[MEncoder-users] Trying to fully understand de-interlacing.

[Grozdan]

On Tue, Jun 29, 2010 at 6:48 AM, Peter <pscientist at inbox.com> wrote:
> Grozdan wrote:
>>
>> It's not a compression. Interlacing is a trick used to reduce
>> bandwidth in the old days as at that time, bandwidth was very limited.
>> So if you "split" the image in two (odd and even) and first send the
>> odd (or even) filed then the even (or odd) field, it will use less
>> bandwidth compared to sending the whole image at once
>
> You're taking me too literally! When I said "a form of" I meant that it
> achieved
> the same results: halving the bandwidth, while delivering data that had a
> perceived quality which is better than half. (Trust me, I know very well how
> it
> works, LOL!)

Yes, but there's still a distinction between the two, even though they
try to achieve a similar result (reducing bandwidth) but from a
different angle. Compression throws away data, interlacing doesn't, it
splits the image in odd and even lines, and shows the odd or even
field first ;)

>
>> No, pp=ci will just deinterlace at normal frame rate so you'll get a
>> progressive image running at 29.970fps
>
> Oh, that's no good then.
>
>> if you want to create 60p (with an fps of 59.940) you have to use a
>> bobber like yadif=1 (and at your option combine it with mcdeint)
>
> Right, thanks.
>
>> parity=0 is tff while 1 is bff
>>
>> qp is for motion vector fields and how "smooth" they are at expense of
>> individual vectors. Most people use a value of 10
>>
>> Whether you'll see a (big?) difference between using yadif only and
>> yadif combined with mcdeint is up for discussion and depends on person
>> and content. A lot of people don't bother with mcdeint, either because
>> it's too slow or they can't see the difference between yadif only and
>> yadif + mcdeint
>
> I think I want to use mcdeint. I will try various yadif/mcdeint suggestions
> from
> this list and google searches, to see what seems best.

Well, you make sure you have a powerful machine, then ;)

You're doing 1080i content, using x264 (which can be pretty slow) and
yadif+mcdeint (which is slow almost always). That'll slow things a lot

>
> --
> Peter
>
> ____________________________________________________________
> Send your photos by email in seconds...
> TRY FREE IM TOOLPACK at http://www.imtoolpack.com/default.aspx?rc=if3
> Works in all emails, instant messengers, blogs, forums and social networks.
> _______________________________________________
> MEncoder-users mailing list
> MEncoder-users at mplayerhq.hu
> https://lists.mplayerhq.hu/mailman/listinfo/mencoder-users
>