[libcamera-devel] [PATCH 3/4] libcamera: camera_sensor: Add function to apply a config

[Naushir Patuck]

Hi Jacopo,

Thank you for your work.

On Mon, 24 Jul 2023 at 13:39, Jacopo Mondi via libcamera-devel
<libcamera-devel at lists.libcamera.org> wrote:
>
> Add to the CameraSensor class a function to apply to the sensor
> a full configuration.
>
> The configuration shall be fully populated and shall apply without
> modifications to the sensor.
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi at ideasonboard.com>

Reviewed-by: Naushir Patuck <naush at raspberrypi.com>

> ---
>  include/libcamera/internal/camera_sensor.h |  5 ++
>  src/libcamera/camera_sensor.cpp            | 86 ++++++++++++++++++++++
>  2 files changed, 91 insertions(+)
>
> diff --git a/include/libcamera/internal/camera_sensor.h b/include/libcamera/internal/camera_sensor.h
> index 02c77ab037da..06791c3c6425 100644
> --- a/include/libcamera/internal/camera_sensor.h
> +++ b/include/libcamera/internal/camera_sensor.h
> @@ -29,6 +29,7 @@ namespace libcamera {
>  class BayerFormat;
>  class CameraLens;
>  class MediaEntity;
> +class SensorConfiguration;
>
>  struct CameraSensorProperties;
>
> @@ -58,6 +59,10 @@ public:
>                       Transform transform = Transform::Identity);
>         int tryFormat(V4L2SubdeviceFormat *format) const;
>
> +       int applyConfiguration(const SensorConfiguration &config,
> +                              Transform transform = Transform::Identity,
> +                              V4L2SubdeviceFormat *sensorFormat = nullptr);
> +
>         const ControlInfoMap &controls() const;
>         ControlList getControls(const std::vector<uint32_t> &ids);
>         int setControls(ControlList *ctrls);
> diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
> index f3a5aa37149f..96b618572a3d 100644
> --- a/src/libcamera/camera_sensor.cpp
> +++ b/src/libcamera/camera_sensor.cpp
> @@ -15,6 +15,7 @@
>  #include <math.h>
>  #include <string.h>
>
> +#include <libcamera/camera.h>
>  #include <libcamera/property_ids.h>
>
>  #include <libcamera/base/utils.h>
> @@ -822,6 +823,91 @@ int CameraSensor::tryFormat(V4L2SubdeviceFormat *format) const
>                                   V4L2Subdevice::Whence::TryFormat);
>  }
>
> +/**
> + * \brief Apply a sensor configuration to the camera sensor
> + * \param[in] config The sensor configuration
> + * \param[in] transform The transform to be applied on the sensor.
> + * Defaults to Identity
> + * \param[out] sensorFormat Optional output parameter where the format
> + * actually applied to the sensor is returned to the caller
> + *
> + * Apply to the camera sensor the configuration \a config.
> + *
> + * \todo The configuration shall be fully populated and if any of the fields
> + * there specified cannot be applied as it is, an error code is returned.
> + *
> + * \return 0 if \a config is applied to the camera sensor, a negative error code
> + * otherwise
> + */
> +int CameraSensor::applyConfiguration(const SensorConfiguration &config,
> +                                    Transform transform,
> +                                    V4L2SubdeviceFormat *sensorFormat)
> +{
> +       if (!config) {
> +               LOG(CameraSensor, Error) << "Invalid sensor configuration";
> +               return -EINVAL;
> +       }
> +
> +       std::vector<unsigned int> filteredCodes;
> +       std::copy_if(mbusCodes_.begin(), mbusCodes_.end(),
> +                    std::back_inserter(filteredCodes),
> +                    [&config](unsigned int mbusCode) {
> +                            BayerFormat bayer = BayerFormat::fromMbusCode(mbusCode);
> +                            if (bayer.bitDepth == config.bitDepth)
> +                                    return true;
> +                            return false;
> +                    });
> +       if (filteredCodes.empty()) {
> +               LOG(CameraSensor, Error)
> +                       << "Cannot find any format with bit depth "
> +                       << config.bitDepth;
> +               return -EINVAL;
> +       }
> +
> +       /*
> +        * Compute the sensor's data frame size by applying the cropping
> +        * rectangle, subsampling and output crop to the sensor's pixel array
> +        * size.
> +        *
> +        * \todo The actual size computation is for now ignored and only the
> +        * output size is considered. This implies that resolutions obtained
> +        * with two different cropping/subsampling will look identical and
> +        * only the first found one will be considered.
> +        */
> +       V4L2SubdeviceFormat subdevFormat = {};
> +       for (unsigned int code : filteredCodes) {
> +               for (const Size &size : sizes(code)) {
> +                       if (size.width != config.outputSize.width ||
> +                           size.height != config.outputSize.height)
> +                               continue;
> +
> +                       subdevFormat.mbus_code = code;
> +                       subdevFormat.size = size;
> +                       break;
> +               }
> +       }
> +       if (!subdevFormat.mbus_code) {
> +               LOG(CameraSensor, Error) << "Invalid output size in sensor configuration";
> +               return -EINVAL;
> +       }
> +
> +       int ret = setFormat(&subdevFormat, transform);
> +       if (ret)
> +               return ret;
> +
> +       /*
> +        * Return to the caller the format actually applied to the sensor.
> +        * This is relevant if transform has changed the bayer pattern order.
> +        */
> +       if (sensorFormat)
> +               *sensorFormat = subdevFormat;
> +
> +       /* \todo Handle AnalogCrop. Most sensors do not support set_selection */
> +       /* \todo Handle scaling in the digital domain. */
> +
> +       return 0;
> +}
> +
>  /**
>   * \brief Retrieve the supported V4L2 controls and their information
>   *
> --
> 2.40.1
>