[FFmpeg-devel] [RFC/PATCH 1/2] lavf: add a flag for experimental (de)muxers

[Lynne]

2 Jan 2022, 18:46 by anton at khirnov.net:

> ---
>  doc/APIchanges         | 3 +++
>  libavformat/avformat.h | 7 +++++++
>  libavformat/format.c   | 2 ++
>  libavformat/version.h  | 2 +-
>  4 files changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/doc/APIchanges b/doc/APIchanges
> index 670a59329e..29c235630e 100644
> --- a/doc/APIchanges
> +++ b/doc/APIchanges
> @@ -14,6 +14,9 @@ libavutil:     2021-04-27
>  
>  API changes, most recent first:
>  
> +2022-01-xx - xxxxxxxxxx - lavf 59.13.100 - avformat.h
> +  Add AVFMT_EXPERIMENTAL flag.
> +
>  2021-12-xx - xxxxxxxxxx - lavu 57.13.100 - hwcontext_videotoolbox.h
>  Add av_vt_pixbuf_set_attachments
>  
> diff --git a/libavformat/avformat.h b/libavformat/avformat.h
> index 70b36d7682..6ce367e854 100644
> --- a/libavformat/avformat.h
> +++ b/libavformat/avformat.h
> @@ -463,6 +463,13 @@ typedef struct AVProbeData {
>  /// Demuxer will use avio_open, no opened file should be provided by the caller.
>  #define AVFMT_NOFILE        0x0001
>  #define AVFMT_NEEDNUMBER    0x0002 /**< Needs '%d' in filename. */
> +/**
> + * The muxer/demuxer is experimental and should be used with caution.
> + *
> + * - demuxers: will not be selected automatically by probing, must be specified
> + *             explicitly.
> + */
> +#define AVFMT_EXPERIMENTAL  0x0004
>  #define AVFMT_SHOW_IDS      0x0008 /**< Show format stream IDs numbers. */
>  #define AVFMT_GLOBALHEADER  0x0040 /**< Format wants global header. */
>  #define AVFMT_NOTIMESTAMPS  0x0080 /**< Format does not need / have any timestamps. */
> diff --git a/libavformat/format.c b/libavformat/format.c
> index 387627009e..52b85c16a2 100644
> --- a/libavformat/format.c
> +++ b/libavformat/format.c
> @@ -158,6 +158,8 @@ const AVInputFormat *av_probe_input_format3(const AVProbeData *pd,
>  }
>  
>  while ((fmt1 = av_demuxer_iterate(&i))) {
> +        if (fmt1->flags & AVFMT_EXPERIMENTAL)
> +            continue;
>  if (!is_opened == !(fmt1->flags & AVFMT_NOFILE) && strcmp(fmt1->name, "image2"))
>  continue;
>  score = 0;
> diff --git a/libavformat/version.h b/libavformat/version.h
> index 917b9ffa5d..29dcce352b 100644
> --- a/libavformat/version.h
> +++ b/libavformat/version.h
> @@ -32,7 +32,7 @@
>  // Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
>  // Also please add any ticket numbers that you believe might be affected here
>  #define LIBAVFORMAT_VERSION_MAJOR  59
> -#define LIBAVFORMAT_VERSION_MINOR  12
> +#define LIBAVFORMAT_VERSION_MINOR  13
>  #define LIBAVFORMAT_VERSION_MICRO 100
>  
>  #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
>

You should add it in libavformat/options_table.h too.
Apart from that, it looks fine. Should we move muxers previously
behind strict_std_compliance > experimental like scd behind
this flag or would that be an API breakage?