In what format should graphic files be stored? Common graphic file formats, their advantages, disadvantages and applications
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 graphic format in Windows. Almost all graphics programs can create and read the BMP format. Standard format graphic files for Windows. Almost all Windows image editing programs 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 Microsoft program Word. 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 electronic presentation of printed products. To display this format, the free Adobe Reader program is used.
TXT– a document containing unformatted text. In Windows, it is created and opened with a 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 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 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. Besides AutoCAD format 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) - standard (ANSI and ISO) and metafile display format vector images on the Web, adopted at the end of 1998 by the 3WC consortium (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 uses different types of 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, stand-alone versions of viruses appeared, spreading in the form of email worms in attached image files. Microsoft responded to this threat by issuing Security Advisory 912840 and (January 11, 2005) hotfix Windows systems 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 “unlimited” 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 different systems working 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 saves disk space and allows you 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 the 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) - format of the PostScript page description language (also known as the control language laser printers) 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 a device-independent 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, high-resolution graphic images obtained by scanning. The format is characterized high quality transfer and preserve the color of 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, does not save a number of parameters that can be assigned to objects in various vector editors, and 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.
As is known, depending on the method of image formation on the monitor screen, computer graphics are usually classified into several types:
- raster
- vector
- fractal
- three-dimensional
I think the reader already knows all this. Therefore, today we will consider the most common and popular raster graphics formats. In future publications, I plan to describe file formats for other types of computer graphics, in particular vector ones. Having described these formats, I will give my recommendations for their practical use in everyday life, i.e. what format for what and where to use
Basics of raster graphics
Raster graphics is a graphic represented on a computer as a set of dots (pixels). Each pixel contains color information. The pixel size is very small, so the human eye perceives the entire image without dividing it into pixels.
For raster graphics, an important characteristic is image resolution. The same picture can be presented with better and worse quality according to the number of dots (pixels) per unit length.
Permission— number of points per unit of measurement.
dpi (dots per inch)— number of dots per inch.
ppi (points/pixels per inch)- pixels per inch.
Pixel— raster point of the screen image. All images are divided into dots. Pixel is the smallest point. The image can no longer be divided. In addition, a pixel is a dot of one color; it is impossible to color half a pixel one color and the other half another.
Don't confuse image resolution, monitor resolution, and printer resolution. These are different things.
Having remembered the basics of raster graphics, let's move on to a description of raster graphics storage formats.
Image storage formats in raster graphics
File Format- method of saving electronic parts, which make up a computer file. Different formats organize file saving in different ways. I will not consider all existing raster graphics formats (and I could not); we will consider only the most common and popular ones.
BMP(Bit Map - bit carat). This format initially used the simplest encoding - pixel by pixel (the most wasteful), which was done sequentially in lines, starting from the lower left corner of the graphic image. Files of this format were included in the first versions Windows. This format used only 256 colors, i.e. a pixel is represented by only one byte. Later, the format began to be used to save full-color images. Format BMP- one for standard raster graphics formats.
TIFF (Taged Image File Format)- a standard format in topographic graphics and publishing systems. TIFF files provide best quality print. Due to its large size, this format is not used when creating Web sites and publishing on the Internet.
Format TIFF is one of the most universal and widespread raster graphics formats. It was created as a cross-platform universal format for color images. Working with it is supported by almost all programs for working with bitmap graphics. Can store graphics in monochrome, in RGB And CMYK color representations.
The format includes internal compression. It has an open architecture - it is possible to declare information about the type of image in the header, i.e. versions of it can be used in the future to present new developments. Accompanying information of transmitted images (signatures, etc.) is also saved in the format. Image format TIFF are stored in files with the extension .tif.
GIF format (Graphic Interchamge Format) is a graphics data exchange format that is used for recording and storing raster graphics. This format differs from other raster graphics formats in that it for a long time supported online. Uses indexed colors (limited set of colors). This is one of the most common image formats distributed on the Internet and used to create Web sites.
Images in GIF .gif. To the benefits GIF The important thing about images is that the appearance of the image is independent of the browser and platform. Drawings, drawings and images with a small amount of solid color, transparent images and animation sequences (this is a very well-known feature of this graphics format) are displayed best. IN GIF Images are compressed without losing information.
JPEG format (Joint Photographic Expert Group)— designed for storing compressed images. The image compression method it uses was developed by a team of photography experts. The decoding of the abbreviation immediately becomes clear JPEG— a joint group of experts in photo processing.
JPEG is one of the most powerful image compression algorithms. In practice, it is the de facto standard for storing full-color images. Format JPEG was created in order to get rid of the restrictions that were imposed on images created in GIF format.
