[libcamera-devel] [PATCH v8 7/8] libcamera: Add validateColorSpaces to CameraConfiguration class

[Jacopo Mondi]

Hi David

On Wed, Dec 01, 2021 at 03:44:33PM +0000, David Plowman wrote:
> This method forces raw streams to have the "raw" color space, and also
> optionally makes all output streams to share the same color space as
> some platforms may require this.
>
> Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
> ---
>  include/libcamera/camera.h |  2 ++
>  src/libcamera/camera.cpp   | 69 ++++++++++++++++++++++++++++++++++++++
>  2 files changed, 71 insertions(+)
>
> diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h
> index a7759ccb..fdcb66ab 100644
> --- a/include/libcamera/camera.h
> +++ b/include/libcamera/camera.h
> @@ -69,6 +69,8 @@ public:
>  protected:
>  	CameraConfiguration();
>
> +	Status validateColorSpaces(bool shareOutputColorSpaces);
> +
>  	std::vector<StreamConfiguration> config_;
>  };
>
> diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
> index 400a7cf0..a6a93dd0 100644
> --- a/src/libcamera/camera.cpp
> +++ b/src/libcamera/camera.cpp
> @@ -14,12 +14,14 @@
>  #include <libcamera/base/log.h>
>  #include <libcamera/base/thread.h>
>
> +#include <libcamera/color_space.h>
>  #include <libcamera/framebuffer_allocator.h>
>  #include <libcamera/request.h>
>  #include <libcamera/stream.h>
>
>  #include "libcamera/internal/camera.h"
>  #include "libcamera/internal/camera_controls.h"
> +#include "libcamera/internal/formats.h"
>  #include "libcamera/internal/pipeline_handler.h"
>
>  /**
> @@ -314,6 +316,73 @@ std::size_t CameraConfiguration::size() const
>  	return config_.size();
>  }
>
> +static bool isRaw(const PixelFormat &pixFmt)
> +{
> +	const PixelFormatInfo &info = PixelFormatInfo::info(pixFmt);
> +	return info.isValid() &&
> +	       info.colourEncoding == PixelFormatInfo::ColourEncodingRAW;
> +}
> +
> +/**
> + * \brief Check the color spaces requested for each stream

Check and update

> + * \param[in] shareOutputColorSpaces Force all output streams to share the same
> + * color space

The non-RAW output streams ?

> + *
> + * This function performs certain consistency checks on the color spaces of
> + * the streams and may adjust them so that:
> + *
> + * - Any raw streams have the Raw color space
> + * - If shareOutputColorSpaces is set, all output streams are forced to share
> + * the same color space (this may be a constraint on some platforms).
> + *
> + * It is optional for a pipeline handler to use this method.
> + *
> + * \return A CameraConfiguration::Status value that describes the validation
> + * status.
> + * \retval CameraConfiguration::Invalid The configuration is invalid and can't
> + * be adjusted. This may only occur in extreme cases such as when the
> + * configuration is empty.
> + * \retval CameraConfigutation::Adjusted The configuration has been adjusted
> + * and is now valid. Parameters may have changed for any stream, and stream
> + * configurations may have been removed. The caller shall check the
> + * configuration carefully.
> + * \retval CameraConfiguration::Valid The configuration was already valid and
> + * hasn't been adjusted.

Thanks for the detailed documentation of the return values, much
apreciated. I think you could have saved it though, as
CameraConfiguration::Status is fully documented, so it's enough to say
we return that.

> + */
> +CameraConfiguration::Status CameraConfiguration::validateColorSpaces(bool shareOutputColorSpaces)
> +{
> +	Status status = Valid;
> +
> +	/*
> +	 * Set all raw streams to the Raw color space, and make a note of the largest
> +	 * non-raw stream with a defined color space (if there is one).
> +	 */
> +	int index = -1;
> +	for (auto [i, cfg] : utils::enumerate(config_)) {
> +		if (isRaw(cfg.pixelFormat)) {
> +			if (cfg.colorSpace != ColorSpace::Raw) {
> +				cfg.colorSpace = ColorSpace::Raw;
> +				status = Adjusted;
> +		}
> +		else if (cfg.colorSpace && (index == -1 || cfg.size > config_[i].size))
> +			index = i;
> +	}
> +
> +	if (index < 0 || !shareOutputColorSpaces)
> +		return status;
> +
> +	/* Make all output color spaces the same, if requested. */
> +	for (auto &cfg : config_) {
> +		if (!isRaw(cfg.pixelFormat) &&
> +		    cfg.colorSpace != config_[index].colorSpace) {
> +			cfg.colorSpace = config_[index].colorSpace;
> +			status = Adjusted;
> +		}
> +	}
> +
> +	return status;
> +}
> +

Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>

Thanks
  j

>  /**
>   * \var CameraConfiguration::transform
>   * \brief User-specified transform to be applied to the image
> --
> 2.30.2
>