[libcamera-devel] [PATCH 2/3] ipa: ipu3: Mark the beginning and end of a frame

[Umang Jain]

Hi Kieran

On 4/21/22 16:16, Kieran Bingham wrote:
> Quoting Umang Jain (2022-03-10 20:51:29)
>> From: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
>>
>> Introduce the skeleton for two functions which will be used to
>> instantiate a frame context, and do everything needed when a frame is
>> received. Do the same for the other end, once the algorithms have run
>> and updated the frame context to later deallocate the corresponding
>> frame context.
>>
>> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
>> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
>> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
>> ---
>>   src/ipa/ipu3/ipu3.cpp | 20 ++++++++++++++++++++
>>   1 file changed, 20 insertions(+)
>>
>> diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
>> index 81788b9a..3d5c5706 100644
>> --- a/src/ipa/ipu3/ipu3.cpp
>> +++ b/src/ipa/ipu3/ipu3.cpp
>> @@ -163,6 +163,14 @@ private:
>>          void setControls(unsigned int frame);
>>          void calculateBdsGrid(const Size &bdsOutputSize);
>>   
>> +       /*
>> +        * Internal events that mark the beginning of processing a new frame
>> +        * to the point that it has successfully completed processing its
>> +        * statistics.
>> +        */
>> +       void frameStarted(const uint32_t frame);
>> +       void frameCompleted(const uint32_t frame);
>> +
>>          std::map<unsigned int, MappedFrameBuffer> buffers_;
>>   
>>          ControlInfoMap ctrls_;
>> @@ -491,6 +499,14 @@ void IPAIPU3::unmapBuffers(const std::vector<unsigned int> &ids)
>>          }
>>   }
>>   
>> +void IPAIPU3::frameStarted([[maybe_unused]] const uint32_t frame)
>> +{
>> +}
>> +
>> +void IPAIPU3::frameCompleted([[maybe_unused]] const uint32_t frame)
>> +{
>> +}
>> +
>>   /**
>>    * \brief Prepare the ISP to process the Request
>>    * \param[in] frame The frame number
>> @@ -549,6 +565,8 @@ void IPAIPU3::processControls(const uint32_t frame,
>>                                [[maybe_unused]] const ControlList &controls)
> Aha, I was a bit confused, but I think this is now called queueRequest()


Yep, this will go under a major rebase to adapt to new interface.

>
> It will be interesting to see how we tie up a request that is queued to
> the frame index that it will capture from. I think it works out in the


Discussion is under progress. Either we can tie up Request sequence with 
frame number

OR

for the HAL case, the Camera3RequestDescriptor gets a frame number/id 
from the framework. I am keen to use that too but for non-HAL cases it 
won't suffice (or I need to develop an alternative mechanism)

https://git.libcamera.org/libcamera/libcamera.git/tree/include/android/hardware/libhardware/include/hardware/camera3.h#n2228


> end, as long as we ensure that requests are queued before we start the
> camera ...
>
> (and now I can't recall, do we support starting the camera without
> requests queued?...)


Initially we dont.

But if there is a start/stop sequence, I think on next start, the 
request already queued will get satisfied first?

>
>
>>   {
>>          /* \todo Start processing for 'frame' based on 'controls'. */
>> +
>> +       frameStarted(frame);
>>   }
>>   
>>   /**
>> @@ -620,6 +638,8 @@ void IPAIPU3::parseStatistics(unsigned int frame,
>>           */
>>   
>>          statsBufferReady.emit(frame, ctrls);
>> +
>> +       frameCompleted(frame);
>>   }
>>   
>>   /**
>> -- 
>> 2.31.0
>>