On 4/23/2018 8:58 AM, Ronald S. Bultje wrote: > Hi, > > On Mon, Apr 23, 2018 at 2:10 AM, Karthick J <kjeya...@akamai.com> wrote: > >> - int level = par->level == FF_LEVEL_UNKNOWN ? 0 : par->level; >> + int level = par->level == FF_LEVEL_UNKNOWN ? >> + get_vp9_level(par, frame_rate) : par->level; > > > > After this change, how will I create a file without a level? > > This patch blurs the line between "unknown", "unspecified", "non-existent" > and "autodetect". Linguistically, each of these mean something > fundamentally different. I think it's acceptable to not have too many ways > of specifying something which in practice comes down to "nope", but you're > removing the "nope" altogether, which isn't quite right either.
The spec (VP9 in mp4) doesn't allow 0 nor defines an "unknown" value to be muxed into the vpcc atom. Technically speaking, we have been creating invalid files all this time by using 0 when the profile is unknown. See https://www.webmproject.org/vp9/mp4/ I don't think anything really looks at this field, beyond maybe just making sure it's a valid value if the parser is super pedantic, as it's not needed to actually start decoding. So an approximation is probably better than an out of range value like 0. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
