[FFmpeg-user] Video filtering for chroma dot crawl and rainbow effect

[Andy Furniss]

Andy Furniss wrote:
> Carl Eugen Hoyos wrote:
>> Christian Johannesen <chrisjohannesen <at> gmail.com> writes:
>>
>>> ffmpeg.exe  -r 30000/1001 -i D:\media\test_720x486i_dotcrawl.mov
>>
>> Please remove the input option -r unless you know exactly what you
>> are doing.
>>
>>> -filter_complex [0:0]crop=704:480:8:6,pullup
>
> Input on ticket is 4:2:0 and you can't crop vertically interlaced
> 4:2:0 by 6 without messing up the chroma. AFAIK you need to crop 4
> lines at a time.
>
> Maybe you could crop 6 if you converted (interlace aware) to 4:2:2
> crop and then interlace aware back to 4:2:0 (untested!).

Hmm, after looking at the trac sample I think the chroma has already
been scaled progressive = broken sample.

I may be wrong! only looked quickly.