated graphics needs to share system resources with the CPU. On the other hand, a graphics card has a separate random access memory (RAM), cooling system, and dedicated power regulators. A graphics card can offload work and reduce memory-bus-contention from

7884-484: The graphics card. It may contain information on the memory and memory timing, operating speeds and voltages of the graphics processor, and other details which can sometimes be changed. Modern Video BIOSes do not support full functionalities of graphics cards; they are only sufficient to identify and initialize the card to display one of a few frame buffer or text display modes. It does not support YUV to RGB translation, video scaling, pixel copying, compositing or any of

7992-464: The height of a PCIe slot, some can be as low as "half-height". Length and thickness can vary greatly, with high-end cards usually occupying two or three expansion slots, and with modern high-end graphics cards such as the RTX 4090 exceeding 300mm in length. A lower profile card is preferred when trying to fit multiple cards or if graphics cards run into clearance issues with other motherboard components like

8100-460: The image colors to 256, every pixel needs only 8 bits, or 1 byte each, so the example image now needs only 640×480×1 = 307,200 bytes (300 KiB), plus 256×3 = 768 additional bytes to store the palette map in itself (assuming RGB), approximately one third of the original size. Smaller palettes (4-bit 16 colors, 2-bit 4 colors) can pack the pixels even more (to one sixth or one twelfth), obviously at cost of color accuracy. Indexed color

8208-404: The image using color quantization . Such a palette is frequently insufficient to represent the image accurately; difficult-to-reproduce features such as gradients will appear blocky or as strips ( color banding ). In those cases, it is usual to employ dithering , which mixes different-colored pixels in patterns, exploiting the tendency of human vision to blur nearby pixels together, giving

8316-463: The images in smaller files. Interesting colorized and artistic effects can be easily achieved by altering the color palette of indexed color images, for example to produce colorized sepia tone images. Due to the separate nature of the associated palette element of the indexed color images, they are ideal to remap grayscale images into false color ones through the use of false color palettes . Simple video overlay can be achieved easily through

8424-404: The index number 0, but other may be chosen if the overlay is performed by software . At design time, the transparent color palette entry is assigned to an arbitrary (usually distinctive) color. In the example below, a typical arrow pointer for a pointing device is designed over an orange background, so here the orange areas denoted the transparent areas (left). At runtime , the overlapped image

8532-798: The industry. AMD and Intel being direct competitors in the CPU industry is also noteworthy, since AMD-based graphics cards may be used in computers with Intel CPUs. Intel's integrated graphics may weaken AMD, in which the latter derives a significant portion of its revenue from its APUs . As of the second quarter of 2013, there were 52 AIB suppliers. These AIB suppliers may market graphics cards under their own brands, produce graphics cards for private label brands, or produce graphics cards for computer manufacturers. Some AIB suppliers such as MSI build both AMD-based and Nvidia-based graphics cards. Others, such as EVGA , build only Nvidia-based graphics cards, while XFX , now builds only AMD-based graphics cards. Several AIB suppliers are also motherboard suppliers. Most of

8640-459: The largest AIB suppliers are based in Taiwan and they include ASUS , MSI , GIGABYTE , and Palit . Hong Kong–based AIB manufacturers include Sapphire and Zotac . Sapphire and Zotac also sell graphics cards exclusively for AMD and Nvidia GPUs respectively. Graphics card shipments peaked at a total of 114 million in 1999. By contrast, they totaled 14.5 million units in the third quarter of 2013,

8748-409: The least-used color in the system palette (generally, one used by another window in the background) and substitutes it with the new color. Due to there being limited room for colors in the system palette, the algorithm also tries to remap similar colors together and will always avoid creating redundant colors. The final result depends on how many applications are trying to show their colors on screen at

8856-487: The like were generally replaced in the mid 1980s by the more flexible RGB color model , in which a given color can be obtained by mixing different amounts of the three primary colors red, green, and blue. Although the total number of different colors depends on the number of levels per primary, and on a given hardware implementation (a 9-bit RGB provides 512 combinations, a 12-bit RGB provides 4,096, and so on), in this model digital-to-analog converters (DAC) can generate

8964-435: The limited range of colors used for every image, and how many palette entries are left unused. Many indexed color display devices do not reach the 24-bit limit for the full RGB palette. The VGA for IBM PC compatibles, for example, only provides an 18-bit RGB palette with 262,144 different possible colors in both 16- and 256- indexed color graphic modes. Some image editing software allows gamma correction to be applied to

