[libcamera-devel] [PATCH v4 12/14] ipa: ipu3: Cache line duration at configure call

[Kieran Bingham]

Quoting Jean-Michel Hautbois (2021-11-12 16:03:53)
> Hi Kieran,
> 
> On 12/11/2021 14:21, Kieran Bingham wrote:
> > Quoting Umang Jain (2021-11-12 12:36:21)
> >> Hi JM,
> >>
> >> On 11/11/21 7:39 PM, Jean-Michel Hautbois wrote:
> >>> We use the line duration several times in the IPAIPU3. Instead of
> >>> recalculating it each time, cache the value as a utils::Duration. When
> >>> the value is needed, cast it to a std::micro value.
> > 
> > Aren't values always 'needed' when they're obtained? This isn't quite
> > helping improve the clarity.
> > 
> > Why is it needed in micros, vs other usages?
> 
> OK, I may have to specify it is documented in 
> src/libcamera/control_ids.yaml ?
> 
> '''
> - ExposureTime:
>      type: int32_t
>      description: |
> Exposure time (shutter speed) for the frame applied in the sensor 
> device. This value is specified in micro-seconds.
> '''
> 
> How can I reference this file in the commit message ?

I don't think you need to reference the file, just the fact that
ExposureTime and FrameDuration units are in micro-seconds, and so the
Duration is cast accordingly.



