Which graphic file format is not raster. What are the graphic file formats

BMP (Windows device independent bitmap)

Native Windows format. It is supported by all graphic editors running under this operating system. It is used to store bitmaps intended for use in Windows, and this is where its scope ends. Using BMP for something other than Windows is a fairly common mistake.

gif(CompuServe Graphics Interchange Format)

independent of hardware The GIF format was developed in 1987 (GlF87a) by CompuServe for transmitting bitmap images over networks. In 1989, the format was modified (GIF89a) to add transparency and animation support. GIF uses LZW compression, which allows you to compress files with a lot of uniform fills (logos, inscriptions, diagrams) quite well.

JPEG(Joint Photographic Experts Group)

Strictly speaking, JPEG "om is not a format, but a compression algorithm based not on searching for identical elements, but on the difference between pixels. The higher the compression level, the more data is discarded, the lower the quality. Using JPEG, you can get a file 1,500 times smaller than BMP! Initially, there was no CMYK in the format specifications, Adobe added support for color separations, but CMYK JPEG causes problems in many programs. JPEG "compresses photographic quality bitmaps better than logos or schemes.

TIFF, TIFF(Target Image File Format)

The hardware-independent TIFF format, one of the most widespread and reliable today, is supported by almost all PC and Macintosh programs in one way or another related to graphics. It has a full range of color models available from monochrome to RGB, CMYK and optional Pine Colors. TIFF can contain clipping paths, alpha channels, layers, and other additional data. In the TIFF format, it is possible to save using several types of compression: JPEG, ZIP, but, as a rule, only LZW compression is used.

EPS(Encapsulated PostScript)

The format uses a simplified version of PostScript: it cannot contain more than one page in one file, it does not save a number of settings for the printer. EPS is designed to transfer vectors and raster to publishing systems, it is created by almost all programs that work with graphics. It only makes sense to use it when the output is on a PostScript device. EPS supports all the necessary printing color models. EPS has many varieties, depending on the program of the creator. The most reliable EPS programs are produced by Adobe Systems: Photoshop, Illustrator, InDesign.

QXD(QuarkXPress Document)

The working format of the well-known QuarkXPress layout program. The package is stable, fast and easy to use. The main, and not defeated competitor of Adobe Systems, continues to exist now in the fifth reincarnation. It should also be noted that two previous versions of QuarkXPress 3.x and QuarkXPress 4.x are still in use. The special ideology of the package lies in its ability to adapt to any tasks of the layout designer. After all, the main functions are performed special extensions(Xtensions), of which there are more than Plugins for Photoshop.

RM(page maker)

Adobe Systems layout program format. An extremely simple package in terms of features. It was intended primarily for the transition from a manual type of layout to a computer one with minimal costs for staff training. We received distribution due to timely Russification and, again, ease of development for beginners. Currently, the development of the package is stopped.

ID(InDesign)

Code name “Quark Killer” Follower of RM, designed to oust competitors in the publishing market, primarily Quark. The collective hodgepodge of solutions borrowed from other layout packages did not lead to the expected result. ID is an extremely clumsy and inconvenient package that turned out to be the killer only of its progenitor RM, and then because of the cessation of the development of the latter. The advantages include only a built-in PostScript interpreter and apparent super compatibility with other Adobe products.

PDF(Portable Document Format)

Proposed by Adobe as a platform-independent format for creating electronic documentation, presentations, transferring layouts and graphics over networks. PDF files are created by converting from PostScript files or by the export function of a number of programs. The format was originally designed as a means of storing electronic documentation. Therefore, all data in it can be compressed, and in different ways: JPEG, RLE, CCITT, ZIP. The PDF can also retain all of the output device information that was in the original PostScript file.

APS(Adobe PostScript, page description language)

It was created in the 80s to implement the WYSIWYG (What You See is What You Get) principle. Files of this format are actually a program with commands to execute for the output device. These files contain the document itself, related files, fonts used, as well as other information: color separation boards, additional boards, raster lineature and halftone dot shape for each board, and other data for the output device. Data in a PostScript file is usually written in binary encoding (Binary). binary code takes up half the space of ASCII.

