From 5e8c41ce4ed8c013234e03a067bc7dcac6cb287e Mon Sep 17 00:00:00 2001 From: Daniel Semkowicz via libcamera-devel Date: Wed, 13 Jul 2022 10:43:15 +0200 Subject: ipa: af_hill_climb: Skip the first frame after triggering auto focus When AFTrigger is received, AF algorithm internal state is reset to initial values. If reset happens between frames, then first contrast value that arrives after this, is interpreted as contrast for initial position. This is wrong, because it was measured for lens position before the reset. Skip this first frame to allow correct contrast measure for the initial lens position. Signed-off-by: Daniel Semkowicz --- src/ipa/libipa/algorithms/af_hill_climbing.cpp | 8 ++++++++ src/ipa/libipa/algorithms/af_hill_climbing.h | 23 ++++++++++++++++++++++- 2 files changed, 30 insertions(+), 1 deletion(-) (limited to 'src/ipa/libipa') diff --git a/src/ipa/libipa/algorithms/af_hill_climbing.cpp b/src/ipa/libipa/algorithms/af_hill_climbing.cpp index f666c6c2..28d09176 100644 --- a/src/ipa/libipa/algorithms/af_hill_climbing.cpp +++ b/src/ipa/libipa/algorithms/af_hill_climbing.cpp @@ -84,6 +84,14 @@ namespace ipa::common::algorithms { * \return New lens position calculated by AF algorithm */ +/** + * \fn AfHillClimbing::setFramesToSkip() + * \brief Request AF to skip n frames + * \param[in] n Number of frames to be skipped + * + * Requested number of frames will not be used for AF calculation. + */ + } /* namespace ipa::common::algorithms */ } /* namespace libcamera */ diff --git a/src/ipa/libipa/algorithms/af_hill_climbing.h b/src/ipa/libipa/algorithms/af_hill_climbing.h index db9fc058..e251f3eb 100644 --- a/src/ipa/libipa/algorithms/af_hill_climbing.h +++ b/src/ipa/libipa/algorithms/af_hill_climbing.h @@ -29,7 +29,7 @@ public: lensPosition_(0), bestPosition_(0), currentContrast_(0.0), previousContrast_(0.0), maxContrast_(0.0), maxStep_(0), coarseCompleted_(false), fineCompleted_(false), - lowStep_(0), highStep_(kMaxFocusSteps) + lowStep_(0), highStep_(kMaxFocusSteps), framesToSkip_(0) { } @@ -92,6 +92,9 @@ protected: { currentContrast_ = currentContrast; + if (shouldSkipFrame()) + return lensPosition_; + /* If we are in a paused state, we won't process the stats */ if (pauseState_ == libcamera::controls::AfPauseStatePaused) return lensPosition_; @@ -113,6 +116,12 @@ protected: return lensPosition_; } + void setFramesToSkip(uint32_t n) + { + if (n > framesToSkip_) + framesToSkip_ = n; + } + private: void afCoarseScan() { @@ -191,6 +200,7 @@ private: coarseCompleted_ = false; fineCompleted_ = false; maxContrast_ = 0.0; + setFramesToSkip(1); } bool afIsOutOfFocus() @@ -206,6 +216,16 @@ private: return false; } + bool shouldSkipFrame() + { + if (framesToSkip_ > 0) { + framesToSkip_--; + return true; + } + + return false; + } + controls::AfModeEnum mode_; controls::AfStateEnum state_; controls::AfPauseStateEnum pauseState_; @@ -229,6 +249,7 @@ private: uint32_t lowStep_; uint32_t highStep_; + uint32_t framesToSkip_; /* * Maximum focus steps of the VCM control -- cgit v1.2.1