WeTek Play2 - 4K PVR - HD Audio - Dual Boot - Specs & Reviews
(2016-05-08, 10:49)noggin Wrote:
(2016-05-08, 10:23)medulin Wrote: mmm.. so I'm bit confused :-D
I made that question since I have read that from January 2017 the TVs sold in Italy will must have DVBT2 H.265/HEVC tuners.. even if I think transmissions in H265 won't start before 2019-2020 :-P

That's a 'commercial' use of the word 'tuner' rather than a 'technical'. If you are buying an IDTV (Integrated Digital TV) then the 'tuner' is often used to describe the 'tuner+demodulator+codec', which will be DVB-T2 (tuner+demodulator) and HEVC (decoder/playback).

In a computer context the DVB-T2 'tuner' is really only the 'tuner+demodulator' section, the 'codec' is separate. When you buy a USB, PCI-E, Ethernet etc. based 'tuner' for a computer you are only buying the 'tuner+demodulator' (*), the 'codec' is handled by the computer (either with software decode or hardware acceleration) As a result the 'tuner' has no codec in it, and so isn't H264, H265, MPEG2 etc., those duties are part of the computer that is playing back the video.

You can broadcast MPEG2, H264 and H265 on DVB-T or DVB-T2. In many countries DVB-T tuners are used for SD MPEG2, SD H264 and HD H264. (France, Norway, Ireland etc.) I had no problems tuning the BBC HD tests in 2006 (which were also DVB-T HD H264) using an existing DVB-T USB 2.0 tuner I already owned. These were test H264 services before any hardware was being sold for H264 reception.

This is because all that a PC (**) tuner+demodulator does is tune to the RF frequency carrying the services and demodulate the signals to create an MPEG2 transport stream - which contains video, audio, EPG, subtitle, digital text services all as separate streams (aka PIDS). Some devices will filter out some of these services as requested by the PC (to reduce the data bandwidth and avoid carrying PIDs that aren't needed. Others will send the whole multiplex (which can be 40Mbs+ for a DVB-T2 mux) Whether a PC can display the audio and video streams is purely a function of the video functionality of the PC NOT the tuner+demodulator.

When looking at DVB solutions for PC, the video codec in the computer is the key thing, the tuner has none. (Though sometimes specs describe tuners as 'HD' - that isn't really true...)

(*) Some very early 'full' PCI DVB-S and DVB-T tuners actually had their own codecs and video outputs on the PCI card and didn't use the PC video output at all. This was because in the early days even MPEG2 SD was tricky to do on a PC! You plugged a Composite or SCART connector for your display into the tuner card... The days of these are long gone. Also these days some Ethernet or WiFI based tuner devices also provide streaming for mobile devices, which sometimes involve transcoding to a codec that the mobile device can handle (so the 'tuner' includes a codec to allow decode and recode)

(**) PC = computer playback solution, including the Kodi section of the Play 2S.

thanks! you helped me to understand! :-)
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Messages In This Thread
RE: WeTek's ** New ** AMLogic Mediaplayers - 2016 - Play2 - Streamer - HUB - by medulin - 2016-05-08, 10:57


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