How to match ffmpeg output in logs to a path?

[moenodedev]

Question

We're seeing thousands of ffmpeg messages like this while watching the logs.

[flv @ 0x7f1652fa3600] Non-monotonic DTS in output stream 0:1; previous: 33193252, current: 33193234; changing to 33193252. This may result in incorrect timestamps in the output file.

How do we determine which path the ffmpeg output belongs to?

[aler9]

duplicate of #2034