CDR(format of the popular vector editor CorelDraw)

The package gained its popularity and distribution due to its apparent ease of use and interactive special effects (lenses, transparencies, non-standard gradients, etc.). The broad possibilities of this program, in terms of effects, are explained by a richer internal page description language than Adobe products that use PostScript. This is precisely the main disadvantage of CorelDraw. PostScript with Corel special effects is often a headache for printers and prepress bureaus.

CCX(vector graphics format from Corel)

Except Corel Draw nothing is supported. Not suitable for printing and the Internet. The advantages include only a small amount of files saved in this format and the presence of many excellent clipart.

Journal “Computer practice. Manual for professionals” №1

P.S. Of course, the log forgot about common files like:

PNG(Portable Network Graphics) is a raster format for storing graphic information using lossless compression. PNG was created both to improve and replace the format gif graphic format that does not require a license to use.

ICO(Windows icon) - storage format for file icons in Microsoft Windows, similar to the CUR (Windows cursors) format.

AI(Adobe Illustrator) is a vector graphics editor developed and distributed by Adobe Systems.

DjVu(French déjà vu - “already seen”) is a lossy image compression technology and format designed specifically for storing scanned documents.

We all know that absolutely all files have their own specific extension. Photos - jpg, music files- mp3 and so on. The file name can be whatever the user wants, and it is not recommended to change the extension in the file. Sometimes changing the extension can corrupt the file. So be careful about this. Let's look at the most popular file extensions that we see almost every day:

Archive extensions:

ZIP is a file using ZIP compression, which is supported by almost all archivers.

RAR (Roshal ARchive) is already a file using RAR compression. The compression ratio is much higher than in ZIP compression.

Video extensions:

AVI- one of the most popular extensions video files. The compression ratio is less than similar video formats. This format is played in almost all video players.

MPEG1-2(MPG)– lossy audio and video storage extension.

MPEG4(MP4)- This format is very often used to transfer a file on the Internet.

Graphic extensions:

GIF (Graphics Interchange Format) format for network distribution. The files are very small. Supports animation.

BMP- raster format. The most common graphic format on Windows. Almost all graphics programs can create and read BMP format. The standard graphics file format for Windows. Almost all editing programs windows images can create and read BMP files. An image with a .BMP extension cannot be compressed.

JPEG(JPG)- very often used for raster images (drawings, photos). Excellent compression ratio allows you to reduce the size. But I would like to note that when compressing a file, the quality of the compressed image may be lost. The JPEG format is one of the best formats in the field of photographs and images, as it supports a large number of colors. (16.7 million colors)

PSD (Photo Shop Data)- Photoshop processing format.

TIFF(Tagged Image File Format)- very widely used by users digital technology. It is compressed without data loss, which is a big plus over other formats. The number of colors is about the same as JPEG format- 16.7 million colors.

Document formats:

DOC- I think it's the best known format🙂 Owned by the program Microsoft Word. Contains both text and graphics, pictures, tables, charts, etc.

PDF (Portable Document Format)– This format belongs to an equally well-known program – Adobe Acrobat. It is mainly intended for the presentation of printed products in electronic form. To display this format, the free Adobe Reader program is used.

TXT– a document containing unformatted text. On Windows, it is created and opened with regular notepad.

Music formats:

MP3- The compression ratio is about the same as that of the JPG format. But naturally, with strong compression, the sound quality deteriorates significantly.

WAV- a format from Microsoft, which is used in Windows. Since this format has large file sizes, it is very inconvenient for transmission over the Internet.

WMA( Windows Media audio)- another music format from Microsoft for storing audio information. It has good ratio compression.

Which store any type of persistent graphic data ("images") intended for subsequent rendering. The ways in which these files are organized are called graphic formats. After writing to a file, the image ceases to be the actual image - it turns into digital data. The format of this data may change as a result of file conversion operations. Depending on the nature of the supported graphics, file formats are classified into one of the following types: raster format, vector format, metafile format. The most common graphic formats:

AI (Adobe Illustrator, Adobe AI) is a metafile format developed by Adobe for Macintosh, Microsoft Windows, NeXT; used to record and store heterogeneous types of images, including drawings, drawings and decorative inscriptions.

