File extention is the file format of a certain file you save. You do this by putting a .*** at the end of your file name. This changes the type of file it gets saved as. Some examples are .png , .jpeg , .exe , .dmg and .txt. These file types are used for different things and you need to use a specific one depending on what your making it for. Some people use filename extentions to trick people into thinking its a harmless file where infact it contains a virus or malicous software.
File Compression There are two different types of file compression which are "lossless" and "lossy". These are two ways to compress a file in different ways
Lossless
Lossless compression is a form of compression which you don't lose any information in the process. This has become more and more advanced as technology has. An example of this is when an image has area's of pixels the same colour, the data can be read as 100 blue pixels instead or blue pixel blue pixel.
Lossy
Lossy compression is the opposite to lossless as you lose data and quality whereas in lossless you don't. The benifit to lossy though is that the loss is acceptable. Depending on the file changes the amount of data can be lost with still able to have decent quality. An example of this is in JPEG images it works by rounding off the less important bits. In audio you use speech compression which is used for CD ripping.
No comments:
Post a Comment