[FFmpeg-user] FFmpeg HLS Output Blank During Live Stream — Possible Causes?

[Dennis Mungai]

On Thu, 8 May 2025 at 22:41, Vedant Bhugul <patilsvedant19 at gmail.com> wrote:

> Hi FFmpeg team,
> During a certain period, the HLS output (i.e., .ts segments and .m3u8
> playlist) remained blank for every live stream attempted. However, the .flv
> output stream continued to function normally. For each affected session, we
> had to manually terminate the FFmpeg transcoding process—only then did the
> HLS output recover and begin functioning correctly. The issue resolved
> itself after this period and has not reoccurred since. It also remains
> unreproducible.
>
> Note: Unfortunately, I do not have the FFmpeg logs from the time of the
> incident.
>
> I have attached the code-snippets.txt file for your reference.
>
> I tried adding delays both in the transcoding server code and on the ingest
> server side to see if it would help reproduce the issue, but none of these
> attempts had any effect. The problem did not occur again and remains
> unreproducible.
>
> *I would appreciate any guidance or assistance in identifying the root
> cause of this issue* to ensure it does not recur in the future.
>
> Best Regards,
> Vedant
>

Add -pix_fmt yuv420p right after -c:v libx264 and retest.