What counts as an Analytics impression?

An Analytics billing impression is defined in the same way as a “Play” in the Analytics dashboard.
We count an impression when a viewer saw at least one frame of a video. In technical terms, we count an impression once a session had a Video Startup Time:

Example A

As pictured in the impression log below, the session had a Video Startuptime of 0.39 seconds and consequently will be counted as an Analytics impression.

The Video Startuptime is visible in the row showing the 'startup' state. All other rows show events within the session which do not count as an impression because they do not have a Video Startuptime.

Example B

As pictured in the impression log below, the session had an error before playback could commence. Consequently, the session also does not display a video startup time and consequently will NOT be counted as an Analytics impression.