@@ -13,6 +13,7 @@
#include <linux/videodev2.h>
#include <libcamera/geometry.h>
+#include <libcamera/pixelformats.h>
#include <libcamera/signal.h>
#include "formats.h"
@@ -155,6 +156,10 @@ public:
static V4L2VideoDevice *fromEntityName(const MediaDevice *media,
const std::string &entity);
+ static PixelFormat toPixelFormat(uint32_t v4l2Fourcc);
+ uint32_t toV4L2Fourcc(PixelFormat pixelFormat);
+ static uint32_t toV4L2Fourcc(PixelFormat pixelFormat, bool multiplanar);
+
protected:
std::string logPrefix() const;
@@ -17,6 +17,8 @@
#include <unistd.h>
#include <vector>
+#include <linux/drm_fourcc.h>
+
#include <libcamera/buffer.h>
#include <libcamera/event_notifier.h>
@@ -1234,6 +1236,145 @@ V4L2VideoDevice *V4L2VideoDevice::fromEntityName(const MediaDevice *media,
return new V4L2VideoDevice(mediaEntity);
}
+/**
+ * \brief Convert a \a v4l2Fourcc code to its corresponding PixelFormat
+ * \param[in] v4l2Fourcc A V4L2_PIX_FORMAT_* pixel code
+ * \return The PixelFormat corresponding to \a v4l2Fourcc
+ */
+PixelFormat V4L2VideoDevice::toPixelFormat(uint32_t v4l2Fourcc)
+{
+ switch (v4l2Fourcc) {
+ /* RGB formats. */
+ case V4L2_PIX_FMT_RGB24:
+ return DRM_FORMAT_BGR888;
+ case V4L2_PIX_FMT_BGR24:
+ return DRM_FORMAT_RGB888;
+ case V4L2_PIX_FMT_ARGB32:
+ return DRM_FORMAT_BGRA8888;
+
+ /* YUV packed formats. */
+ case V4L2_PIX_FMT_YUYV:
+ return DRM_FORMAT_YUYV;
+ case V4L2_PIX_FMT_YVYU:
+ return DRM_FORMAT_YVYU;
+ case V4L2_PIX_FMT_UYVY:
+ return DRM_FORMAT_UYVY;
+ case V4L2_PIX_FMT_VYUY:
+ return DRM_FORMAT_VYUY;
+
+ /* YUY planar formats. */
+ case V4L2_PIX_FMT_NV16:
+ case V4L2_PIX_FMT_NV16M:
+ return DRM_FORMAT_NV16;
+ case V4L2_PIX_FMT_NV61:
+ case V4L2_PIX_FMT_NV61M:
+ return DRM_FORMAT_NV61;
+ case V4L2_PIX_FMT_NV12:
+ case V4L2_PIX_FMT_NV12M:
+ return DRM_FORMAT_NV12;
+ case V4L2_PIX_FMT_NV21:
+ case V4L2_PIX_FMT_NV21M:
+ return DRM_FORMAT_NV21;
+
+ /* Compressed formats. */
+ case V4L2_PIX_FMT_MJPEG:
+ return DRM_FORMAT_MJPEG;
+
+ /* V4L2 formats not yet supported by DRM. */
+ case V4L2_PIX_FMT_GREY:
+ default:
+ /*
+ * \todo We can't use LOG() in a static method of a Loggable
+ * class. Until we fix the logger, work around it.
+ */
+ libcamera::_log(__FILE__, __LINE__, _LOG_CATEGORY(V4L2)(),
+ LogError).stream()
+ << "Unsupported V4L2 pixel format "
+ << utils::hex(v4l2Fourcc);
+ return 0;
+ }
+}
+
+/**
+ * \brief Convert \a PixelFormat to its corresponding V4L2 fourcc code
+ * \param[in] pixelFormat The PixelFormat to convert
+ *
+ * For multiplanar formats, the V4L2 format variant (contiguous or
+ * non-contiguous planes) is selected automatically based on the capabilities
+ * of the video device. If the video device supports the V4L2 multiplanar API,
+ * non-contiguous formats are preferred.
