From 92b8ccc42a0f3ad323c79bde3c132d6956011239 Mon Sep 17 00:00:00 2001 From: Naushir Patuck Date: Tue, 19 Jan 2021 15:30:46 +0000 Subject: libcamera: raspberrypi: Add control of sensor vblanking Add support for setting V4L2_CID_VBLANK appropriately when setting V4L2_CID_EXPOSURE. This will allow adaptive framerates during viewfinder use cases (e.g. when the exposure time goes above 33ms, we can reduce the framerate to lower than 30fps). The minimum and maximum frame durations are provided via libcamera controls, and will prioritise exposure time limits over any AGC request. V4L2_CID_VBLANK is controlled through the staggered writer, just like the exposure and gain controls. Signed-off-by: Naushir Patuck Reviewed-by: David Plowman Tested-by: David Plowman Reviewed-by: Jacopo Mondi Reviewed-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- src/ipa/raspberrypi/cam_helper_imx477.cpp | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'src/ipa/raspberrypi/cam_helper_imx477.cpp') diff --git a/src/ipa/raspberrypi/cam_helper_imx477.cpp b/src/ipa/raspberrypi/cam_helper_imx477.cpp index 0e896ac7..53961310 100644 --- a/src/ipa/raspberrypi/cam_helper_imx477.cpp +++ b/src/ipa/raspberrypi/cam_helper_imx477.cpp @@ -38,10 +38,19 @@ public: uint32_t GainCode(double gain) const override; double Gain(uint32_t gain_code) const override; bool SensorEmbeddedDataPresent() const override; + +private: + /* + * Smallest difference between the frame length and integration time, + * in units of lines. + */ + static constexpr int frameIntegrationDiff = 22; + /* Largest possible frame length, in units of lines. */ + static constexpr int maxFrameLength = 0xffdc; }; CamHelperImx477::CamHelperImx477() - : CamHelper(new MdParserImx477()) + : CamHelper(new MdParserImx477(), maxFrameLength, frameIntegrationDiff) { } -- cgit v1.2.1