Audio Coding Part 6
OGG encoding
An audio codec called Ogg Vorbis appeared on the Internet, known as the MP3 killer! What is the origin of Ogg Vorbis? OGG is the project name of a large multimedia development program, which will involve the development of video and audio encoding. The whole purpose of the OGG project plan is to provide a completely free media encoding solution for anyone! OGG’s belief is: OPEN! FREE! The word Vorbis is the name of a “playboy” character in the fantasy novel “Small Gods” by Terry Platjat. This term became the official name for audio encoding in the OGG project. At present, Vorbis has been successfully developed and an encoder has been developed.
Ogg Vorbis is a high quality audio coding scheme. Official data shows that Ogg Vorbis can achieve better sound quality than MP3 at relatively low data rates. Ogg Vorbis is also much more advanced than MP3, which was successfully developed in the 1990s. It can support multiple channels, what does this mean? This means that Ogg Vorbis can encode all channels with the support of SACD, DTSCD, DVD AUDIO ripping software (currently there is no such software), instead of MP3 it can only encode 2 channels. The rise of multi-channel music has brought revolutionary changes in music appreciation, especially when enjoying the symphony, it will bring more presence. This revolutionary change cannot be adapted to MP3.
Like MP3, Ogg Vorbis is a flexible and open audio codec that allows for significant sound quality adjustments and further algorithm improvements once the codec has been fixed. Therefore, your sound quality will get better and better. Like MP3, Ogg Vorbis is more like an audio coding framework, which can be continually improved by introducing new technologies. Like MP3, OGG also supports VBR.
MPC encoding
MPC is another impressive and powerful player. Its popularization process is very discreet and there is no complicated backstory. She only has one purpose for her looks, smaller size and better sound quality! MPC was previously known as MP+, and it’s obvious who it’s targeting. However, anyone who has used this code will be impressed by its excellent sound quality.
mp3PRO encoding
On June 14, 2001, Thomson Multimedia SA and Fraunhofer Institute released a new version of music format on June 14 named mp3PRO, which is an improved scheme based on mp3 encoding technology is quite attractive in features announced by the officer. According to various information, mp3PRO is not a completely new format, it is an improvement based on traditional mp3 encoding technology, and its biggest technical feature is SBR (Spectral Band Replication), which is a new audio encoding enhancement algorithm. Provides the ability to improve speech and audio encoding performance at low bit rates. This approach increases audio bandwidth or improves encoding efficiency at a specific bit rate. The biggest advantage of SBR is that it can achieve very efficient encoding at low data rates. Unlike traditional encoding technology, SBR is more like a post-processing technology, so the quality of the decoder algorithm directly affects the sound quality. . The high frequency is actually produced by the decoder (player), and the SBR encoded data is more like a set of commands that produces high frequency, or a guide signal source, which is kind of the way it works. We can see that mp3PRO is actually a mixed data stream encoding of mp3 signal stream and SBR signal stream. Relevant information shows that SBR technology can improve high-frequency sound quality with little data traffic by about 30%. We don’t care how this 30% is obtained, but it can be predicted in advance that this improvement can make the 64kbps mp3 reach 128kbps. The sound quality level of mp3 (note: under the same encoding conditions, the increase in data rate is not proportional to the increase in sound quality, at least in the human ear), which is comparable to mp3 PRO official 64kbps, which is comparable to 128kbps mp3 The propaganda is basically consistent.
