AirPlay
The technology of broadcasting audio and video signals through a Wi-Fi connection. Widely used in Apple electronics, the media centre with AirPlay will make it easy to duplicate a “picture” on a TV, for example, from an iPhone or iPad. The main disadvantage of this technology compared to similar Miracast is the need for a local network with a wireless router.
Optical output
A variation of the SP/DIF audio interface that uses a TOSLINK fibre optic cable. Like the coaxial connector,
the optical output uses a digital data transfer format and can work with multi-channel audio. At the same time, optical fibre requires rather delicate handling, but it is absolutely insensitive to electrical interference.
CPU frequency
The clock speed of the CPU installed in the media centre.
On the technical side, the higher this indicator, the faster the processor works and the higher, accordingly, the overall system performance. At the same time, the CPU performance depends, in addition to the frequency itself, on a number of factors — architecture, number of cores, special design features, etc.; and the actual speed of the entire system is affected by performance of components other than the processor. In addition, manufacturers usually select processors in such a way that their computing power is guaranteed to be enough for all the features claimed for a media centre. Therefore, in this case, the CPU frequency is more of a reference parameter (and partly an advertising indicator that demonstrates the advanced specifications of the device), rather than practically significant for buyer.
Video decoders
Codec — from the phrase "Encoder-DECoder" — in this case is the format used for encoding digital video during storage/transmission and decoding during playback (without encoding, video data would take up an unjustifiably large amount of space). Do not confuse this parameter with the format of video files: different files of the same format can be encoded with different codecs, and if the corresponding codec is not supported by the player, video playback will be impossible, even if the file format itself corresponds to the capabilities of the device. And in models with online TV support (see "Features") this nuance also determines compatibility with a specific broadcast: the general format of the broadcast is indicated by the codec used for this.
In general, modern devices usually have quite extensive sets of codecs (one of the most advanced for 2021 is
H.265), and there are usually no problems with video playback; in extreme cases, you can use special programs for transcoding files. As for specific codecs, detailed data on them can be found in special sources, but with standard use of media players, such details are not needed.
Audio decoders
The set of audio codecs supported by the device
Codec — from the phrase "Encoder-DEcoder" — in this case, the format used for encoding and compressing sound in digital form during storage/transmission and decoding — during playback (digital sound is basically impossible without encoding, and compression allows to reduce the amount of data). Information about supported codecs is relevant primarily for assessing whether the player will be able to work with sound in a particular video file. The fact is that even in video files of the same format (see below), sound can be compressed by different codecs; and if the player supports the file format, but does not support the codec, sound playback will become impossible.
Theoretically, these rules are also relevant for audio files and online broadcasts (all formats — TV, video, audio). However, in fact, when working with such content, you can ignore codec data. So, for each audio file format, usually, its own standard codec is used, and file type support automatically means codec support. Broadcasts usually use generally accepted audio decoders like MPEG-1 or MPEG-2, which are practically guaranteed to be supported by any modern player designed for such broadcasts.
As for specific codecs, detailed information on them can be found in special sources, however, with the standard use of devices, such details are usually not needed.
