[FFmpeg-devel] [PATCH 2/2] v4l2: allow to convert monotonic timestamps.
lucabe72 at email.it
Mon Mar 26 14:20:10 CEST 2012
On 03/21/2012 09:32 PM, Michael Niedermayer wrote:
> On Wed, Mar 21, 2012 at 07:52:24PM +0100, Nicolas George wrote:
>> L'octidi 18 ventôse, an CCXX, Nicolas George a écrit :
>>> Signed-off-by: Nicolas George<nicolas.george at normalesup.org>
>>> configure | 2 +
>>> doc/indevs.texi | 7 +++++
>>> libavdevice/Makefile | 2 +-
>>> libavdevice/v4l2.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>> 4 files changed, 82 insertions(+), 1 deletions(-)
> luca, do you have time to review the patch ?
I finally found the time to look at this patch... I found it on the mailing list
(please correct me if I looked at the wrong version of the patch).
I think the concept (allowing to convert from monotonic timestamps to
gettimeofday() times) is very good; I just have some questions on the
It seems to me that detect_timestamp() is invoked only when ts_mode == V4L_TS_ABS,
(use absolute timestamps) and it will either set ts_mode = V4L_TS_DEFAULT or fail...
What is the exact meaning of V4L_TS_ABS? Based on the source code, I'd call it
V4L_TS_AUTODETECT (isn't this what it is really doing?).
And I'd also offer an option to always perform the conversion, without any kind
Regarding the timestamps filtering code, I think it is ok if tested.
Also, it seems to me that the patch is adding two options (-ts and -timestamps) to
do the same thing... Why?
Finally, maybe (but I am not sure about this) av_gettime_monotonic() can be moved
to libavformat/utils.c, where av_gettime() already is.
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