libcamera: converter: Add functions to adjust config

Add to the Converter interface two functions used by pipeline handlers
to validate and adjust the converter input and output configurations
by specifying the desired alignment for the adjustment.

Add the adjustInputSize() and adjustOutputSize() functions that allows
to adjust the converter input/output sizes with the desired alignment.

Add a validateOutput() function meant to be used by the pipeline
handler implementations of validate(). The function adjusts a
StreamConfiguration to a valid configuration produced by the Converter.

Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Stefan Klug <stefan.klug@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com>

2 files changed, 26 insertions, 0 deletions

diff --git a/include/libcamera/internal/converter.h b/include/libcamera/internal/converter.h
index afea4624..644ec429 100644
--- a/include/libcamera/internal/converter.h
+++ b/include/libcamera/internal/converter.h
@@ -41,6 +41,11 @@ public:
 
 	using Features = Flags<Feature>;
 
+	enum class Alignment {
+		Down = 0,
+		Up,
+	};
+
 	Converter(MediaDevice *media, Features features = Feature::None);
 	virtual ~Converter();
 
@@ -51,9 +56,19 @@ public:
 	virtual std::vector<PixelFormat> formats(PixelFormat input) = 0;
 	virtual SizeRange sizes(const Size &input) = 0;
 
+	virtual Size adjustInputSize(const PixelFormat &pixFmt,
+				     const Size &size,
+				     Alignment align = Alignment::Down) = 0;
+	virtual Size adjustOutputSize(const PixelFormat &pixFmt,
+				      const Size &size,
+				      Alignment align = Alignment::Down) = 0;
+
 	virtual std::tuple<unsigned int, unsigned int>
 	strideAndFrameSize(const PixelFormat &pixelFormat, const Size &size) = 0;
 
+	virtual int validateOutput(StreamConfiguration *cfg, bool *adjusted,
+				   Alignment align = Alignment::Down) = 0;
+
 	virtual int configure(const StreamConfiguration &inputCfg,
 			      const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfgs) = 0;
 	virtual bool isConfigured(const Stream *stream) const = 0;
diff --git a/include/libcamera/internal/converter/converter_v4l2_m2m.h b/include/libcamera/internal/converter/converter_v4l2_m2m.h
index 1ccbfc7c..0ad7bf7f 100644
--- a/include/libcamera/internal/converter/converter_v4l2_m2m.h
+++ b/include/libcamera/internal/converter/converter_v4l2_m2m.h
@@ -47,6 +47,11 @@ public:
 	std::tuple<unsigned int, unsigned int>
 	strideAndFrameSize(const PixelFormat &pixelFormat, const Size &size) override;
 
+	Size adjustInputSize(const PixelFormat &pixFmt,
+			     const Size &size, Alignment align = Alignment::Down) override;
+	Size adjustOutputSize(const PixelFormat &pixFmt,
+			      const Size &size, Alignment align = Alignment::Down) override;
+
 	int configure(const StreamConfiguration &inputCfg,
 		      const std::vector<std::reference_wrapper<StreamConfiguration>>
 		      &outputCfg) override;
@@ -57,6 +62,9 @@ public:
 	int start() override;
 	void stop() override;
 
+	int validateOutput(StreamConfiguration *cfg, bool *adjusted,
+			   Alignment align = Alignment::Down) override;
+
 	int queueBuffers(FrameBuffer *input,
 			 const std::map<const Stream *, FrameBuffer *> &outputs) override;
 
@@ -104,6 +112,9 @@ private:
 		std::pair<Rectangle, Rectangle> inputCropBounds_;
 	};
 
+	Size adjustSizes(const Size &size, const std::vector<SizeRange> &ranges,
+			 Alignment align);
+
 	std::unique_ptr<V4L2M2MDevice> m2m_;
 
 	std::map<const Stream *, std::unique_ptr<V4L2M2MStream>> streams_;