[FFmpeg-devel] [PATCH] Clarifying the use of the scale filter interlace option
michaelni at gmx.at
Thu Mar 29 21:33:48 CEST 2012
On Thu, Mar 29, 2012 at 08:49:38AM +0100, Tim Nicholson wrote:
> On 27/03/12 18:50, Michael Niedermayer wrote:
> > On Tue, Mar 27, 2012 at 12:09:54PM +0100, Tim Nicholson wrote:
> >> On 27/03/12 07:47, Tim Nicholson wrote:
> >>> On 26/03/12 23:55, Michael Niedermayer wrote:
> >>>> On Mon, Mar 26, 2012 at 05:37:47PM +0100, Tim Nicholson wrote:
> >>>>> Based upon some recent queries on ffmpeg-user, and my own experience, a little
> >>>>> clarification of the documentation should help users in this area.
> > applied
> Whilst investigating this it occurred to me that this filter behaves
> differently by default to other filters and options.
> Commonly values of 1|0|-1 are used, with -1 meaning "auto" in whatever
> way that applies to the relevant filter/option, with the other values
> forcing a particular behaviour between a choice of 2. -1 is also
> commonly the default value.
> For example the following all use -1 as the default if not specified:-
> rawvideo top
> -mixing_level number
> -channel_coupling boolean
> -cpl_start_band number
> amovie|movie stream_index
> cellauto|life random_seed
> scale however only has 1|-1 with 0 having no defined meaning, although
> the logic dictates that since it is neither of the others it is an
> invalid choice and therefore ignored.
0 should mean progressive
> Also unlike other cases -1 (auto) is not the default.
this could be changed if it works better overall
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
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On any real computer, always possible as a real computer has a finite number
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