Does RTMP still have the 4GB problem?

Vangelis forthnet northmedia1 at
Sun Jul 5 17:49:33 PDT 2015

On Mon Jul 6 00:11:22 BST 2015, C E Macfarlane wrote:

> Does RTMP still have the 4GB problem?

Hi - please read:

... do not be lazy and check all the links referenced!

> I've been encountering problems playing back
> some of the long Wimbledon programmes.
> The files play so far, and then hang.
> I suspect that this is the rtmpdump 4GB problem...
> (snip)
> my download speeds are very slow

Are you on Windows?
Were those huge FLV files downloaded in one go
or was it that due to your slow connection rtmpdump
timed out and had to resume (possibly a number of times)
during the download?
The last case may have resulted in a corrupt FLV file
and that in turn could've resulted in a corrupt MP4 file
after the lossless remux by FFmpeg...
What media player did you use for playback
and at which point during the file's duration the hang occurs?
"flashhd" files have an average file size of ca. 0.9-1.0GiB/hour
(avg BR=2400kbps). What is the file size reported by
your File Manager (Windows Explorer?) and what is
the overall duration reported by your software player?
It may be wise to include the "--check-duration" switch in
your commands (=> Print message showing recorded duration,
expected duration and difference between them), although
this is useful when large differences are reported (i.e.
truncated downloads).
Can you live with the flashvhigh files (Res=832x468,
BR~1500kbps)? - their size is ~ 62% the size of their
flashhd counterparts...

> I am going to have to split the downloads
> using --stop and --start parameters.

If you plan to still use the flashhd tvmodes, this may
bring more ploblems than it solves:

Please try the newly implemented (in GiP 2.94) hlshd modes
(--tvmode=hlshd) - these use ffmpeg to record via HTTP, so
no RTMP protocol used (no 4GB limit applies to HTTP); however,
with your slow connection, you might still encounter problems with time-outs
(and missed HLS fragments) if latency is introduced during download...


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