@@ -8,6 +8,7 @@
#define __LIBCAMERA_STREAM_H__
#include <libcamera/buffer.h>
+#include <libcamera/geometry.h>
namespace libcamera {
@@ -21,9 +22,48 @@ struct StreamConfiguration {
unsigned int bufferCount;
};
+class StreamUsage
+{
+public:
+ enum Role {
+ StillCapture,
+ VideoRecording,
+ Viewfinder,
+ };
+
+ Role role() const { return role_; }
+ const Size &size() const { return size_; }
+
+protected:
+ explicit StreamUsage(Role role);
+ StreamUsage(Role role, int width, int height);
+
+private:
+ Role role_;
+ Size size_;
+};
+
class Stream final
{
public:
+ class StillCapture : public StreamUsage
+ {
+ public:
+ StillCapture();
+ };
+
+ class VideoRecording : public StreamUsage
+ {
+ public:
+ VideoRecording();
+ };
+
+ class Viewfinder : public StreamUsage
+ {
+ public:
+ Viewfinder(int width, int height);
+ };
+
Stream();
BufferPool &bufferPool() { return bufferPool_; }
const StreamConfiguration &configuration() const { return configuration_; }
@@ -60,6 +60,65 @@ namespace libcamera {
* \brief Requested number of buffers to allocate for the stream
*/
+/**
+ * \class StreamUsage
+ * \brief Stream usage information
+ *
+ * The StreamUsage class describes how an application intends to use a stream.
+ * Usages are specified by applications and passed to cameras, that then select
+ * the most appropriate streams and their default configurations.
+ */
+
+/**
+ * \enum StreamUsage::Role
+ * \brief Identify the role a stream is intended to play
+ * \var StreamUsage::StillCapture
+ * The stream is intended to capture high-resolution, high-quality still images
+ * with low frame rate. The captured frames may be exposed with flash.
+ * \var StreamUsage::VideoRecording
+ * The stream is intended to capture video for the purpose of recording or
+ * streaming. The video stream may produce a high frame rate and may be
+ * enhanced with video stabilization.
+ * \var StreamUsage::Viewfinder
+ * The stream is intended to capture video for the purpose of display on the
+ * local screen. The StreamUsage includes the desired resolution. Trade-offs
+ * between quality and usage of system resources are acceptable.
+ */
+
+/**
+ * \fn StreamUsage::role()
+ * \brief Retrieve the stream role
+ *
+ * \return The stream role
+ */
+
+/**
+ * \fn StreamUsage::size()
+ * \brief Retrieve desired size
+ *
+ * \return The desired size
+ */
+
+/**
+ * \brief Create a stream usage
+ * \param[in] role Stream role
+ */
+StreamUsage::StreamUsage(Role role)
+ : role_(role)
+{
+}
+
+/**
+ * \brief Create a stream usage with a desired size
+ * \param[in] role Stream role
+ * \param[in] width The desired width
+ * \param[in] height The desired height
+ */
+StreamUsage::StreamUsage(Role role, int width, int height)
+ : role_(role), size_(Size(width, height))
+{
+}
+
/**
* \class Stream
* \brief Video stream for a camera
@@ -78,6 +137,39 @@ namespace libcamera {
* optimal stream for the task.
*/
+/**
+ * \class Stream::StillCapture
+ * \brief Describe a still capture usage
+ */
+Stream::StillCapture::StillCapture()
+ : StreamUsage(Role::StillCapture)
+{
+}
+
+/**
+ * \class Stream::VideoRecording
+ * \brief Describe a video recording usage
+ */
+Stream::VideoRecording::VideoRecording()
+ : StreamUsage(Role::VideoRecording)
+{
+}
+
+/**
+ * \class Stream::Viewfinder
+ * \brief Describe a viewfinder usage
+ */
+
+/**
+ * \brief Create a viewfinder usage with a desired dimension
+ * \param[in] width The desired viewfinder width
+ * \param[in] height The desired viewfinder height
+ */
+Stream::Viewfinder::Viewfinder(int width, int height)
+ : StreamUsage(Role::Viewfinder, width, height)
+{
+}
+
/**
* \brief Construct a stream with default parameters
*/