How am I going to be able to use my VHS recorders when digital is forced on us?

In message , Paul Bird
writes
"Paul" wrote in message
...

When he replies at length instead of just to say he's "snowed under at
present", then, I will.

He replied, at last!

And it's a real hoot :-)

Quote
The main problem is the quality of the codec to convert to a format suitable
for DVD. I know of many people who do this, even Anglia do it, but all use
software codec's and this is the down fall. Some of the more expensive
software
codecs work quite well, but a hardware codec is best (costs lots!).

So that is why camcorders with DV-in cost "lots" since they use hardware
codecs. I think not :-)

Have a
go
and see how you get on, the codec in DVD architect is average but does not
like
noisy source pictures which is exactly what you get from domestic mini DV!

Wrong ! DVD Architect does NOT employ a codec. Vegas does, and allows
you to use any codec you like. Vegas happens to come with the
MainConcept MPEG-2 codec for video, and the Dolby Digital AC-3 codec for
sound. The resulting files are the ones used in DVD Architect.

The sony camera which writes straight to DVD, I think is not a good way to
go
because the maximum bit rate for a DVD is 10Mbit, and this will define the
source quality as rather low. To edit this will mean converting to 25Mbit if
using Vegas Video, then back to 10Mbit which will further reduce quality.

Mini DV is 25Mbit,

Mbit what? Per mile? Per yard? Per minute? The last time I looked,
miniDV is 3.4Mb/sec.

a rate used for broadcast now (broadcast used to be
144Mbit!) and gives good domestic quality. also there are many edit packages
that use native DV data (i.e. 25Mbit).

AFAIK there is no such thing as "native DV".

The point here is, that if the material is to be edited, it is best to start
at
a higher bit rate at source,

But VHS doesn't have a bit rate ! It is analogue :-)

than the destination bit rate. When creating
cross
fades, the mathematics used greatly benefits from having a good source
resolution, as, inevitably, data gets lost as the two scenes merge.

Again this shows a lack of basic understanding. Cross fades are achieved
(on the outgoing fade) by lowering the gamma, and on the incoming fade
by increasing the gamma.

Unquote

Paul

I'm sorry Paul, but this is an absolute load of twaddle.

The only thing he is correct about is the suggestion to use as high a
resolution at source as possible, but since the source is VHS analogue,
you can only start with about 240 lines of resolution so his observation
has no significance in this context.

Though not relevant in the context of the question, MiniDV will provide
a source of about 510 lines of resolution. But when rendered
(transcoded) to MPEG-2 you'll get about 420 lines of resolution.

--
Tony Morgan
http://www.camcord.info

"Tony Morgan" wrote in message
...
In message , Paul Bird
writes
"Paul" wrote in message
...

snip

Mini DV is 25Mbit,

Mbit what? Per mile? Per yard? Per minute? The last time I looked,
miniDV is 3.4Mb/sec.


Sounds like he is talking about DVPro, not MiniDV. Which would
follow, as IIRC, his information is coming from (so he says) a
'broadcast engineer'.

In message ws.net,
":::Jerry::::" writes

"Tony Morgan" wrote in message
...
In message , Paul Bird
writes
"Paul" wrote in message
...

snip

Mini DV is 25Mbit,

Mbit what? Per mile? Per yard? Per minute? The last time I looked,
miniDV is 3.4Mb/sec.


Sounds like he is talking about DVPro, not MiniDV. Which would
follow, as IIRC, his information is coming from (so he says) a
'broadcast engineer'.

If he was what he claims to be, I would think that he would know the
difference between DVPro and miniDV. Similarly, I wouldn't have expected
him to get confused between analogue and digital.

Still, I'm relieved that he doesn't claim to be a brain surgeon :-)

--
Tony Morgan
http://www.camcord.info

"Tony Morgan" wrote in message
...
In message
ws.net,
":::Jerry::::" writes

"Tony Morgan" wrote in message
...
In message , Paul
Bird
writes
"Paul" wrote in message
...

snip

Mini DV is 25Mbit,

Mbit what? Per mile? Per yard? Per minute? The last time I
looked,
miniDV is 3.4Mb/sec.


Sounds like he is talking about DVPro, not MiniDV. Which would
follow, as IIRC, his information is coming from (so he says) a
'broadcast engineer'.

If he was what he claims to be, I would think that he would know
the
difference between DVPro and miniDV. Similarly, I wouldn't have
expected
him to get confused between analogue and digital.

