On Mon, 08 Apr 2024 22:18:33 +0200 Michael Niedermayer <mich...@niedermayer.cc> wrote: > On Fri, Apr 05, 2024 at 08:57:11PM +0200, Niklas Haas wrote: > > From: Niklas Haas <g...@haasn.dev> > > > > This replaces the myriad of existing lists in AVCodec by a unified API > > call, allowing us to (ultimately) trim down the sizeof(AVCodec) quite > > substantially, while also making this more trivially extensible. > > > > In addition to the already covered lists, add two new entries for color > > space and color range, mirroring the newly added negotiable fields in > > libavfilter. > > > > I decided to drop the explicit length field from the API proposed by > > Andreas Rheinhardt, because having it in place ended up complicating > > both the codec side and the client side implementations, while also > > being strictly less flexible (it's trivial to recover a length given > > a terminator, but requires allocation to add a terminator given > > a length). Using a terminator also presents less of a porting challenge > > for existing users of the current API. > > > > Once the deprecation period passes for the existing public fields, the > > rough plan is to move the commonly used fields (such as > > pix_fmt/sample_fmt) into FFCodec, possibly as a union of audio and video > > configuration types, and then implement the rarely used fields with > > custom callbacks. > > --- > > doc/APIchanges | 5 ++++ > > libavcodec/avcodec.c | 51 +++++++++++++++++++++++++++++++++++++ > > libavcodec/avcodec.h | 27 ++++++++++++++++++++ > > libavcodec/codec.h | 19 +++++++++++--- > > libavcodec/codec_internal.h | 21 +++++++++++++++ > > libavcodec/version.h | 4 +-- > > 6 files changed, 121 insertions(+), 6 deletions(-) > > This patchset seems to overlap a bit with AVOptionRanges > > I think ideally the user should at some point be able to query using some > API on a AVCodecContext/AVCodecParameters/AVFormatContex/AVStream > what for that specific instance are supported settings for each field > > The API here seems to use a enum, which can make sense but it differs from > how AVOption works which doesnt use enums to identify fields
I didn't know AVOptionRanges exists; indeed it can be seen as somewhat overlapping here. That said, there is a vital distinction here: AVOptionRanges represents *static* limits on what options can be set (e.g. via `av_opt_set_int`), whereas this API represents *dynamic* limits on what can be coded. In particular, the list of supported colorspaces etc. can *depend* on the value of other options. Currently, only strict_std_compliance, but I can easily see this list growing in the future (e.g. for different profiles, dolbyvision, ...). That aside, I personally find an API based on strings and doubles rather cumbersome to use, especially when downstream clients expect an enum list. > > > [...] > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > Never trust a computer, one day, it may think you are the virus. -- Compn > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
