Encoding and processing are two terms associated with changing the format of a video. When you upload a video to SproutVideo, its format needs to be changed and standardized so that it can be played back on the web. This is represented by messaging on site that may say "Preparing for encoding..." or "Encoding..."
Larger video files will take longer to encode. Higher resolution (HD, etc) video files will also take longer to encode. Please be patient while your video encodes as it can take several hours for some videos to fully process and become playable on the web.