[libcamera-devel] [PATCH v2 1/6] libcamera: controls: Specify manual gain units and change exposure units

[Kieran Bingham]

On 20/03/2020 14:05, Laurent Pinchart wrote:
> Hi Kieran,
> 
> On Fri, Mar 20, 2020 at 01:38:02PM +0000, Kieran Bingham wrote:
>> On 09/03/2020 12:33, Naushir Patuck wrote:
>>> Use micro-seconds for ManualExposure. This is changed from milli-
>>> seconds. The latter would not allow very low exposure times.
>>>
>>> ManualGain switch to use a float to allow fractional gain adjustments.
>>
>> "Switch ManualGain to use a float" ...?
>>
>>> Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
>>> ---
>>>  src/libcamera/control_ids.yaml | 13 ++++++++++---
>>>  1 file changed, 10 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
>>> index 4befec74..5bbe65ae 100644
>>> --- a/src/libcamera/control_ids.yaml
>>> +++ b/src/libcamera/control_ids.yaml
>>> @@ -44,10 +44,17 @@ controls:
>>>  
>>>    - ManualExposure:
>>>        type: int32_t
>>
>> Not directly against this patch, but I can't imagine having a negative
>> exposure time - so should this be uint32_t?
> 
> We don't have unsigned int controls :-)

Ah well then I guess we can't use a uint32_t ...

Is that just a restriction due to ControlValue templates?
Presumably we 'could' have them - but maybe it's not needed.

> 
>>> -      description: Specify a fixed exposure time in milli-seconds
>>> +      description: |
>>> +        Specify a fixed exposure time in micro-seconds to be applied in the
>>> +        sensor device.
>>> +
>>> +        \sa ManualGain
>>>  
>>>    - ManualGain:
>>> -      type: int32_t
>>> -      description: Specify a fixed gain parameter
>>> +      type: float
>>> +      description: |
>>> +        Specify a fixed gain value to be applied in the pipeline.  This gain is
>>> +        applied to all colour channels.
>>>  
>>> +        \sa ManualExposure
>>>  ...
>>>
>>
>> Otherwise, this sounds good to me.
>>
>> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> 

-- 
Regards
--
Kieran