Animate images with image overlay

View inQMLC++
View on GitHub
Sample viewer app

Animate a series of images with an image overlay.

screenshot

Use case

An image overlay is useful for displaying fast and dynamic images; for example, rendering real-time sensor data captured from a drone. Each frame from the drone becomes a static image which is updated on the fly as the data is made available.

How to use the sample

The application loads a map of the Southwestern United States. Click the "Start" or "Stop" buttons to start or stop the radar animation. Use the drop down menu to select how quickly the animation plays. Move the slider to change the opacity of the image overlay.

How it works

  1. Create an ImageOverlay and add it to the SceneView.
  2. Set up a timer with an initial interval time of 68ms, which will display approximately 15 ImageFrames per second.
  3. Connect to the timeout signal from the timer.
  4. Create a new image frame every timeout and set it on the image overlay.

Relevant API

  • ImageFrame
  • ImageOverlay
  • SceneView

Offline data

Link Local Location
Pacific South West Images <userhome>/ArcGIS/Runtime/Data/3D/ImageOverlay/PacificSouthWest.zip

About the data

These radar images were captured by the US National Weather Service (NWS). They highlight the Pacific Southwest sector which is made up of part the western United States and Mexico. For more information visit the National Weather Service website.

Additional information

The supported image formats are GeoTIFF, TIFF, JPEG, and PNG. ImageOverlay does not support the rich processing and rendering capabilities of a RasterLayer. Use Raster and RasterLayer for static image rendering, analysis, and persistence.

Tags

3d, animation, drone, dynamic, image frame, image overlay, real time, rendering

Sample Code

AnimateImagesWithImageOverlay.cppAnimateImagesWithImageOverlay.cppAnimateImagesWithImageOverlay.hAnimateImagesWithImageOverlay.qml
Use dark colors for code blocksCopy
                                                                                                                                                                                                            
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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
// [WriteFile Name=AnimateImagesWithImageOverlay, Category=Scenes]
// [Legal]
// Copyright 2020 Esri.

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// [Legal]

#ifdef PCH_BUILD
#include "pch.hpp"
#endif // PCH_BUILD

#include "AnimateImagesWithImageOverlay.h"

#include "ArcGISTiledElevationSource.h"
#include "ArcGISTiledLayer.h"
#include "Scene.h"
#include "SceneQuickView.h"
#include "ImageFrame.h"
#include "ImageOverlay.h"
#include "ImageOverlayListModel.h"
#include "SceneView.h"
#include "Envelope.h"
#include "Point.h"
#include "Camera.h"
#include "Viewpoint.h"

// Qt headers
#include <QString>
#include <QFile>
#include <QtCore/qglobal.h>
#include <QTimer>

#include <memory>

#ifdef Q_OS_IOS
#include <QStandardPaths>
#endif // Q_OS_IOS

using namespace Esri::ArcGISRuntime;

// helper method to get cross platform data path
namespace
{
QString defaultDataPath()
{
  QString dataPath;

#ifdef Q_OS_ANDROID
  dataPath = "/sdcard";
#elif defined Q_OS_IOS
  dataPath = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
#else
  dataPath = QDir::homePath();
#endif

  return dataPath;
}
} // namespace

using namespace Esri::ArcGISRuntime;

AnimateImagesWithImageOverlay::AnimateImagesWithImageOverlay(QObject* parent /* = nullptr */):
  QObject(parent),
  m_scene(new Scene(this)),
  m_dataPath(defaultDataPath() + "/ArcGIS/Runtime/Data/3D/ImageOverlay/PacificSouthWest"),
  m_dir(m_dataPath),
  m_images(m_dir.entryList(QStringList() << "*.png", QDir::Files)),
  m_imagesSize(m_images.size())
{
  // create a new elevation source from Terrain3D REST service
  ArcGISTiledElevationSource* elevationSource = new ArcGISTiledElevationSource(
        QUrl("https://elevation3d.arcgis.com/arcgis/rest/services/WorldElevation3D/Terrain3D/ImageServer"), this);