The algorithm operates on areas of 8? 8, in which the brightness and color changes relatively smoothly. Compression in JPEG carried out by smoothly changing colors in the image. A high compression ratio is provided, the value of which reaches 100 and depends on the permissible level of loss of visual information.
The format is widely used in documents HTML and for data transmission over the network. Saves graphics settings in color representation RGB(usually). Images in JPEG format are stored in files with the extension .jpg.
Programs that work with JPEG, use lossy compression algorithms, they exclude from the image those data that are considered unimportant. Before applying the compression algorithm, the image is divided into rectangular areas. When compressing there is a risk of getting fuzzy, blurry image with distortion of details.
JPEG 2000 format (jp2)
This format was developed to replace JPEG. When saving images with the same compression level, images saved in JPEG 2000, are sharper and take up less disk space. In addition, this format solves the problem with the appearance of defects JPEG, which appeared when saving with a high compression ratio (a lattice of 8 × 8 pixel blocks).
The format is not supported in all browsers, which greatly hinders the spread of this format.
PNG (portable network graphics)- a raster graphics storage format that uses lossless compression. PNG is a free format (unlike GIF), so it is widely used.
It is a very powerful and widely used format on the Internet and other areas of computer graphics.
WMF format
WMF format (Windows Metafile Format)- used to exchange graphic data between OS applications Microsoft Windows. IN WMF files can store both vector and raster images. Images in WMF format are stored in files with the extension .wmf.
PSD and CDR formats
PSD format (PhotoShop Document)— internal format for the package Adobe Photoshop. Allows you to save layers in an image and supports all types of graphics. Images in PSD format are stored in files with the extension .psd.
CDR format— internal format for the company’s software package CorelDRAW. Images and text prepared in the program CorelDRAW V CDR format, stored in files with the extension .cdr.
Recommendations for using different raster graphics formats
Now I will try to move from theory to practice and consider areas of application various formats raster graphics depending on their characteristics. The characteristics of the formats are as follows: the type of compression used, support for transparent colors, the ability to create simple animations, support for line-by-line image output for gradual loading in the browser, and the number of colors used in the image.
Using GIFs
Format characteristics:
- Compression support: lossless (Lempel-Ziv-Welch, LZW)
- Transparency support: Yes
- Animation support: Yes (a distinctive feature of this format)
- Yes (interlaced)
- Number of colors: indexed colors (256 colors)
- all platforms
Recommendations: it is advisable to use this format in Web, for images without smooth color transitions (logos, banners, inscriptions, diagrams). Nice guy compression and a small number of supported colors allow you to save space when storing graphics, and can also be used when creating websites for more fast loading HTML-pages. Interlaced scanning makes it possible to see and evaluate the downloaded image without waiting for the download to complete. However, the limited range of colors makes this format unsuitable for storing images with smooth transitions, gradients, etc. Mainly used on the Internet.
Using PNG
Format characteristics:
- Compression support: lossless compression (Deflate)
- Transparency support: Yes
- Animation support: Yes(APNG)
- Interlaced display support: Yes (two-dimensional interlacing)
- Number of colors: Deep Color
- Compatibility with other platforms: all platforms
Recommendations: the most advanced compression algorithm in PNG allows you to save files smaller in size than in GIF. The ability to use absolutely any color and the use of transparency make this format a leader in terms of use in Web. I would recommend using it instead GIF. Scope of application - used in design Web-sites, image editing, etc. This is a universal format with a great future.
Using JPEG
Format characteristics:
- Compression support: lossy compression
- Transparency support: absent
- Animation support: absent
- Interlaced display support: Yes (Progressive JPEG)
- Number of colors: True Color (RGB and CMYK models)
- Compatibility with other platforms: all platforms
Recommendations: This format should be used to store a large number of images (photos) on your hard drive, which will significantly save its working space (thanks to its excellent compression type). It needs to store large-sized photographs with a lot of smooth transitions. Small size final files, allows you to effectively use JPEG for publishing photos on the Internet. But you should not save the same images in JPEG several times - this will lead to defects and “damage” the image.
Using TIFF
Format characteristics:
- Compression support: supports the ability to apply different compression algorithms (depending on the image being saved)
- Transparency support: absent
- Animation support: absent
- Interlaced display support: absent
- Number of colors: 8, 16, 32 and 64 bpc (Lab, RGB and CMYK models)
- Compatibility with other platforms: all platforms
Recommendations: this powerful format is used in printing, publishing systems, etc. Files in this format are stored for future printing. TIFF Used to store scanned images, faxes, etc. illustrations.
Using BMP
Format characteristics:
- Compression support: It is possible to use lossless compression (Run Length Encoding, RLE)
- Transparency support: absent
- Animation support: absent
- Interlaced display support: absent
- Number of colors: RGB model, color depth 24 bits
- Compatibility with other platforms: Windows only
Recommendations: This format is not suitable for use in Web, typography and even for storing images (due to the lack of image compression). Used only because it is "embedded" in the OS Windows default.
