[FFmpeg-devel] [PATCH 2/3] avformat/mxfdec: support subsecond precision of decoded timestamps

[Tomas Härdin]

sön 2018-12-23 klockan 01:12 +0100 skrev Marton Balint:
> > Signed-off-by: Marton Balint <cus at passwd.hu>
> ---
>  libavformat/mxfdec.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
> index d78f8ad2e4..0553adcb06 100644
> --- a/libavformat/mxfdec.c
> +++ b/libavformat/mxfdec.c
> @@ -2556,12 +2556,14 @@ fail_and_free:
>  static int64_t mxf_timestamp_to_int64(uint64_t timestamp)
>  {
>      struct tm time = { 0 };
> +    int msecs;
>      time.tm_year = (timestamp >> 48) - 1900;
>      time.tm_mon  = (timestamp >> 40 & 0xFF) - 1;
>      time.tm_mday = (timestamp >> 32 & 0xFF);
>      time.tm_hour = (timestamp >> 24 & 0xFF);
>      time.tm_min  = (timestamp >> 16 & 0xFF);
>      time.tm_sec  = (timestamp >> 8  & 0xFF);
> +    msecs        = (timestamp & 0xFF) * 4;
>  
>      /* Clip values for legacy reasons. Maybe we should return error instead? */
>      time.tm_mon  = av_clip(time.tm_mon,  0, 11);
> @@ -2569,8 +2571,9 @@ static int64_t mxf_timestamp_to_int64(uint64_t timestamp)
>      time.tm_hour = av_clip(time.tm_hour, 0, 23);
>      time.tm_min  = av_clip(time.tm_min,  0, 59);
>      time.tm_sec  = av_clip(time.tm_sec,  0, 59);
> +    msecs        = av_clip(msecs, 0, 999);
>  
> -    return (int64_t)av_timegm(&time) * 1000000;
> +    return (int64_t)av_timegm(&time) * 1000000 + msecs * 1000;

Looks OK

I kinda wonder how this and the muxer code could have ignored the
milliseconds. Did the old creation time metadata use seconds only?

/Tomas