Nowadays, many people are thinking about how the process of compression to save space on your hard drive, it is one of the most effective use of storage space in any storage device.Quite often, the modern users who are faced with the lack of free space on your drive, it is necessary to remove any data in an attempt to free the right place, while more advanced users often use data compression to reduce its volume.
However, many do not even know the name of the compression process information, not to mention what the algorithms and the use of which gives each of them.
Needless to compress data?
Data compression is important enough for today and it is necessary for any user.Of course, nowadays almost everyone can buy advanced data storage, providing the ability to use a sufficiently large amount of free space, and equipped with high-speed channels broadcast information.
However, it must be properly understood that with the passage of time also increases the amount of data that must be transmitted.And if just ten years ago, the standard for conventional film was considered to be the volume of 700 MB, today movies made in HD-quality, may have a volume equal to several tens of gigabytes, not to mention how much space is occupied by high-quality picturesformat Blu-ray.
When data compression is necessary?
Of course, one should not expect that the process of compression will bring you many benefits, but there is a certain number of situations in which some of the methods of data compression is extremely useful, and even necessary:
- transmission of certain documents via e-mail.This is especially true in situations where you need to pass the information on a large scale, using a variety of mobile devices.
- Often the process of data compression to reduce the space it occupied is used in the publication of certain data on various sites, when you want to save the traffic;
- saving space on your hard disk in the case where there is no way to replace or add the new means of data storage.In particular, the most common situation is that when there are certain limitations in the available budget, but it does not have enough free disk space.
course, in addition to the above, there are a lot of different situations in which you may need to process data compression in order to reduce its volume, but these are by far the most common.
How can compress the data?
Today, there are a variety of data compression techniques, but they all fall into two basic groups - a certain loss of compression and lossless compression.
Using the latter group of methods is relevant when the data should be restored with an extremely high precision, up to one bit.This approach is only relevant in the case when the compression is performed from an text document.
It should be noted that in some situations there is no need as much accurate restoration of the compressed data so provides for the use of such algorithms in which the data compression on the disc is performed with certain losses.The advantage of lossy compression is that this technology is much more easy to implement, and provides the highest possible degree of archiving.
compression algorithms with losses providing an order of magnitude better compression while maintaining sufficient quality of the information.In most cases, the use of such algorithms is carried out to compress the analog data, such as all kinds of images or sounds.In such situations, the extracted files may be quite different from the original information, but to the human eye or ear, they almost indistinguishable.
Lossless compression algorithms
lossless compression provides the most accurate data recovery, excluding any loss of compressed files.However, to properly understand the fact that in this case is provided not so effective compression files.
In addition, there is a certain number of universal methods by which the process is carried out effective data compression to reduce the space occupied by it.In general, you can select all three major technologies:
- Conversion flow.In this case, the description of the new incoming information is not compressed by the already processed files is not carried out any calculation of probability, and the encoding symbols is performed based on only those files that have already been subjected to certain treatments.
- Statistical compression.The process of data compression to reduce the occupied disk space on it is distributed into two sub-categories - and block adaptive methods.Adaptive option is to calculate the probability for new files of information that is being processed in the encoding process.In particular, such methods should also include a variety of options for adaptive algorithms Shannon-Fano and Huffman.A block algorithm provides separate vyschityvanie each block of information, followed by adding to the compressed block.
- Unit conversion.Incoming information is divided into several blocks, and subsequently takes a holistic transformation.It should be said that the specific methods, particularly those based on permutation several blocks may ultimately lead to significant reduction in the volume of the compressible media.However, to properly understand that after this treatment, eventually there is a significant improvement in data structures, so that the conduct of subsequent compression algorithms is carried out through the other much more easily and quickly.
compression when copying
One of the most important components of the backup is a device by which to move the desired user information.The more data you will move, the more you need to surround the device will use.However, if you will be a process of data compression, then the problem of lack of space is unlikely to remain relevant for you.
Why do it?
Possibility of compression backup can significantly reduce the time it takes to copy the necessary files, and thus achieve an effective reduction of free space on the drive.In other words, when using compression information will be copied much more compact and fast, and you can save your money and finances, which were needed to buy more storage volume.Among other things, carrying out data compression, you can also cut the time it takes for transportation of all data on the server, or copy them over the network.
Data compression for backup can be performed in one or several files - in this case, everything will depend on what kind of program do you use and what information is compressed.
choosing the utility, be sure to take a look at how your program can compress data.It depends on the type of information, whereby the compression efficiency of text documents can be more than 90%, while the compression of images will be effective for not more than 5%.