  // create a new tiled layer from World_Dark_Gray_Base REST service
  ArcGISTiledLayer* worldDarkGrayBasemap = new ArcGISTiledLayer(QUrl("https://services.arcgisonline.com/arcgis/rest/services/Canvas/World_Dark_Gray_Base/MapServer"), this);

  // add the elevation source to the scene to display elevation
  m_scene->baseSurface()->elevationSources()->append(elevationSource);

  // add the tiled layer to the operational layers to display the basemap
  m_scene->operationalLayers()->append(worldDarkGrayBasemap);
}

AnimateImagesWithImageOverlay::~AnimateImagesWithImageOverlay() = default;

void AnimateImagesWithImageOverlay::init()
{
  // Register classes for QML
  qmlRegisterType<SceneQuickView>("Esri.Samples", 1, 0, "SceneView");
  qmlRegisterType<AnimateImagesWithImageOverlay>("Esri.Samples", 1, 0, "AnimateImagesWithImageOverlaySample");
}

SceneQuickView* AnimateImagesWithImageOverlay::sceneView() const
{
  return m_sceneView;
}

// Set the view (created in QML)
void AnimateImagesWithImageOverlay::setSceneView(SceneQuickView* sceneView)
{
  if (!sceneView || sceneView == m_sceneView)
    return;

  m_sceneView = sceneView;
  m_sceneView->setArcGISScene(m_scene);

  emit sceneViewChanged();

  setupImageOverlay();
}

void AnimateImagesWithImageOverlay::setupImageOverlay()
{
  // create an envelope of the pacific southwest sector for displaying the image frame
  const Point pointForImageFrame(-120.0724273439448, 35.131016955536694, SpatialReference(4326));
  m_pacificSouthwestEnvelope = Envelope(pointForImageFrame, 15.09589635986124, -14.3770441522488);

  // create a camera, looking at the pacific southwest sector
  const Point observationPoint(-116.621, 24.7773, 856977);
  const Camera camera(observationPoint, 353.994, 48.5495, 0);
  const Viewpoint pacificSouthwestViewpoint(observationPoint, camera);

  m_scene->setInitialViewpoint(pacificSouthwestViewpoint);

  // create an image overlay
  m_imageOverlay = new ImageOverlay(this);

  // append the image overlay to the scene view
  m_sceneView->imageOverlays()->append(m_imageOverlay);

  // Create new Timer and set the timeout interval to 68ms
  m_timer = new QTimer(this);
  m_timer->setInterval(68);

  // connect to the timeout signal to load and display a new image frame each time
  connect(m_timer, &QTimer::timeout, this, &AnimateImagesWithImageOverlay::animateImageFrames);
}

void AnimateImagesWithImageOverlay::animateImageFrames()
{
  // check if string list of images is empty before trying to load and animate them
  if (m_imagesSize == 0)
    return;

  // create an image with the given path and use it to create an image frame
  const QImage image(m_dataPath + "/" + m_images[m_index]);

  // use std::unqiue_ptr to handle the lifetime of the image frame
  std::unique_ptr<ImageFrame> imageFrame = std::make_unique<ImageFrame>(image, m_pacificSouthwestEnvelope);

  // set image frame to image overlay
  m_imageOverlay->setImageFrame(imageFrame.get());

  // increment the index to keep track of which image to load next
  m_index++;

  // reset index once all files have been loaded
  if (m_index == m_imagesSize)
    m_index = 0;
}

void AnimateImagesWithImageOverlay::setTimerInterval(int value)
{
  if (!m_timer)
    return;

  m_timer->setInterval(value);
}
void AnimateImagesWithImageOverlay::setOpacity(float value)
{
  if (!m_imageOverlay)
    return;

  m_imageOverlay->setOpacity(value);
}

void AnimateImagesWithImageOverlay::startTimer()
{
  if (!m_timer)
    return;

  m_isStopped = false;
  emit isStoppedChanged();
  m_timer->start();
}

void AnimateImagesWithImageOverlay::stopTimer()
{
  if (!m_timer)
    return;

  m_isStopped = true;
  emit isStoppedChanged();
  m_timer->stop();
}

Your browser is no longer supported. Please upgrade your browser for the best experience. See our browser deprecation post for more details.