SurfaceFlinger: better fit content to refresh rate
Enhance the current algorithm for content based refresh rate selection
to choose a refresh rate that aligns better to the content. If no refresh
rate fits to the content we choose the lower one.
Fixes: 129874336
Test: Swappy render at 90fps, 45fps, 30fps
Test: Youtube video playback on 24fps, 25fps, 30fps, and 60fps
Change-Id: Ia6b1f2a1d78e257e0de99ba12c14ca3721b4ad26
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 073a2db..b1c39ef 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -405,23 +405,34 @@
}
// Content detection is on, find the appropriate refresh rate
- // Start with the smallest refresh rate which is greater than the content
+ // Start with the smallest refresh rate which is within a margin of the content
+ RefreshRateType currRefreshRateType = RefreshRateType::PERFORMANCE;
+ constexpr float MARGIN = 0.05f;
auto iter = mRefreshRateConfigs.getRefreshRates().cbegin();
- RefreshRateType currRefreshRateType = iter->first;
while (iter != mRefreshRateConfigs.getRefreshRates().cend()) {
- if (iter->second->fps >= mContentRefreshRate) {
+ if (iter->second->fps >= mContentRefreshRate * (1 - MARGIN)) {
currRefreshRateType = iter->first;
break;
}
++iter;
}
- if (iter == mRefreshRateConfigs.getRefreshRates().cend()) {
- return RefreshRateType::PERFORMANCE;
- }
+ // Some content aligns better on higher refresh rate. For example for 45fps we should choose
+ // 90Hz config. However we should still prefer a lower refresh rate if the content doesn't
+ // align well with both
+ float ratio = mRefreshRateConfigs.getRefreshRate(currRefreshRateType)->fps /
+ float(mContentRefreshRate);
+ if (std::abs(std::round(ratio) - ratio) > MARGIN) {
+ while (iter != mRefreshRateConfigs.getRefreshRates().cend()) {
+ ratio = iter->second->fps / float(mContentRefreshRate);
- // TODO(b/129874336): This logic is sub-optimal for content refresh rate that aligns better
- // with a higher refresh rate. For example for 45fps we should choose 90Hz config.
+ if (std::abs(std::round(ratio) - ratio) <= MARGIN) {
+ currRefreshRateType = iter->first;
+ break;
+ }
+ ++iter;
+ }
+ }
return currRefreshRateType;
}