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API Coverage

This page summarizes what percentage of OpenCV's API is exposed through opencv-ruby.

Coverage Summary

Category Coverage
Core Modules ~95%
Extra Modules ~60%
Overall ~85%

The bindings expose 1,600+ classes, enums, and types from OpenCV.

Modules Included

Core Modules (opencv)

These are the main modules that ship with OpenCV:

Module Status Description
core Full Matrix operations, basic structures, linear algebra
imgproc Full Image processing (filtering, transforms, drawing)
imgcodecs Full Image file reading and writing
videoio Full Video capture and writing
highgui Full GUI windows and trackbars
video Full Video analysis (optical flow, tracking)
calib3d Full Camera calibration and 3D reconstruction
features2d Full Feature detection and description
objdetect Full Object detection (cascades, HOG, ArUco)
dnn Full Deep neural network inference
ml Full Machine learning algorithms
flann Full Fast approximate nearest neighbors
photo Full Computational photography
stitching Full Image stitching / panoramas

Contrib/Extra Modules

Module Status Notes
aruco Full ArUco marker detection (part of objdetect in 4.x)
barcode Full Barcode detection (OpenCV 4.8+)
cuda Partial Core CUDA support only, not GPU algorithms
cudaarithm Not included —
cudafilters Not included —
cudev Not included —

What's Not Included

CUDA GPU Modules

The CUDA-accelerated modules are not exposed:

  • cuda (partial - device info only)
  • cudaarithm
  • cudabgsegm
  • cudacodec
  • cudafeatures2d
  • cudafilters
  • cudaimgproc
  • cudaobjdetect
  • cudaoptflow
  • cudastereo
  • cudawarping

Reason: CUDA support requires specific hardware and significantly complicates the build process. The CPU implementations of all algorithms are available.

Platform-Specific Features

  • DirectX interop (Windows-only)
  • VA-API (Linux Intel GPU)
  • Some OpenCL features

Deprecated APIs

Legacy APIs marked deprecated in OpenCV 4.x are not included.

Enums Coverage

All public enums from included modules are exposed. Examples:

  • Cv::ImreadModes - Image loading options
  • Cv::ImwriteFlags - Image saving options
  • Cv::ColorConversionCodes - Color space conversions
  • Cv::ThresholdTypes - Thresholding methods
  • Cv::BorderTypes - Border handling
  • Cv::MorphTypes - Morphological operations
  • Cv::InterpolationFlags - Resize/remap interpolation
  • And 200+ more...

Verifying Coverage

To see what's available, explore the API Reference or use Ruby introspection:

require 'opencv-ruby'

# List all classes in Cv module
Cv.constants.select { |c| Cv.const_get(c).is_a?(Class) }

# List methods on a class
Cv::Mat.instance_methods(false)

# List enum values
Cv::ImreadModes.constants

See Also

Requesting Additional Coverage

If you need an OpenCV feature that isn't currently exposed, please:

  1. Check the API Reference to confirm it's not already available
  2. Open an issue at github.com/cfis/opencv-ruby
  3. Include the C++ function/class name from the OpenCV documentation