Audio and video capture timestamps drift apart
Posted: Fri Jan 20, 2017 10:51 pm
Hi,
I have a customer complaining of audio/video drift when capturing HD-SDI with a Duo 2 (but I suspect other customers experience it with other DeckLink cards). The drift happens when there is a discontinuity on the SDI link : probably a video frame goes missing, and there are extra audio samples. At first it is not noticeable, but if you have one discontinuity a day for several weeks, the audio is delayed by several seconds.
In that state, VideoFrame->GetStreamTime returns timestamp t, and in the same callback AudioFrame->GetPacketTime returns timestamp t + 4 seconds. Should I assume that within the same callback, VideoFrame and AudioFrame should have the same presentation timestamp?
Best regards,
I have a customer complaining of audio/video drift when capturing HD-SDI with a Duo 2 (but I suspect other customers experience it with other DeckLink cards). The drift happens when there is a discontinuity on the SDI link : probably a video frame goes missing, and there are extra audio samples. At first it is not noticeable, but if you have one discontinuity a day for several weeks, the audio is delayed by several seconds.
In that state, VideoFrame->GetStreamTime returns timestamp t, and in the same callback AudioFrame->GetPacketTime returns timestamp t + 4 seconds. Should I assume that within the same callback, VideoFrame and AudioFrame should have the same presentation timestamp?
Best regards,