[FFmpeg-devel] [PATCH 1/6 v2] lavu: add av_gettime_relative()

Michael Niedermayer michaelni at gmx.at
Sat May 17 15:38:17 CEST 2014

On Mon, May 12, 2014 at 04:26:37PM -0400, Olivier Langlois wrote:
> These functions are using the POSIX clock_gettime() function with the
> CLOCK_MONOTONIC clock id. If these are not present on the targeted
> platform, the new functions will fallback on using the original realtime functions
> av_gettime() and av_usleep().
> Monotonic support can be added on other platforms with their
> equivalent native system API eventually if possible.
> Whenever time is requested to measure relative time, the monotonic clock,
> when available, is superior to the system realtime clock because it is
> not affected by discontinuous jumps in the system time
> In a future step, offering the flexibility to let the user choose between
> rt and monotonic clock for avdevices packets will be investigated.
> It is very easy to experience the issues that this patch attempt to address
> by rewinding back in the past the system time while ffmpeg is running.
> this is breaking the ffmpeg report printing (ffmepg.c:print_report()) and
> the the rate emulator functionality (-re) without the patch.
> Signed-off-by: Olivier Langlois <olivier at trillion01.com>
> ---
>  libavutil/time.c | 20 ++++++++++++++++++++
>  libavutil/time.h | 15 +++++++++++++++
>  2 files changed, 35 insertions(+)

patch applied


Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

He who knows, does not speak. He who speaks, does not know. -- Lao Tsu
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20140517/8a4d826a/attachment.asc>

More information about the ffmpeg-devel mailing list