[FFmpeg-devel] [PATCH v5 2/3] avdevice/lavfi: support the dumpgraph with options

[Marton Balint]

On Sun, 24 May 2020, lance.lmwang at gmail.com wrote:

> From: Limin Wang <lance.lmwang at gmail.com>
>
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
> doc/indevs.texi     | 15 +++++++++++++--
> libavdevice/lavfi.c |  2 +-
> 2 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/doc/indevs.texi b/doc/indevs.texi
> index 6f5afaf..7ec7062 100644
> --- a/doc/indevs.texi
> +++ b/doc/indevs.texi
> @@ -973,8 +973,13 @@ Set the filename of the filtergraph to be read and sent to the other
> filters. Syntax of the filtergraph is the same as the one specified by
> the option @var{graph}.
> 
> - at item dumpgraph
> -Dump graph to stderr.
> + at item dumpgraph @var{options}
> +Dump graph to stderr with more options
> +
> +options is a ':'-separated list of @var{key=value} pairs.
> +
> +Set the graph with graphviz DOT format by @var{fmt=dot|DOT},
> +set the filename of filtergraph to output by @var{filename=path}.
> 
> @end table
> 
> @@ -988,6 +993,12 @@ ffplay -f lavfi -graph "color=c=pink [out0]" dummy
> @end example
> 
> @item
> +dump the filter graph with graphviz DOT output format to ./test.tmp
> + at example
> +ffplay -dumpgraph fmt=dot:filename=./test.tmp -f lavfi color=c=pink
> + at end example
> +
> + at item
> As the previous example, but use filename for specifying the graph
> description, and omit the "out0" label:
> @example
> diff --git a/libavdevice/lavfi.c b/libavdevice/lavfi.c
> index c949ff7..fa75fde 100644
> --- a/libavdevice/lavfi.c
> +++ b/libavdevice/lavfi.c
> @@ -493,7 +493,7 @@ static int lavfi_read_packet(AVFormatContext *avctx, AVPacket *pkt)
> static const AVOption options[] = {
>     { "graph",     "set libavfilter graph", OFFSET(graph_str),  AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
>     { "graph_file","set libavfilter graph filename", OFFSET(graph_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC},
> -    { "dumpgraph", "dump graph to stderr",  OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
> +    { "dumpgraph", "dump graph to stderr with more options",  OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },

There are examples in the docs which use -dumpgraph 1, but if -dumpgraph 
is parsed as a dictionary, then that will not work anymore.

Maybe it is cleaner to specify the options in a separate option, 
e.g. -dumpgraph_opts, and change the type of -dumpgraph to BOOL? After all 
you should be able to dumpgraph with no options specified, right?

Regards,
Marton