[libcamera-devel] [PATCH v5 6/7] libcamera: Add validateColorSpaces to CameraConfiguration class

[David Plowman]

This method checks that the requested color spaces are sensible and do
not contain any undefined enum values. It also initialises the
"actual" color space field to the same value as the one requested, in
the expectation that the rest of the validate() method will be able to
check this.

Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
Reviewed-by: Naushir Patuck <naush at raspberrypi.com>
---
 include/libcamera/camera.h |  2 ++
 src/libcamera/camera.cpp   | 51 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h
index 601ee46e..fdab4410 100644
--- a/include/libcamera/camera.h
+++ b/include/libcamera/camera.h
@@ -69,6 +69,8 @@ public:
 protected:
 	CameraConfiguration();
 
+	Status validateColorSpaces(bool sharedColorSpace);
+
 	std::vector<StreamConfiguration> config_;
 };
 
diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index 400a7cf0..90e9460b 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -20,6 +20,7 @@
 
 #include "libcamera/internal/camera.h"
 #include "libcamera/internal/camera_controls.h"
+#include "libcamera/internal/formats.h"
 #include "libcamera/internal/pipeline_handler.h"
 
 /**
@@ -314,6 +315,56 @@ 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;
+}
+
+CameraConfiguration::Status CameraConfiguration::validateColorSpaces(bool sharedColorSpace)
+{
+	Status status = Valid;
+
+	/* Find the largest non-raw stream (if any). */
+	int index = -1;
+	for (unsigned int i = 0; i < config_.size(); i++) {
+		const StreamConfiguration &cfg = config_[i];
+		if (!isRaw(cfg.pixelFormat) && (index < 0 || cfg.size > config_[i].size))
+			index = i;
+	}
+
+	/*
+	 * Here we force raw streams to the correct color space and signal
+	 * an error if we encounter anything undefined. We handle the case
+	 * where all output streams are to share a color space, which we
+	 * choose to be the color space of the largest stream.
+	 */
+	for (auto &cfg : config_) {
+		ColorSpace initialColorSpace = cfg.requestedColorSpace;
+
+		if (isRaw(cfg.pixelFormat))
+			cfg.requestedColorSpace = ColorSpace::Raw;
+		else if (!cfg.requestedColorSpace.isFullyDefined()) {
+			LOG(Camera, Error) << "Stream has undefined color space";
+			cfg.requestedColorSpace = ColorSpace::Jpeg;
+		} else if (sharedColorSpace)
+			cfg.requestedColorSpace = config_[index].requestedColorSpace;
+
+		if (cfg.requestedColorSpace != initialColorSpace)
+			status = Adjusted;
+
+		/*
+		 * We also initialise the actual color space as if the
+		 * hardware can do what we want. But note that the rest
+		 * of the validate() method may change this.
+		 */
+		cfg.actualColorSpace = cfg.requestedColorSpace;
+	}
+
+	return status;
+}
+
 /**
  * \var CameraConfiguration::transform
  * \brief User-specified transform to be applied to the image
-- 
2.20.1