[libcamera-devel,v6,1/6] libcamera: stream: add initial Stream class

454 diff mbox series

diff --git a/include/libcamera/libcamera.h b/include/libcamera/libcamera.h
index 6619e556ebbd20e4..8167e8099ac061d2 100644
--- a/include/libcamera/libcamera.h
+++ b/include/libcamera/libcamera.h
@@ -13,6 +13,7 @@ 
 #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 8fcbbf7892ea9280..8c14423bc444ef51 100644
--- a/include/libcamera/meson.build
+++ b/include/libcamera/meson.build
@@ -6,6 +6,7 @@  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..4f47d85ed6382b36
--- /dev/null
+++ b/include/libcamera/stream.h
@@ -0,0 +1,18 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * stream.h - Video stream for a Camera
+ */
+#ifndef __LIBCAMERA_STREAM_H__
+#define __LIBCAMERA_STREAM_H__
+
+namespace libcamera {
+
+class Stream final
+{
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_STREAM_H__ */
diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build
index b5b25965fd123350..a4e9cc8f936c47a7 100644
--- a/src/libcamera/meson.build
+++ b/src/libcamera/meson.build
@@ -11,6 +11,7 @@  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..9417c5886185d35c
--- /dev/null
+++ b/src/libcamera/stream.cpp
@@ -0,0 +1,50 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * stream.cpp - Video stream for a Camera
+ */
+
+#include <libcamera/stream.h>
+
+/**
+ * \file stream.h
+ * \brief Video stream for a Camera
+ *
+ * A camera device can provide frames in different resolutions and formats
+ * concurrently from a single image source. The Stream class represents
+ * one of the multiple concurrent streams.
+ *
+ * All streams exposed by a camera device share the same image source and are
+ * thus not fully independent. Parameters related to the image source, such as
+ * the exposure time or flash control, are common to all streams. Other
+ * parameters, such as format or resolution, may be specified per-stream,
+ * depending on the capabilities of the camera device.
+ *
+ * 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 Video stream for a camera
+ *
+ * The Stream class models all static information which are associated with a
+ * single video stream. Streams are exposed by the Camera object they belong to.
+ *
+ * Cameras may supply more than one stream from the same video source. In such
+ * cases an application can inspect all available streams and select the ones
+ * that best fit its use case.
+ *
+ * \todo Add capabilities to the stream API. Without this the Stream class only
+ * serves to reveal how many streams of unknown capabilities a camera supports.
+ * This in itself is productive as it allows applications to configure and
+ * capture from one or more streams even if they won't be able to select the
+ * optimal stream for the task.
+ */
+
+} /* namespace libcamera */