Examples of graphic file extensions. Raster graphics formats
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, but it is not recommended to change the file extension. Sometimes changing the extension can corrupt the file. So be careful about this. Let's look at the most popular file extensions that we come across almost every day:
Archive extensions:
ZIP is a file using ZIP compression, which is supported by almost all archivers.
RAR (Roshal ARchive)– this is already a file using RAR compression. The compression ratio is much higher than ZIP compression.
Video extensions:
AVI– one of the most popular video file extensions. The compression ratio is lower than that of similar video formats. This format is played in almost all video players.
MPEG1-2(MPG)– expansion of audio and video storage with data loss.
MPEG4(MP4)– this format is very often used to transfer files on the Internet.
Graphic extensions:
GIF (Graphics Interchange Format) - format for network distribution. The files are very small in size. Supports animation.
BMP – raster format. The most common graphics format in Windows. Almost all graphics programs can create and read the BMP format. 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 for downsizing. 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 digital technology users. It is compressed without data loss, which is a big advantage over other formats. The number of colors is approximately the same as the JPEG format - 16.7 million colors.
Document formats:
DOC– I think this is the most famous format :) Belongs to the Microsoft Word program. Contains both text and graphs, pictures, tables, diagrams, etc.
PDF (Portable Document Format)– This format belongs to at least famous program—Adobe Acrobat. Mainly intended for presentation in electronic form printing products. A free program is used to display this format. Adobe Reader.
TXT– a document containing unformatted text. In Windows, it is created and opened with regular notepad.
Music formats:
MP3– the compression ratio is approximately the same as that of the JPG format. But naturally, with strong compression, the sound quality deteriorates significantly.
WAV– a format from Microsoft that is used in Windows. Since this format has large sizes files, it is very inconvenient for transferring over the Internet.
WMA (Windows Media Audio)- another music format from Microsoft for storing audio information. Has a good compression ratio.
Which store any type of persistent graphical data (“images”) intended for subsequent visualization. The ways of organizing these files are called graphic formats. Once written to a file, the image ceases to be an image itself - 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 graphics supported, file formats fall 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 the Macintosh, Microsoft Windows,NeXT; used for recording and storing various types of images, including drawings, drawings and decorative inscriptions.
PSD (Photoshop Document, Adobe Photoshop, Adobe PSD) - a raster format included in the Adobe Photoshop graphics editor; 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, contours and other graphic elements.
ART is a format developed by Gonson-Grace, used 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 supported 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 data exchange different types: vector-oriented data, texts, three-dimensional drawings. However, a number of programs that claim to support DXF import implement only some of its capabilities. DXF changes with each version of AutoCAD. DXF and DXB file names use the extensions *.dxf, *.dxb, *.sld, *.adi.
BDF (Bitmap Distribution Format) is a raster format developed by the X Consortium for exchanging bitmap font data between 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 united by a single name).
BMP is a raster format developed by Microsoft for Windows OS; supported by all graphic editors working under its control, capable of storing both indexed (up to 256 colors) and RGB color (16.7 million shades). Most BMP files are stored in uncompressed form.
CDR (CorelDRAW Document) is a vector format initially known for its low stability and poor file compatibility. Many PC programs (FreeHand, Illustrator, PageMaker) can import CDR files. Starting from the seventh version, CorelDRAW in CDR files applies compression separately for vector and raster graphics; fonts can be embedded.
CGM (Computer Graphics Metafile) is a standard (ANSI and ISO) and metafile format for displaying vector images on the Web, adopted at the end of 1998 by the 3WC (WWW Consortium). The format is aimed at supporting a variety of graphic images, including artistic graphics, technical illustrations, cartography, computer publishing systems. Although CGM contains many graphics primitives and attributes, it is less complex than PostScript, allows for the creation of more compact files, and supports the exchange of complex, high-quality artistic images. The format used 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 of the Corel PHOTO-PAINT program, provides storage of full-color images and vector objects.
DPX (Digital Picture Exchange Format; also known as SMPTE Digital Picture Exchange Format) is a raster format designed to store one film frame or video data stream; developed by Kodak Cineon, adopted by ANSI and the US Society of Motion Picture and Television Engineers (SMPTE) with minor modifications as a standard. The format is supported by Kodak programs.
DWG is a vector format of the AutoCAD program from Autodesk, designed for storing drawings.
EMF (Enchanced Metafile) is a metafile format developed by Microsoft for storing images as a sequence of commands leading to the reproduction of images. In November 2005, the vulnerability of 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 the WMF vulnerability to download Trojan programs to a remote machine. Soon they appeared standalone versions viruses that spread as email worms in attached image files. Microsoft responded to this threat by issuing Security Advisory 912840 and (January 11, 2005) patching Windows XP, Windows 2000 (Service Pack 4), Windows Server 2003.