+ *
+ * \return The V4L2_PIX_FMT_* pixel format code corresponding to \a pixelFormat
+ */
+uint32_t V4L2VideoDevice::toV4L2Fourcc(PixelFormat pixelFormat)
+{
+ return V4L2VideoDevice::toV4L2Fourcc(pixelFormat, caps_.isMultiplanar());
+}
+
+/**
+ * \brief Convert \a pixelFormat to its corresponding V4L2 fourcc code
+ * \param[in] pixelFormat The PixelFormat to convert
+ * \param[in] multiplanar V4L2 Multiplanar API support flag
+ *
+ * Multiple V4L2 formats may exist for one PixelFormat when the format uses
+ * multiple planes, as V4L2 defines separate 4CCs for contiguous and separate
+ * planes formats. Set the \a multiplanar parameter to false to select a format
+ * with contiguous planes, or to true to select a format with non-contiguous
+ * planes.
+ *
+ * \return The V4L2_PIX_FMT_* pixel format code corresponding to \a pixelFormat
+ */
+uint32_t V4L2VideoDevice::toV4L2Fourcc(PixelFormat pixelFormat, bool multiplanar)
+{
+ switch (pixelFormat) {
+ /* RGB formats. */
+ case DRM_FORMAT_BGR888:
+ return V4L2_PIX_FMT_RGB24;
+ case DRM_FORMAT_RGB888:
+ return V4L2_PIX_FMT_BGR24;
+ case DRM_FORMAT_BGRA8888:
+ return V4L2_PIX_FMT_ARGB32;
+
+ /* YUV packed formats. */
+ case DRM_FORMAT_YUYV:
+ return V4L2_PIX_FMT_YUYV;
+ case DRM_FORMAT_YVYU:
+ return V4L2_PIX_FMT_YVYU;
+ case DRM_FORMAT_UYVY:
+ return V4L2_PIX_FMT_UYVY;
+ case DRM_FORMAT_VYUY:
+ return V4L2_PIX_FMT_VYUY;
+
+ /*
+ * YUY planar formats.
+ * \todo Add support for non-contiguous memory planes
+ * \todo Select the format variant not only based on \a multiplanar but
+ * also take into account the formats supported by the device.
+ */
+ case DRM_FORMAT_NV16:
+ return V4L2_PIX_FMT_NV16;
+ case DRM_FORMAT_NV61:
+ return V4L2_PIX_FMT_NV61;
+ case DRM_FORMAT_NV12:
+ return V4L2_PIX_FMT_NV12;
+ case DRM_FORMAT_NV21:
+ return V4L2_PIX_FMT_NV21;
+
+ /* Compressed formats. */
+ case DRM_FORMAT_MJPEG:
+ return V4L2_PIX_FMT_MJPEG;
+ }
+
+ /*
+ * \todo We can't use LOG() in a static method of a Loggable
+ * class. Until we fix the logger, work around it.
+ */
+ libcamera::_log(__FILE__, __LINE__, _LOG_CATEGORY(V4L2)(), LogError).stream()
+ << "Unsupported V4L2 pixel format "
+ << utils::hex(pixelFormat);
+ return 0;
+}
+
/**
* \class V4L2M2MDevice
* \brief Memory-to-Memory video device
Add support for the newly introduced PixelFormat type in the V4L2VideoDevice class by providing helper operations to translate a PixelFormat to the corresponding V4L2-defined fourcc code and vice versa. More work is needed to properly suppor the V4L2 multi-planar (*M) formats. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> --- src/libcamera/include/v4l2_videodevice.h | 5 + src/libcamera/v4l2_videodevice.cpp | 141 +++++++++++++++++++++++ 2 files changed, 146 insertions(+)