Still, I'm relieved that he doesn't claim to be a brain surgeon :-)


Read what is said Tony g, I didn't say he was a broadcast engineer
(and I don't think he has either), IIRC his brother in-law works for
(again IIRC) for one of the ITV companies. The fact he *isn't* a
broadcast engineer is exactly why he seems to be a bit mixed up...
:~)

On Sun, 7 Aug 2005 02:10:51 +0100, Tony Morgan
wrote:

In message , Paul Bird
writes
[SNIP]
Mini DV is 25Mbit,

Mbit what? Per mile? Per yard? Per minute? The last time I looked,
miniDV is 3.4Mb/sec.


It is my understanding that MiniDV uses 25Mbits per sec for the
video rate. Certainly many docs that I have seen make mention of this
figure. (I believe SMPTE 314 is relevant here.)

Regards,
Harry.


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

In message , Harry Broomhall
writes
On Sun, 7 Aug 2005 02:10:51 +0100, Tony Morgan
wrote:

In message , Paul Bird
writes
[SNIP]
Mini DV is 25Mbit,

Mbit what? Per mile? Per yard? Per minute? The last time I looked,
miniDV is 3.4Mb/sec.


It is my understanding that MiniDV uses 25Mbits per sec for the
video rate. Certainly many docs that I have seen make mention of this
figure. (I believe SMPTE 314 is relevant here.)

Here's how you can discover what it *really* is:

1. Fill a 1 hour miniDV cassette with shot(s) - you can
simply switch to record with a tape and come back
an hour or two later.

2. Capture, using you favourite editor.

3. Move the clip (or clips) into the timeline and note the
number of minutes of video (call that 'X')..

4. Note the size of the AVI file (call that 'Y').

5. Divide 'Y' by (X * 60). This gives you the number of Mb
per second.

I think that you'll find it to be very close to 3.4Mb/s. And *very* far
removed from 25Mb/s. As Jerry suggested, the 25Mb/s figure is perhaps
DVPro, and not miniDV. Apples and oranges are *not* the same.

--
Tony Morgan
http://www.camcord.info

I think that you'll find it to be very close to 3.4Mb/s. And *very* far
removed from 25Mb/s. As Jerry suggested, the 25Mb/s figure is perhaps
DVPro, and not miniDV. Apples and oranges are *not* the same.

I think you're confusing bits with bytes here. MiniDV is 25Mb/s (Megabits
per second) which is approximately 3.6MB/s (Megabytes per second). The
resultant DV file is sometimes referred to as DV25. DVCPro can use 50Mb/s.

See http://en.wikipedia.org/wiki/DV

"DB" wrote in message
...
big snip

MiniDV is 25Mb/s (Megabits
per second) which is approximately 3.6MB/s (Megabytes per second).
The
resultant DV file is sometimes referred to as DV25. DVCPro can use
50Mb/s.


You are of course quite correct.

"Tony Morgan" wrote in message
It is my understanding that MiniDV uses 25Mbits per sec for the
video rate. Certainly many docs that I have seen make mention of this
figure. (I believe SMPTE 314 is relevant here.)

Here's how you can discover what it *really* is:

1. Fill a 1 hour miniDV cassette with shot(s) - you can
simply switch to record with a tape and come back
an hour or two later.

2. Capture, using you favourite editor.

3. Move the clip (or clips) into the timeline and note the
number of minutes of video (call that 'X')..

4. Note the size of the AVI file (call that 'Y').

5. Divide 'Y' by (X * 60). This gives you the number of Mb
per second.

Seems like a lot of hard work to me, Tony.

Instead, just stick a five-second colour clip on your timeline and save it
to disk as a AVI (DV type 1).

B = (S - C) / D

Where B is the bitrate for the clip (the value you are trying to work out),
S is the size of the file on disk (in bits), C is a constant (header
information for the disc-based AVI file not present in data on a tape) and D
is the duration of the clip, in seconds.

The larger the clip, the less significant the value of C in calculating the
bitrate.

It's something of an oversimplification, because the value of C changes as
the file gets bigger. I've got an Excel spreadsheet somewhere that (to an
extent) can work out the byte-accurate filesize of a PAL DV AVI if you put
in the duration of the video accurate to 1/25th sec. I ran out of patience
trying to work out when C increases, but there seems to be a pattern to it
in terms of the magnitude of the increase.