PSD (Photoshop Document, Adobe Photoshop, Adobe PSD) is a raster format that is part of the graphic Photoshop editor by Adobe; used by publishing systems on PC and Macintosh platforms. PSD allows you to record with or without compression (RLE) an image with many layers, masks, additional channels, outlines, and other graphic elements.

ART is a format developed by Gonson-Grace for storing photographs and drawings.

AutoCAD DXF (Drawing Interchange Format) and AutoCAD DXB (Drawing Interchange Binary) are two versions of the same format (without data compression) developed and maintained by Autodesk for the AutoCAD CAD program running on the MS-DOS platform. DXB is a simplified (binary) version of the seven-bit DXF. In addition to AutoCAD, the format is supported by many CAD programs, CorelDRAW and others, in particular, for the exchange of data of different types: vector-oriented data, texts, three-dimensional drawings. However, a number of programs claiming to support DXF import only implement some of its features. DXF changes with each version of AutoCAD. The DXF and DXB filenames use *.dxf, *.dxb, *.sld, *.adi extensions.

BDF (Bitmap Distribution Format) is a bitmap format developed by the X Consortium for exchanging bitmap font data between the X Window and other systems. There is no compression, the maximum image size is not limited, the color is monochrome. Each BDF file stores data for only one typeface (a group of fonts under a single name).

BMP is a bitmap format developed by Microsoft for Windows OS; supported by all graphics editors running under its control, capable of storing both indexed (up to 256 colors) and RGB color (16.7 million shades). Most BMP files are stored uncompressed.

CDR (CorelDRAW Document) is a vector format originally known for poor file stability and file compatibility. Many PC programs (FreeHand, Illustrator, PageMaker) can import CDR files. Starting with the seventh version, CorelDRAW in CDR files compression is applied separately for vector and raster graphics; fonts can be embedded.

CGM (Computer Graphics Metafile) - standard (ANSI and ISO) and metafile display format vector images on the Web, adopted in late 1998 by the 3WC (WWW Consortium). The format is designed to support a variety of graphic images, including art graphics, technical illustrations, cartography, computer publishing systems. Although CGM contains many graphics primitives and attributes, it is less complex than PostScript, allows for smaller files, and supports the exchange of complex and high-quality artistic images. The format uses different types compression (RLE, CCITT Group 3 and Group 4); the color palette is not limited. One CGM file can contain multiple images.

CPT is a raster format in Corel PHOTO-PAINT that stores full-color images and vector objects.

DPX (Digital Picture Exchange Format; aka SMPTE Digital Picture Exchange Format) is a raster format designed to store a single movie frame or video data stream; developed by Kodak Cineon, adopted by ANSI and the Society of Motion Picture and Television Engineers (SMPTE) with minor changes as a standard. The format is supported by Kodak software.

DWG is a vector format of the Autodesk AutoCAD program for storing drawings.

EMF (Enhanced Metafile) is a metafile format developed by Microsoft for storing images as a sequence of commands that cause images to be displayed. In November 2005, a vulnerability in EMF and WMF formats from "buffer overflow attacks" was discovered, and at the end of December, a family of Internet worms appeared. The infection occurred when users visited a number of sites that used a WMF vulnerability to download Trojans to a remote machine. Soon, stand-alone versions of viruses spread as mail worms appeared in attached image files. Microsoft has responded to this threat with the release of Security Advisory 912840 and (January 11, 2005) a hotfix for Windows XP, Windows 2000 (Service Pack 4), Windows Server 2003.

3DS (3D Studio, ASC) - a format developed by Autodesk, a tool 3D modeling("description of the scene"); also used as an interchange format. The format provides optimal distribution of resources on the PC platform, supports all colors without limitation, has no compression. Many 3D modeling programs read and write files in this format. Strictly speaking, 3DS are two formats that are used as exchange formats - binary with *.3ds extension and text with *.asc extension.

EPS (Encapsulated PostScript, EPSF) - a simplified version of the PostScript format (PDL), developed by Adobe as a vector format, later its raster version appeared - Photoshop EPS. The EPS format cannot contain more than one page in a single file and does not store a number of printer settings. As with PostScript print files, EPS format record the final version of the work, although programs such as Adobe Illustrator, Photoshop and Macromedia FreeHand can use it as a working tool.

