Gif, jpeg and png format. Their characteristics and application
Each file has its own format, indicated after the dot in its name (by default it is hidden). So, for Word files it is used docx (or doc in old versions), for video recordings it is AVI, ASF, 3gp, etc. For images, others are created. We will consider them.
This extension was created in 1977 by Israeli experts in information theory, and initially had the abbreviation LZ (Lempel-Ziv). And in 1984, the algorithm was changed, the compression process was improved. After this procedure, LZ changed its name to LZW. After 7 years, CompuServe changed the algorithm for transferring a graphic image between computers.
After all the changes, the format of GIF images appeared, and JPEG can compete with it. But CompuServe went further - it decided to earn some extra money and only allowed licensed people to use the GIF format. Things reached the point that companies had to create another format that does not require a license, and they began to use PNG. But nowadays GIF is more and more often used, and for free.For example, in social networks, not only smiles, but also funny animated pictures that are able to convey the mood of an interlocutor are used to transmit emotions.
This format, as described above, was used as an alternative to paid GIF and more complex TIFF. It also surpasses the animation format in compression quality and the number of colors from 1-bit to 48-bit and extension to two pixels. PNG format was created by PNG Development Group. He was presented at the Useter conference in January 1995. After it, four versions of PNG were developed. It was originally called PBF. A little later got its final name. It was positioned as a tool for editing graphics and working on the Internet.
PNG is suitable for three main types of images: halftone images, color indexed images and full color images. Another advantage is that, unlike JPEG, compression is lossless. And he also has the optional support for the alpha channel, the possibility of gamma correction and two-dimensional interlaced scanning. And another advantage is that pictures in PNG format look saturated.
However, this format has disadvantages.One of them is the inability to multi-image and animation. A separate MNG format was developed for moving pictures and was published in mid-1999.
This extension received its name from the Joint Photographic Experts Group and ISO. Today it is a format that is able to compress an image well enough.
This extension was created to work with pictures and photographs containing real natural phenomena or elements of human life (tree, sunset, chair, computer, etc.).
But such a format is completely unsuitable for compressing drawings of pictures with text or characters; the JPEG format is not suitable for them. PNG or GIF will be much better able to handle this feature.
We looked at the three most popular formats that we see all the time: these are PNG format, GIF and JPEG. They learned about the advantages and disadvantages of each of them.
Now that you know a little more about them, you probably will not convert the picture with animals into PNG format or you won’t wrestle with why it’s impossible to save an animated image in GIF.