[libcamera-devel] [PATCH 1/2] libipa: Add CameraSensorHelper for ov2680

[Daniel Scally]

Hi Laurent

On 30/11/2021 21:56, Laurent Pinchart wrote:
> Hi Daniel,
> 
> Thank you for the patch.
> 
> On Tue, Nov 30, 2021 at 09:34:10PM +0000, Daniel Scally wrote:
>> Add a CameraSensorHelperOv2680 class. The OV2680 is found in concert
>> with an IPU3 on the Lenovo Miix 510. The constants set are a bit of a
>> guess, as the datasheet doesn't document the gain control field any
>> further than giving its width in bits, but the default is 0x10 so we
>> assume that to be 1x gain.
> 
> Would you be able to test if the gain is linear by capturing images
> with, for instance, gains set to 16, 32, 48 and 64 and see if the
> average relative luminance increases linearly ?

Sure; judging by eye you mean, or something more sophisticated?
> 
>> Signed-off-by: Daniel Scally <djrscally at gmail.com>
>> ---
>>  src/ipa/libipa/camera_sensor_helper.cpp | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/src/ipa/libipa/camera_sensor_helper.cpp b/src/ipa/libipa/camera_sensor_helper.cpp
>> index 0b0eb503..fd951505 100644
>> --- a/src/ipa/libipa/camera_sensor_helper.cpp
>> +++ b/src/ipa/libipa/camera_sensor_helper.cpp
>> @@ -305,6 +305,16 @@ public:
>>  };
>>  REGISTER_CAMERA_SENSOR_HELPER("imx258", CameraSensorHelperImx258)
>>  
>> +class CameraSensorHelperOv2680 : public CameraSensorHelper
>> +{
>> +public:
>> +	CameraSensorHelperOv2680()
>> +	{
>> +		analogueGainConstants_ = { AnalogueGainLinear, 1, 0, 0, 16 };
>> +	}
>> +};
>> +REGISTER_CAMERA_SENSOR_HELPER("ov2680", CameraSensorHelperOv2680)
>> +
>>  class CameraSensorHelperOv5670 : public CameraSensorHelper
>>  {
>>  public:
>