Raster graphics. Formats of raster graphics. Disadvantages of raster graphics

Computer graphics imperceptibly, but firmly entered our everyday life. It has long ceased to be the lot of the elect. Each time, transferring photos from a digital camera to a computer or simply clicking on the "save" button to add to the collection of your favorite picture, you work with computer graphics.

Should I waste time on theory?

Knowing the basics of how the image method works, will do you a good job. Extensions after the file name will cease to be for you some kind of magic abracadabra, but will start to supply important information. You can consciously decide which images to compress better, so as not to litter the hard disk space, and choose the right way to do it.

Editing your own photos will also move from the state of the "scientific poke method" to a whole new level. And for some, innocent fun with images on the screen gradually passed and into a fairly lucrative work.

The difference between raster and vector graphics

At the moment, the computer environment mainly uses vector and raster graphics. They are radically different from one another in the way they encode information.

It's no secret that all data in the computer is written using binary code. Thus, any information, whether text, picture or sound, is encrypted in a certain way. In order to save a vector image, it is divided into elementary geometric shapes, which, in turn, are described by the simplest mathematical formulas. Thus, for example, the letter "and" for a graphic editor will be described by two parallel segments of a given length, which are connected by a line at an angle of 45 degrees.

The bitmap image is broken in a different way. The computer splits the picture into a set of points called pixels, and remembers the color and location of each pixel.

Advantages and disadvantages

If you work with a vector drawing, then theoretically you can increase it to infinity. And the quality of the image is in no way reflected. Since the parameters are given in the form of geometric formulas, the computer simply recycles them and fills all the voids with the right colors. As a result, you have a clear image.

Disadvantages of raster graphics lie precisely in the fact that compression (which in the vast majority of cases takes place while saving a file) can significantly damage the quality. Appears so-called granularity. However, it is the raster graphics used in complex images. In vector drawings you can create only very simple pictures. So now we will focus on where the raster graphics are applied.

Areas of use

Raster images ideally convey the contents of the scanned objects. With their help you can work with halftones and a smooth transition of color. Photographs taken with a digital camera also use only raster images. Also this format serves as an irreplaceable tool in the field of web design.

Bitmap graphics formats

Recall that information about the image in our case is encoded using points. The unit of measurement in this encoding is the pixel. This is the smallest point that can not be divided either in terms of size or color.

The number of these points per given unit of area is called the resolution. On a high resolution image (a large number of individual dots) we see a clear pattern and smooth color transitions. However, in case the resolution is small, the quality of the image can suffer greatly (after all, the computer simply displays the number of points in its memory and stretches them to the requested size).

The file format can be conditionally compared with the language. In order to transmit the same information in different languages, you will need a different number of letters, sounds and words. Also in most cases, the grammatical construction will also differ. And "translators" from these "languages" in our computers are specialized programs that either "read" it, or convert it into the right format.

The main difference between formats is the way information is stored. Consider the most common.

BMP

This is one of the pioneers. When it was developed, raster graphics were, you can say, at the very roots of its existence. The creators did not bother much and programmed the BMP to sequentially memorize each pixel. In fact, it's just copying, but with some color loss, since only 256 colors are available in BMP format.

TIFF

It is quite cumbersome on the scale of digital storage, but it is simply indispensable when printing information. Unlike BMP, it supports the ability to compress (compress) information. And for this you can use not one, but several different algorithms. However, if you do not work in the printing industry or at least some publishing house, you will not need a serious capacity of this format.

GIF

This is more approximate to the real use (for non-specialists) format. He is especially famous for the possibility of using an animation sequence. Computer graphics, made in this format, also allows you to create semi-transparent images. However, you will not be able to transfer smooth flow of colors. Most often, raster graphics in GIF format can be seen in web design. It is compatible with all platforms and compact enough to compress information, which is an important factor in the speed of opening Internet pages.

JPEG

The most popular format. And it is quite deserved. Any graphical editors of raster graphics no doubt support this format. It was designed for a specific purpose - to get rid of the limitations imposed by the compression of GIF files. The compression algorithm in this format reaches a factor of 100 units. This is a big indicator. However, such compression still has its drawbacks - some data loss occurs, and it is possible that the saved image will become somewhat blurry. Since this format simply throws away information that it considers insignificant, there is always a risk of distortion of some details.

JPEG 2000

Improved version of the earlier version. Information about the image is compressed even more compactly, and the quality loss is much less. Most often this format is used to store photos on the hard drive of the computer and on the Internet. However, it should be remembered that if you repeatedly save the same image in JPEG or JPEG 2000 formats, it will always lose pieces of information, and eventually you will get a significantly distorted picture compared to the original.

PNG

Significantly improved in quality fellow GIF. Keeping literally all the advantages of his predecessor, he is deprived of his shortcomings. Used for both image editing and web page design. In addition, PNG, in contrast to GIF, is officially available.

PSD

Raster graphics in PSD format are processed exclusively in Adobe Photoshop. This is the internal package of this program. It supports work with layers of the edited image.

CDR

This is also an internal package for the Corel DRAW raster graphics program . Typically, this program is used by graphic designers to create images from scratch. But the editing function is undoubtedly supported.

Editors of raster graphics

And now a little about the programs that work with editing images.

The most popular among users at the moment is the program Adobe Photoshop, in the common people called simply "Photoshop". This development, in fact, monopolized the work with raster images in the environment of design specialists. However, this program is paid and it costs not so little. Therefore, the development of other companies began to appear. Some of them have already been widely used.

As for the "Photoshop", it did not affect its popularity. The interface of this program is quite simple, and in a variety of video courses and tutorials there is no shortage.

In "Photoshop" you can not only make a collage of photos or add to the image the built-in effects. The simplest functions of this program can be mastered very quickly, and this will open the door for an unrestrained flight of fantasy. You can correct the flaws of the exterior, adjust the color gamut, change the background and many more.

Graphical editor of GIMP

As for free programs, then you can safely recommend GIMP. This graphic editor can easily press the untwisted "Photoshop". It perfectly copes with all the tasks necessary for editing raster images, and has some initial functions for working with vector graphics.

The GIMP program allows you to take photos more saturated and lively, it easily removes unnecessary elements from the image and can be used to prepare professional design projects. Computer graphics created with this program, looks natural and seamlessly fits into the overall picture.

Graphic editor Corel DRAW

It would be wrong to bypass Corel's products. In Corel DRAW, you can easily work with both raster and vector images. The possibilities of this tool are so numerous that the study of the program Corel DRAW is included in the compulsory course of preparation of graphic designers in colleges.

This program is also paid, and the arsenal of its products is replenished with an enviable regularity. But, despite the tremendous opportunities that this graphical editor provides to the user, its intuitive interface makes the workflow a pleasure.

Free image editors

And just a few words about alternative programs for image editing. In most cases, they perfectly cope with the requests of the average user, and the places and resources on your computer are taken several times less. And to work with them is by and large easier, since you will not be overwhelmed by the need to choose among all sorts of functions, the purpose of which remains unclear.

If you like unusual and mostly comic photos, try using the program Funny Photo Maker. There you will find many original frames and funny visual effects.

For more serious works Picasa will do. This editor is sharpened for use in computer networks. Its new features will allow you to even more easily create your pages in social networks. And the built-in effects for editing do not disappoint even the sophisticated specialist.

Another interesting program is Paint.NET. It is very similar in features and capabilities to Adobe Photoshop. And the tools used in Paint.NET can seriously compete with the said commercial counterpart.