3DS (3D Studio, ASC) - a format developed by Autodesk, a three-dimensional modeling tool (“scene description”); also used as an interchange format. The format ensures optimal distribution of resources on the PC platform, supports all colors without restrictions, and has no compression. Many 3D modeling programs read and write files in this format. Strictly speaking, 3DS is two formats that are used as exchange formats - binary with the *.3ds extension and text with the *.asc extension.
EPS (Encapsulated PostScript, EPSF) is a simplified version of the PostScript format (PDL), developed by Adobe as a vector format, and later its raster version appeared - Photoshop EPS. The EPS format cannot contain more than one page in a single file and does not preserve a number of printer settings. Like PostScript print files, the EPS format records the final work, although programs such as Adobe Illustrator, Photoshop and Macromedia FreeHand can use it as a production tool.
FH8 (FreeHand Document) is the eighth version of the FH format, intended only for Macintosh PCs. FreeHand itself, Illustrator 7 and a limited number of programs from Macromedia can work with it. Since the seventh version, the FH format has full cross-platform compatibility, however, some FreeHand effects are not compatible 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 agencies) to store astronomical (obtained by orbital vehicles) 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, which do not support the common file format. FITS is considered a fairly simple, uncompressed format with an “unlimited number” of shades of gray. It can store many types of data, including raster, ASCII text, multidimensional matrices, binary tables.
GIF (Graphics Interchange Format) is a standard raster format for presenting 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 in which there are a lot of uniform fills (logos, inscriptions, diagrams), record an image “through the line” (Interlaced mode), thanks to which, 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 - a family of raster formats developed and supported for the MS-DOS, UNIX, Amiga platforms by Electronics Arts and Commodore-Amiga. A distinctive feature of IFF is its versatility: it can be used not only to support graphics, but also sound on all platforms except Amiga. IFF was previously known as the 24-bit format for MS-DOS, but it began to be replaced by the TIFF and TGA formats, and then by the JFIF format. Some characteristics of the IFF format: maximum image size 64 K by 64 K pixels; used in uncompressed and RLE compression versions, supports colors from 1- to 24-bit; “Major in Minor” number format, has a specification on CD; when used with MS-DOS and UNIX, file names may have *.iff and *.lbm extensions.
JFIF (JPEG File Interchange Format), JFI, JPG, JPEG - a raster format from C-Cube Microsystems, has become most widespread, 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 for storing illustrations in desktop publishing systems. The format was developed by Zsoft for the Paintbrush program, and after concluding an OEM agreement with Microsoft Corporation, it began to be used in various systems that work with graphics. Main characteristics: maximum image size 64 K by 64 K; 24-bit color support; uses RLE compression (can work without compression); supports work with CD-ROM. The PCX format versions are DCX and PCC, whose file names 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 for the purpose of transmitting them over the network in compressed form.
PDS (Planetary Data System Format) is a NASA 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 on all platforms.
PGML (Precision Graphics Mark-up Language) is a vector format that describes graphics in terms mathematical formulas, rather than raster pixels, which results in savings disk space and the ability to scale the image without losing its resolution and other quality indicators. The format was submitted to the W3C (WWW Consortium) for consideration as a network standard by Adobe Systems, IBM, Netscape, Sun Macromedia; used on the Internet.
Photo-CD (PCD, Kodak Photo CD) is a raster format developed by Eastman Kodak and designed for storing and playing full-color images (usually photographs) recorded at various resolutions on CDs. The format is supported by Photo CD ACCess, Photoshop, Shoebjx. The Photo CD format supports 24-bit colors, has its own compression system, a maximum image size of 2048x3072 pixels, allows you to store only one image per file, uses RLE and JPEG compression systems (in the DCT version). Kodak does not disclose further details.
PIC (Pictor PC Paint, PC Paint) - a raster format developed by Paul Mace for drawing programs on the MS-DOS platform, is a hardware-dependent format created taking into account the requirements of IBM family of graphics adapters (CGA, EGA, VGA). The PIC format is similar to the PCX format; the file names use the *.pic and *.clp extensions.
PICT (Macintosh QuickDraw Picture Format) is a standard for the Macintosh PC clipboard, supporting both raster and vector graphics. On a Macintosh PC, PICT works with all programs. On a PC it can be 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 intended to replace GIF. The format provides indexing of up to 256 colors, support for 24- and 48-bit color representation (True Color) and the implementation of a transparency channel (the so-called alpha channel). The dynamic lossless PNG image compression algorithm is 10-30% more efficient than a similar type of compression implemented in the GIF format.
