Cable Forum - Tivo mpeg 2 or 4?

Page 1 of 2

Show 100 post(s) from this thread on one page

Cable Forum (https://www.cableforum.uk/board/index.php)

- Virgin Media TV Service (https://www.cableforum.uk/board/forumdisplay.php?f=11)

- - Tivo mpeg 2 or 4? (https://www.cableforum.uk/board/showthread.php?t=33673241)

gadge

20-12-2010 15:40

Tivo mpeg 2 or 4?

As the title when we get our hands on it is it as the title says mpeg 2 or 4?.

Andrewcrawford23

20-12-2010 16:32

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by gadge (Post 35140739)

As the title when we get our hands on it is it as the title says mpeg 2 or 4?.

mpeg 4 fro what i haev read in the specs thinkt hat why oyu can record more than you would on SA with 1tb

nialli

20-12-2010 16:35

Re: Tivo mpeg 2 or 4?

How great is the difference between Mpeg2 and Mpeg4? If an hour of Mpeg2 is 2Gb for SD, what is an hour of Mpeg4? Is the difference the same for HD recordings (one hour = 8Gb)?

gadge

20-12-2010 16:41

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by nialli (Post 35140758)

How great is the difference between Mpeg2 and Mpeg4? If an hour of Mpeg2 is 2Gb for SD, what is an hour of Mpeg4? Is the difference the same for HD recordings (one hour = 8Gb)?

Well at the moment on our samsung v+ we have,

steptoe and son ride again,
two ronnies xmas special,
the desent hd,

and there is 66hrs left.

Andrewcrawford23

20-12-2010 16:51

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by gadge (Post 35140761)

Well at the moment on our samsung v+ we have,

steptoe and son ride again,
two ronnies xmas special,
the desent hd,

and there is 66hrs left.

samsung although has mpeg4 is using it for recording it turned off but can be turned on in th future or it record mroe than teh SA box so they hve problem marketing one boxc at 160 and another at 200+ hours cant remember the difference

Stuart

20-12-2010 17:03

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by gadge (Post 35140761)

Well at the moment on our samsung v+ we have,

steptoe and son ride again,
two ronnies xmas special,
the desent hd,

and there is 66hrs left.

AFAIK, all the currently used cable boxes do NOT reencode or recompress the data they recieve. When any current v+ "records" a programme or film, it merely saves the data stream sent to it from VM's head end.

The advantage of MP4 is (very simply put) that it can reproduce the same quality as Mp2 at a given bitrate, but using around half that bitrate. Will we see any increase in quality when VM switch to MP4? Probably not, They'll be looking at the fact that they can cram twice as many channels in.

We will have the advantage that the apparent storage capacity on the Tivo will be a lot higher than it would otherwise.

devilincarnate

20-12-2010 17:27

Re: Tivo mpeg 2 or 4?

From what i have read the box is backwards compatable so will be able to switch from the current MPEG that they use to the other ( trying to find the quote for this )

Stuart

20-12-2010 17:55

Re: Tivo mpeg 2 or 4?

It will, but if they are only sending MP2, I doubt the box will re-encode the video.

Andrewcrawford23

20-12-2010 20:02

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by Stuart (Post 35140808)

It will, but if they are only sending MP2, I doubt the box will re-encode the video.

i believ teh tivo box will record in mpeg4 ie compress the mpeg2 signal i could be wrong but i am pretty sure that how t ogin ot work and that why it can record mroe than current v+ box if they had 1tb drive

mersey70

20-12-2010 20:14

Re: Tivo mpeg 2 or 4?

I thought the next generation of cable compression is DVB-C2 which isn't the same as MPEG4, much the same as DVB-T2 as used here isn't the same as MPEG4 DTT in Ireland.

Do any cable operators worldwide actually use MPEG4, I though DVB-C is mainly used but DVB-C2 is just being rolled out in Europe.

Stuart

20-12-2010 20:31

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by Andrewcrawford23 (Post 35140875)

I'd be surprised if it did. The quality loss would be significant and would give Sky a huge selling point.

---------- Post added at 21:31 ---------- Previous post was at 21:18 ----------

Quote:

Originally Posted by mersey70 (Post 35140881)

You are getting compression (MPEG2, MPEG4) and data structure mixed up. DVB-C, DVB-C2, DVB-T etc define the structure of the data being sent. This data can be compressed using either MPEG 2 or MPEG 4.

Think of it this way. When you download something from the Internet, it is usually carried using TCP/IP packets (not always, but most downloads are). The hardware carrying the packets has no specific "knowledge" of what it is sending. That data can be an image, a web page, an application or whatever. The TCP/IP protocol does not care what is sent, merely that the data it has is sent to the correct address. DVB-C2 is like TCP/IP in this respect.

The compression defines what data is sent. That is sorted out by what happens to be at the end of the connection, be it a computer or cable box.

mersey70

20-12-2010 21:08

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by Stuart (Post 35140885)

I'd be surprised if it did. The quality loss would be significant and would give Sky a huge selling point.

---------- Post added at 21:31 ---------- Previous post was at 21:18 ----------

You are getting compression (MPEG2, MPEG4) and data structure mixed up. DVB-C, DVB-C2, DVB-T etc define the structure of the data being sent. This data can be compressed using either MPEG 2 or MPEG 4.

Think of it this way. When you download something from the Internet, it is usually carried using TCP/IP packets (not always, but most downloads are). The hardware carrying the packets has no specific "knowledge" of what it is sending. That data can be an image, a web page, an application or whatever. The TCP/IP protocol does not care what is sent, merely that the data it has is sent to the correct address. DVB-C2 is like TCP/IP in this respect.

The compression defines what data is sent. That is sorted out by what happens to be at the end of the connection, be it a computer or cable box.

I won't pretend to understand all that but do any cable operators currently use MPEG4?

Some of the big cable operators of Europe are pushing for DVB-C2 which supposedly is 30% more efficient than DVB-C, VM have said they do not have any plans to use it though.

http://www.broadbandtvnews.com/2009/...-dvb-c2-ibc09/

Stuart

20-12-2010 21:42

Re: Tivo mpeg 2 or 4?

Quote:

Originally Posted by mersey70 (Post 35140898)

DVB-C and C2 define how the data is formatted. They do not define what that data is. The current Cable system uses DVB-C to carry MPEG2 compressed data. As I understand it, there is no reason it cannot carry MPEG 4 compressed data.

And yes, some cable companies do use MPEG 4..

---------- Post added at 22:42 ---------- Previous post was at 22:40 ----------

Quote:

Originally Posted by mersey70 (Post 35140898)

DVB-C and C2 define how the data is formatted. They do not define what that data is. The current Cable system uses DVB-C to carry MPEG2 compressed data. As I understand it, there is no reason it cannot carry MPEG 4 compressed data.

And yes, some cable companies do use MPEG 4..

It's unlikely that the new Tivo box will have enough processing power required to encode MPEG 4.

Stephen

21-12-2010 15:14

Re: Tivo mpeg 2 or 4?

It will probably be compatible with both just like the Samsing V+ is but VM only broadcast on MPEG2 currently.

IMO anyway.

gadge

21-12-2010 15:35

Re: Tivo mpeg 2 or 4?

Thanks for all the replys i asked because when we were with ntl their version of the tv drive was to be mpeg 4 but when merged with telewest they used the mpeg 2 version.

All times are GMT. The time now is 16:32.

Page 1 of 2

Show 100 post(s) from this thread on one page