delete outdated apps

topics/02_passive/index.md

@@ -39,6 +39,17 @@ However, it's essential to note that photogrammetry lacks inherent scale. Withou
 
 <p><img src="images/stereo_plotter.jpg" alt="StereoPlotter"></p>
 
+*Intrinsics and extrinsics parameters*
+Intrinsic parameters describe the properties of a camera's lens and sensor
+Extrinsic parameters describe the camera's position and orientation in 3D space
+
+<p>Groundwork camera properties and standards for USGS photgrammetry surveys.</p>
+<a href="https://www.sciencedirect.com/science/article/abs/pii/0031866373900069">Welch 1973</a>
+
+
+[Levenberg–Marquardt algorithm](https://en.wikipedia.org/wiki/Levenberg%E2%80%93Marquardt_algorithm) or damped least-squares algorithm (dls) are used to minimize the error across 3d coordinates. This procedure is typically called [bundle adjustment](https://en.wikipedia.org/wiki/Bundle_adjustment).
+
+
 While the analog versions of these techniques have waned in popularity, stereophotogrammetry still has applications for capturing dynamic characteristics of previously difficult to measure systems like running <a href="https://www.spiedigitallibrary.org/conference-proceedings-of-spie/8348/1/Dynamic-characteristics-of-a-wind-turbine-blade-using-3D-digital/10.1117/12.915377.short?SSO=1">wind turbines</a>.</p>
 
 When is it useful?
@@ -47,9 +58,6 @@ Photogrammetry is useful for outdoors settings, where all you need is a handheld
 <div class="sketchfab-embed-wrapper"> <iframe title="Arc de Triomphe - photogrammetry" frameborder="0" allowfullscreen="" mozallowfullscreen="true" webkitallowfullscreen="true" allow="fullscreen; autoplay; vr" xr-spatial-tracking="" execution-while-out-of-viewport="" execution-while-not-rendered="" web-share="" src="https://sketchfab.com/models/65937fd27de647c0a8ac99ce8275c03e/embed"> </iframe> <p style="font-size: 13px; font-weight: normal; margin: 5px; color: #4A4A4A;"> <a href="https://sketchfab.com/3d-models/arc-de-triomphe-photogrammetry-65937fd27de647c0a8ac99ce8275c03e?utm_medium=embed&amp;utm_campaign=share-popup&amp;utm_content=65937fd27de647c0a8ac99ce8275c03e" target="_blank" style="font-weight: bold; color: #1CAAD9;"> Arc de Triomphe - photogrammetry </a> by <a href="https://sketchfab.com/nicolasdiolez?utm_medium=embed&amp;utm_campaign=share-popup&amp;utm_content=65937fd27de647c0a8ac99ce8275c03e" target="_blank" style="font-weight: bold; color: #1CAAD9;"> Nicolas Diolez </a> on <a href="https://sketchfab.com?utm_medium=embed&amp;utm_campaign=share-popup&amp;utm_content=65937fd27de647c0a8ac99ce8275c03e" target="_blank" style="font-weight: bold; color: #1CAAD9;">Sketchfab</a></p></div>
 
 
-[Levenberg–Marquardt algorithm](https://en.wikipedia.org/wiki/Levenberg%E2%80%93Marquardt_algorithm) or damped least-squares algorithm (dls) are used to minimize the error across 3d coordinates. This procedure is typically called [bundle adjustment](https://en.wikipedia.org/wiki/Bundle_adjustment).
-<p>Groundwork camera properties and standards for USGS photgrammetry surveys.</p>
-<a href="https://www.sciencedirect.com/science/article/abs/pii/0031866373900069">Welch 1973</a>
 
 
 Key Benefits
@@ -58,7 +66,7 @@ Geometry and texture/color in one workflow.
 2. Affordability and flexibility.
 Depending on the end use application almost any camera will work given there is enough light and your post processing software is robust.
 3. Real Time Feedback & Processing*
-*as models improve. [Ingenuity Drone](https://mars.nasa.gov/technology/helicopter/#) relies on photogrammetry-based onboard processing for ground distance estimation, showcasing the efficacy of passive sensing approaches in complex environments.
+*as models improve. Nasa's [Ingenuity Drone](https://mars.nasa.gov/technology/helicopter/#) relies on photogrammetry-based onboard processing for ground distance estimation, showcasing the efficacy of passive sensing approaches in complex environments.
 
 <p><img src="images/lidar_vs_photogrammetry_drone.jpg" alt="Drone imaging"></p>
 
@@ -88,10 +96,8 @@ iPhone and Android apps for photogrammetry and now LiDAR scanning have multiplie
 [Polycam](https://poly.cam/)<br>
 [Rekrei](https://projectmosul.org/)<br>
 [Adobe Aero](https://www.adobe.com/products/aero.html)<br>
-[ScandyPro](https://www.scandy.co/apps/scandy-pro)<br>
-[Bellus](https://www.bellus3d.com/faceapp/)<br>
+[ScandyPro](https://www.scandy.co/apps/scandy-pro)<br> - Real Time Meshing
 
-<img src="images/bellus.jpg" alt="Bellus">
 
 [Scan the World](https://www.myminifactory.com/scantheworld/)<br>
 [Quixel Megascans](https://quixel.com/megascans)
@@ -103,7 +109,7 @@ iPhone and Android apps for photogrammetry and now LiDAR scanning have multiplie
 Creality Ferret Pro
 Iphone 13
 
-<p>Intrinsics and extrinsics parameters</p>
+
 
 
 # Light Field