Posted by Jan Panteltje on 11/22/06 11:48

On a sunny day (Wed, 22 Nov 2006 09:58:25 +0000) it happened Spex
<No.spam@ta.com> wrote in
<45641f42$0$8759$ed2619ec@ptn-nntp-reader02.plus.net>:

>Jan Panteltje wrote:
>> On a sunny day (21 Nov 2006 14:14:07 -0800) it happened "Mike Kujbida"
>> <kujfam@xplornet.com> wrote in
>> <1164147247.491244.232250@k70g2000cwa.googlegroups.com>:
>>
>>> Jan Panteltje wrote:
>>>> On a sunny day (21 Nov 2006 13:38:13 -0800) it happened "Mike Kujbida"
>>>> <kujfam@xplornet.com> wrote in
>>>> <1164145093.775293.55280@h48g2000cwc.googlegroups.com>:
>>>>
>>>>> The downconverted HD will look much better than straight SD because
>>>>> you're starting with a higher quality to begin with.
>>>> This is not correct, 'aliasing' will occur.
>>>> For aliasing, in the simplest form, think how to put 10 dots on a line in 7.
>>>>
>>>>
>>>> 1 2 3 4 5 6 7 8 9 0
>>>>
>>>> a b c d e f g
>>>>
>>>> Never quite fits now does it?
>>>
>>> Sorry Jan but my own personal experience (as well as that of several
>>> users on various Vegas forums) tells me otherwise.
>>> I borrowed a friend's Z1 one day and did some test shoots of water
>>> flowing down a stream into a pond. I locked the camera on a tripod and
>>> shot in both SD & HDV. I then brought this footage into Vegas 3 ways,
>>> SD, HDV & HDV downconverted. I also rendered the HDV footage to
>>> SD,again in Vegas.
>>> I then looked closely at all 4 shots on my reference monitor (JVC
>>> TM-H150CGU - 750 line SD monitor). To my eyes, the downconverted HDV
>>> (either way) looked better than the straight SD footage.
>>>
>>> Mike
>>
>> Well I cannot argue with [anybodies] experience.
>> Maybe there are other factors at work, but the theory stands.
>
>Your theory is ill thought out.
>
>You are overlooking the fact that the people who write NLE editing and
>compression software know a little bit more about their subject than
>many give them credit for?
>
>The images are not subjected to a rudimentary resize and compression
>algorithm as your example implies. The images are in fact resized
>generally with sub-pixel accuracy, anti-aliased, then sent to the
>compressor.

And that makes these better then the original format?
But no more fits in the original format!

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