[FFmpeg-user] converting 1080p50 to PAL interlaced dv format

[Boštjan Strojan]

i assumed your hd input is 1080i50, will check the sample now.

b.

On Wed, Jan 25, 2012 at 1:42 AM, Konrad Karl <kk_konrad at gmx.at> wrote:
> Hi,
>
> On Tue, Jan 24, 2012 at 08:01:51PM +0100, Bo??tjan Strojan wrote:
>> I don't have a command line ready, but the filter order might be:
>>
>> 1. crop width
>> 2. resize width to final size
>> 3. bob deinterlace (maybe yadif) to get double frame rate
>
> this I don't understand: why would I need double frame rate?
>
> 1080p50 is already 50 full frames per second and the output should
> be interlaced to have 25 full frames per second using two fields,
> lower field first.
>
> from http://www.dvmp.co.uk/digital-video.htm (DV & DVCAM)
>
> "Consequently in both systems field 1 is the "lower" field .
> Field 1 dominance effectively means that the field order of DV material
> is "lower field first" for both PAL and NTSC, which is nice! "
>
> So after steps 1 and 2 above the video already has correct size with
> 50 full frames per second and now interlacing should produce two frames
> of 1/50 second duration each (assuming  non-interlaced lines are numbered 1..576):
>
> lower  frame: taking lines 2,4,6....576  from the first  50p frame
> higher frame: lines 1,3,4....575         from the second 50p frame
> and so on.
>
> I think the DV pixels are not quadratic (dont know for sure yet) then this should
> be taken into account during step 1 and 2.
>
> Does this make sense so far?
>
>> 4. resize height to final/2
>> 5. reinterlace (maybe using tinterlace)
>
> Thanks for mentioning tinterlace, did not know about it.
>
>> or maybe just
>>
>> 1. crop width
>> 2. crop height (keeping in mind line scan order)
>> 3. resize (use interl=1 with scale command)
>>
>> can you upload a short sample (the one that has a lot of motion)?
>
> I have put a very short example 1080p50 video here:
>
> http://140.78.117.254:88/avchd/out.mts.bin
> (~ 3.5MB)
>
> it has been extracted from a longer clip:
>
> ffmpeg -i 00023.MTS -ss 00:00:03.5 -t 00:00:01.500 -acodec copy -vcodec copy -f mpegts out.mts
>
> since I was unable to get a short enough clip by using the record button :-)
>
> will experiment using your suggestions tomorrow which forces me to read
> the man page a couple of times I think. A command line example about
> using "resize (use interl=1 with scale command)" and/or "(maybe using
> tinterlace)" will let me reach my goal a lot faster, I guess.
>
> Many thanks,
>
> Konrad
>
>> b.
>>
>> On Tue, Jan 24, 2012 at 6:47 PM, Konrad Karl <kk_konrad at gmx.at> wrote:
>> > Dear all,
>> >
>> > is this possible with current ffmpeg (Fedora 16, but I can compile myself)?
>> > Google did not help so far, "interlaced" triggers lots of search results
>> > about de-interlacing....
>> _______________________________________________
>> ffmpeg-user mailing list
>> ffmpeg-user at ffmpeg.org
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user