PS (PostScript) - the format of the PostScript page description language (also known as the laser printer control language) was developed in 1984 by Adobe. The format is used for printing and storing fonts, as well as for exchanging documents formatted with it. The advantage of the PS format is that it uses independent specific devices playback system (including printer or screen type).
RAF (RAW) is a raster format used in digital cameras and maintains the image directly in the form in which it was captured by the camera sensor. Using this format eliminates artifacts associated with pre-processing of the image by camera software (for example, during JPEG compression) and provides the photographer with the ability to further process photographs (adjust 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 phototypesetting machines (Imagesetter) from Scitex Dolev, files of this format are output somewhat faster. On a PC, file names in the Scitex CT format have the extension *.sct.
SWF (Shockwave Flash) - internal vector format Flash programs from Macromedia, used for animation on the Internet.
TGA (TrueVision Targa) - a Truevision format developed for color television, supports RLE compression, file names have the *.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 preservation of the color of the original images. Subsequently, 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 for transferring 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 its apparent simplicity and versatility, it is recommended to use the WMF format only in extreme cases for transmitting so-called naked vectors. WMF distorts color and does not save a number of parameters that can be assigned to objects in different vector editors, is not understood by programs targeting the Macintosh PC. WMF files use the *.wmf extension.
VML (Vector Mark-up Language) is a vector format that was submitted to the W3C consortium by Microsoft, Hewlett-Packard, Autodesk, Macromedia, Visio; used on the Internet.
INTRODUCTION
A graphics format is a way of recording graphic information. Graphics file formats are designed to store images, such as photographs and drawings.
Knowledge file formats and their capabilities is one of the key factors in computer graphics. Yes, today there is no such kaleidoscope of extensions as in the early 90s, when each image editor company considered it its duty to create its own file type, or even more than one, but this does not mean that “everything needs to be saved in TIFF, but compress JPEG." Each of the established formats has undergone natural selection and has proven its viability. All of them have some characteristic features and capabilities that make them indispensable in their work. Knowledge of the features and subtleties of technology is also important for a modern designer. As an artist, it is necessary to understand the differences in the chemical composition of paints, the properties of soils, types of metals and rocks.
These are raster graphics, vector graphics, three-dimensional and fractal graphics. They differ in the principles of image formation when displayed on a monitor screen or when printed on paper.
Raster graphics are used in the development of electronic (multimedia) and printed publications. Illustrations made using raster graphics are rarely created manually using computer programs. Most often, scanned illustrations prepared by the artist on paper or photographs are used for this purpose. Recently, digital photo and video cameras have found widespread use for inputting raster images into a computer. Accordingly, most graphic editors designed for working with raster illustrations are focused not so much on creating images, but on processing them. On the Internet, raster illustrations are used in cases where it is necessary to convey the full range of shades of a color image.
Software tools for working with vector graphics, on the contrary, are intended primarily for creating illustrations and, to a lesser extent, for processing them. Such tools are widely used in advertising agencies, design bureaus, editorial offices and publishing houses. Design work based on the use of fonts and simple geometric elements is solved by means vector graphics much easier. There are examples of highly artistic works created using vector graphics, but they are the exception rather than the rule, since the artistic preparation of illustrations using vector graphics is extremely complex.
Three-dimensional graphics are widely used in engineering programming, computer modeling of physical objects and processes, animation, cinematography and computer games.
Software tools for working with fractal graphics are designed to automatically generate images through mathematical calculations. Creating a fractal artistic composition is not about drawing or design, but about programming. Fractal graphics are rarely used to create printed or electronic documents, but they are often used in entertainment programs.
The purpose of this test will be an initial study of graphic files and their formats, information compression methods, as well as an analysis of the work done.
The objective of this test will be to determine whether a graphic format belongs to a specific subtype: vector, raster, complex.
Information compression methods
Almost all modern graphics file formats use some kind of information compression method, therefore, for a better understanding of further material, the beginning of this section contains a brief summary of these methods.
Information compression methods:
One of the simplest compression methods is the RLE (Run Length Encoding) method. The RLE method works by searching for identical pixels in the same row. If a line, say, has 3 white pixels, 21 black, then 14 white, then using RLE makes it possible not to remember each of them (38 pixels), but to write it as 3 white, 21 black and 14 white in the first line .
The LZW (Lempel-Ziv-Welch) compression method was developed in 1978 by Lempel and Ziv, and later refined in the USA. Compresses data by searching for identical sequences (called phrases) throughout the file. The identified sequences are stored in a table and are assigned shorter markers (keys). So, if an image contains sets of pink, orange and green pixels, repeated 50 times, LZW detects this, assigns this set single number (for example, 7) and then stores this data 50 times as the number 7. The LZW method, like RLE, performs better in areas of uniform, noise-free colors, and it performs much better than RLE at compression arbitrary graphics data, but the encoding and decompression process is slower.
