[FFmpeg-devel] hevc_probe won't recognize stream

[Hendrik Leppkes]

On Wed, Jan 14, 2015 at 6:04 PM, Ståle Kristoffersen <staalebk at ifi.uio.no>
wrote:

> I have a TS-file, which I unfortunately can't share, that contains only one
> PID, and that is a 4K HEVC-video stream at around 30Mbps.
> This file is from the middle of a broadcast and thus it do not start
> cleanly.
>
> ffmpeg is not able to detect that the file is HEVC, and falls back to AAC
> (with a score of 1), see [1].
> I have tried to increase -probesize, but that does not seem to make any
> difference.
>
> After digging around I found that for hevc_probe to detect a stream it must
> see at least the following NALs: "VPS", "SPS", "PPS" and "IRAP". My file
> does not have thos NALs in the first 2.5 MB of the file, and it seems the
> probe gives up after RAW_PACKET_BUFFER_SIZE (2500000) bytes.
>
> Increasing that and recompiling makes ffmpeg work fine.
>
> What is the correct approach for fixing this?
>

You can override this limit yourself with the format_probesize option, no
need to recompile.

- Hendrik