OpenCV Module Coverage
This table describes the OpenCvSharp5 bindings on main and the native modules included in its packaged runtime profiles. Published NuGet versions may predate changes on main. It does not describe OpenCvSharp4. OpenCvSharp exposes selected APIs from each listed module; a check mark does not mean that every OpenCV function, class, overload, or backend in that module has a .NET binding. Search the API reference for a particular API before depending on it.
| Mark | Meaning |
|---|---|
| ✓ | OpenCvSharp has bindings for at least part of the module, and the profile builds the corresponding native exports. |
| — | The profile does not provide OpenCvSharp bindings for that module. A managed declaration may still be present, but calling it with this runtime can fail because the native export is absent. |
Full covers the Windows, macOS, and Linux full runtime builds. Headless is the official Linux headless build, which differs from full by disabling highgui. Slim covers the Windows and official Linux slim builds. Android is the preview OpenCvSharp5.runtime.android package. Platform backends and third-party dependencies can still differ within a profile; for example, Windows ARM64 does not include the FFmpeg video I/O plugin. This matrix describes module availability, not every backend or codec.
OpenCV modules and API groups
OpenCV 5 split the former calib3d module into geometry, calib, stereo, and ptcloud, and renamed features2d to features. Its aruco and barcode APIs are part of objdetect; they are shown separately because OpenCvSharp exposes separate binding groups for them.
| Module or API group | Full | Headless | Slim | Android | Notes |
|---|---|---|---|---|---|
core |
✓ | ✓ | ✓ | ✓ | Core types and operations; individual APIs may depend on other modules. |
imgproc |
✓ | ✓ | ✓ | ✓ | Some image processing APIs moved to other OpenCV 5 modules. |
imgcodecs |
✓ | ✓ | ✓ | ✓ | Codec availability depends on the build. |
geometry |
✓ | ✓ | ✓ | — | Includes geometry APIs formerly in calib3d. |
calib |
✓ | ✓ | ✓ | — | Camera calibration. |
stereo |
✓ | ✓ | ✓ | — | Stereo matching. |
ptcloud |
✓ | ✓ | ✓ | — | Point cloud and odometry APIs. |
features |
✓ | ✓ | ✓ | — | Formerly features2d. |
flann |
✓ | ✓ | ✓ | — | Approximate nearest-neighbor search. |
objdetect |
✓ | ✓ | ✓ | — | Includes selected APIs backed by contrib xobjdetect. |
aruco (objdetect APIs) |
✓ | ✓ | ✓ | — | Marker and ChArUco APIs use the existing objdetect module. |
barcode (objdetect APIs) |
✓ | ✓ | ✓ | — | Barcode detection is part of objdetect in OpenCV 5. |
photo |
✓ | ✓ | ✓ | — | Computational photography. |
video |
✓ | ✓ | ✓ | — | Video analysis; distinct from videoio. |
dnn |
✓ | ✓ | — | — | Deep neural networks. |
stitching |
✓ | ✓ | — | — | Panorama stitching. |
videoio |
✓ | ✓ | — | — | Capture and writing; available backends vary by platform. |
highgui |
✓ | — | — | — | Native windows and UI controls. |
opencv_contrib modules
These tables include contrib modules with and without OpenCvSharp bindings. OpenCV 5 places ml in opencv_contrib. xobjdetect supplies some objdetect bindings above, including cascade and HOG APIs, rather than a separate managed API group. Some contrib modules remain in slim even though that native binding build sets NO_CONTRIB=ON. This is why the OpenCV build list alone cannot determine whether a particular OpenCvSharp binding is available.
| Module | Full | Headless | Slim | Android | Notes |
|---|---|---|---|---|---|
bgsegm |
✓ | ✓ | ✓ | — | Background segmentation. |
img_hash |
✓ | ✓ | ✓ | — | Perceptual image hashes. |
ml |
✓ | ✓ | ✓ | — | Machine learning. |
xobjdetect |
✓ | ✓ | ✓ | — | Selected APIs appear under OpenCvSharp's objdetect bindings. |
ximgproc |
✓ | ✓ | ✓ | — | Extended image processing. |
xphoto |
✓ | ✓ | ✓ | — | Extended photography. |
bioinspired |
✓ | ✓ | — | — | |
ccalib |
✓ | ✓ | — | — | |
dnn_objdetect |
✓ | ✓ | — | — | |
dnn_superres |
✓ | ✓ | — | — | |
dpm |
✓ | ✓ | — | — | |
face |
✓ | ✓ | — | — | |
fuzzy |
✓ | ✓ | — | — | |
hfs |
✓ | ✓ | — | — | |
intensity_transform |
✓ | ✓ | — | — | |
line_descriptor |
✓ | ✓ | — | — | Named line_descriptors in the managed source tree. |
optflow |
✓ | ✓ | — | — | |
phase_unwrapping |
✓ | ✓ | — | — | |
plot |
✓ | ✓ | — | — | |
quality |
✓ | ✓ | — | — | |
rapid |
✓ | ✓ | — | — | |
reg |
✓ | ✓ | — | — | |
rgbd |
✓ | ✓ | — | — | |
saliency |
✓ | ✓ | — | — | |
shape |
✓ | ✓ | — | — | |
signal |
✓ | ✓ | — | — | |
structured_light |
✓ | ✓ | — | — | |
superres |
✓ | ✓ | — | — | |
surface_matching |
✓ | ✓ | — | — | |
text |
✓ | ✓ | — | — | Some OCR APIs require Tesseract. |
tracking |
✓ | ✓ | — | — | |
videostab |
✓ | ✓ | — | — | Video stabilization from in-memory frames. |
wechat_qrcode |
✓ | ✓ | — | — | |
xfeatures2d |
✓ | ✓ | ✓ | — | Slim exposes BRISK, KAZE, AKAZE, and AGAST; the other bindings remain full/headless only. |
xstereo |
✓ | ✓ | — | — |
The following opencv_contrib modules have no OpenCvSharp5 bindings, including in the full runtime. Some may be built as dependencies or for upstream internal use, but they do not expose a corresponding OpenCvSharp API.
