Anticipated questions¶

Here are the answers to the most asked/anticipated questions.

Why does the actual time differ from the target time?¶

The target time is the moment you requested, while the actual time is snapped to the nearest matching segment boundary, start or end. The difference between the two can be up to one full segment in length, with the segment duration depending on the YoutTube streaming latency settings: 1 second (ultra-low latency), 2 seconds (low latency), or 5 seconds for normal latency.

Why is the output duration longer than requested?¶

Segments are merged as-is, without trimming the boundary segments to match the requested interval. As a result, both boundaries can extend beyond the requested interval (see Why does the actual time differ from the target time?). This means the excerpt can be up to two full segments longer than requested: 2 seconds (ultra-low latency), 4 seconds (low), or 10 seconds (normal).

Why is the output duration shorter than requested?¶

Streams may contain gaps due to instability. A decrease in the duration of an output excerpt (by seconds, minutes, or even hours) can result from: (a) the start and/or end point falling within a gap, in which case the nearest available segment is used instead, or (b) the excerpt containing one or more gaps internally.