This month we take a more detailed look at one of the more powerful features of Cozimo – the ability to review and annotate video. Cozimo’s system allows any number of remote team members to play and annotate a video from any standard web browser. Members can review videos on their own or you can have online meetings where the playback and annotation are fully synchronized between all participants. To optimize the real-time performance of the system, we recommend that video files posted for review and feedback not be larger than necessary for the type of feedback required (there is a 60 MB per file limit).

Formats and Encoding – Cozimo supports most popular video formats, including QuickTime (.mov), MPEG (.mpg, .mp4), AVI, Windows media (.wmv) and Flash video (.flv). When formats other than .flv are uploaded an .flv proxy is created for the purposes of playback and review. Because the encoding occurs on the fly at upload, there may be a delay between the time that the file uploads and the thumbnail of the file appears in the file tab indicating that it is available for review. This delay is usually a few minutes but it can sometimes take quite a bit longer if the file is large (or the encoding server very busy).

The encoding parameters have been set to preserve the resolution and quality of the original file as much as possible though with any encoding process there can be variations so it’s a good idea to check the result prior to distribution if this can be an issue. You can maintain complete control of the quality by uploading your own .flv files. This way you avoid the encoding delay as well.

Playback  and Annotation – During playback, video files are progressively downloaded to the browser (not streamed). You can start playing the video clip after 20% of the file has downloaded. File download progress is indicated as an orange line in the scrub bar:

Use the buttons or hotkeys to control the playback as shown below:

Click on the label above the controls to toggle between a timecode display or frame count:

Stop on any keyframe to make annotations on it as you would on any image. Frames that have annotations on them are indicated with a blue marker in the timeline. By default, Cozimo inserts a keyframe at every six frames during the encoding process. If you upload your own .flv files you can insert keyframes at any frequency you wish.

To synchronize the playback of the video between multiple collaborators, click on “Presenter Mode”. While in presenter mode you can play the video or scrub to any keyframe and all participants will be synchronized to the same frame. When you stop to annotate all participants can “whiteboard” on the same frame together. If a participant moves off the synchronized playback to view the video independently, the presenter can re-synchronize the participant by pausing and restarting the playback. Any collaborator can click on Presenter Mode at any time to take control of the playback.