The Huffman compression method was developed in 1952 and is used as a component in a number of other compression schemes, such as LZW, Deflation, JPEG. The Huffman method takes a set of symbols and analyzes them to determine the frequency of each symbol. The most frequently occurring characters are then represented in the smallest possible number of bits. For example, the letter "e" is most often found in English texts. Using Huffman encoding, you can represent "e" with just two bits (1 and 0), instead of the eight bits needed to represent the letter "e" in ASCII.
The CCITT (International Telegraph and Telephone Committie) compression method was developed for facsimile transmission and reception. It is a narrower version of Huffman coding. CCITT Group 3 is identical to the fax message format, CCITT Group 4 is the fax format, but without special control information.
Graphics file formats
Raster format
Raster images are formed in the process of scanning multi-color illustrations and photographs, as well as when using digital photo and video cameras. You can create raster image directly on your computer using a raster graphics editor.
A raster image is created using dots of different colors (pixels) that form rows and columns. Each pixel can take on any color from a palette containing tens of thousands or even tens of millions of colors, so raster images provide highly accurate color and grayscale reproduction. The quality of a raster image increases with increasing spatial resolution (the number of pixels in the image horizontally and vertically) and the number of colors in the palette.
The disadvantage of raster images is their large information volume, since it is necessary to store the color code of each pixel.
Let's look directly at the extensions of the raster graphics format:
1) The BMP file format (short for BitMaP) is the native raster graphics format for Windows because it most closely matches the native Windows format in which that system stores its raster arrays. The filename extension most often used in BMP format is BMP, although some files have the extension RLE, which stands for run length encoding. The RLE extension of a file name usually indicates that the file's raster information has been compressed using one of two RLE compression methods that are valid for BMP format files.
In BMP files, the color information of each pixel is encoded into 1, 4, 8, 16, or 24 bits (bits/pixel). The number of bits per pixel, also called color depth, determines the maximum number of colors in an image. An image with a depth of 1 bit/pixel can have only two colors, and with a depth of 24 bit/pixel - more than 16 million different colors.
2) PCX became the first standard graphics file format for storing raster graphics files on IBM PCs. This format, used in the ZSoft Paintbrush program, was used in the early 80s. Microsoft acquired a license and then distributed it along with Microsoft products. The format was later converted into Windows Paintbrush and began to be distributed on Windows. Although the use of this popular format is declining, PCX files, easily recognized by their PCX extension, are still widely used today.
PCX files are divided into the following three parts: a PCX header, raster array data, and an optional color table. The 128-byte PCX header contains several fields, including the image size and the number of bits to encode color information for each pixel. The raster array information is compressed using simple method RLE compression; An optional color table at the end of the file contains 256 RGB color values that define the colors of the image. The PCX format was originally developed for CGA and EGA display adapters and has been modified for use in VGA and true color adapters. The color coding of each pixel in modern PCX images can be done at 1, 4, 8, or 24 bit depth.
3) If PCX is one of the easiest raster graphics formats to decode, then TIFF (Tagged Image File Format) is one of the most complex. TIFF files have the extension TIFF. Each file begins with an 8-byte Image File Header (IFH), the most important element of which, the Image File Directory (IFD), serves as a pointer to the data structure. An IFD is a table for identifying one or more variable length pieces of data called tags; tags store information about an image. The TIFF file format specification defines over 70 different types of tags. For example, one type of tag stores information about the width of the image in pixels, while another stores information about its height. The third type tag stores a color table (if necessary), and the fourth type tag contains the raster array data itself. An image encoded in a TIFF file is defined entirely by its tags, and the file format is easily extensible because additional tag types can be defined to add additional properties to the file.
So what makes TIFF so difficult? On the one hand, writing programs that distinguish between all types of tags is not an easy task. Most TIFF file readers implement only a subset of the tags, which is why a TIFF file created by one program sometimes cannot be read by another. Additionally, programs that create TIFF files can define their own tag types that are meaningful only to them. TIFF file readers can skip tags they don't understand, but there is always the danger that this will affect the appearance of the image.
Another complication is that a TIFF file may contain multiple images, each with its own IFD and set of tags. The raster array data in a TIFF file can be compressed using any of several methods, so in reliable program To read TIFF files there must be decompression tools RLE, LZW (LempelZivWelch) and several others. The situation is further aggravated by the fact that the use of LZW unpacking programs must be carried out in accordance with license agreement with Unisys Corp. for the right to use the LZW algorithm and often for a fee. As a result, even the best TIFF readers often give up when faced with an LZW-compressed image.