| Module | Full | Headless | Slim | Android | Notes |
|---|---|---|---|---|---|
alphamat |
— | — | — | — | |
cannops |
— | — | — | — | |
cnn_3dobj |
— | — | — | — | |
cvv |
— | — | — | — | |
datasets |
— | — | — | — | |
dnns_easily_fooled |
— | — | — | — | |
fastcv |
— | — | — | — | |
freetype |
— | — | — | — | The library may be bundled for other features; its module API is not wrapped. |
gapi |
— | — | — | — | Disabled in the full OpenCV build configuration. |
hdf |
— | — | — | — | |
ovis |
— | — | — | — | |
sfm |
— | — | — | — | |
viz |
— | — | — | — | |
cudev |
— | — | — | — | CUDA infrastructure; no OpenCvSharp CUDA bindings. |
cudaarithm |
— | — | — | — | |
cudabgsegm |
— | — | — | — | |
cudacodec |
— | — | — | — | |
cudafeatures2d |
— | — | — | — | |
cudafilters |
— | — | — | — | |
cudaimgproc |
— | — | — | — | |
cudalegacy |
— | — | — | — | |
cudaobjdetect |
— | — | — | — | |
cudaoptflow |
— | — | — | — | |
cudastereo |
— | — | — | — | |
cudawarping |
— | — | — | — |
Language-specific julia and matlab contrib modules, and the OpenCV java, js, objc, and python binding generators, are outside the .NET binding scope. OpenCV's ts module provides test support, while world aggregates modules; neither has a separate end-user API row here.
Profile details and limits
- Full and headless Linux builds select the same non-GUI OpenCV modules. Headless turns GTK off and builds the native binding with
NO_HIGHGUI=ON. - Slim builds use the module list in
cmake/opencv_build_options_slim.cmakeand disablednn,stitching,videoio,highgui, and most contrib bindings. The slimNO_CONTRIBswitch does not remove the lightweight contrib bindings marked above. - Android builds only
core,imgproc, andimgcodecsnative bindings.Subdiv2D,IntelligentScissorsMB, andGoodFeaturesToTrackare unavailable there because OpenCV 5 places them ingeometry,photo, andfeatures, respectively. See Android runtime support. - WebAssembly has its own build and test configuration and is not represented by the four packaged profiles in this table. Check the WebAssembly workflow and test the specific API you need in a browser.
Why these modules are in slim
The slim profile aims to keep common in-memory processing useful without requiring GUI, media capture, DNN, or their extra runtime dependencies. The decision is based on the OpenCV module dependency graph and the exports actually enabled in OpenCvSharp. A compiled OpenCV module alone does not make its managed API usable.
| Decision | Modules or APIs | Reason |
|---|---|---|
| Keep the base | core, imgproc, imgcodecs, geometry, calib, stereo, ptcloud, features, flann, objdetect, photo, ml, video |
These cover the main image, feature, calibration, analysis, and point cloud workflows. video processes frames already in memory; capture and codecs belong to videoio. ptcloud uses modules already in this profile rather than a separate third-party runtime. |
| Keep selected contrib | bgsegm, img_hash, ximgproc, xphoto, xobjdetect, and selected xfeatures2d APIs |
These provide commonly useful algorithms on top of the slim base without introducing DNN, GUI, or media I/O dependencies. Some larger ximgproc and xfeatures2d binding groups remain excluded. |
| Include relocated APIs | ArUco, barcode, cascade and HOG detection, BRISK, KAZE, AKAZE, AGAST | OpenCV 5 moved these APIs into objdetect, xobjdetect, or xfeatures2d. ArUco uses the already included objdetect module; the selected feature detectors use the already included xfeatures2d module. Their previous NO_CONTRIB guards would otherwise hide useful APIs despite those native dependencies being present. |
| Exclude heavy profile changes | dnn, videoio, highgui, stitching, and contrib bindings that require those modules or optional external integrations |
These change the size or runtime dependency goals of slim. Full or headless is the appropriate profile when they are needed. |
| Leave specialized contrib in full/headless | Modules such as ccalib, rapid, reg, rgbd, structured_light, and surface_matching |
Their narrower use cases do not yet justify expanding the default slim exports. Their dependencies and incremental package size should be measured before moving them into slim. |
The retained modules are not all equally small. In particular, ptcloud, ml, ximgproc, and xfeatures2d warrant size checks when the profile is next rebuilt. The choices above preserve their useful APIs while avoiding additional modules; they are not a numerical size guarantee.
This is a module-level guide to the source and build configuration, not a promise of complete API parity or a guarantee that an optional backend is installed. For package names, see Choose a Version and Package.