[FFmpeg-devel] [PATCH] avfilter/f_metadata: allow direct flushing when printing to file

[Gyan]

On 07-01-2020 05:44 pm, Gyan Doshi wrote:
> Useful for monitoring sparse data in realtime
> ---
>   doc/filters.texi         | 3 +++
>   libavfilter/f_metadata.c | 6 ++++++
>   2 files changed, 9 insertions(+)
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index fc2d198077..e682ba62bb 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -22711,6 +22711,9 @@ plain filename any writable url can be specified. Filename ``-'' is a shorthand
>   for standard output. If @code{file} option is not set, output is written to the log
>   with AV_LOG_INFO loglevel.
>   
> + at item direct
> +Reduces buffering in print mode when output is written to a URL set using @var{file}.
> +
>   @end table
>   
>   @subsection Examples
> diff --git a/libavfilter/f_metadata.c b/libavfilter/f_metadata.c
> index 3bf4bb17f5..bf298e9d39 100644
> --- a/libavfilter/f_metadata.c
> +++ b/libavfilter/f_metadata.c
> @@ -88,6 +88,8 @@ typedef struct MetadataContext {
>       int (*compare)(struct MetadataContext *s,
>                      const char *value1, const char *value2);
>       void (*print)(AVFilterContext *ctx, const char *msg, ...) av_printf_format(2, 3);
> +
> +    int direct;    // reduces buffering when printing to user-supplied URL
>   } MetadataContext;
>   
>   #define OFFSET(x) offsetof(MetadataContext, x)
> @@ -111,6 +113,7 @@ static const AVOption filt_name##_options[] = { \
>       {   "ends_with",   NULL, 0, AV_OPT_TYPE_CONST, {.i64 = METADATAF_ENDS_WITH },   0, 0, FLAGS, "function" }, \
>       { "expr", "set expression for expr function", OFFSET(expr_str), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, FLAGS }, \
>       { "file", "set file where to print metadata information", OFFSET(file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS }, \
> +    { "direct", "reduce buffering when printing to user-set file or pipe", OFFSET(direct), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS }, \
>       { NULL } \
>   }
>   
> @@ -274,6 +277,9 @@ static av_cold int init(AVFilterContext *ctx)
>                      s->file_str, buf);
>               return ret;
>           }
> +
> +        if (s->direct)
> +            s->avio_context->direct = AVIO_FLAG_DIRECT;
>       }
>   
>       return 0;

Plan to push tonight.

Gyan