Executive Summary: A common problem with footage created using iPhones, screencam tools, Wirecast, and Skype is a loss of A/V sync when importing the video into Premiere Pro. This video tutorial presents a simple fix using Handbrake. You can read a tutorial on the Streaming Media Producer Website here.
Overview and discussion: Many sources of video, like mobile phones, screencam programs, live streaming software mixers (like Wirecast) and videoconferencing programs (like Skype) record video using a variable frame rate (VFR). When this video is played back in programs like VLC Player and QuickTime, the VFR doesn’t cause a problem. However, if you import the footage into a non-linear editor like Premiere Pro, the video can lose audio sync.
One quick and inexpensive fix is to use freeware encoding program Handbrake, which is available for Windows, Mac, and Ubuntu, to convert the footage from VFR to constant frame rate. To diagnose the problem, import the video into MediaInfo. If MediaInfo reports the footage as variable frame rate, as in the figure, converting to constant frame rate in Handbrake should fix the problem.
Here’s the tutorial.
Video tutorial: Two Free Video Analysis Tools; MediaInfo and Bitrate Viewer, Streaming Learning Center
Video tutorial, How to Encode with Handbrake, Jan Ozer, YouTube
About the Streaming Learning Center: The Streaming Learning Center is a premiere resource for companies seeking advice or training on cloud or on-premise encoder selection, preset creation, video quality optimization, adaptive bitrate distribution, and associated topics. Please contact Jan Ozer at firstname.lastname@example.org for more information about these services.