Posted by PTravel on 01/12/83 11:53

"Martin Heffels" <youwishyouwouldknow@nottellinya.com> wrote in message
news:4pi6b214jg30157u3eob15oj5n5q0jva7l@4ax.com...
> On Tue, 11 Jul 2006 05:39:33 GMT, "PTravel" <ptravel@travelersvideo.com>
> wrote:
>
>>Actually, I did miss it but I've looked at it now. And, of course, it's
>>not
>>an answer to my question, which is "how often does an uncorrectable error
>>occur"? You say, it's likely 99.99% of the time it's correctable. I
>>say,
>>I haven't seen the statistic anywhere, so it might be 9% or it might be
>>99.99999999%.
>
> You can answer that question based on your own experience of course. What
> these numbers tell you is that there is a lot happenening that you don't
> even notice, repaired unnoticeable to you, but noticeable to the player.

And what the numbers don't tell me are how many of them are uncorrectable.
Is sticking to the subject really that difficult?


>
>>Sorry, but that's a cop out. Again, the context of this discussion is
>>whether DV experiences generational loss. All your (and Martin's)
>>discussion has been theoretical and unquantified.
>
> Yes, for an end-user, this seems to be a perfect world, where nothing
> happens, but for an engineer who is designing tapes, and players, it is a
> nightmare and they will tell you different.
> Think about it: 100 drop-outs per minute. They won't all be correcteable,

How do you know? That's a rhetorical question, by the way. The answer is,
you don't and the Sony sheet that you posted doesn't provide the answer.


> so repair will take place by copying/interpolating data. Seeing the amoun,
> I really start to believe that every copy you make, you loose data and
> thus
> you loose a generation.

You believe a lot of things. I'm not interested in your beliefs. I'm
interested facts. So far, you've presented none.


>
>>This is no different than
>>Martin's mpeg2 rants, when he claims that mpeg is "capable" of better
>>video
>>performance than DV-codec.
>
> Ha! You haven't forgotten that one.

Since you never fail to raise it, it's hard not to.

> Still haven't delved into this deeper?

No need. Once more: D-25 video has better quality than DVD-compliant mpeg.
Period.

> Many more articles written about this with the arrival of HDV which tells
> you I am right.

Irrelevant to the discussion. We're not talking about HDV, but the
comparison between D-25 and mpeg2.

>
>>Of course, since the discussion is always in the
>>context of whether a consumer DVD camcorder will produce better video than
>>a
>>comparable miniDV camcorder, his answer, while technically correct, is
>>misleading and inapplicable to the question. Similarly, here, the
>>question
>>was whether DV experiences generational loss in the context of making dubs
>>and as compared to analog video. Without quantifying the uncorrectable
>>data
>>rate, claiming that "mitigated" data correction (for lack of a better
>>term)
>>equates to generational loss is, while technically accurate, misleading
>>and
>>inapplicable to the question.
>
> Typical lawyer answer: not guilty until proved ;-)

Typical non-lawyer misunderstanding of what that means, which is this: the
state bears the burden of proving, beyond a reasonable doubt, the existence
of facts that compel a finding of guilt. You and Richard keep insisting
that that D-25 results in generational loss because of the existence of
uncorrectable errors. I've asked you to quantify the number of
uncorrectable errors, since a miniscule amount is meaningless for the
purpose of this discussion, which is: will D-25 result in more generational
loss than SuperBeta?

You haven't met your burden of proof because (1) you've provided no evidence
but, more importantly, (2) you don't know.

This is the sum total of your argument;

" Think about it: 100 drop-outs per minute. They won't all be correcteable,
so repair will take place by copying/interpolating data. so repair will take
place by copying/interpolating data. Seeing the amount, I really start to
believe that every copy you make, you loose data and thus you loose a
generation."

Entirely predicated upon speculation, with no foundation in fact. All
right, here's some more speculation. I'll take Richard's 8 bits per 10
minute error guestimate, resulting in a reliability for D-25 of 99.99999975%

So, 100 errors per minute * 30 minutes = 3000 errors, .00000025% of which
are uncorrectable and result in data loss. That's a total of 0.00075 errors
per 30 minutes, or 0.0015 errors per hour of video. Put another way, you'd
have to shoot 666 hours of video before you hit one uncorrectable error.

Using Richard's assumption, as well as yours.

Now, me -- I don't like to assume. I like hard data.

Let me know if you get some.

>

>
>>If the uncorrectable data rate is sufficiently high, then describing the
>>effect as generational loss is accurate. If the rate is miniscule, then
>>it
>>is not. Unless I know the rate, I can't tell which it is.
>
> I will keep looking for some more data.

Fine. Then we could talk. Who knows, you may even be right.

> But maybe I am wasting my time,
> because you haven't even bothered to follow the links I posted in my
> previous message.

I missed the link, though, as it turns out, it wasn't relevant to anything
in this discussion.

> So whatever I find, I will keep for myself, and maybe
> share it with mr Crowley, and Craig the Tapeguy, and let you live in your
> perfect world, so you don't have to worry too much. It might distract you
> from shooting your nice city-footage ;-)

Yes, feel free to be the Guardian of Secrets. That's not why you post on
Usenet anyway, is it?


>
>>That means that 99.99999975% of the time, the data is accurate, i.e. a
>>bit-for-bit copy.
>
> That is not a bit-for-bit copy, because that would be 100%!

I'll tell you one thing that it's not, though: "generational loss."

>
> cheers
>
> -martin-
> --
> "If he can he'll smile 'cos he's a Royal Crocodile."

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