The Wowza Streaming Engine Transcoder supports only live transcoding. If you are familiar with a program called FFmpeg your development team may be interested in the following article.
For a better streaming media experience you need to ensure that your keyframes are created every two seconds using the FFmpeg “-g” option and the “-x264opts no-scenecut” option on the command line. Together they will make the keyframe distance, or Group of Pictures (GOP), the exact number of frames you specify. For example if you have a 23.976fps file your GOP should be 48.
I hope that this information helps to answer your question.