Whats the point of Freeview?

On Mon, 20 Oct 2008 22:51:22 +0100, Roderick Stewart wrote:

Does this mean that anything failing to live up to this cannot be
described as "hi-fi"?

I think that you will find that audio enthusiasts regard the standard
as not being stringent enough to define "high fidelity"; more so
today with the much higher quality components which are available
than was the case in the 1960s and 1970s which was the working
period of the original standard.

On Tue, 21 Oct 2008 01:21:26 +0200, J G Miller wrote:

I think that you will find that audio enthusiasts regard the standard
as not being stringent enough to define "high fidelity";

ISTR that that was the case when it was first published.

--
Alan White
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:- http://windycroft.gt-britain.co.uk/weather
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In article , Alan White wrote:
I think that you will find that audio enthusiasts regard the standard
as not being stringent enough to define "high fidelity";

ISTR that that was the case when it was first published.

And yet there is, and has been for a long time, plenty of equipment in the
shops that is sold as "hi-fi" and can make a very pleasing representation
of musical sounds, even to quite critical listeners, regardless of the
numbers in an official document that nobody reads.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

In article ,
Java Jive wrote:
The definition of HiFi, though it was never actually
standardised as such, would have been a flat frequency response
between about 15-23,000Hz

Where did that come from? 20-20k is more usual. Although it's a rare
loudspeaker/room combination that will go that low. And even rarer to find
musical information at the extreme ends of the spectrum. So for much you
could chop an octave off both ends.

--
*Remember not to forget that which you do not need to know.*

Dave Plowman London SW
To e-mail, change noise into sound.

But are you starting with the entire bandwidth previously available to
analogue TV?

On Mon, 20 Oct 2008 22:12:59 +0100, Stuart Clark
wrote:

How about we look at it in the other direction? What sort of picture
could we fit in the available bandwidth?

On Tue, 21 Oct 2008 10:19:18 +0100, Roderick Stewart wrote:
And yet there is, and has been for a long time, plenty of equipment
in the shops that is sold as "hi-fi" and can make a very pleasing
representation of musical sounds, even to quite critical listeners

Stereograms and music centres?

On 2008-10-20, Java Jive wrote:
keeping everything else 'perfect', the difference in bandwidth between
using lossy compression and lossless compression is the only absolute,
non-subjective measure (that I can think of) of what has actually been
thrown away.

But it doesn't tell you anything.
Converting 1 hour of uncompressed video to
a) a 700MB MPEG1 (VideoCD) file, and
b) a 700MB MPGE4 file
have by your definition both 'thrown away' the same amount of information,
as the output bandwidth to transmit them would be the same, but the MPEG4
file will look massively better than the MPEG1 file.

On 21 Oct 2008 16:45:51 GMT, Paul Murray wrote:

On 2008-10-20, Java Jive wrote:
keeping everything else 'perfect', the difference in bandwidth between
using lossy compression and lossless compression is the only absolute,
non-subjective measure (that I can think of) of what has actually been
thrown away.

But it doesn't tell you anything.

Well it does, but I agree it's not perfect ...

Converting 1 hour of uncompressed video to
a) a 700MB MPEG1 (VideoCD) file, and
b) a 700MB MPGE4 file
have by your definition both 'thrown away' the same amount of information,
as the output bandwidth to transmit them would be the same, but the MPEG4
file will look massively better than the MPEG1 file.

Which is one very good reason why it's not perfect. The only answer
would be to find differing yardsticks of lossless compression for
comparison, one 'equivalent' to MPEG1 and the other 'equivalent' to
MPEG4. Or perhaps a better approach would be if there was a switch in
the codec to choose between lossless and lossy compression, then you
would be comparing the outputs of essentially the same codec.

But every idea that I can think of seems to have the problem of
finding anything suitable that actually exists! Meanwhile, I think we
are probably just going to have to stick with measuring that
appallingly low fraction of the original signal that is actually
received ...

In article , J G Miller wrote:
On Tue, 21 Oct 2008 10:19:18 +0100, Roderick Stewart wrote:
And yet there is, and has been for a long time, plenty of equipment
in the shops that is sold as "hi-fi" and can make a very pleasing
representation of musical sounds, even to quite critical listeners

Stereograms and music centres?

If they're sold as "hi-fi", who's to say they're not, and on what grounds?

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

Java Jive wrote:
But are you starting with the entire bandwidth previously available to
analogue TV?


Currently we have 5 full power analogue channels, plus 6 lower powered
digital muxes.

Assuming we can convert all 11 channels to t2, that is still only about
330Mbps in total - enough for a single uncompressed SDI signal and
little else.

DVDs are only 10Mbps. Is that not high enough quality?

At that level you could fit 3 channels per mux, giving you 18 over the
6. Switching to H.264 would give you more.

Even though we have channels 21 - 69 available (49 x 30 = 1.5Gbps) in
reality you can only use a small proportion of them from any particular
site, so you don't interfere with other services (either abroad or at
other transmitters within the UK).