https://boofcv.org/index.php?action=history&feed=atom&title=Example_Fiducial_Square_Hamming
Example Fiducial Square Hamming - Revision history
2026-05-14T05:46:08Z
Revision history for this page on the wiki
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https://boofcv.org/index.php?title=Example_Fiducial_Square_Hamming&diff=3137&oldid=prev
Peter at 22:42, 17 January 2022
2022-01-17T22:42:59Z
<p></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 22:42, 17 January 2022</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Example Code:</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Example Code:</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>* [https://github.com/lessthanoptimal/BoofCV/blob/v0.<del style="font-weight: bold; text-decoration: none;">39</del>/examples/src/main/java/boofcv/examples/fiducial/ExampleFiducialHamming.java ExampleFiducialHamming.java]</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>* [https://github.com/lessthanoptimal/BoofCV/blob/v0.<ins style="font-weight: bold; text-decoration: none;">40</ins>/examples/src/main/java/boofcv/examples/fiducial/ExampleFiducialHamming.java ExampleFiducialHamming.java]</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Concepts:</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Concepts:</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l61">Line 61:</td>
<td colspan="2" class="diff-lineno">Line 61:</td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> // Load the image</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> // Load the image</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> BufferedImage buffered = UtilImageIO.<del style="font-weight: bold; text-decoration: none;">loadImage</del>(new File(directory, name).getPath());</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> BufferedImage buffered = UtilImageIO.<ins style="font-weight: bold; text-decoration: none;">loadImageNotNull</ins>(new File(directory, name).getPath());</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> // Convert to a BoofCV format</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> // Convert to a BoofCV format</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l71">Line 71:</td>
<td colspan="2" class="diff-lineno">Line 71:</td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> // Render a 3D compute on top of all detections</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> // Render a 3D compute on top of all detections</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> Graphics2D g2 = buffered.createGraphics();</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> Graphics2D g2 = buffered.createGraphics();</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> <del style="font-weight: bold; text-decoration: none;">Se3_F64 </del>targetToSensor = new Se3_F64();</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> <ins style="font-weight: bold; text-decoration: none;">var </ins>targetToSensor = new Se3_F64();</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> <del style="font-weight: bold; text-decoration: none;">Point2D_F64 </del>locationPixel = new Point2D_F64();</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> <ins style="font-weight: bold; text-decoration: none;">var </ins>locationPixel = new Point2D_F64();</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> <del style="font-weight: bold; text-decoration: none;">Polygon2D_F64 </del>bounds = new Polygon2D_F64();</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> <ins style="font-weight: bold; text-decoration: none;">var </ins>bounds = new Polygon2D_F64();</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> for (int i = 0; i < detector.totalFound(); i++) {</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> for (int i = 0; i < detector.totalFound(); i++) {</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> detector.getCenter(i, locationPixel);</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> detector.getCenter(i, locationPixel);</div></td></tr>
</table>
Peter
https://boofcv.org/index.php?title=Example_Fiducial_Square_Hamming&diff=3017&oldid=prev
Peter at 03:16, 9 October 2021
2021-10-09T03:16:50Z
<p></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<col class="diff-marker" />
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 03:16, 9 October 2021</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div></center></div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div></center></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Demonstration how to detect square fiducials which match targets based on hamming distance, e.g. <del style="font-weight: bold; text-decoration: none;">ArUci </del>and AprilTags.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Demonstration how to detect square fiducials which match targets based on hamming distance, e.g. <ins style="font-weight: bold; text-decoration: none;">ArUco </ins>and AprilTags.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Example Code:</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Example Code:</div></td></tr>
</table>
Peter
https://boofcv.org/index.php?title=Example_Fiducial_Square_Hamming&diff=3014&oldid=prev
Peter: Created page with "<center> <gallery widths=500px heights=300px> file:Example_fiducial_square_hamming.jpg | Rendered 3D flat squares on top of fiducials. ArUco MIP 25h7 markers. </gallery> </cen..."