9072-454: The master palette (after dumping this into the hardware color registers), and writes the result in the video buffer. Here is a sample of a simple mosaic of the four image thumbnails using a master palette of 240 RGB arranged colors plus 16 additional intermediate shades of gray; all images are put together without a significant loss of color accuracy: When using indexed color techniques, real life images are represented with better fidelity to

9180-409: The multimedia experience. Within the graphics industry, these products are often referred to as graphics add-in boards (AIBs). The term "AIB" emphasizes the modular nature of these components, as they are typically added to a computer's motherboard to enhance its graphical capabilities. The evolution from the early days of separate 2D and 3D cards to today’s integrated and multifunctional GPUs reflects

9288-496: The multitude of other 2D and 3D features of the graphics card, which must be accessed by software drivers. The memory capacity of most modern graphics cards ranges from 2 to 24 GB . But with up to 32 GB as of the last 2010s, the applications for graphics use are becoming more powerful and widespread. Since video memory needs to be accessed by the GPU and the display circuitry, it often uses special high-speed or multi-port memory, such as VRAM , WRAM , SGRAM , etc. Around 2003,

9396-426: The ongoing technological advancements and the increasing demand for high-quality visual and multimedia experiences in computing. As an alternative to the use of a graphics card, video hardware can be integrated into the motherboard , CPU , or a system-on-chip as integrated graphics. Motherboard-based implementations are sometimes called "on-board video". Some motherboards support using both integrated graphics and

9504-511: The operating system or an extra software package may provide certain programming APIs for applications to perform 3D rendering. Some GPUs are designed with specific usage in mind: As of 2016, the primary suppliers of the GPUs (graphics chips or chipsets) used in graphics cards are AMD and Nvidia. In the third quarter of 2013, AMD had a 35.5% market share while Nvidia had 64.5%, according to Jon Peddie Research. In economics, this industry structure

9612-491: The original up to an acceptable level. Indexed color images are heavily dependent on their own color palettes. Except for a few well known fixed-color palettes (such as that of the Color Graphics Adapter —CGA), raw image data and/or color map tables cannot be reliably exchanged between different image files without some kind of intermediate mapping. Also, if the original color palette for a given indexed image

9720-406: The output is effectively made, the program must realize its logical palette: The system tries to match the "logical" colors with "physical" ones. If an intended color is already present in the system palette, the system internally maps the logical to the system palette indexes (because they rarely coincide). If the intended color is not present yet, the system applies an internal algorithm to discard

9828-482: The palette for reserved colors, color indices that the program could use for special purposes. It is more general to use only 6R×6G×6B = 216 (as in the Web colors case), 6R×8G×5B = 240 or 6R×7G×6B = 252 , which leaves room for some reserved colors. Then, when loading the mosaic of image thumbnails (or other heterogeneous images), the program simply maps every original indexed color pixel to its most approximated in

9936-537: The people writing graphics programs. A pixel's bits in indexed-color, all-pixel-addressable images are not always contiguous in video memory or image files (i.e., chunky organization is not always used.) Some video hardware, such as the 16-color graphic modes of the Enhanced Graphics Adapter (EGA) and Video Graphics Array (VGA) for IBM PC compatibles or the Amiga video buffer are arranged as

10044-407: The picture quality can degrade depending on cable quality and length. The extent of quality difference depends on the individual's eyesight and the display; when using a DVI or HDMI connection, especially on larger sized LCD/LED monitors or TVs, quality degradation, if present, is prominently visible. Blu-ray playback at 1080p is possible via the VGA analog interface, if Image Constraint Token (ICT)

10152-475: The pixel data given the limited amount of video memory . Instead, they used a colour look-up table (CLUT) where each pixel's data pointed to an entry in the CLUT, and the CLUT was set up under program control. This meant that the image CLUT data had to be stored along with the raw image data in order to be able to re-produce the image correctly. Hardware palettes based on component video colors such as YPbPr or

10260-406: The realm of IBM PC compatibles, the early standards included Monochrome Display Adapter (MDA) , Color Graphics Adapter (CGA) , Hercules Graphics Card , Enhanced Graphics Adapter (EGA) , and Video Graphics Array (VGA) . Each of these standards represented a step forward in the ability of computers to display more colors, higher resolutions, and richer graphical interfaces, laying the foundation for

10368-427: The same time in the hardware color registers. A solution is to use a unique, common master palette or universal palette , which can be used to display with reasonable accuracy any kind of image. This is done by selecting colors in such way that the master palette comprises a full RGB color space "in miniature", limiting the possible levels that the red, green, and blue components may have. This kind of arrangement