FH8 (FreeHand Document) is the eighth version of the FH format, designed for Macintosh PCs only. FreeHand itself, Illustrator 7, and a limited number of programs from Macromedia can work with it. Starting with the seventh version, the FH format has full cross-platform compatibility, however, some FreeHand effects are incompatible with PostScript.

FIF (Fractal Image Format) - a format developed by Iterated Systems, used for storing photographs and on the Internet, supports own system FIF compression.

FITS (Flexible Image Transport System, FTI) is a raster format and image storage standard used by many organizations (including scientific organizations, government bodies) to store astronomical (obtained by orbiters) and terrestrial images (in particular, radio astronomy data and digitized photographic images) . The format is widely used for data exchange between various hardware platforms and software applications that do not support a common file format. FITS is considered sufficient simple format uncompressed with "unlimited" grayscale. It can store many types of data, including raster, ASCII text, multidimensional matrices, binary tables.

GIF (Graphics Interchange Format) - a standard raster format for representing images on the WWW; was developed in 1987 by CompuServe, overshadowing the older PCX and MacPaint formats. Main advantages: the ability to use on many platforms and the availability of an efficient 12-bit LZW compression algorithm with free (until 1994) implementations. The format allows you to well compress files that have a lot of uniform fills (logos, inscriptions, diagrams), record the image “through the line” (Interlaced mode), so that, having only part of the file, you can see the entire image, but with a lower resolution (GIF supports resolution up to 66536x65536).

IFF (Interchange File Format), ILM, ILBM, LBM (InterLeaved BitMap), Amiga Paint - family bitmap formats developed and maintained for MS-DOS, UNIX, Amiga platforms by Electronics Arts and Commodore-Amiga. Distinctive feature IFF is its versatility: it can be used not only to support graphics, but also sound on all platforms except the Amiga. IFF was previously known as the 24-bit format for MS-DOS, but has since been replaced by TIFF formats and TGA, and then the JFIF format. Some characteristics of the IFF format: maximum image size of 64K by 64K pixels; used in uncompressed and RLE compression variants, supports colors from 1- to 24-bit; the format of the numbers "senior in the minor", has a specification on the CD; when used with MS-DOS and UNIX, filenames can have *.iff and *.lbm extensions.

JFIF (JPEG File Interchange Format), JFI, JPG, JPEG - C-Cube Microsystems' bitmap format is the most widely used, so most "JPEG" images would be more correctly called "JFIF". Using JFIF, it is recommended to save only the final version of the work, since each intermediate save leads to data loss and distortion of the original image.

PCX (PC Paintbrush File Format) is one of the most common raster formats; designed to store illustrations in desktop publishing systems. The format was developed by Zsoft for the Paintbrush program, after the conclusion of an OEM agreement with Microsoft Corporation, it began to be used in various systems that work with graphics. Main features: maximum image size 64K by 64K; 24-bit color support; uses RLE compression (may work without compression); supports CD-ROM. Versions of the PCX format are DCX and PCC, whose filenames have the appropriate extension.

PDF (Portable Document Format) is a metafile format proposed by Adobe for graphic files (vector and raster) containing illustrations and text with a large set of fonts and hypertext links in order to transmit them over the network in a compressed form.

PDS (Planetary Data System Format) - NASA's standard format for storing data collected by spacecraft and ground-based observations about the Sun, Moon and planets; is also used by other organizations to store similar data. The basis of the format is the object description language - ODL (Object Description Language). The maximum image size and colors in PDS format are unlimited; supported by all platforms.

PGML (Precision Graphics Mark-up Language) is a vector format that describes graphics in terms of mathematical formulas, rather than raster pixels, which saves disk space and the ability to scale an image without losing its resolution and other quality indicators. The format was submitted to the W3C consortium (WWW Consortium) as a network standard by Adobe Systems, IBM, Netscape, Sun Macromedia; used on the Internet.

