libcamera: formats: Add ImageFormats

Add a new class to hold format information for V4L2 devices and
subdevices. The object describes the relationship between either pixel
formats (V4L2 devices) or media bus codes (V4L2 subdevice) and a list of
image sizes which can be produced with that format.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/libcamera/include/formats.h

@@ -17,6 +17,20 @@ namespace libcamera {
 
 typedef std::map<unsigned int, std::vector<SizeRange>> FormatEnum;
 
+class ImageFormats
+{
+public:
+	int addFormat(unsigned int format, const std::vector<SizeRange> &sizes);
+
+	bool isEmpty() const;
+	std::vector<unsigned int> formats() const;
+	const std::vector<SizeRange> &sizes(unsigned int format) const;
+	const std::map<unsigned int, std::vector<SizeRange>> &data() const;
+
+private:
+	std::map<unsigned int, std::vector<SizeRange>> data_;
+};
+
 } /* namespace libcamera */
 
 #endif /* __LIBCAMERA_FORMATS_H__ */