Merge "Camera: Handle deviation between frame duration and vsync intervals am:...

#define ATRACE_TAG ATRACE_TAG_CAMERA

//#define LOG_NDEBUG 0

#include <algorithm>

#include <ctime>

#include <fstream>

    const VsyncEventData& vsyncEventData = parcelableVsyncEventData.vsync;

    nsecs_t currentTime = systemTime();

    // Reset capture to present time offset if more than 1 second

    // between frames.

    if (t - mLastCaptureTime > kSpacingResetIntervalNs) {

    // Reset capture to present time offset if:

    // - More than 1 second between frames.

    // - The frame duration deviates from multiples of vsync frame intervals.

    nsecs_t captureInterval = t - mLastCaptureTime;

    float captureToVsyncIntervalRatio = 1.0f * captureInterval / vsyncEventData.frameInterval;

    float ratioDeviation = std::fabs(

            captureToVsyncIntervalRatio - std::roundf(captureToVsyncIntervalRatio));

    if (captureInterval > kSpacingResetIntervalNs ||

            ratioDeviation >= kMaxIntervalRatioDeviation) {

        nsecs_t minPresentT = mLastPresentTime + vsyncEventData.frameInterval / 2;

        for (size_t i = 0; i < VsyncEventData::kFrameTimelinesLength; i++) {

            if (vsyncEventData.frameTimelines[i].deadlineTimestamp >= currentTime) {

                mCaptureToPresentOffset =

                    vsyncEventData.frameTimelines[i].expectedPresentationTime - t;

                break;

            const auto& timeline = vsyncEventData.frameTimelines[i];

            if (timeline.deadlineTimestamp >= currentTime &&

                    timeline.expectedPresentationTime > minPresentT) {

                nsecs_t presentT = vsyncEventData.frameTimelines[i].expectedPresentationTime;

                mCaptureToPresentOffset = presentT - t;

                mLastCaptureTime = t;

                mLastPresentTime = presentT;

                // Move the expected presentation time back by 1/3 of frame interval to

                // mitigate the time drift. Due to time drift, if we directly use the

                // expected presentation time, often times 2 expected presentation time

                // falls into the same VSYNC interval.

                return presentT - vsyncEventData.frameInterval/3;

            }

        }

    }

    static constexpr size_t kDisplaySyncExtraBuffer = 2;

    static constexpr nsecs_t kSpacingResetIntervalNs = 1000000000LL; // 1 second

    static constexpr nsecs_t kTimelineThresholdNs = 1000000LL; // 1 millisecond

    static constexpr float kMaxIntervalRatioDeviation = 0.05f;

    nsecs_t syncTimestampToDisplayLocked(nsecs_t t);

    // Re-space frames by delaying queueBuffer so that frame delivery has