14 Dec 2021, 09:32 by c...@passwd.hu: > > > On Tue, 14 Dec 2021, Lynne wrote: > >> 14 Dec 2021, 02:13 by c...@passwd.hu: >> >>> >>> >>> On Tue, 7 Dec 2021, James Almer wrote: >>> >>> I would like to attach some extendable, possibly per-channel metadata to >>> the channel layout. I'd rather put it into AVChannelLayout, so native >>> layouts could also have metadata. This must be dynamically allocated to >>> make it extendable and to not consume too many bytes. I can accept that it >>> will be slow. But I don't see it unmanagable, because AVChannelLayout >>> already have functions for allocation/free/copy. I also think that most of >>> the time it will not be used (e.g. if metadata is NULL, that can mean no >>> metadata for all the channels). >>> >>> If we can't decide what this should be, array of AVDictionaries, some >>> side-data like approach but in the channel layout, or a new dynamically >>> allocated AVChannelLayoutMetadata struct, then maybe just reserve a void* >>> in the end of the AVChannelLayout, and we can work it out later. >>> >> >> The idea to use opaque indices is IMO better. You can store any >> metadata you want into the frame->opaque(_buf) field, and it'll >> be completely copied of av_frame_ref(). >> If we go for an opaque pointer, I'd like for it to be copied (by >> value, not data) into any ref'd frames. I'd prefer an opaque >> field over an opaque metadata field. >> > > It's not just frames which have channel layouts, but AVCodecParameters, > AVStreams or AVFilterLinks. It is not the user defined metadata we have a > problem storing/getting, but framework (demuxer, filter) defined metadata. >
In that case, I think it's fine to have a dictionary metadata field in the per-channel struct, It'll increase the struct size slightly, but I think it's acceptable. I think this discussion would go a lot quicker if we could discuss this on IRC, would you and Nicolas mind joining and pinging me and elenril so we could settle the details? _______________________________________________ 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".
