[FFmpeg-devel] [PATCH 2/2] fftools/ffmpeg: log skipped initial non-keyframes

[Moritz Barsnick]

On Thu, Jun 06, 2019 at 22:31:45 +0200, Stephan Hilb wrote:
> If `AV_PKT_FLAG_KEY` stays unset on `pkt->flags`, the output stream
> stays empty with little information about what is going on.
> This change makes it easier to debug the situation for the user who
> could then choose to use the `-copyinkf` option.
[...]
> -        !ost->copy_initial_nonkeyframes)
> +        !ost->copy_initial_nonkeyframes) {
> +        av_log(NULL, AV_LOG_DEBUG, "skipping initial non-keyframe\n");
>          return;

Incorrect indentation.

More seriously: I welcome this message. There was a question on
ffmpeg-user[1] recently where a user provided a file without any
keyframes at all, which could be played by ffplay, but not copy-coded
by ffmpeg.

I suggest this message should be at INFO level, but appear only once.
Unfortunately, the file said user provided is no longer available (and
I have deleted my copy).

I believe ffprobe also suffers from such files and never displays
anyhing with -show_frames. In fact, does ffprobe perhaps always begin
from, or at least wait for, the first keyframe?

Cheers,
Moritz

[1] http://ffmpeg.org/pipermail/ffmpeg-user/2019-June/044526.html