To the question of various abbreviations and obscure technical terms. DPI - what is it? This reduction is known to designers, computer scientists, those who at least once worked with the image. Gamers with their cool special mice have also heard about this term. Now we will try to deal with this abbreviation.
Options
If you ask the Internet about DPI what it is and where it is applied, you will get several answers at once. After all, there are three decipherments of this reduction:
- Deep Packet Inspection is a provider tool that collects statistics, checks network packet filters and their contents.
- Discounted Profitability Index is an economic term that is responsible for return on investment.
- Dots per inch - from English it is translated as "dots per inch".
It is the latter option that we will consider.
Resolution
Speaking specifically about DPI, it becomes clear that it means only a unit of measurement. But why? It turns out to find out the resolution of the image and this abbreviation is applied.
Resolution in itself is an indicator that indicates the number of dots (pixels) per unit area. Most often, this indicator is applicable to digital-type images, but it is used in the work with granulation of film, photo paper, etc.
So, if you need to save the data in a graphic file with the desired scale and print it all out, then most likely DPI will come to the rescue. This value will indicate the number of dots per inch. If you have a resolution of 300 dpi, respectively, it equals 300 dots per inch.
Example
Another example is to understand how this quantity works. Suppose your picture has a resolution of 350 dpi. You need to transfer it to 10 by 10 cm paper. Translated into inches, you get 3.9 x 3.9 inches. To understand what size of the source image is needed, it is necessary to multiply 3.9 by 300. So we get 1170 x 1170 pixels. With this indicator, the picture quality will be acceptable.
Application
Now more about where and how DPI is applied. What is it, we have already figured out. A value is used to indicate resolution. We need the latter when displaying graphic data on a flat medium.
You can also find this value in the specifications for the printer. 600 to 450 dpi can be specified. So it becomes clear that the devices are endowed with a resolution that is horizontally equal to 600 points, and vertically 450 points. In this case, we take a square of 1 by 1 inch for the area.
If we talk about the printer, then often this figure is compared with PPI. These two quantities mean the same thing. Use if you need to mix inks for printing. Then 1 dpi will be equal to 1 ppi. If the device does not need to mix ink, then this formula will look different. The index N is used, which indicates the number of colors used for printing. Then dpi will be equal to ppi times that number, that is, the index N.
This calculation is the main advantage for inkjet printers. Unlike photomachines, string devices have a higher DPI value with an equal PPI value. Because they expose more points to convey one pixel.
Other indicators
Image DPI is not the only resolution. As we already learned, there is a relationship with other similar indicators. So, in printers, a raster dot is represented by many small dots. They are called flash. The number of such flashes per inch is indicated by DPI. The number of raster dots that hide in this flash by one inch is PPI. Accordingly, if the ratio of the two indicators is greater, the image is better.
There is another indicator - this is LPI. The value indicates the number of lines per inch. This resolution characterizes the operation of a laser printer. In this case, the inch is not represented by a dot, as before, but by a line. That is, to be more precise in the wording, then LPI is the number of lines per linear inch.
Another value is represented by the acronym SPI. It shows the number of elementary spots. The indicator is quite complex and not so often used in photo printing. But in general, it is used for printing gradients. And if the PPI indicates the end result, then the SPI is part of the process. Interestingly, in general, both indicators under equal conditions have the same value.
Gaming mice
But it turns out that this is not all DPI information. What is it, we broadly understood. For what is applied, also figured out. But they missed one thing. The fact is that the value is often found on packages with gaming mice. It is difficult to connect the information we received earlier with the parameters of the manipulator. But you can try.
The fact is that dpi in the controller is decrypted in the same way, but it has a slightly different understanding. To be precise, for a mouse this indicator is better to decipher as dots of cursor montion per inch. That is the number of cursor points per inch. Next to this value is cpi. It roughly means the same, and it would be logical to apply precisely this reduction. But in general, both one and the second value convey the number of steps that the manipulator goes through by 1 inch.
And it is worthwhile to understand that we are talking about the movement of the mouse, not the cursor. In this case, movement is interpreted as a step, and step as a signal. If the dpi is large, then the device moves smoothly.
Marketing?
In theory, it turns out that this indicator, which is shouted from advertising booklets and packaging, is more of a marketing ploy. The fact is that few people know, but for this very speed we must not forget about the speed of polling the port. It is known that at the moment the highest indicator is 1000 Hz. You might think that if the mouse passes 2 inches in one second, then this figure will double. In fact, it turns out that it is still impossible to cross the threshold of 1000 Hz. So then what is the advantage of this value in manipulators?
DPI is an indicator that changes the speed at which the cursor moves on the display. And it does the most high-quality in the case of high-resolution screens. It is logical that if the display is large, then the mouse should walk a distance proportional to the diagonal of the monitor. Therefore, this value is important only for players and those who work with graphics. For them, a figure of 1600 dpi is considered acceptable.
For other users who have a screen smaller than 1600x1200, 800 dpi will be enough. This value is average today. If the monitor is 1200x800, then a mouse with a resolution of 400-500 dpi will be sufficient.
conclusions
It becomes clear that DPI is a value that is more familiar to designers, those who work with graphics and printing. This is a resolution that allows you to determine the number of dots per inch when displaying an image on a flat media. If we are talking about a mouse, then DPI in this case shows the mouse movement per inch.
If you have a gaming mouse, then the question of how to configure DPI should not arise, because usually there is a special button on the case to adjust the resolution. In some cases, you can configure through software. If you have a regular mouse, but you want to adjust its speed, then it will be enough to go into the settings on the PC and set the slider to the desired level.