How to Compress Files when Zip or Rar using 7Zip? : You have downloaded the repacked games. When you download them you have a file like 4GB but after extracting you have seen that the game becomes about 20GB. How to do this magic? Today we will talk about that.
This is done using a technique called Compression. With the advent of the Internet and even earlier storage problems, computer scientists wanted a way to store and transfer large files. If you understand this problem, let’s say we went to download a movie, then if it is about 10GB in size, it’s a mess. Our money goes and hours go by. This is where compression comes into play.
7Zip Compression We mainly divide into two parts.
Lossy Compression
Here’s how it works: Reduce the quality of the content and delete the non-essential bits to reduce the file size. The best example of a file format compressed in this way is the JPEG format. We know that in JPEG you save a photo / image. When JPEG files are compressed, the bits that show the subtle colors of the image are deleted. Then you can reduce the size of the file.
You have a simple example of this JPEG compression work. The images you send in WhatsApp are sent only after a Lossy compression. As you can see, there is a reduction in quality. This is to minimize the data usage of the person taking the image as well as your phone. Recently, a feature has been added to WhatsApp that allows you to send without any loss of quality.
Compression algorithms are also used in this compression technique. They are not too complicated. But in lossless compression complex algorithms are used.
Lossless Compression
Rar and 7zip files are good examples of lossless compression. When we compress these, the size decreases, and when we extract again, our files can be taken care of as before.
How to do this magic? This problem has been asked by computer scientists before. “How do we reduce the size of a file without reducing it?” The world’s greatest mathematicians have come up with solutions to this problem. As a result, various algorithms came up. They are very complex. But, let us illustrate this with a very simple example.
Let’s take the word below.
1) aaddddooooononoooo
There are repeating letters in this word. We write them like this.
2) a2d4o5n2o5
This is written as a2 because there are two letters a and d4 because there are 4 letters d and so on. As you can see, the first word is more likely to be stored and the second word less likely to be stored. The second word came when the first word was compressed. Can we extract the second word and make the first word again? A: That’s how this has to be explained simply.
Then you will ask in which world there are such repetitive words. Yes true, no such words. That is why in an article like this, files are compressed using mathematical methods that are difficult to explain. It takes some time to compress and extract files. (I saw a bar in Winrar fill up a bit) I think the work is clear now.
You now know that Lossless compression is a mathematical magic.
Compression is a very important concept. Without this, downloading not only movies and games but also songs from the internet would have been a very bitter experience. Not only that, our hard disk and phone memory could have been filled quickly
7Zip Quick Video Tutorial from youtube.
Source : 7Zip