Photo-CD (PCD, Kodak Photo CD) is a bitmap format developed by Eastman Kodak and designed to store and reproduce full-color images (usually photographs) recorded at various resolutions on CDs. Format Supported Photo programs CD ACCess, Photoshop, Shoebjx. The Photo CD format supports 24-bit colors, has its own compression system, the maximum image size is 2048x3072 pixels, allows you to store only one image in a file, uses the RLE and JPEG compression systems (in the DCT version). Kodak does not disclose more details.

PIC (Pictor PC Paint, PC Paint) - a bitmap format developed by Paul Mace for drawing programs on the MS-DOS platform, is a hardware-dependent format created to meet the requirements graphics adapters IBM family (CGA, EGA, VGA). The PIC format is similar to the PCX format, the *.pic and *.clp extensions are used in the file name.

PICT (Macintosh QuickDraw Picture Format) is a Macintosh clipboard standard that supports both bitmap and vector graphics. On a Macintosh PC, PICT works with all programs. On a PC, it is read by a number of programs, but working with it is rarely easy. PICT file names have the extension *.pic or *.pct.

PNG (Portable Network Graphics) is a raster format approved as a standard by the W3C (WWW Consortium) and designed to replace GIF. The format provides indexing of up to 256 colors, support for 24-bit and 48-bit color representation (True Color) and the implementation of a transparency channel (the so-called alpha channel). Algorithm for dynamic image compression without Loss PNG 10-30% more efficient than this type of compression implemented in GIF format.

PS (PostScript) - PostScript page description language format (aka - control language laser printers) was developed in 1984 by Adobe. The format is used to provide printing and storage of fonts, as well as to exchange documents formatted by it. The advantage of the PS format is that it uses an independent specific devices playback system (including printer or screen type).

RAF (RAW) is a bitmap format used in digital cameras that maintains the image exactly as it was captured by the camera's sensor. Using this format eliminates artifacts associated with image pre-processing by camera software (for example, when it is JPEG-compressed) and provides the photographer with the ability to post-process photographs (correct exposure, change color balance, increase size).

Scitex CT is a raster format developed by Scitex; differs slightly from TIFF, with the exception of one feature: on Scitex Dolev phototypesetters, files of this format are displayed somewhat faster. On PC, filenames in Scitex CT format have the *.sct extension.

swf( Shockwave Flash) is an internal vector format of the Macromedia Flash program, used for animation on the Internet.

TGA (TrueVision Targa) - Truevision's format, developed for color television, supports RLE compression, file names have *.tga extension.

TIFF (TIF, Tagged Image File Format) is a raster format developed by Aldus Corporation, originally intended for large graphic images. high resolution obtained by scanning. The format is characterized by high quality of transmission and color preservation of original images. In the future, the format was adapted for professional graphics packages and expanded.

WMF (Windows Metafile, Microsoft Windows Metafile) is a metafile format created for use with Windows OS, used to transfer vectors via the clipboard. WMF is supported by almost all programs running under Windows and in one way or another related to vector graphics. Despite the seeming simplicity and versatility, it is recommended to use the WMF format only in extreme cases to transfer the so-called bare vectors. WMF distorts color, does not save a number of parameters that can be assigned to objects in various vector editors, and is not understood by programs oriented to the Macintosh PC. WMF files use the *.wmf extension.

VML (Vector Mark-up Language) - a vector format that was submitted to the W3C consortium by Microsoft, Hewlett-Packard, Autodesk, Macromedia, Visio; used on the Internet.

It was last Friday, but the Friday post under N3 could not be written. The reason is banal - the lack of free time in connection with the housing issue and a number of other problems. But, this Friday the photo will be for sure. It already exists and was ready for publication yesterday, but nevertheless I decided to spend my free evening time on repair work in the apartment. Therefore, if you have not watched, then be sure to look and - cheer yourself up.

Let's return to the topic of the post, or rather to the question of what picture formats happen? general word "picture" I don't like photography. But this is how this question sounds very often, so I decided to leave everything unchanged. I'll just add one clarification. Since a photo is a bitmap, so in a post we will talk only about raster image formats.

Generally graphic formats- a set of rules for processing the received graphic data, for the purpose of their further storage or editing. As they say in the lines of V. Mayakovsky “All professions are needed, all professions are important”... The same can be attributed to image formats.