> >>> As sensorInfo is no longer used in updateSessionConfiguration remove the
> >>> reference to it.
> >>>
> >>> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
> >>> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> >>
> >>
> >> Reviewed-by: Umang Jain <umang.jain at ideasonboard.com>
> >>
> >>> ---
> >>>    src/ipa/ipu3/ipu3.cpp | 29 +++++++++++++----------------
> >>>    1 file changed, 13 insertions(+), 16 deletions(-)
> >>>
> >>> diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
> >>> index d3195de6..f1597f78 100644
> >>> --- a/src/ipa/ipu3/ipu3.cpp
> >>> +++ b/src/ipa/ipu3/ipu3.cpp
> >>> @@ -148,8 +148,7 @@ private:
> >>>        void updateControls(const IPACameraSensorInfo &sensorInfo,
> >>>                            const ControlInfoMap &sensorControls,
> >>>                            ControlInfoMap *ipaControls);
> >>> -     void updateSessionConfiguration(const IPACameraSensorInfo &sensorInfo,
> >>> -                                     const ControlInfoMap &sensorControls);
> >>> +     void updateSessionConfiguration(const ControlInfoMap &sensorControls);
> >>>        void processControls(unsigned int frame, const ControlList &controls);
> >>>        void fillParams(unsigned int frame, ipu3_uapi_params *params);
> >>>        void parseStatistics(unsigned int frame,
> >>> @@ -174,6 +173,8 @@ private:
> >>>        uint32_t minGain_;
> >>>        uint32_t maxGain_;
> >>>    
> >>> +     utils::Duration lineDuration_;
> >>> +
> >>>        /* Interface to the Camera Helper */
> >>>        std::unique_ptr<CameraSensorHelper> camHelper_;
> >>>    
> >>> @@ -188,16 +189,12 @@ private:
> >>>     * \brief Compute IPASessionConfiguration using the sensor information and the
> >>>     * sensor V4L2 controls
> >>>     */
> >>> -void IPAIPU3::updateSessionConfiguration(const IPACameraSensorInfo &sensorInfo,
> >>> -                                      const ControlInfoMap &sensorControls)
> >>> +void IPAIPU3::updateSessionConfiguration(const ControlInfoMap &sensorControls)
> >>>    {
> >>>        const ControlInfo &v4l2Exposure = sensorControls.find(V4L2_CID_EXPOSURE)->second;
> >>>        int32_t minExposure = v4l2Exposure.min().get<int32_t>();
> >>>        int32_t maxExposure = v4l2Exposure.max().get<int32_t>();
> >>>    
> >>> -     utils::Duration lineDuration = sensorInfo.lineLength * 1.0s
> >>> -                                  / sensorInfo.pixelRate;
> >>> -
> >>>        const ControlInfo &v4l2Gain = sensorControls.find(V4L2_CID_ANALOGUE_GAIN)->second;
> >>>        int32_t minGain = v4l2Gain.min().get<int32_t>();
> >>>        int32_t maxGain = v4l2Gain.max().get<int32_t>();
> >>> @@ -209,8 +206,8 @@ void IPAIPU3::updateSessionConfiguration(const IPACameraSensorInfo &sensorInfo,
> >>>         *
> >>>         * \todo take VBLANK into account for maximum shutter speed
> >>>         */
> >>> -     context_.configuration.agc.minShutterSpeed = minExposure * lineDuration;
> >>> -     context_.configuration.agc.maxShutterSpeed = maxExposure * lineDuration;
> >>> +     context_.configuration.agc.minShutterSpeed = minExposure * lineDuration_;
> >>> +     context_.configuration.agc.maxShutterSpeed = maxExposure * lineDuration_;
> >>>        context_.configuration.agc.minAnalogueGain = camHelper_->gain(minGain);
> >>>        context_.configuration.agc.maxAnalogueGain = camHelper_->gain(maxGain);
> >>>    }
> >>> @@ -239,11 +236,10 @@ void IPAIPU3::updateControls(const IPACameraSensorInfo &sensorInfo,
> >>>         * exposure min, max and default and convert it from lines to
> >>>         * microseconds.
> >>>         */
> >>> -     double lineDuration = sensorInfo.lineLength / (sensorInfo.pixelRate / 1e6);
> >>>        const ControlInfo &v4l2Exposure = sensorControls.find(V4L2_CID_EXPOSURE)->second;
> >>> -     int32_t minExposure = v4l2Exposure.min().get<int32_t>() * lineDuration;
> >>> -     int32_t maxExposure = v4l2Exposure.max().get<int32_t>() * lineDuration;
> >>> -     int32_t defExposure = v4l2Exposure.def().get<int32_t>() * lineDuration;
> >>> +     int32_t minExposure = v4l2Exposure.min().get<int32_t>() * lineDuration_.get<std::micro>();
> >>> +     int32_t maxExposure = v4l2Exposure.max().get<int32_t>() * lineDuration_.get<std::micro>();
> >>> +     int32_t defExposure = v4l2Exposure.def().get<int32_t>() * lineDuration_.get<std::micro>();
> >>>        controls[&controls::ExposureTime] = ControlInfo(minExposure, maxExposure,
> >>>                                                        defExposure);
> >>>    
> >>> @@ -463,11 +459,13 @@ int IPAIPU3::configure(const IPAConfigInfo &configInfo,
> >>>    
> >>>        calculateBdsGrid(configInfo.bdsOutputSize);
> >>>    
> >>> +     lineDuration_ = sensorInfo_.lineLength * 1.0s / sensorInfo_.pixelRate;
> >>> +
> >>>        /* Update the camera controls using the new sensor settings. */
> >>>        updateControls(sensorInfo_, ctrls_, ipaControls);
> >>>    
> >>>        /* Update the IPASessionConfiguration using the sensor settings. */
> >>> -     updateSessionConfiguration(sensorInfo_, ctrls_);
> >>> +     updateSessionConfiguration(ctrls_);
> >>>    
> >>>        for (auto const &algo : algorithms_) {
> >>>                int ret = algo->configure(context_, configInfo);
> >>> @@ -627,8 +625,7 @@ void IPAIPU3::parseStatistics(unsigned int frame,
> >>>        setControls(frame);
> >>>    
> >>>        /* \todo Use VBlank value calculated from each frame exposure. */
> >>> -     int64_t frameDuration = sensorInfo_.lineLength * (defVBlank_ + sensorInfo_.outputSize.height) /
> >>> -                             (sensorInfo_.pixelRate / 1e6);
> >>> +     int64_t frameDuration = (defVBlank_ + sensorInfo_.outputSize.height) * lineDuration_.get<std::micro>();
> >>>        ctrls.set(controls::FrameDuration, frameDuration);
> >>>    
> >>>        ctrls.set(controls::ColourTemperature, context_.frameContext.awb.temperatureK);