[FFmpeg-user] sntsc

[Mark Filipak]

On 12/26/23 09:30, Devin Heitmueller wrote:
> On Mon, Dec 25, 2023 at 4:04 AM Mark Filipak <markfilipak.imdb at gmail.com>
> wrote:
> 
>> On 12/22/23 16:09, Devin Heitmueller wrote:
>>> On Fri, Dec 22, 2023 at 3:57 PM Mark Filipak <markfilipak.imdb at gmail.com>
>> wrote:
>>>> On 12/22/23 15:14, Devin Heitmueller wrote:
>>>>> On Fri, Dec 22, 2023 at 2:38 PM Mark Filipak <
>> markfilipak.imdb at gmail.com> wrote:
>>>>>> This page: https://ffmpeg.org/ffmpeg-utils.html
>>>>>> 'says' this:
>>>>>>
>>>>>> "The following abbreviations are recognized:
>>>>>> "‘sntsc’
>>>>>> "    640x480"
>>>>>>
>>>>>> What is it? I'm not aware that any such thing exists.
>>>>>
>>>>> It's NTSC with square pixels...
>>>>
>>>> How do you go from 720x480 to 640x480 without throwing away 80 pixels
>> per line?
>>>> Normally, 720x480 decodes to 720x540.
>> -snip-
>>>
>>> Even worse, you can have 720x480 video with a display aspect ratio of
>>> 16:9 (i.e. standard definition widescreen).  In this case the pixel
>>> aspect ratio is going to be 40:33.
>>
>> Huh? "720x480 video with a display aspect ratio of 16:9" is what's on most
>> 'NTSC' DVDs. The PAR is
>> 32/27.

Oops. Sorry. SAR for 16:9 DVD is 32/27. PAR is 3/2.

You brought up 40/33. That's a PAR? A PAR for what?

And my original question: What is "sntsc"?

‘ntsc’   720x480
‘pal’    720x576
‘sntsc’  640x480
‘spal’   768x576

What ffmpeg is calling 'ntsc' & 'pal' are from film scanners targeting pseudo-NTSC DVDs and 
pseudo-PAL DVDs.

What ffmpeg is calling 'sntsc' & 'spal' don't have any relationship to NTSC and PAL, neither film 
nor broadcast, or to DVDs.

Why ffmpeg has put the letters 'ntsc' and 'pal' into 640x480 and 768x576 is a total mystery to me 
and continues the confusion many people have.

I'm sorry I brought it up. It was the marketing people who labeled DVDs as 'NTSC' or 'PAL'. FFmpeg 
is just propagating that myth. I simply ran across 'sntsc' and asked myself, "What is that?"