Below are some basic machine learning skills

• Clustering
  • K-means
• Instance-based Algorithms
  • KNN
• Bayesian Algorithms
  • Naive Bayes
    • 假设输入的feature之间互相独立，因此概率的联合分布函数可以写成连乘
• Regression
  • OLSR，最小二乘
  • Linear Regression
  • Logistic Regression
• Decision Tree
  • ID3
  • C4.5
  • CART
• Ensemble Algorithms：多个弱分类器共同构成强分类器
  • Boosting
  • Bagging
  • Random Forest
  • Gradient Boosted Regression Trees
• Artificial Neural Network
  • Perceptron
• SVM
• Dimensionality Reduction Algorithms
  • PCA
  • PCR

Reference

机器学习算法集锦：从贝叶斯到深度学习及各自优缺点

XR devices leverages variety of algorithms, mainly include computer vision and computer graphics categories.

VR, AR introduction.

Introduction for software development in Apple platforms

Opencv has a lot of useful functions.

Show image/video stream

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while True:
    cv2.imshow(img)
    cv2.waitKey(1)

Color Related

Color Space Convert

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gray_img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

Histogram and Backprojection

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hist = cv2.calcHist([img], [0, 1], None, [180, 256], [0, 180, 0, 256])
mask = cv2.calcBackProject([target], [0, 1], hist, [0, 180, 0, 256], 1)

Otsu threshold

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_, mask = cv2.threshold(img[:, :, 1], 0, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU)

Geometric

Contour of images

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_, contours, _ = cv2.findContours(mask, cv2.RETR_CCOMP, cv2.CHAIN_APPROX_SIMPLE)

Convex Hull and Convex Defect

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hull = cv2.convexHull(contour, returnPoints=False)
defects = cv2.convexityDefects(contour, hull)

There are a lot of application development paths for Microsoft MixedReality platforms. This post covers things including OpenXR, Unity, Stereo Kit, MRTK and etc.

Captures some features of Microsoft HoloLens.

Anchor: a kind of data structure in AR field, which represents a precise point of interest in 3D space that can be shared across users, devices, and time

Microsoft Azure Spatial Anchors is a service that can store the local world anchors to the cloud and share the anchors among different platforms, see the table blow. ASA (Azure Spatial Anchors) enables building apps that can map, persist, and share 3D content from room-scale to real world-scale.

Microsoft Azure Remote Rendering is a service that can render high-quality, interactive 3D content, and stream it to your devices in real time.

ARKit is a software framework for iOS to create AR applications. It support features of device tracking, plane detection, and could allow apps to place virtual objects on top of real-world environment.