[mythtv-users] HDTV on Myth -- is it a "myth?"

[Doug Larrick]

Joe Barnhart wrote:
> --- Doug Larrick <doug at ties.org> wrote:
> 
> 
>>Joe Barnhart wrote:
>>
>>>Hmm.. Doesn't something seem fundamentally wrong
>>
>>about
>>
>>>this?  Why should 1920x540 look the same as
>>
>>1920x1080?
>>
>>1080i at 30 Hz is identically the same as 540p at 60
>>Hz.  Suggest you do 
>>some reading.
> 
> 
> What is the same, Doug?  The horizontal scanning
> frequency of 33.75kHz?  I agree.  How about the image?
>  With 1080i you get two different frames of
> information, 30 times each second.  With 540p you get
> two identical frames 30 times each second.  Shouldn't
> they look different?  I think they should.

No.

1080i = 2 fields of 540 lines, at 30 Hz

540p = 1 frame of 540 lines, at 60 Hz.

Six of one, half a dozen of the other.  Almost literally.

-Doug
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