libcamera  v0.3.0
Supporting cameras in Linux since 2019
media_object.h
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1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 /*
3  * Copyright (C) 2018, Google Inc.
4  *
5  * Media Device objects: entities, pads and links.
6  */
7 
8 #pragma once
9 
10 #include <string>
11 #include <vector>
12 
13 #include <linux/media.h>
14 
15 #include <libcamera/base/class.h>
16 
17 namespace libcamera {
18 
19 class MediaDevice;
20 class MediaEntity;
21 class MediaPad;
22 
24 {
25 public:
26  MediaDevice *device() { return dev_; }
27  const MediaDevice *device() const { return dev_; }
28  unsigned int id() const { return id_; }
29 
30 protected:
31  friend class MediaDevice;
32 
33  MediaObject(MediaDevice *dev, unsigned int id)
34  : dev_(dev), id_(id)
35  {
36  }
37  virtual ~MediaObject() = default;
38 
40  unsigned int id_;
41 };
42 
43 class MediaLink : public MediaObject
44 {
45 public:
46  MediaPad *source() const { return source_; }
47  MediaPad *sink() const { return sink_; }
48  unsigned int flags() const { return flags_; }
49  int setEnabled(bool enable);
50 
51 private:
53 
54  friend class MediaDevice;
55 
56  MediaLink(const struct media_v2_link *link,
57  MediaPad *source, MediaPad *sink);
58 
59  MediaPad *source_;
60  MediaPad *sink_;
61  unsigned int flags_;
62 };
63 
64 class MediaPad : public MediaObject
65 {
66 public:
67  unsigned int index() const { return index_; }
68  MediaEntity *entity() const { return entity_; }
69  unsigned int flags() const { return flags_; }
70  const std::vector<MediaLink *> &links() const { return links_; }
71 
72  void addLink(MediaLink *link);
73 
74 private:
76 
77  friend class MediaDevice;
78 
79  MediaPad(const struct media_v2_pad *pad, MediaEntity *entity);
80 
81  unsigned int index_;
82  MediaEntity *entity_;
83  unsigned int flags_;
84 
85  std::vector<MediaLink *> links_;
86 };
87 
88 class MediaEntity : public MediaObject
89 {
90 public:
91  enum class Type {
92  Invalid,
96  };
97 
98  const std::string &name() const { return name_; }
99  unsigned int function() const { return function_; }
100  unsigned int flags() const { return flags_; }
101  Type type() const { return type_; }
102  const std::string &deviceNode() const { return deviceNode_; }
103  unsigned int deviceMajor() const { return major_; }
104  unsigned int deviceMinor() const { return minor_; }
105 
106  const std::vector<MediaPad *> &pads() const { return pads_; }
107  const std::vector<MediaEntity *> ancillaryEntities() const { return ancillaryEntities_; }
108 
109  const MediaPad *getPadByIndex(unsigned int index) const;
110  const MediaPad *getPadById(unsigned int id) const;
111 
112  int setDeviceNode(const std::string &deviceNode);
113 
114 private:
116 
117  friend class MediaDevice;
118 
119  MediaEntity(MediaDevice *dev, const struct media_v2_entity *entity,
120  const struct media_v2_interface *iface);
121 
122  void addPad(MediaPad *pad);
123 
124  void addAncillaryEntity(MediaEntity *ancillaryEntity);
125 
126  std::string name_;
127  unsigned int function_;
128  unsigned int flags_;
129  Type type_;
130  std::string deviceNode_;
131  unsigned int major_;
132  unsigned int minor_;
133 
134  std::vector<MediaPad *> pads_;
135  std::vector<MediaEntity *> ancillaryEntities_;
136 };
137 
138 } /* namespace libcamera */
Utilities to help constructing class interfaces.
unsigned int id_
The media object id.
Definition: media_object.h:40
The MediaDevice represents a Media Controller device with its full graph of connected objects...
Definition: media_device.h:25
const std::vector< MediaPad * > & pads() const
Retrieve all pads of the entity.
Definition: media_object.h:106
const std::vector< MediaLink * > & links() const
Retrieve all links in the pad.
Definition: media_object.h:70
Top-level libcamera namespace.
Definition: backtrace.h:17
unsigned int flags() const
Retrieve the pad flags.
Definition: media_object.h:69
Type type() const
Retrieve the entity&#39;s type.
Definition: media_object.h:101
unsigned int deviceMinor() const
Retrieve the minor number of the interface associated with the entity.
Definition: media_object.h:104
const std::string & deviceNode() const
Retrieve the entity&#39;s device node path, if any.
Definition: media_object.h:102
MediaEntity * entity() const
Retrieve the entity the pad belongs to.
Definition: media_object.h:68
Base class for all media objects.
Definition: media_object.h:23
V4L2VideoDevice object and API.
Definition: v4l2_videodevice.h:187
The MediaEntity represents an entity in the media graph.
Definition: media_object.h:88
Type
The type of the interface exposed by the entity to userspace.
Definition: media_object.h:91
MediaObject(MediaDevice *dev, unsigned int id)
Construct a MediaObject part of the MediaDevice dev, identified by the id unique within the device...
Definition: media_object.h:33
#define LIBCAMERA_DISABLE_COPY_AND_MOVE(klass)
Disable copy and move construction and assignment of the klass.
const MediaDevice * device() const
Retrieve the media device the media object belongs to.
Definition: media_object.h:27
MediaDevice * device()
Retrieve the media device the media object belongs to.
Definition: media_object.h:26
unsigned int flags() const
Retrieve the entity&#39;s flags.
Definition: media_object.h:100
unsigned int deviceMajor() const
Retrieve the major number of the interface associated with the entity.
Definition: media_object.h:103
MediaDevice * dev_
The media device the media object belongs to.
Definition: media_object.h:39
const std::string & name() const
Retrieve the entity name.
Definition: media_object.h:98
unsigned int index() const
Retrieve the pad index.
Definition: media_object.h:67
unsigned int id() const
Retrieve the media object id.
Definition: media_object.h:28
const std::vector< MediaEntity * > ancillaryEntities() const
Retrieve all ancillary entities of the entity.
Definition: media_object.h:107
A V4L2 subdevice as exposed by the Linux kernel.
Definition: v4l2_subdevice.h:73
The MediaPad represents a pad of an entity in the media graph.
Definition: media_object.h:64