But, do not record first packet time on an out-of-order packet.
It so happens that packets get out-of-order a lot more across relay.
And it turns out with some H.264 stream, the first few packets of a key
frame are very small (may be SPS/PPS, haven't checked), they get
out-of-oder quite a lot, so much so a down track never starts even it
has 20 - 25 key frames have passed through.
Raja Subramanian
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