2021-10-09T03:14:31Z
<p>Created page with "<center> <gallery widths=500px heights=300px> file:Example_fiducial_square_hamming.jpg | Rendered 3D flat squares on top of fiducials. ArUco MIP 25h7 markers. </gallery> </cen..."</p>
<p><b>New page</b></p><div><center><br />
<gallery widths=500px heights=300px><br />
file:Example_fiducial_square_hamming.jpg | Rendered 3D flat squares on top of fiducials. ArUco MIP 25h7 markers.<br />
</gallery><br />
</center><br />
<br />
Demonstration how to detect square fiducials which match targets based on hamming distance, e.g. ArUci and AprilTags.<br />
<br />
Example Code:<br />
* [https://github.com/lessthanoptimal/BoofCV/blob/v0.39/examples/src/main/java/boofcv/examples/fiducial/ExampleFiducialHamming.java ExampleFiducialHamming.java]<br />
<br />
Concepts:<br />
* Fiducials<br />
* Pose estimation<br />
<br />
Relevant Examples/Tutorials:<br />
* [[Tutorial_Fiducials|Tutorial Fiducials]]<br />
* [[Example_Fiducial_Square_Image|Example Fiducial Square Image]]<br />
* [[Example_Fiducial_Square_Binary|Example Fiducial Square Binary]]<br />
* [[Example_Calibration_Target_Pose|Example Fiducial Calibration Target]]<br />
<br />
Videos<br />
* [https://youtu.be/qJWDK_FrgHE Fiducial Overview]<br />
<br />
= Example Code =<br />
<br />
<syntaxhighlight lang="java"><br />
/**<br />
* Hamming fiducials are an entire family of markers/tags which work by identifying unique ID's by minimizing<br />
* the hamming distance. This family includes ArUco, ArUco 3, AprilTag, and others. Several prebuilt dictionaries<br />
* are included with BoofCV and you can specify your own easily. Hamming tags have error correction capabilities<br />
* can are resiliant to noise. How resilient depends on the dictionary. In general the fewer unique IDs available<br />
* the better it is at error correction. The recommended dictionary is ARUCO_MIP_25h7.<br />
*<br />
* See:<br />
* Aruco https://www.uco.es/investiga/grupos/ava/node/26<br />
* AprilTag https://april.eecs.umich.edu/software/apriltag<br />
*<br />
* @author Peter Abeles<br />
*/<br />
public class ExampleFiducialHamming {<br />
public static void main( String[] args ) {<br />
String directory = UtilIO.pathExample("fiducial/square_hamming/aruco_25h7");<br />
<br />
// load the lens distortion parameters and the input image<br />
CameraPinholeBrown param = CalibrationIO.load(new File(directory, "intrinsic.yaml"));<br />
LensDistortionNarrowFOV lensDistortion = new LensDistortionBrown(param);<br />
<br />
// You need to create a different configuration for each dictionary type<br />
ConfigHammingMarker configMarker = ConfigHammingMarker.loadDictionary(HammingDictionary.ARUCO_MIP_25h7);<br />
FiducialDetector<GrayF32> detector = FactoryFiducial.squareHamming(configMarker, /*detector*/null, GrayF32.class);<br />
<br />
// Provide it lens parameters so that a 3D pose estimate is possible<br />
detector.setLensDistortion(lensDistortion, param.width, param.height);<br />
<br />
// Load and process all example images<br />
ListDisplayPanel gui = new ListDisplayPanel();<br />
for (int imageID = 1; imageID <= 3; imageID++) {<br />
String name = String.format("image%02d.jpg", imageID);<br />
System.out.println("processing: " + name);<br />
<br />
// Load the image<br />
BufferedImage buffered = UtilImageIO.loadImage(new File(directory, name).getPath());<br />
<br />
// Convert to a BoofCV format<br />
GrayF32 input = ConvertBufferedImage.convertFrom(buffered, (GrayF32)null);<br />
<br />
// Run the detector<br />
detector.detect(input);<br />
<br />
// Render a 3D compute on top of all detections<br />
Graphics2D g2 = buffered.createGraphics();<br />
Se3_F64 targetToSensor = new Se3_F64();<br />
Point2D_F64 locationPixel = new Point2D_F64();<br />
Polygon2D_F64 bounds = new Polygon2D_F64();<br />
for (int i = 0; i < detector.totalFound(); i++) {<br />
detector.getCenter(i, locationPixel);<br />
detector.getBounds(i, bounds);<br />
<br />
g2.setColor(new Color(50, 50, 255));<br />
g2.setStroke(new BasicStroke(10));<br />
VisualizeShapes.drawPolygon(bounds, true, 1.0, g2);<br />
<br />
if (detector.hasID())<br />
System.out.println("Target ID = " + detector.getId(i));<br />
if (detector.hasMessage())<br />
System.out.println("Message = " + detector.getMessage(i));<br />
System.out.println("2D Image Location = " + locationPixel);<br />
<br />
if (detector.is3D()) {<br />
detector.getFiducialToCamera(i, targetToSensor);<br />
System.out.println("3D Location:");<br />
System.out.println(targetToSensor);<br />
VisualizeFiducial.drawCube(targetToSensor, param, detector.getWidth(i), 3, g2);<br />
VisualizeFiducial.drawLabelCenter(targetToSensor, param, "" + detector.getId(i), g2);<br />
} else {<br />
VisualizeFiducial.drawLabel(locationPixel, "" + detector.getId(i), g2);<br />
}<br />
}<br />
gui.addImage(buffered, name, ScaleOptions.ALL);<br />
}<br />
ShowImages.showWindow(gui, "Example Fiducial Hamming", true);<br />
}<br />
}<br />
</syntaxhighlight></div>
Peter