[FFmpeg-user] sntsc

[Mark Filipak]

On 1/8/24 00:26, Andrew Randrianasulu wrote:
> пн, 8 янв. 2024 г., 05:14 Mark Filipak <markfilipak.imdb at gmail.com>:
>> What is it that you want to know?
>>
> 
> I think I like to try and see bigger picture behind acronyms.

What acronyms?

> At least this page explains how some 640*480 files  might be born (it
> should be 486, but some lines are cut).

Nonsense. If you're referring to DVD, there's no such thing as 640x480.
There's 720x480. It decodes to 720x540.

> https://lurkertech.com/lg/video-systems/#480i

Total Lines Per Frame	525. Nobody has those TVs anymore.

> This is all interesting and not really theoretical to me because at least
> one our user still have a lot of HDV and DV material and he hopes to get
> correct encoding results in those cases too!

Sorry, I can't help there. I don't know what HDV & DV are. Is your friend trying to make a standards 
compliant DVD or BD? No? Then the correct encoding results are whatever can do the capture or the 
remux or the transcoding.

I assume HDV & DV are analog, otherwise, why are you fussing about 704 & 525? If HDV & DV are 
digital, then 704 & 252 don't apply.

All that analog capture stuff is moot. Get everything you can and then use ffmpeg to crop to 
whatever the image is. As long as the capture hardware is running at 60/1.001 fields per second, the 
field-to-field images should be stable and you'll be fine. If the videos are hand held camcorder, 
then the images will not be stable, but there are stabilizers you can use. Just get the images, then 
worry about presentation.