Three tests: 7-zip and WinRAR

Today, I found a document and downloaded it online. Is a 7z compressed package, more than 70 m. After I decompress the package with WinRAR, I found that there were more than 600 m. I was surprised that the compression ratio was so high. No. I need to know why the 7z format is so compressed. First of all, I use WinRAR to compress it for more than 110 m. It seems that 7z is so powerful that I am ignorant, only WinRAR. Now I have seen 7z, and I am very open to my eyes. Searching 7z related information online is still an open source software, which reminds me of the trouble of WinRAR cracking. In addition, some people have compared these two types of software (7z has a higher compression ratio and compression ratio than WinRAR). The reference is as follows.

Source: http://www.pconline.com.cn/pcedu/pingce/0603/771310.html
Author: King

In the evaluation of the previous compression software, we tested the fraudulent 1.4 mboffice 2007 file, and had a profound understanding of the File compression of KGB and WinRAR. Finally, WinRAR is better than KGB.

In the comments of this article, I have seen that many of my friends recommend 7-zip, and even many others say better than WinRAR. Is that true?

Everything depends on the facts. We have prepared three targeted tests to see who is better. WinRAR adopts the "best" compression ratio and the "extreme compression" Mode for 7-zip during the test.

Evaluation environment:

Hardware environment:	CPU: Intel Pentium 4 630,300 0 MHz (15x200) memory: 1 GB Motherboard name: ASUS P5GPL-X. Display Card: NVIDIA geforce 6600 (256 MB) Sound Card: ad1986a @ intel 82801fb ich6-high definition Audio Controller [C-0]
Network Environment:	M optical fiber broadband
Software environment:	Operating System: Microsoft Windows XP Professional SP2 Browser: Internet Explorer 6.0.2900.2180 (IE 6.0 SP2) DirectX version: 4.09.000000904 (DirectX 9.0c)

[Download WinRAR] | [Download 7-zip]

1. Massive text compression experiment

I have prepared 100 *. TXT plain text files are used for testing. The total size is 14.7 MB, the size after 7-zip compression is 6.323 MB, and the size After WinRAR compression is 7.179 MB. For more information, see the table below.

7-zip Compression

WinRAR Compression

Software/Project	Compression time	Compressed volume	Compression rate
7-zip	23 seconds	6.323 MB	40%
WinRAR	9 seconds	7.179 MB	46%

We can see that WinRAR has many advantages in the compression time, and the larger the gap between the more files and the time of 7-zip compression. However, from the aspect of compression ratio, 7-Zip is obviously dominant. Although it takes up to 23 seconds to compress, it makes the file smaller.

In terms of compression ratio, 7-Zip is higher than WinRAR

Slightly inferior to 7-zip

2. lossy image format Compression Experiment

In terms of image compression, I have selected 200 JPG images totaling 50.7mb for testing. We all know that JPG is an image file that has been compressed. Generally, the compression software can not reduce the size, therefore, I have a hunch that this step is not very big.

The compression ratio is not big compared with WinRAR.

After compression, the volume is only small.

Software/Project	Compression time	Compressed volume	Compression rate
7-zip	46 seconds	50.844 MB	95%
WinRAR	36 seconds	50.906 MB	95%

Sure enough, the two softwares are unable to maintain the JPG compression ratio and stay at 95%. But take a closer look at the compressed size, but there are still tiny differences. In general, 7-Zip is smaller than WinRAR.

3. ISO image file decompression Experiment

The purpose of this experiment is to see the difference between the decompression speed of 7-zip and WinRAR. According to the above compression time, winRAR is expected to be a little faster than 7-zip before the competition, but it is better to win or lose based on actual results.

7-zip unzipping faster compression time

WinRAR lost to 7-zip in the speed comparison test

Software/Project	Decompression required
7-zip	3 minutes 55 seconds
WinRAR	4 minutes 14 seconds

The evaluation results are surprising. In the above tests, WinRAR, which has been ahead of the 7-zip speed, actually lost a lot, reaching more than four minutes, I tested it three more times and the results were the same. In this evaluation, WinRAR's unzipping speed is less than 7-zip.

Two supported formats for software compression/decompression are provided:

Software/Project	Number of compression formats that can be generated	Number of decompressed formats
7-zip	5 types	15 types
WinRAR	2 types	14 types

Conclusion: After a targeted evaluation of compression and decompression, I think that the decompression and compression ratio of 7-Zip is superior to that of WinRAR, and it is easy to operate, basically, it is not the same as WinRAR. But again, the 7-zip compression format WinRAR can be solved, but it cannot be created.

7-zip cannot be created in this format. After all, in addition to the decompression operations, common users sometimes need to compress the files into the RAR format, after all, this is the most popular compression format on the Internet.

While 7-zip does not have the preparation function of RAR format, it can also uncompress the RAR package. So here I think it is better to use WinRAR with the general trend. As for 7-zip, it is also very good, as the chief alternative software for compression/decompression.