The preview request in <CoverPreview>.
optional
channelId: number
Zero-based channel; the firmware rejects a negative value.
optional
streamType: "mainStream" | "subStream" | "mobileStream" | "externStream"
The stream the recording was made from.
optional
startTime: CoverPreviewTime
Start of the recording.
optional
endTime: CoverPreviewTime
End of the recording.
optional
frameList: number[]
Frame numbers to preview, as <frameNo> items; up to 40 are read.