Use host monotonic clock for timestamp#2802
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Previously, outgoing buffer timestamps in emulated_camera_mplane and emulated_camera_splane were calculated directly from the frame sequence index: tv_sec = (sequence + 1) / 1000 tv_usec = (sequence + 1) % 1000 This formula caused severe clock drift due to two issues: 1. Incorrect Time Scaling: sequence increments by 1 per frame. Dividing by 1000 caused tv_sec to advance by 1 second only after 1,000 frames (~33.3 seconds of real wall-clock time at 30 FPS). 2. Microsecond Miscalculation: In timeval, tv_usec is measured in microseconds (10^-6 s). Doing % 1000 without scaling caused the timestamp to advance by only 1 microsecond per frame. This change replaces the sequence-based calculation with the host's actual monotonic clock, avoiding timestamp drift and buffer rejections in the guest. Bug: b/474406105
ser-io
approved these changes
Jul 1, 2026
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Previously, outgoing buffer timestamps in emulated_camera_mplane and emulated_camera_splane were calculated directly from the frame sequence index:
tv_sec = (sequence + 1) / 1000
tv_usec = (sequence + 1) % 1000
This formula caused severe clock drift due to two issues:
This change replaces the sequence-based calculation with the host's actual monotonic clock, avoiding timestamp drift and buffer rejections in the guest.
Bug: b/474406105