[FFmpeg-user] What is 'yuv420p(tv, smpte170m, progressive)'?

[Mark Filipak]

On 05/19/2020 02:18 AM, Carl Eugen Hoyos wrote:
>> Am 19.05.2020 um 06:18 schrieb Mark Filipak <markfilipak.windows+ffmpeg at gmail.com>:
>>
>> relying on 'progressive' versus 'smpte170m'
> 
> I don’t think this distinction makes any sense.
> 
> Carl Eugen

Why do you say that, Carl Eugen?

If ffmpeg defines "progressive" as a video that contains picture-frames or soft telecine, then I 
want to simply transcode.

If ffmpeg uses "smpte170m" with "progressive" to denote hard telecine, then I want to detelecine first.

If ffmpeg uses "smpte170m" without "progressive" to denote odd/even scan fields separated by 
1/(field_rate) seconds (e.g. telecast video), then I want to either, 1, deinterlace, or 2, bob & 
frame double before transcoding.

If all that is correct, and if I can use ffprobe to determine those cases, then I can automate the 
transcodes via a script that processes individual source files or whole discs.

I realize there will be cases that require further probing (e.g. mixed sources such as "Making of" 
documentaries) or that require special processing (e.g. totally screwed up 'PTS's and/or audio sync 
problems), but those cases will be rare and will be evident when played back. I also realize that 
fixing up audio & subtitle streams (e.g. naming and setting defaults) will require something like 
MKVToolNix (or mkvmerge), but if I can bulk transcode several discs simultaneously, overnight, then 
the bulk of the job can be done while I sleep and I can do the fixups in the morning -- remuxing is 
fast.

I also realize that some videos use branching and that I have to look at 'mpls' & 'IFO' files 
because ffmpeg doesn't support those (or does it?), but I'll know about branching in advance and 
transcode them manually via HandBrake.

I value your input, but I need to understand it to make use of it. I hope that I've added enough 
distinction that it now makes sense. And I hope you and others will post back.

Thanks, and Regards - Mark.