# NominalVideoTimestampModeError

## exception nominal.exceptions.NominalVideoTimestampModeError(message="exactly one of 'start' or 'frame_timestamps' must be provided")

Bases: [`NominalError`](https://dev.nominal.io/python/ref/generated/nominal.exceptions.NominalError.md#nominal.exceptions.NominalError "nominal.exceptions.NominalError"), [`ValueError`](https://docs.python.org/3/builtins/exceptions.html#ValueError "(in Python v3.15)")

Neither or both of a video’s timestamp modes were provided; exactly one is required.

Also a [`ValueError`](https://docs.python.org/3/builtins/exceptions.html#ValueError "(in Python v3.15)"), which is what these call sites raised before this type existed, so
`except ValueError` keeps working.

The default message names the two modes every video surface offers. The one surface that accepts
a third, `_build_video_file_timestamp_manifest`, passes its own.

Initialize error.