Developers offer a lot bitmap formats for storing files. Among the most commonly used are the following: BMP, TIFF, GIF, JPEG, PNG, PSD, ICO.So, consider some of the pros and cons, as well as the scope of the listed raster image formats.

Bitmap formats

• BMP-(abbreviation for Bit Map image) represents standard bitmap format and has a universal purpose. It is supported by most graphics editors, including the fairly common Paint. Initially, coding in it was performed by the most in a simple way, on . But this turned out to be uneconomical, since each pixel was represented by only one byte. Consequently, only 256 colors became available, which severely limited the ability to transmit images. In the future, he improved somewhat. Bitmap image almost optimal for storing data and sharing it with other similar applications. But, at the same time, it takes up too much memory space, since it is necessary to save the coding of all points of the image. File BMP does not support animation and interlaced display.
• TIFF— (from Tagged Image File Format)– universal for publishing systems and topographic graphics. Such bitmap formats provide high quality print. They were created to support almost all programs designed to work with bitmap files, so they are compatible with all platforms. widely used TIFF in printing and publishing. Files (scanned images, illustrations, faxes, etc.) with the extension .tif in that powerful format stored for further color printing, although monochrome printouts are also available - in views CMYK and RGB. It is not used for publishing pictures on a computer network or when creating websites, because it is quite large. It is also unsuitable for animation.
• gif— (by first letters from Graphic Interchamge Format)serves to storebitmaps in graphicsand to share them. He is one of the "oldest" on the Internet, has already been in circulation. long time, even though it uses indexed colors (in a limited set). Files with extension.gifwidely used in the design of Web sites. Among the main advantagesGraphic Interchamge Format it is worth mentioning that the appearance of the image does not depend on the underlying platform or on the type of browser, and compression occurs without loss of information. High-quality images with a small amount of uniform colors, drawings, transparent pictures and animation are displayed in this format.gifsmall in size, so it loads quickly, which is important when creating HTML pages. However, the format is significant disadvantage- it has a small set of colors, which limits its ability to store images that have smooth transitions.
• JPEG— (abbreviation for Joint Photographic Expert Group) helps to get rid of the flaws that arise when creating and saving images in GIF. It uses a method of compressing photographs or other pictures. These raster graphics file formats are the most common when storing multi-color pictures. Image compression (they are stored in files marked .jpg). is performed in a smooth mode, which ensures its high degree and reduces data loss. On the hard drive in JPEG it is convenient to save a significant number of pictures, in particular, large photographs with smooth transitions. This saves a lot of disk space. Also using JPEG available to publish acceptable quality photo in a computer network. But it should be borne in mind that during compression, part of the data is lost, and when the same image is saved again, the chances of irreversible loss of information increase. In this regard, the improved version of the format greatly improves the situation - JPEG 2000. True, it is not supported by all browsers, which slows down its distribution.
• PNG— (portable network graphics) allows you to store raster graphics in lossless compressed form, and the files are smaller in volume than in GIF. In the format PNG almost any color is available, as well as transparency. This circumstance opens up wide possibilities in web design. Now it is constantly popular because it fits with all platforms, supports interlaced display, has a significant color gamut, and supports animation.
• Internal PSD bitmap formats (short for PhotoShop Document) intended for program packages. They support all types of images, as well as their layers during processing. Saved in files marked with an extension .psd.

There are others raster graphics formats, which were not discussed in the article, but you can write about them in the comments, while not forgetting about the contest!

• introduce students to the basic formats of raster images;
• introduce the possibility of converting formats;
• teach how to choose the optimal parameters when scanning images.

Transferring images from one program to another is the same throughout the diverse world of digital imaging, as each program has its strengths and weaknesses. weaknesses. To take advantage of the software's strengths, images must be exported quickly and efficiently. To streamline this process, software developers have created views computer files- formats.

There are many different graphic file formats. In order to be able to solve the problems of transferring images from one program to another and compressing them in order to save disk space, as well as to find the optimally suitable graphic format for further image processing, let's get acquainted with some of the most common ones.

Native file formats

Native format - usually a proprietary format created specifically for software application. In most programs, this format is the most efficient means of saving files during editing, but is not portable (or partially portable) to other applications.

