[FFmpeg-user] DOWN CONVERSION ISSUE: From MXF (1080i AVC Intra) - MBAFF "interlacing" to DVCPRO

[Tim Nicholson]

On 26/03/12 11:34, Iban Garcia wrote:
> Umm... it does not work for me. The output.dv is still "progressive"
> (de-interlaced): both fields of output.dv file are equal. The interlacing
> has been lost...
> 

OK so something is not working as it should. I have had a look at some of my
H264 10bit interlaced material and that is also behaving as you describe. The
source is definitely interlaced, as can be seen from the interlace artifacts in
a resized ffplay window. But the output is a blend of the two fields.

I will try and get some more details and then raise a bug report.

> I have download and installed "ffmbc". I am doing some test now with it.
> But, by the moment, all of the tests has the same "de-interlaced" output...
> :-(((
> 
> 
> 2012/3/26 Tim Nicholson <nichot20 at yahoo.com>
> 
>> On 25/03/12 15:43, Iban Garcia wrote:
>>> Hi,
>>>
>>> I have taken from git the last version of ffmpeg. And I have made next
>>> test. The output.dv fields are not interlaced. The interlaced information
>>> has been lost in the process.
>>>
>>> # ffmpeg -y -threads 8 -i input.mxf -s 720x576 -pix_fmt yuv411p -aspect
>>> 16:9 -an -r 25 -vf "setfield=1, fieldorder=bff" output.dv
>>
>>> [..]
>>
>>> sws_param:
>>> [fieldorder @ 0x646e80] output field order: bff
>>> [scale @ 0x6283a0] w:1920 h:1080 fmt:yuv422p10le sar:1/1 -> w:720 h:576
>>> fmt:yuv411p sar:64/45 flags:0x4
>>>
>>
>> As your source is HD and you wish to output SD, you should really scale the
>> material properly using the "scale" filter with interlacing turned on.
>>
>> Something like:-
>>
>> ffmpeg -y -threads 8 -i input.mxf \
>> -vf "setfield=1, scale=720:576:1, fieldorder=bff" \
>> -pix_fmt yuv411p -aspect 16:9 -an -r 25 output.dv
>>
>> --
>> Tim
>> _______________________________________________

-- 
Tim