Despite its complexity, the TIFF file format remains one of the best for transferring raster arrays from one platform to another due to its versatility, which allows almost any image to be encoded in binary form without losing its visual or any other attributes.
4) Most of the leading graphics professionals dealing with the LZW algorithm face similar legal problems when using the popular cross-platform raster graphics file format GIF (Graphics Interchange Format, pronounced "gif"), developed by CompuServe. GIF files are typically named using the GIF extension, and thousands of them are available from CompuServe.
The structure of a GIF file depends on the version of the GIF specification that the file conforms to. There are currently two versions in use, GIF87a and GIF89a. The first one is simpler. Regardless of the version number, GIF file begins with a 13-byte header containing a signature that identifies the file as a GIF, the GIF version number, and other information. If the file stores only one image, following the header there is usually a general color table that defines the colors of the image. If several images are stored in a file (the GIF format, similar to TIFF, allows you to encode two or more images in one file), then instead of a general color table, each image is accompanied by a local color table.
5) PNG format(Portable Network Graphic, pronounced "ping") was developed to replace GIF to get around the legal barriers to using GIFs. PNG inherits many of the features of GIF and, in addition, it allows you to store true color images. More importantly, it compresses raster array information using a variant of the highly respected LZ77 compression algorithm (predecessor to LZW), which anyone can use for free.
6) The JPEG (Joint Photographic Experts Group, pronounced JPEG) file format was developed by C-Cube Microsystems as an efficient method for storing images with high color depth, such as those obtained by scanning photographs with numerous subtle sometimes subtle) color shades. The biggest difference between the JPEG format and the other formats discussed here is that JPEG uses a lossy compression algorithm (rather than a lossless algorithm) to preserve information about the image so that the decompressed image is preserved. The image is exactly the same as the original. Lossy compression sacrifices some of the image information to achieve a higher compression ratio. The decompressed JPEG image rarely matches the original exactly, but very often the differences are so small that they are barely (if at all) possible. discover.
Vector format
In this subsection, we will look at the most common extensions for vector graphics files.
1) Encapsulated PostScript (EPS) - an extension of the PostScript format, data in which is recorded in accordance with the DSC (English, Document Structuring Conventions) standard, but with a number of extensions that allow this format to be used as a graphic one.
The EPS format was created by Adobe based on the PostScript language and served as the basis for the creation earlier versions Adobe Illustrator format.
In its minimal configuration, an EPS file has a so-called BoundingBox DSC comment - information describing the size of the image. This way, even if the application cannot rasterize the data contained in the file, it has access to the image dimensions and its preview.
QuarkXPress versions 4, 5 and 6 cannot rasterize data from an EPS file, so it uses only a preview in the layout - a small copy of the entire image, which is stored in the EPS file separately from the main data. Adobe InDesign versions CS-CS4 do not have such a limitation. The use of a reduced-quality copy of the image is intended to simplify the display of the image on the screen and, as a result, significantly speed up the work with layout. Preview can be recorded in TIFF or WMF format (PC only) or omitted altogether.
The format is used in professional printing and can contain raster images, vector images, and combinations thereof.
An image recorded in EPS format can be saved in different color spaces: Grayscale, RGB, CMYK, Lab, Multi-channel.
The data structure of an EPS raster file can be written using different methods: ASCII data (text data), Binary data (binary data) and JPEG with different compression ratios.
2) WMF (Windows MetaFile) - a universal format of vector graphic files for Windows applications. Used to store a collection of Microsoft Clip Gallery graphics. The format was developed by Microsoft and is an integral part of Windows, as it preserves a sequence of hardware-independent GDI (Graphical Device Interface) functions that directly output an image to a given context graphics device(on the screen, on the printer, etc.). Very often, WMF is used implicitly to save an image of a program's output window and restore it later, as well as when transferring information via the clipboard. From MS Windows, writing and reading a file of this format is extremely simple and fast; in other operating systems, support for this format is useless. Some Macintosh programs understand it. On the Macintosh platform, the PICT format plays a similar role.
3) CDR file format - a vector image or drawing created using the CorelDRAW program. This file format was developed by Corel for use in its own software products. CDR files are not supported by many image editing programs. However, the file can be exported using CorelDRAW to other, more common and popular image formats.
Also, the CDR file can be opened with Corel Paint Shop Pro. For best compatibility, Corel recommends saving files in CorelDRAW CDR format version 9.0 or earlier.
