[mythtv-users] Dish Network and MythTV

[Michael T. Dean]

On 11/30/05 20:11, Chris Ribe wrote:

> I don't know much about dish and myth, but I think I can answer your 
> MPEG4 questions.

Note, that the MPEG-4 in question is actually MPEG-4 AVC (Advanced Video 
Coding), a.k.a. H.264.  This is the same format that is required by both 
HD-DVD and BluRay players* and allows you to easily encode video using 
1/2 the bitrate required for MPEG-2 with similar picture quality.

*BluRay is a standard promoted by Sony and it requires, among other 
formats, H.264 support.  Sony has been pushing the idea of H.264 on 
BluRay as the format that allows the most content per disc (more than 
any other CODEC on BluRay and more even than H.264 on HD-DVD).  Although 
in a true "biting the other hand that feeds it" moment, Sony Pictures 
just announced they're going to put MPEG-2--the same CODEC used for 
standard def DVD's and ATSC--on BluRay disks.  :)  
http://www.engadget.com/entry/1234000293070178/

> When:  Sometime in the next 12 months.

> Rationale:  Better compression is need to fit hundreds of HD channels 
> in currently available bandwidth.  MPEG4 playback hardware is cheap 
> enough to satisfy the bean counters. 

Specifically, dedicated MPEG-4 playback hardware is cheap.  However, 
using general-purpose processors (i.e. Intel/AMD) for decoding requires 
not-so-cheap hardware (you can't buy an x86-based processor that can 
decode 1080i H.264, so top-of-the-line will get you closest and 
top-of-the-line is around $1000/CPU).

> Etc.:  Current hardware can't decode MPEG4 signals, but the vast 
> majority of current hardware can't decode MPEG2 HD either.  The SD -> 
> HD changeover (which is well under way, despite the caterwauling by 
> some Cassandras on this list) presents a one time opportunity for the 
> sat. companies to upgrade their tech simultaneously.

Specifically, current TV's can't decode MPEG-4 and most current TV's 
can't decode MPEG-2 (although all HDTV's--those with ATSC tuners, as 
opposed to HD-Ready TV's, which need a separate tuner--can decode 
MPEG-2).  However, all DISH and DirecTV receivers can decode MPEG-2, as 
that's the format the satellite companies are using to transmit the 
video (both standard- and high-definition channels).

So, in summary, when DISH/DirecTV go to MPEG-4, you won't be any closer 
to getting HDTV over satellite because it will still require a satellite 
receiver for decrypting their stream and the satellite receiver will 
output decoded video, which we're still a long way from being able to 
encode in real-time at HDTV resolutions (even using MPEG-2 format, which 
is significantly easier to encode than H.264).

Mike