My video has not been encoded. Can I still send them in for synchronization?
Short answer is no, your media will need to be converted to .mpg or .mp4 first.
You will need to convert your media to a format that is supported by your trial presentation software and operating system. Currently (2019) some trial presentation applications prefer constant bitrate MPEG-1 media. Some prefer mpeg-4 (mp4) media files. Synchron can synchronize to either format, and many others.
Note: The free Synchronizer player for MacOS Catalina (10.15)+ is limited to video formats Apple supports, which simply put is mpeg-4 (.mp4) files for video. (Apple Supported Formats)