Conclusion
I hope this article helped you understand a little about the variety of raster graphics formats. My recommendations will help you decide on the choice of format for storing graphics. In short, in JPEG store photos in GIF- banners and logos (but it is advisable to gradually move on to PNG), A TIFF used to prepare documents for printing.
Today we will talk about image formats, their features and distinctive features. Many of us know that images come in different formats, but not everyone understands why there are so many of them and what their distinctive features are.
Any image stored on a computer has its own graphic format. Each of the graphic formats has its own properties and purpose. Today there are a huge number of graphic formats. We will consider most of the graphic formats based on one of the most popular graphic editors, Adobe Photoshop. Why Photoshop, it’s simple, this graphic editor has the largest number of formats.
But in addition, we will try to analyze other widely known image formats.
So let's get started:
PSD- This own format Adobe Photoshop program, it allows you to save all the work done on the image. Namely transparency, layer blending modes, shadows, layers, layer masks and all the other little things done with the image. This format is usually used if the image is not completely finished. It is also often used to develop a website layout, since it is convenient to make layout from this file, seeing all the layers and elements. And in all other cases there is no point in using it, since it has a significantly large file size compared to other formats.
TIFF– allows you to save the prepared Photoshop project as accurately as possible. It contains not only pixel information, but also the density of pixels per image when printed in dpi. It can also store several image layers plus channel transparency information. This format was used mainly in printing.
BMP- This is a dot pattern. An image in this format consists of a mass of dots, each of which contains its own color. This format is very large and can be easily compressed by archivers. The quality loss in BMP is not significant, however, it is inferior to TIFF.
JPEG is the most widely used format. It is widely used in digital technology (cameras). The reason for such widespread use is that it is quite bad quality and small file size. But the small size means that image quality is significantly lost. It's all about the image compression algorithm; it consists in the fact that, when compressed, the image significantly loses accuracy. For these reasons, it is not advisable to use this format in printing. But the advantage is that it is convenient to send them by email ( email), post it on the Internet and store it on disk.
GIF– Primarily used to produce graphics for the Internet. It is not suitable for saving photographs, as it has a limitation in color reproduction; for the same reasons, it is not suitable for printing. The image of this graphic format consists of dots, which can include from 2 to 256 colors. Limited color rendering and support for transparency make it indispensable for storing images with minimal colors, such as logos. Another feature of the format is the ability to produce animated images. Widely used for creating gifs(animated) banners.
EPS– can be called the most reliable and universal format. It is mainly intended for transmission to publishing houses; the format can be created and used by almost all graphic editors. It makes the most sense to use this format only if the output is on a PostScript device.
This format is unique; it supports everything necessary for printing, it can write data in RGB, clipping paths, as well as the use of fonts and more. Initially, EPS was developed as a vector format, but later its raster version appeared - Photoshop EPS.
PNG is a graphic format that has recently replaced Gif format, and has already become very popular due to the fact that it can maintain transparency and translucency, which was not possible in its predecessor gif. This means that the png maintains translucency in the range from 1 to 99% using an alpha channel with 256 levels of gray. Transparency works as follows: gamma correction information is written to the file. Gamma correction is a certain number of brightness, contrast of the monitor. This number is subsequently read from the file and allows you to adjust the image display by adjusting the brightness.
PICT is a proprietary Macintosh format. The format is capable of including both raster and vector information, text, as well as sound, and uses RLE compression. Bitwise PICT images can have absolutely any bit depth. Vector PICT images, which have virtually disappeared from use these days, had unusual problems line thickness and other deviations during printing.
The format is used for Macintosh, and when creating certain presentations only for Mac. On regular computers(not Mac) PICT - the format is presented with the extension .pic or .pct, read by certain programs, working with this format is often not easy.
PDF– the format was proposed and developed by Adobe as a format for electronic documentation, various presentations and layout for sending it by e-mail. And its design feature was to provide a compact format. For these reasons, all data in pdf can be compressed, and the peculiarity of it is that different types of compression are applied to different types of information, more suitable for these types of data: JPEG, RLE, CCITT, ZIP.
PCX– raster image format. pcx files use a standard color palette, this format has been extended to store 24-bit images. This format is hardware dependent. Designed to store information in a file in the same form as in the video card. To combine this format with older programs, support for the EGA mode of the video controller is required. The compression algorithm is fast and takes up a small amount of memory, but is not very efficient and is not suitable for compressing photographs and detailed computer graphics.
