Optional. Maximum number of recognition hypotheses to be
returned. Specifically, the maximum number of
SpeechRecognitionAlternative messages within each
SpeechTranscription. The server may return fewer than
max_alternatives. Valid values are 0-30. A value
of 0 or 1 will return a maximum of one. If omitted,
will return a maximum of one.
Optional. A means to provide context to assist the speech
recognition.
Optional. For file formats, such as MXF or MKV, supporting
multiple audio tracks, specify up to two tracks. Default:
track 0.
Optional. If set, specifies the estimated number of speakers
in the conversation. If not set, defaults to '2'. Ignored
unless enable_speaker_diarization is set to true.
