[FFmpeg-user] field_sequence from H.262

[Mark Filipak]

On 24/05/2024 13.19, Andrew Randrianasulu wrote:
> пт, 24 мая 2024 г., 20:16 Mark Filipak <markfilipak.imdb at gmail.com>:
> 
>> This is from H.262.
>>    ___________________________________________________________________
>> |                                                                   |
>> | field_sequence – A 3-bit integer which defines the number of the  |
>> | field in the eight field sequence used in PAL systems or the four |
>> | field sequence used in NTSC systems as defined in the Table 6-15. |
>> |                                                                   |
>> | Table 6-15 – Definition of field_sequence                         |
>> | Field sequence  Frame  Field                                      |
>> |      000          1      1                                        |
>> |      001          1      2                                        |
>> |      010          2      3                                        |
>> |      011          2      4                                        |
>> |      100          3      5                                        |
>> |      101          3      6                                        |
>> |      110          4      7                                        |
>> |      111          4      8                                        |
>> |___________________________________________________________________|
>>
>> That is a quote of the complete section.
>>
>> Does anyone know what MPEG is trying to say?
>>
> 
> 
> 
> my guess: telecine pattern?

Nope. Hard telecine is covered by top_field_first and is indistinguishable from television unless 
you single step through the pictures looking for motion combing in every frame. Soft telecine is 
covered by top_field_first and repeat_first_field and is evident while single stepping and looking 
for motion combing patterns due to pull-down. This is something different, but I've never been able 
to figure out what it is.