The "native" format for CorelDRAW is CDR, which is most often used. For Microsoft Word, the native format is DOC, for Adobe Flash it is FLA, and so on. Adobe editor Photoshop's native format is PSD, in which you can save not only graphic information, but also layers and channels. Adobe Photoshop is undoubtedly the most famous image editing tool in the world. The popularity of Photoshop forced other graphics programs to support the PSD format so that artists could export and import files into Photoshop without having to first convert them to a commonly available file format.

There is a large number standard formats raster graphics. Consider only the most common of them.

BITMAP

BITMAP (bitmap) is one of the first raster formats. The format is distinguished by a very large file size, since data is recorded for each pixel separately. He is extremely simple structure and serves to describe and visualize small pictogram images (icons) widely used in graphic Windows interfaces and is also used in multimedia presentations.

There are several variations of this format. We are most familiar with the *.bmp extension, which supports data up to 24 b/p.

gif

The GIF (Graphics Interchange Format) raster format was developed by CompuServe Inc. in 1987 to provide compression for color bitmap files downloaded via telephone line and in computer networks.

The GIF format can only store color depth data from 1 to 8 b/p. GIF uses a very efficient archiver. The format is widely used on Web pages for images with a small number of colors (signs, logos, buttons, design elements). Also, multimedia programs allow you to insert images in GIF format.

Features of the format: the image is drawn from top to bottom with a change in clarity and detail (option - interlacing ( interlacing )), the format allows you to set a transparent area or define a transparent color, which allows you to place images on any background.

The possibilities of reducing the file size are not limited to compression, GIF allows you to arbitrarily set the size of the palette used in the image (other formats, as a rule, have only standard options color depth). The disadvantages of the format usually include a limited number of possible colors.

The format allows you to store a large number of images - frames, so you can consider GIF as an animation format.

JPEG

The JPEG format was created by the standards committee Joint Photographic Experts Group(Joint Photographic Experts Group) in 1987 to store photorealistic images - photographs. Based on the characteristics of human vision, this format uses lossy compression algorithms and provides a significant file reduction. JPEG compression called lossy - image data is lost when the file is compressed, which causes degradation of image quality.

The user has the ability to adjust the compression ratio (respectively, the quality level). If the user specifies high quality, less compression occurs. When the high compression setting is used, the file size is small, but image quality suffers more. Almost all programs, when saved in this format, allow you to preview the result to get a compromise between quality and file size.

The JPEG format supports color depths up to 24 b/p. Since the format has a very small file size, it has become very popular in Web publishing and image libraries in cases where a multi-color photorealistic image is required.

PNG

PNG format (Portable Network Graphics - portable network graphics) is specifically designed for placing graphics on Web pages. This format is young and combines the advantages of GIF and JPEG formats. It allows you to significantly compress the image file without quality loss, but it is not limited to a palette of 256 colors, it supports 8, 24 and 32 (24 b/p plus alpha channel) b/p.

This format uses a compression method in which information that is poorly perceived by the human eye is removed from the image. The compression ratio can be changed from low, when distortion is minimal, to high, when the image can undergo noticeable changes.

The PNG format does not support transparency, but it can include a single alpha channel that makes part of the image transparent in a browser that supports PNG channels. As with GIF, it provides a staged display with interlaced scanning.

TIFF

One of the most common bitmap formats used in preparing images for printing is TIFF (Target Image File Format), created by Aldus Corporation in 1986 to overcome the difficulties that arose when transferring graphic files from IBM-compatible computers to Macintosh and vice versa.

TIFF supports several compression schemes and special image manipulation features. LZW compression is a non-lossy data compression scheme - when a file is compressed, no data is destroyed and no degradation of quality should occur.

TIFF is today the standard file format supported by most graphic programs creating and processing images, as well as software packages layout. The format supports data up to 32 b/p. TIFF allows you to save an alpha channel with an image. In the latest versions of Adobe Photoshop, this format allows you to save documents with layers.

TIFF has become a common format for image capture systems from scanners, used in publishing systems. The format is portable between platforms and easily imported into all typesetting programs, making it indispensable when preparing documents for printing.