4) Portable Document Format (PDF) is a cross-platform electronic document format created by Adobe Systems using a number of PostScript language features. Primarily intended for electronic presentation of printed products, a significant amount of modern professional printing equipment can process PDF directly. To view, you can use the official free Adobe Reader program, as well as third-party programs. The traditional way of creating PDF documents is a virtual printer, that is, the document as such is prepared in its own specialized program - a graphics program or text editor, CAD, etc., and then exported to PDF format for distribution in electronic form, transfer to a printing house, etc.
Complex format
There are also complex formats that can store both vector and raster information. These are the formats DjVu, CGM, AI (format of the Adobe Illustrator program), EPS (Encapsulated PostScript - a professional universal vector-raster format used by all professional graphic programs) and PDF (Portable Document Format - format Adobe programs Acrobat, which can contain raster and vector graphics, as well as text information).
1) DjVu (from the French déjà vu - “already seen”) - a lossy image compression technology designed specifically for storing scanned documents - books, magazines, manuscripts, etc., where the abundance of formulas, diagrams, drawings and handwritten symbols makes it extremely labor-intensive their full recognition. It is also an effective solution if it is necessary to convey all the nuances of design, for example, of historical documents, where not only the content is important, but also the color and texture of the paper; parchment defects: cracks, marks from folding; corrections, blots, fingerprints; traces left by other objects, etc.
DjVu has become the basis for several libraries of scientific books. A huge number of books in this format are available on file-sharing networks.
The format is optimized for network transmission so that the page can be viewed before the download is complete. A DjVu file can contain a text (OCR) layer, which allows full-text search of the file. In addition, a DjVu file can contain a built-in interactive table of contents and active areas - links, which allows for convenient navigation in DjVu books.
2) CGM (from the English Computer Graphics Metafile) - a format for storing and exchanging graphic data that is not related to CAD.
3 Dpolygons
The X file format is a file format for storing 3D objects created by Microsoft.
This format stores information about the geometry of a 3D object (vertex coordinates and normal coordinates), texture coordinates, description of materials, paths and names of textures that are used. The hierarchy of objects is stored, the animation is stored, and the bindings of vertices to “bones” with a description of the weights are stored. The X file may not contain any information about the object (for example, the X file may only contain vertex coordinates).
An X file can be text or binary.
At the beginning of the X file there is a header, then there is a description of information about the object. The description of information can be in any order, but the title always comes at the very beginning.
CONCLUSION
No other computer application can boast such a variety of file format types as computer graphics. Every more or less reputable software company considers it their duty to create at least some kind of graphic editor, and in addition to it, of course, they create their own own format files in which, as the developers assure, this editor saves masterpieces created with its help, in the best possible way. As a result of this approach, a situation has arisen where no one is able to cover all the variety of types of existing graphic formats. Graphic files are quite complicated, unlike, say, a simple text file. Over time, the need arose to obtain graphic files with certain requirements. For example, a computer artist needs very high quality pictures, for the average user - good quality, but not a very large volume; a web designer needs to get a more or less decent image with a minimum volume. But the requirements for file portability between different applications forced the identification of several specific formats, which have become, each in their own area, de facto standards. Thus, for images on the Internet, in most cases, JPEG and GIF formats are used, for storing images - JPEG, in publishing TIFF reigns, etc.
This is not to say that there are bad formats and there are good ones. Each format has advantages and disadvantages. This article will talk about only some of the graphic formats that are supported by most graphics programs and are used in practice more often than others.
Raster images are saved in a file in the form of a rectangular table, in each cell of which the binary color code of the corresponding pixel is written. Such a file stores data about other properties of the graphic image, as well as its compression algorithm.
Vector images are saved in a file as a list of objects and the values of their properties - coordinates, sizes, colors, etc.
There are quite a large number of both raster and vector graphic file formats. Among this variety of formats, there is no ideal one that would satisfy all possible requirements. The choice of one or another format for saving an image depends on the goals and objectives of working with the image. If photographic accuracy of color reproduction is needed, then preference is given to one of the raster formats. It is advisable to store logos, diagrams, and design elements in vector formats. The file format affects the amount of memory the file occupies. Graphic editors allow the user to independently choose the format for saving the image. If you are going to work with a graphic image in only one editor, it is advisable to choose the format that the editor offers by default. If the data will be processed by other programs, it is worth using one of the universal formats.
There are universal graphics file formats that simultaneously support both vector and raster images.
List of used literature
1. Angel E. Interactive computer graphics. Introductory course at the base. Second edition. M., St. Petersburg, Kyiv, Williams Publishing House, 2001;.