ICO– This format is designed for storing file icons. Ico files can be any size, but the most commonly used icons are those with sides of 16, 32 and 48 pixels. Icons with sizes of 24, 40, 60, 72, 92, 108, 128, 256 pixels are also used. Icon data is usually not compressed. Icons come in True Color, High Color, or with a clearly fixed palette. By its structure ICO files are closest to the BMP format, but differ from bmp in the presence of a mask applied to the background using the bitwise “AND” operation, which makes it possible to implement transparency.
Exclusive OR overlaying the main image can even invert pixels where the background was not masked. And already with Windows XP, 32-bit icons began to be supported - each pixel corresponds to 24-bit color plus an 8-bit alpha channel, which allows for partial transparency of 256 levels. Using the alpha channel, it is also possible to display the icon with smooth edges and also with a shadow, combined with different backgrounds, the icon mask in this case is ignored.
CDR is a vector format image or drawing created using CorelDRAW. This format was developed by Corel for use in its own software products companies. CDR images are not supported by many graphics editors. But this is not a problem, the file can be easily exported using the same CorelDRAW to more common image formats. Images created in CorelDRAW and with the CDR extension can also be opened in Corel Paint Shop Pro. For best compatibility, Corel recommends saving files in an earlier version of CorelDRAW CDR format. CDR files of the tenth and earlier versions can be opened using Adobe Illustrator.
A.I. is a vector image format, the name of which comes from the abbreviation of the name of the vector editor AdobeIllustrator. Supported by almost everyone graphic programs, which are somehow related to vector graphics. Ai is one of the best middlemen for transferring an image from one editor to another. A distinctive and very important feature of the format is its greatest stability and compatibility with PostScript, which is of great value for publishing houses of printing products.
RAW– this is a data format containing raw information (or processed to a minimal extent), created directly by incoming information from the matrix of a camera (video camera, etc.). This format denotes not only photo data, but also the original audio or video data. This format stores all information about the file and has greater potential for photo processing than the JPG format. RAW preserves the highest possible quality. Data in RAW files can be uncompressed, losslessly compressed, or lossily compressed.
RAW files from a number of camera manufacturers have their own extension format, such as Canon - CR2, Nikon - NEF. Many others have the DNG format proposed by Adobe, these are companies such as Leica, Hasselblad, Samsung, Pentax, Ricoh. If Photoshop does not have a raw camera for your camera, then the files will not open; it was created for these purposes by Adobe.
SVG– Scalable Vector Graphics format. The format was created by W3C. According to the specification, it is designed to describe two-dimensional vector and mixed vector/raster graphics in XML. Includes three types of objects: shapes, images, and text. Supports still, animated and interactive graphics. You can create and edit both in text editors by editing the code, and in any graphic editor for vector graphics (Adobe Illustrator, Inkscape, CorelDRAW, Corel SVG Viewer). SVG is an open standard and is not proprietary.
Of the advantages SVG format can be highlighted. Scalability without loss of image quality. Text in SVG is text, not an image, so it can be selected, copied, and indexed by search engines (when used on a website). The interactivity of the graphics makes it possible to attach your own events to each element. Availability of using raster graphics within a document. Animation that is implemented in SVG using the SMIL language. Compatible with CSS, it allows you to set object properties such as color, background, transparency, etc. SVG easily integrates with HTML and XHTML documents. Reducing the number of HTTP requests. Small file weight compared to raster graphics.
Vector formatsFiles vector format are especially useful for storing linear elements (lines and polygons), as well as elements that can be decomposed into simple geometric objects (such as text). Vector files do not contain pixel values, but mathematical descriptions of image elements. Based on mathematical descriptions of graphic forms (lines, curves, splines), the visualization program constructs an image.
Vector files are structurally simpler than most raster files and are usually organized as data streams.
Examples of the most common vector formats are AutoCAD DXF and Microsoft SYLK.
WMF. This is a vector format used by Windows graphics programs. This format is used to transfer vector images via the clipboard to Windows environment. This format is accepted by almost all programs that work with vector graphics. This format cannot be used for raster images. Disadvantages: color distortion and failure to save a number of parameters that are set for images in graphics programs.
AI. Internal format Illustrator programs. Can open Photoshop program and besides, this format is supported by all programs related to vector graphics. This format is the best remedy when transferring vector images from one program to another. Raster graphic elements are lost in most cases when transmitted via AI format.
CDR. This is the internal format of the Corel Draw program. This format is very popular, as is the software package itself. Many programs can import vector files into Corel Draw formats. The CDR format also contains raster graphic objects. This format uses compression, and different compression is applied to vector and raster files.
Metafile formats
Metafiles can store both raster and vector data. The simplest metafiles resemble vector files; they contain the language or syntax for defining vector data elements, but may also include a raster representation of the image. Metafiles are often used to transport raster and vector data between hardware platforms, as well as to move images between software platforms.The most common metafile formats are WPG, Macintosh PICT and CGM.