[libcamera-devel] [PATCH] libipa: Correct OV5670 CameraSensorHelper gain values

[Jean-Michel Hautbois]

The datasheet states that the low 7 bits are fraction bits.
real_gain = GainCode/128
For example, 0x080 is 1x gain, 0x100 is 2x gain.

It means that we should have m0=1 and c1=128.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
---
 src/ipa/libipa/camera_sensor_helper.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ipa/libipa/camera_sensor_helper.cpp b/src/ipa/libipa/camera_sensor_helper.cpp
index 17e4f0b2..709835a8 100644
--- a/src/ipa/libipa/camera_sensor_helper.cpp
+++ b/src/ipa/libipa/camera_sensor_helper.cpp
@@ -300,7 +300,7 @@ class CameraSensorHelperOv5670 : public CameraSensorHelper
 public:
 	CameraSensorHelperOv5670()
 	{
-		analogueGainConstants_ = { AnalogueGainLinear, 1, 0, 0, 256 };
+		analogueGainConstants_ = { AnalogueGainLinear, 1, 0, 0, 128 };
 	}
 };
 REGISTER_CAMERA_SENSOR_HELPER("ov5670", CameraSensorHelperOv5670)
-- 
2.30.2