2. Rogers D., Adams J. Mathematical foundations of machine graphics. M., Mir, 2001;.
3. E. V. Shishkin, A. V. Boreskov “Computer graphics: polygonal models”, M., Dialog-MEPhI, 2001.
4. Ivanov V. P., Batrakov A. S. Three-dimensional computer graphics. M., Radio and Communication, 1995;.
5. Gniloy V. Interactive computer graphics. – M.: Mir, 1981.
File formats are the basis of working with digital photographs. will tell you about all the major graphic file formats.
RAW.
A file format containing raw information coming directly from the camera sensor. These files are not processed by the camera's processor (unlike JPG) and contain original shooting information. RAW can be compressed without loss of quality.
The advantages of RAW are obvious - unlike JPG, which was processed in the camera and already saved with data compression - RAW gives the widest possibilities for processing photographs and maintains maximum quality.
Note. Different camera manufacturers use different algorithms to create RAW in their cameras. Each manufacturer comes up with its own resolution for its RAW file - NEF - Nikon, CR2 - Canon...
JPEG (aka JPG).
This is the most common graphics file format.
JPG has earned its popularity due to its flexible data compression capabilities. If necessary, the image can be saved with maximum quality. Or compress it to the minimum file size for transmission over the network.
JPG uses a lossy compression algorithm. What does this give us? An obvious disadvantage of such a system is the loss of image quality every time a file is saved. On the other hand, image compression simplifies data transfer by 10 times.
In practice, saving a photo with minimal compression does not result in any visible degradation in image quality. That is why JPG is the most common and popular format for storing graphic files.
TIFF.
The TIFF format is very popular for storing images. It allows you to save photos in various color spaces (RBG, CMYK, YCbCr, CIE Lab, etc.) and with high color depth (8, 16, 32 and 64 bits). TIFF is widely supported graphic applications and is used in printing.
Unlike JPG, a TIFF image will not lose quality every time the file is saved. But, unfortunately, precisely because of this TIFF files weigh many times more than JPG.
The rights to the TIFF format are currently owned by Adobe. Photoshop can save TIFF without merging layers.
PSD.
The PSD format is used in Photoshop program. PSD allows you to save a raster image with many layers, any color depth and in any color space.
Most often, the format is used to save intermediate or final results of complex processing with the ability to change individual elements.
PSD also supports compression without loss of quality. But the abundance of information that a PSD file can contain greatly increases its weight.
BMP.
The BMP format is one of the first graphic formats. It is recognized by any program that works with graphics; format support is integrated into the Windows and OS/2 operating systems.
BMP stores data with a color depth of up to 48 bits and a maximum size of 65535x65535 pixels.
At the moment, the BMP format is practically not used either on the Internet (JPG weighs several times less) or in printing (TIFF copes with this task better).
GIF.
The GIF format was created in the early days of the Internet for sharing images. It can store lossless compressed images in up to 256 colors. The GIF format is ideal for drawings and graphics, and also supports transparency and animation.
GIF also supports compression without loss of quality.
PNG.
The PNG format is designed to both improve and replace GIF format graphic format, which does not require a license to use. Unlike GIF, PNG has alpha channel support and the ability to store an unlimited number of colors.
PNG compresses data without loss, which makes it very convenient for storing intermediate versions of image processing.
JPEG 2000 (or jp2).
A new graphics format created to replace JPEG. For the same quality, JPEG 2000 file size is 30% smaller than JPG.
With strong JPEG compression 2000 does not split the image into squares, characteristic JPEG format.
Unfortunately, at the moment this format is not very widespread and is supported only by Safari and Mozilla/Fireox browsers (via Quicktime).
There are two types of graphic files, raster and vector, which have different formats.
- raster graphics files correspond to the formats *.bmp, *.tif, *psd, *.gif, *.png, *.jpg;
- vector graphics file corresponds to the formats *.wmf, *.eps, *.cdr, *.ai
Knowledge of file formats is the basis for working with digital photographs. they determine how the information is stored in the file (raster or vector), as well as the form in which the information is stored (the compression algorithm used). Compression is used for raster graphics files, since they are usually quite large. Compressing graphic files differs from archiving them using archiving programs (gag, zip, arj, etc.) in that the compression algorithm is included in the graphic file format.
Basic graphic file formats
RAW
Translated from English - raw. The format used in the photo processing process contains raw information that comes directly from the camera sensor and does not have a clear specification. These files are not processed by the camera's processor (unlike JPG) and contain original shooting information. RAW can be compressed without loss of quality. Unlike JPG, which was processed in the camera and already saved with data compression, RAW gives the widest possibilities for processing photographs and maintains maximum quality.
In other words, under RAW format refers to data obtained directly from the matrix without processing.
