Movies - DivX
Compression Rate
Data Compressors |
Original Size (bytes) |
Compressed Size (bytes) |
Space Saved (bytes) |
WinRAR |
200,228,230 |
184,531,230 |
15,697,000 |
WinRK |
200,228,230 |
185,131,077 |
15,097,153 |
SBC Archiver |
200,228,230 |
185,782,591 |
14,445,639 |
WinAce |
200,228,230 |
188,206,132 |
12,022,098 |
7-Zip |
200,228,230 |
188,511,794 |
11,716,436 |
Squeez |
200,228,230 |
189,635,601 |
10,592,629 |
bzip2 |
200,228,230 |
191,225,633 |
9,002,597 |
WinZip |
200,228,230 |
191,929,653 |
8,298,577 |
gzip |
200,228,230 |
192,211,984 |
8,016,246 |
ARJ32 |
200,228,230 |
192,502,937 |
7,725,293 |
StuffIt |
200,228,230 |
200,238,053 |
-9,823 |
In this test of DivX video files, we can see just how hard it is to compress media files that are already compressed. Even the best compressor, WinRAR, only managed a compression rate of 7.8%, with a space saving of almost 15.7MB.
WinRK and SBC Archiver were close behind. Both achieved compression rates of 7.5% and 7.2% respectively. The worst compressor was StuffIt. As we saw with MP3 files, it totally refused to compress this fileset, creating an archive that was slightly bigger than the original.
Compression Speed
Data Compressors |
Original Size (bytes) |
Time (s) |
Speed (KB/s) |
StuffIt |
200,228,230 |
4.49 |
44594.3 |
gzip |
200,228,230 |
15.23 |
13147.0 |
WinZip |
200,228,230 |
17.76 |
11274.1 |
ARJ32 |
200,228,230 |
17.88 |
11198.4 |
bzip2 |
200,228,230 |
48.68 |
4113.2 |
7-Zip |
200,228,230 |
61.38 |
3262.1 |
SBC Archiver |
200,228,230 |
92.32 |
2168.8 |
Squeez |
200,228,230 |
105.40 |
1899.7 |
WinRAR |
200,228,230 |
114.68 |
1746.0 |
WinAce |
200,228,230 |
187.42 |
1068.3 |
WinRK |
200,228,230 |
464.76 |
430.8 |
The speed leader was naturally StuffIt. It only took 4.5 seconds to crunch through 200MB of DivX files because all it did was pack the files together with no compression whatsoever.
The fastest compressors that actually did any real compression work were gzip, WinZip and ARJ32. They all compressed the fileset in about 15-18 seconds, giving them a compression speed of 11-13MB/s. The other compressors were much slower, with WinRK stupendously slow. It took almost 8 minutes to complete the test.
Compression Efficiency
The compression efficiency rating is a simple way to evaluate the efficiency of each data compressor. This way, we can see which compressor can save the most space in the least time.
Please note that a higher efficiency rating does not mean the compressor is better. It just means the compressor has a better compression-to-speed ratio. A more efficient compressor is, of course, always more desirable than a less efficient one.
The most efficient data compressors when it comes to DivX video clips were the trio of gzip, WinZip and ARJ32. Their tremendously fast compression speed, coupled with their moderately good compression rate allowed them to outperform the other compressors in efficiency. They were over 2.2X to 2.7X more efficient than the next most efficient compressors, 7-Zip and bzip2.
The most inefficient compressors were, naturally, WinRK and StuffIt. WinRK because of its extremely slow compression speed, and StuffIt because of its total refusal to compress the fileset.