| Topic | Description |
| Extension | .opus |
| Details | |
| Description | The format has been created by IETF community for online broadcasting and is being used for lossy compression of audio data. It provides with excellent quality of sound and very good compression level due to the technology of dynamically adjusted streaming. Being a key audio codec of Skype, OPUS is based on the Skype message-transfer algorithms. As a container, they use .ogg extension. |
| Actions | |
| Details | The format uses CELT and SILK codecs, which allow easy change of bitrate within the range of 6-510 Kbit/s. That is why it has gained prevalence in video chats and video conferences, as well as IP translations. |
| Developed By | IETF |
| Mime Type | audio/opus audio/ogg |
| Topic | Description |
| Extension | .mp3 |
| Details | |
| Description | MP3 is a digital music format which allows CD tracks to be reduced to around a tenth of their normal size without a significant loss of quality. MP3 gets rid of a lot of the information recorded in a song that our ears are not able to hear and then uses complex algorithms to reduce the file size. This then enables you to get hundreds of songs on to a CD and it also has opened up a new market over the internet - the download market as download times have been significantly reduced. MP3 is a digital format for storage of audio files designed by MPEG programmers. It is one of the most required codecs for digital coding. The format is widely used in various file-sharing sites for evaluation downloading. With this format, it is possible to compress CD tracks up to 1/10 of their original size while maintaining high playback quality. Overtones, which cannot be perceived by a human ear, are removed. Complex algorithms allow for smaller size of tracks. As a result, one compact disk can contain several hundred songs. MP3 is compatible with all most popular operating systems and supported by the most of modern DVD-players and music systems. |
| Actions | |
| Details | The MP3 format is a lossy format. That means that an MP3 file does not contain 100% of the original audio information. Instead, MP3 files use perceptual coding. In other words, that means it removes the information that your ear doesn't notice thereby making the file smaller. The reason lossy formats are used over RAW is that RAW audio files are too large to travel over the internet at any great speed. By using lossy formats it enables even dial up users to download mp3 files at a reasonable speed. RAW file formats generally require 176,000 bytes per second compared to a lossy format which requires 17,600. The difference is massive and so are the download times. Prior to MP3 introduction, MPEG-1 had been widely used. That format contained not only audio data, but images as well. MP3 breaks an audio file into parts of the same length. When the processing is over, each part is packed into its own frame. It involves the technology of spectral limit that requires a continuous input signal to provide the use of two adjacent frames. When spectral deleting is over, the file is to be compressed with mathematic methods. If necessary, compression rate can be changed, even inside the same frame. Files of 128 kbit/s have 11-fold compression. Further reduction of the file size will lead to significant deterioration in sound quality. |
| Developed By | Moving Picture Experts Group |
| Mime Type | audio/mpeg audio/mp3 audio/mpeg3 audio/mpg audio/x-mpeg audio/x-mpeg-3 audio/x-mpegaudio audio/x-mpg audio/x-mp3 |