[libcamera-devel,RFC,2/4] libcamera: stream: add basic stream class

318 diff mbox series

diff --git a/include/libcamera/libcamera.h b/include/libcamera/libcamera.h
index c0511cf6d662b63f..272dfd5e4a67d5de 100644
--- a/include/libcamera/libcamera.h
+++ b/include/libcamera/libcamera.h
@@ -12,6 +12,7 @@ 
 #include <libcamera/event_dispatcher.h>
 #include <libcamera/event_notifier.h>
 #include <libcamera/signal.h>
+#include <libcamera/stream.h>
 #include <libcamera/timer.h>
 
 #endif /* __LIBCAMERA_LIBCAMERA_H__ */
diff --git a/include/libcamera/meson.build b/include/libcamera/meson.build
index d7cb55ba4a49e1e8..54a680787e5c17aa 100644
--- a/include/libcamera/meson.build
+++ b/include/libcamera/meson.build
@@ -5,6 +5,7 @@  libcamera_api = files([
     'event_notifier.h',
     'libcamera.h',
     'signal.h',
+    'stream.h',
     'timer.h',
 ])
 
diff --git a/include/libcamera/stream.h b/include/libcamera/stream.h
new file mode 100644
index 0000000000000000..8386c68e33fe57d0
--- /dev/null
+++ b/include/libcamera/stream.h
@@ -0,0 +1,25 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * stream.h - Stream object interface
+ */
+#ifndef __LIBCAMERA_STREAM_H__
+#define __LIBCAMERA_STREAM_H__
+
+namespace libcamera {
+
+class Stream final
+{
+public:
+	Stream(unsigned int id);
+
+	unsigned int id() { return id_; };
+
+private:
+	unsigned int id_;
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_STREAM_H__ */
diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build
index f9f25c0ecf1564cc..9f6ff99eebe2f5bc 100644
--- a/src/libcamera/meson.build
+++ b/src/libcamera/meson.build
@@ -10,6 +10,7 @@  libcamera_sources = files([
     'media_object.cpp',
     'pipeline_handler.cpp',
     'signal.cpp',
+    'stream.cpp',
     'timer.cpp',
     'v4l2_device.cpp',
 ])
diff --git a/src/libcamera/stream.cpp b/src/libcamera/stream.cpp
new file mode 100644
index 0000000000000000..db47c24760b360b4
--- /dev/null
+++ b/src/libcamera/stream.cpp
@@ -0,0 +1,58 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * stream.cpp - Stream information
+ */
+
+#include <libcamera/stream.h>
+
+/**
+ * \file stream.h
+ * \brief Stream information handling
+ *
+ * Each camera device is composed of one or multiple video stream connected
+ * to one image source. The Stream class holds all static information about
+ * a stream belonging to a camera device. A camera should provide a separate
+ * Stream object for every stream it can support.
+ *
+ * Camera devices expose at least one stream, and may expose additional streams
+ * based on the device capabilities. This can be used, for instance, to
+ * implement concurrent viewfinder and video capture, or concurrent viewfinder,
+ * video capture and still image capture.
+ */
+
+namespace libcamera {
+
+/**
+ * \class Stream
+ * \brief Stream information carrier
+ *
+ * The Stream class is a model of all static information which can be
+ * associated with a video stream. It provides the mapping of a stream
+ * capabilities to a numerical ID which should be used when configuring
+ * the camera which might contain a collections of streams.
+ *
+ * \todo Add capabilities to the Stream API. Without this the Stream class
+ *	 only serves to map streams of unknown capabilities to a stream ID.
+ *	 This in it self is important as it allows applications to configure
+ *	 and capture from one or more streams even if it won't be able to
+ *	 select the optimal stream for the task.
+ */
+
+/**
+ * \brief Create a new stream with a ID
+ * \param[in] id Numerical ID which should be unique for the camera device the stream belongs to.
+ */
+Stream::Stream(unsigned int id)
+	: id_(id)
+{
+}
+
+/**
+ * \fn Stream::id()
+ * \brief Retrieve the streams ID
+ * \return The stream ID
+ */
+
+} /* namespace libcamera */