aboutsummaryrefslogtreecommitdiff
path: root/docs/user_guide/aruco_markers_pipeline/aoi_projection.md
blob: 027f805d895cc303dab773f80b78a6f000e1494a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
Project AOI into camera frame
=============================

Once [ArUcoScene pose is estimated](pose_estimation.md) and [AOI are described](aoi_description.md), AOI can be projected into [ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) frame.

![AOI projection](../../img/aruco_camera_aoi_projection.png)

## Add ArLayer to ArUcoScene to load AOI

The [ArLayer](../../argaze.md/#argaze.ArFeatures.ArLayer) class allows to load areas of interest description. An [ArUcoScene](../../argaze.md/#argaze.ArUcoMarkers.ArUcoScene) instance can contains multiples [ArLayers](../../argaze.md/#argaze.ArFeatures.ArLayer).

Here is the previous extract where one layer is added to the [ArUcoScene](../../argaze.md/#argaze.ArUcoMarkers.ArUcoScene) configuration:

```json
{
    "name": "My FullHD camera",
    "size": [1920, 1080],
    ...
    "scenes": {
        "MyScene" : {
            "aruco_markers_group": {
                ...
            },
            "layers": {
                "MyLayer": {
                    "aoi_scene": {
                        "YellowSquare": [[6.2, -7.275252, 25.246159], [31.2, -7.275252, 25.246159], [31.2, 1.275252, 1.753843], [6.2, 1.275252, 1.753843]],
                        "GrayRectangle": [[2.5, 2.5, -0.5], [37.5, 2.5, -0.5], [37.5, 27.5, -0.5], [2.5, 27.5, -0.5]],
                        "BlueTriangle": [[12.5, 7.5, -0.5], [27.5, 7.5, -0.5], [20, 22.5, -0.5]]
                    }
                }
            } 
        }
    }
    ...
}
```

Now, let's understand the meaning of each JSON entry.

### "MyLayer"

The name of the [ArLayer](../../argaze.md/#argaze.ArFeatures.ArLayer). Basically useful for visualisation purpose.

### AOI Scene

The [AOIScene](../../argaze.md/#argaze.AreaOfInterest.AOIFeatures.AOIScene) defines a set of 3D [AreaOfInterest](../../argaze.md/#argaze.AreaOfInterest.AOIFeatures.AreaOfInterest) registered by name.

## Add ArLayer to ArUcoCamera to project AOI

Here is the previous extract where one layer is added to the [ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) and displayed:

```json
{
    "name": "My FullHD camera",
    "size": [1920, 1080],
    ...
    "scenes": {
        "MyScene" : {
            "aruco_markers_group": {
                ...
            },
            "layers": {
                 "MyLayer": {
                    "aoi_scene": {
                        ...
                    }
                } 
            } 
        }
    },
    "layers": {
        "MyLayer": {}
    }
    ...
    "image_parameters": {
        ...
        "draw_layers": {
            "MyLayer": {
                "draw_aoi_scene": {
                    "draw_aoi": {
                        "color": [255, 255, 255],
                        "border_size": 1
                    }
                }
            }
        }
    }
}
```

Now, let's understand the meaning of each JSON entry.

### "MyLayer"

The name of the [ArLayer](../../argaze.md/#argaze.ArFeatures.ArLayer). Basically useful for visualisation purpose.

!!! warning "Layer name policy"

    An [ArUcoScene](../../argaze.md/#argaze.ArUcoMarkers.ArUcoScene) layer is projected into [an ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) layer, **provided they have the same name**.

!!! note

    [ArUcoScene](../../argaze.md/#argaze.ArUcoMarkers.ArUcoScene) layers are projected into their dedicated [ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) layers when calling the [ArUcoCamera.watch](../../argaze.md/#argaze.ArFeatures.ArCamera.watch) method.

## Add AOI analysis

When a scene layer is projected into a camera layer, it means that the 3D [ArLayer.aoi_scene](../../argaze.md/#argaze.ArFeatures.ArLayer.aoi_scene) description of the scene becomes the 2D camera's [ArLayer.aoi_scene](../../argaze.md/#argaze.ArFeatures.ArLayer.aoi_scene) description of the camera.

Therefore, it means that [ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) benefits from all the services described in [AOI analysis pipeline section](../gaze_analysis_pipeline/aoi_analysis.md).

Here is the previous extract where AOI matcher, AOI scan path and AOI scan path analyzers are added to the [ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) layer:

```json
{
    "name": "My FullHD camera",
    "size": [1920, 1080],
    ...
    "scenes": {
        "MyScene" : {
            "aruco_markers_group": {
                ...
            },
            "layers": {
                 "MyLayer": {
                    "aoi_scene": {
                        ...
                    }
                } 
            } 
        }
    },
    "layers": {
        "MyLayer": {
            "aoi_matcher": {
                "DeviationCircleCoverage": {
                    "coverage_threshold": 0.5
                }
            },
            "aoi_scan_path": {
                "duration_max": 30000
            },
            "aoi_scan_path_analyzers": {
                "Basic": {},
                "TransitionMatrix": {},
                "NGram": {
                    "n_min": 3,
                    "n_max": 5
                }
            }
        }
    }
    ...
}
```

!!! warning

    Adding scan path and scan path analyzers to an [ArUcoCamera](../../argaze.md/#argaze.ArUcoMarkers.ArUcoCamera) layer doesn't make sense if the camera is moving.