[FFmpeg-devel] [PATCH] lavc/bsf: add a showinfo filter

[Alexander Strasser]

On 2024-01-29 19:42 +0100, Anton Khirnov wrote:
[...]
> --- a/doc/bitstream_filters.texi
> +++ b/doc/bitstream_filters.texi
> @@ -887,6 +887,10 @@ For example, to set PTS equal to DTS (not recommended if B-frames are involved):
>  ffmpeg -i INPUT -c:a copy -bsf:a setts=pts=DTS out.mkv
>  @end example
>
> + at section showinfo
> +Log basic packet information. Mainly useful for testing, debugging,
> +and development.
> +

Maybe it's a good idea to state something about the stability of
the output format. I assume it's to be treated like other logging
and is not expected to stay stable. Not sure how much it helps to
state it clearly, but it can't hurt IMHO.


[...]
> --- /dev/null
> +++ b/libavcodec/bsf/showinfo.c
[...]
> +static int showinfo_filter(AVBSFContext *ctx, AVPacket *pkt)
> +{
> +    ShowinfoContext *priv = ctx->priv_data;
> +
> +    while (1) {
> +        int ret;
> +
> +        ret = ff_bsf_get_packet_ref(ctx, pkt);
> +        if (ret < 0)
> +            return ret;
> +
> +        av_log(ctx, AV_LOG_INFO,
> +               "n:%7"PRIu64" "
> +               "size:%7d "
> +               "pts:%s pt:%s "
> +               "dts:%s dt:%s "
> +               "ds:%"PRId64" d:%s "
> +               "\n",
> +               priv->nb_packets, pkt->size,
> +               av_ts2str(pkt->pts), av_ts2timestr(pkt->pts, &ctx->time_base_in),
> +               av_ts2str(pkt->dts), av_ts2timestr(pkt->dts, &ctx->time_base_in),
> +               pkt->duration, av_ts2timestr(pkt->duration, &ctx->time_base_in));
> +
> +        priv->nb_packets++;
> +
> +        return 0;
> +    }
> +}

It's late here and I surely must be missing something. Anyway,
why do we use a while loop here?


Best regards,
  Alexander

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