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

[Marton Balint]

On Tue, 25 Dec 2018, Tomas Härdin wrote:

> 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

Thanks, pushed this and the other patch.

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

Yes, it used to be in this format: "%Y-%m-%d %H:%M:%S".

Regards,
Marton