[libcamera-devel] [PATCH] libcamera: formats: add planeCount helper

[Kieran Bingham]

Determine the number of planes used by a format by counting the number
of PxielFormatPlaneInfo entries with a valid entry.

Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---
 include/libcamera/internal/formats.h |  2 ++
 src/libcamera/formats.cpp            | 22 ++++++++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/include/libcamera/internal/formats.h b/include/libcamera/internal/formats.h
index 0bb151044294..beeaab1ae2f5 100644
--- a/include/libcamera/internal/formats.h
+++ b/include/libcamera/internal/formats.h
@@ -45,6 +45,8 @@ public:
 	unsigned int frameSize(const Size &size,
 			       const std::array<unsigned int, 3> &strides) const;
 
+	unsigned int planeCount() const;
+
 	/* \todo Add support for non-contiguous memory planes */
 	const char *name;
 	PixelFormat format;
diff --git a/src/libcamera/formats.cpp b/src/libcamera/formats.cpp
index cd63c15cb926..70d31fb36c37 100644
--- a/src/libcamera/formats.cpp
+++ b/src/libcamera/formats.cpp
@@ -805,4 +805,26 @@ PixelFormatInfo::frameSize(const Size &size,
 	return sum;
 }
 
+/**
+ * \brief Identify the number of planes represented by the format
+ *
+ * This function counts the number of planes which have a valid configuration
+ * and uses that to determine the number of planes used by the format.
+ *
+ * \return The number of planes used by the format
+ */
+unsigned int PixelFormatInfo::planeCount() const
+{
+	unsigned int count = 0;
+
+	for (const PixelFormatPlaneInfo &p : planes) {
+		if (p.bytesPerGroup == 0)
+			break;
+
+		count++;
+	}
+
+	return count;
+}
+
 } /* namespace libcamera */
-- 
2.25.1