Different camera manufacturers use different algorithms to create RAW in their cameras. Each manufacturer comes up with its own resolution for its RAW file - NEF, NRW - Nikon; CRW, CR2 – Canon.
JPEG (or JPG)
This is the most common graphics file format. JPEG has earned its popularity due to its flexible data compression capabilities. If necessary, the image can be saved with maximum quality. Or compress it to the minimum file size for transmission over the network. When saving a JPEG file, you can specify the degree of quality, and therefore the degree of compression, which is usually specified in some conventional units, for example, from 1 to 100 or from 1 to 10. A larger number corresponds to better quality, but the file size increases. Usually, the difference in quality between 90 and 100 is practically not perceived by eye.
JPEG uses a lossy compression algorithm. What does this give us? An obvious disadvantage of such a system is the loss of image quality every time a file is saved. On the other hand, image compression simplifies data transfer by 10 times. In practice, saving a photo with minimal compression does not result in any visible degradation in image quality. That is why JPG is the most common and popular format for storing graphic files.
TIFF (Tagged Image File Format)
TIFF format is a format for storing raster graphics. It was originally developed by Aldus in collaboration with Microsoft for use with PostScript. It allows you to save photos in various color spaces (RBG, CMYK, YCbCr, CIE Lab, etc.) and with high color depth (8, 16, 32 and 64 bits). TIFF is used in scanning, faxing, text recognition, printing, and is widely supported by graphics applications. It is possible to save an image in a TIFF file with or without compression. Compression levels depend on the characteristics of the image being saved, as well as on the algorithm used. Unlike JPG, a TIFF image will not lose quality every time the file is saved. But, unfortunately, it is precisely because of this that TIFF files weigh many times more than JPG.
PSD (Photoshop Document)
Photoshop Document (PSD) is an original raster format for storing graphic information using lossless compression, created specifically for Adobe Photoshop and supporting all its capabilities. It allows you to save a raster image with many layers, any color depth and in any color space. Most often, the format is used to save intermediate or final results of complex processing with the ability to change individual elements. PSD also supports compression without loss of quality. But the abundance of information that a PSD file can contain greatly increases its weight.
BMP (Bit MaP image)
Bit MaP image (BMP) - universal format raster graphics files, used in the operating room Windows system. This format is supported by many graphic editors, including Paint editor. Recommended for storing and exchanging data with other applications. The BMP format is one of the first graphic formats. It is recognized by any program that works with graphics. BMP stores data with color depth in this format from 1 to 48 bits per pixel, maximum dimensions images 65535×65535 pixels. At the moment, the BMP format is practically not used either on the Internet (JPG weighs several times less) or in printing (TIFF copes with this task better).
GIF (Graphics Interchange Format)
format for storing raster graphics. The GIF format is capable of storing compressed data without loss of quality in up to 256 colors. Includes a lossless compression algorithm that allows you to reduce the file size by several times. An image in GIF format is stored line by line; only the format with an indexed color palette is supported. Recommended for storage; images created programmatically (diagrams, graphs, etc.) and drawings (such as appliqué) with a limited number of colors (up to 256). Used to place graphic images on Web pages on the Internet.
PNG (Portable network graphics)
A raster format for storing graphic information using lossless compression. PNG was created to both improve upon and replace the GIF format with a graphics format that does not require a license for use. Unlike GIF, PNG has alpha channel support and the ability to store an unlimited number of colors. PNG compresses data without loss, which makes it very convenient for storing intermediate versions of image processing. Used to place graphic images on Web pages on the Internet.
JPEG 2000 (or jp2)
A graphic format that, instead of the discrete cosine transform characteristic of JPEG, uses wavelet transform technology, which is based on representing the signal as a superposition of some basic functions - wave packets. As a result of this compression, the image is smoother and clearer, and the file size compared to JPEG with the same quality is reduced by another 30%. Speaking in simple language, with the same quality, the file size in JPEG 2000 format is 30% smaller than JPG. When highly compressed, JPEG 2000 does not break the image into squares characteristic of the JPEG format. Unfortunately, at the moment this format is not very widespread and is supported only by Safari and Mozilla/Firerox browsers (via Quicktime).
WMF (Windows MetaFile)
A universal format of vector graphics files for Windows applications. Used to store a collection of Microsoft Clip Gallery graphics.
CDR (CorelDRaw files)
The original vector graphics file format used in the CorelDraw vector graphics processing system.
AI (AdobeIllustrator files)
An original vector graphics file format used in the AdobeIllustrator vector graphics processing system.
EPS (Encapsulated PostScript)
The format of vector graphics files is supported by programs for various operating systems.
Here are almost all the most common ones graphic file formats, which a self-respecting photographer and designer should know.