[Ffmpeg-devel] [PATCH] AVOption defaults sync

[Panagiotis Issaris]

Hi,

Op donderdag 14 september 2006 15:11, schreef Baptiste Coudurier:
>[...]
> >>>>> The attached patch synchronizes the defaults specified in the AVOptions[] array 
> >>>>> to the defaults specified in the ffmpeg.c global static variabels. I took the
> >>>>> ones specified in ffmpeg.c as the new ones for AVOptions, as this preserves the 
> >>>>> current behavior. Regression tests pass.
> >>>> looks ok though i think that we should eventually change the default of 
> >>>> 12frame gop and 200kbit its probably not what most users would want
> >>> Does the "eventually" imply that I can commit the patch as is, and
> >>> that the defaults can be modified in a follow-up patch?
> >>>
> >>> If so, would 800kbit and 15 frame GOP be more in line with what users
> >>> want? Or should I post to ffmpeg-users and see what is being most
> >>> commonly used? :)
> >>>
> >> 12 is actually much used in MPEG-2 PAL since it's around 25/2 s, 15 is 
> >> more used in NTSC (30/2), DVD specs requires the gop not to be > 18, 
> >> MPEG-4 should use a much larger gop size though.
> > Well, the MPEG-4 codec is used by default, so I would assume it would
> > be most interesting to give it a "good" value for MPEG-4 encoding, and
> > ignore f.e. the DVD specs. If one wants DVD compliance, one will most
> > likely use the -target (pal|ntsc)-dvd anyway. Remains to be seen what
> > a "good" GOP size for MPEG-4 would be... :)
> > 
> 
> It depends on the output format. 'vob', 'mpg' uses mpeg2/mpeg1 respectively.
Hmm. Yes, you are right. But I think most generic containers default to MPEG-4,
well that was my impression at least.

With friendly regards,
Takis