Re: Saving a .wmm without compression?

Hi Bob

> I don't see anything that would lead you to believe that
> the "blur filter" is only used for rendering still pictures,
> but not video. That doesn't even make sense to me.


I agree that the quoted statement of Dean did not make it clear whether the
filter is applied for everyhting or just the stills. However the thread in
which this statement was made was specifically for still images. Furthermore
the stills are treated differently already by assuming that these are made
up of square pixels always, while a source video is assessed for non-square
pixels as well...

Nevertheless I have asked Dean directly and received confirmation that the
filter is specific for the stills. Here is his reply to my question:


> From: "Dean Rowe"
> Sent: Thursday, August 18, 2005 10:59 PM
> Subject: RE: DV AVI blurring filter
>

> It is specific to still images; we don't use it on video as that would be
> very bad :-)
> Cheers
> Dean.
>
> -----Original Message-----
>> From: Rehan
>> Sent: Thursday, August 18, 2005 1:48 PM
>> To: Dean Rowe
>> Subject: DV AVI blurring filter
>>
>> Hi Dean
>>
>> I would like to clarify something about the NTSC-safe/blurring filter
>> that is applied for DV AVI output in Movie maker... Is it specific for
>> still images or it is applied for the video as well. For video it would
>> be detrimental for quality !!!
>>
>> See this thread in XP movie maker newsgroup:
>>
>> Subject: Saving a .wmm without compression?
>> news:eNqf0w2oFHA.3912@xxxxxxxxxxxxxxxxxxxx
>>
>>
>> Rehan
>> MS MVP -- Digital Media


--
Rehan
MS MVP -- Digital Media
www.rehanfx.org - get transitions and effects for Windows Movie Maker



"Bob [MVP]" <bob@xxxxxxxxxx> wrote in message
news:OpbFSGApFHA.3656@xxxxxxxxxxxxxxxxxxxxxxx
> Rehan,
>
>> Hi Bob, please note that this flaw affects only still pictures. For Video
>> that is captured in DV AVI, keeping it in the same format after editing
>> would still be best solution for quality.
>>
>
> This is what Dean wrote:
>
> *************************************************************
> When we save to DV-AVI we're assuming that you're ultimately
> targeting playback on a regular television as opposed to a
> computer monitor. Consequently when we're saving to DV-AVI we
> actually put a filter in the graph that ensures all colors
> are NTSC safe and it also slightly blurs the image. This is
> deliberate so that the image doesn't flicker so much on a
> regular TV. Of course this makes it look worse when you're
> looking at the result on a computer display, which is
> typically of a higher quality than a TV.
> **************************************************************
>
> "... it also slightly blurs the image."
>
> I don't see anything that would lead you to believe that
> the "blur filter" is only used for rendering still pictures,
> but not video. That doesn't even make sense to me.
>
> That is totally unacceptable IMHO when rendering to DV-AVI.
> I have always observed that the quality of the DV-AVI that MM
> creates is of (slightly) lower quality than the DV-AVI that
> was rendered by my miniDV camcorder. But I never understood
> why. Thanks to Dean's explanation, now I understand.
>
> If you have other information that leads you to conclude
> that a different filter graph is used based on the input
> media, please provide it. Otherwise, I'll stand by my
> original comments. Thanks.
>
> --
> -Bob
> _______________________________
> Microsoft MVP
> Windows XP Media Center Edition
> http://www.microsoft.com/ehome
>
>




.

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