[libcamera-devel] [PATCH v3] libcamera: Fix V4L2 pixel format mapping for XRGB32 and RGBX32

[Vedant Paranjape]

On running libcamera gstreamer element on Raspberry Pi 4B+, there was a
warning as follows:

[3:23:59.717513107] [3577] WARN V4L2 v4l2_pixelformat.cpp:180 Unsupported V4L2 pixel format XB24

This patch fixes the following warning, by adding BGRX8888 pixel format
in libcamera, and updating the existing mapping of V4L2_PIX_FMT_XRGB32
to it's corresponding libcamera pixel format. Additionally, adds a new
mapping of V4L2_PIX_FMT_RBGX32 to formats::XBGR8888

Signed-off-by: Vedant Paranjape <vedantparanjape160201 at gmail.com>
---
 src/libcamera/formats.cpp          | 12 +++++++++++-
 src/libcamera/v4l2_pixelformat.cpp |  3 ++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/libcamera/formats.cpp b/src/libcamera/formats.cpp
index 55822f4c..e41bfc05 100644
--- a/src/libcamera/formats.cpp
+++ b/src/libcamera/formats.cpp
@@ -198,13 +198,23 @@ const std::map<PixelFormat, PixelFormatInfo> pixelFormatInfo{
 	{ formats::XBGR8888, {
 		.name = "XBGR8888",
 		.format = formats::XBGR8888,
-		.v4l2Format = V4L2PixelFormat(V4L2_PIX_FMT_XRGB32),
+		.v4l2Format = V4L2PixelFormat(V4L2_PIX_FMT_RGBX32),
 		.bitsPerPixel = 32,
 		.colourEncoding = PixelFormatInfo::ColourEncodingRGB,
 		.packed = false,
 		.pixelsPerGroup = 1,
 		.planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }},
 	} },
+	{ formats::BGRX8888, {
+		.name = "BGRX8888",
+		.format = formats::BGRX8888,
+		.v4l2Format = V4L2PixelFormat(V4L2_PIX_FMT_XRGB32),
+		.bitsPerPixel = 32,
+		.colourEncoding = PixelFormatInfo::ColourEncodingRGB,
+		.packed = false,
+		.pixelsPerGroup = 1,
+		.planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }},
+	} },	
 	{ formats::ABGR8888, {
 		.name = "ABGR8888",
 		.format = formats::ABGR8888,
diff --git a/src/libcamera/v4l2_pixelformat.cpp b/src/libcamera/v4l2_pixelformat.cpp
index 166d93cf..78a08303 100644
--- a/src/libcamera/v4l2_pixelformat.cpp
+++ b/src/libcamera/v4l2_pixelformat.cpp
@@ -51,7 +51,8 @@ const std::map<V4L2PixelFormat, PixelFormat> vpf2pf{
 	{ V4L2PixelFormat(V4L2_PIX_FMT_RGB24), formats::BGR888 },
 	{ V4L2PixelFormat(V4L2_PIX_FMT_BGR24), formats::RGB888 },
 	{ V4L2PixelFormat(V4L2_PIX_FMT_XBGR32), formats::XRGB8888 },
-	{ V4L2PixelFormat(V4L2_PIX_FMT_XRGB32), formats::XBGR8888 },
+	{ V4L2PixelFormat(V4L2_PIX_FMT_XRGB32), formats::BGRX8888 },
+	{ V4L2PixelFormat(V4L2_PIX_FMT_RGBX32), formats::XBGR8888 },
 	{ V4L2PixelFormat(V4L2_PIX_FMT_RGBA32), formats::ABGR8888 },
 	{ V4L2PixelFormat(V4L2_PIX_FMT_ABGR32), formats::ARGB8888 },
 	{ V4L2PixelFormat(V4L2_PIX_FMT_ARGB32), formats::BGRA8888 },
-- 
2.25.1