The slope encodes the drift between the device clock and the computer
clock. Its real value is expected very close to 1.
To estimate it, just assume it is exactly 1.
Since the clock is used to estimate very close points in the future, the
error caused by clock drift is totally negligible, and in practice it is
way lower than the slope estimation error.
Therefore, only estimate the offset.
To minimize latency (at the cost of jitter), scrcpy always displays a
frame as soon as it available, without waiting.
However, when recording (--record), it still writes the captured
timestamps to the output file, so that the recorded file can be played
correctly without jitter.
Some real-time use cases might benefit from adding a small latency to
compensate for jitter too. For example, few tens of seconds of latency
for live-streaming are not important, but jitter is noticeable.
Therefore, implement a buffering mechanism (disabled by default) to add
a configurable latency delay.
PR #2417 <https://github.com/Genymobile/scrcpy/issues/2417>