10476-405: The same time. The foreground window is always favored, so background windows may behave in different ways: from become corrupted to quickly redraw themselves. When the system palette changes, the system triggers a specific event to inform every application. When received, a window can quickly redraw itself using a single Win32 API function. But this must be done explicitly in the program code; hence

10584-422: The skills of the color-forcing program and the behavior of the other programs (although this problem is the same as in the regular case), and that of the operating system itself. Graphics card Display via one of: A graphics card (also called a video card , display card , graphics accelerator , graphics adapter , VGA card/VGA , video adapter , display adapter , or colloquially GPU )

10692-531: The total number of colors in an image is equal to or less than 256. When using RGB, the TIFF and PNG file formats can optionally store the RGB triplets with a precision of 16-bit (65,536 levels per component) yielding a total of 48 bits per pixel. A proposed extension to the TIFF Standard allows non-RGB color palettes, but this was never implemented in software due to technical reasons. The color map table of

10800-488: The trademark Accelerated Processing Unit (APU), while Intel brands similar technology under " Intel Graphics Technology ". As the processing power of graphics cards increased, so did their demand for electrical power. Current high-performance graphics cards tend to consume large amounts of power. For example, the thermal design power (TDP) for the GeForce Titan RTX is 280 watts . When tested with video games,

10908-411: The transparent palette entry number is defined by the hardware, and it used to be the number 0. Some indexed color image file formats as GIF natively support the designation of a given palette entry as transparent , freely selectable among any of the palette entries used for a given image. The BMP file format reserves space for Alpha channel values in its Color Table, however currently this space

11016-525: The use of a separate 2D graphics card in tandem. The Voodoo's architecture marked a major shift in graphical computing by offloading the demanding task of 3D rendering from the CPU to the GPU, significantly improving gaming performance and graphical realism. The development of fully integrated GPUs that could handle both 2D and 3D rendering came with the introduction of the NVIDIA RIVA 128 . Released in 1997,

11124-485: The user designated background color as the transparent color when performing cut, copy, and paste operations. Although related (due to they are used for the same purposes), image bit masks and alpha channels are techniques which do not involve the use of palettes nor transparent color at all, but off-image added extra binary data layers. Microsoft Windows applications manage the palette of 4-bit or 8-bit indexed color display devices through specialized functions of

11232-452: The video frame buffer described in 1975 by Kajiya, Sutherland, and Cheadle. These supported a palette of 256 RGB colors. SuperPaint used a shift-register frame buffer, while the Kajiya et al. system used a random-access frame buffer. A few earlier systems used 3-bit color, but typically treated the bits as independent red, green, and blue on/off bits rather than jointly as an index into

11340-674: The video memory was typically based on DDR technology. During and after that year, manufacturers moved towards DDR2 , GDDR3 , GDDR4 , GDDR5 , GDDR5X , and GDDR6 . The effective memory clock rate in modern cards is generally between 2 and 15  GHz . Video memory may be used for storing other data as well as the screen image, such as the Z-buffer , which manages the depth coordinates in 3D graphics , as well as textures , vertex buffers , and compiled shader programs . The RAMDAC , or random-access-memory digital-to-analog converter, converts digital signals to analog signals for use by

11448-457: The whole 24 bit color space, each being assigned an 8 bit index. This way, while the system can potentially reproduce any color in the RGB color space (as long as the 256 color restriction allows), the storage requirement per pixel is lowered from 24 to 8 bits per pixel. In an application showing many different image thumbnails in a mosaic on screen, the program may not be able to load all the adaptive palettes of every displayed image thumbnail at

11556-421: Was a continuous image with decreased vertical resolution that would increase to full resolution over a few seconds as the later parts of the image data arrived. Indexed color saves a lot of memory, storage space, and transmission time: using truecolor , each pixel needs 24 bits, or 3 bytes. A typical 640×480 VGA resolution truecolor uncompressed image needs 640×480×3 = 921,600 bytes (900 KiB). Limiting

11664-418: Was widely used in early personal computers and display adapters' hardware to reduce costs (mainly by requiring fewer of the then-expensive RAM chips ) but also for convenient image management with limited-power CPUs (of the order of 4 to 8 MHz ), file storage ( cassette tapes and low density floppy disks ). Notable computer graphics systems extensively (or even exclusively) using pseudocolor palettes in

#818181