DevLog 20250506 C# Video Processing Foundation Library

Today I need to find a suitable foundational library for video processing. FFMpegCore works for one-shot things but despite a fluent API, its interface is still too command line like. Here is what I found out: OpenCvSharp LibVLCSharp FFMediaToolkit Frames ✅ decode / encode ✅ (via callbacks) ❓ Audio ❌ ✅ decode / encode / mux ❓ Extra libs ~5 MB/platform +7 MB +7 MB Licence Apache‑2.0 LGPLv2.1 MIT Platforms Win / mac / Linux / Arm Win / mac / Linux / iOS / Android Win / mac / Linux LibVLCSharp seems more focused on directly displaying things (e.g. in Xamarine and WPF) instead of low-level API based processing; FFMediaToolkit, on the other hand, still depends on FFMPEG and can't avoid licensing issue. Eventually, I had to go with separate video + audio processing in favor of OpenCvSharp (it's Apache-2.0 by the way). Notice OpenCVSharp has some advantage over EmguCV for custom dev: OpenCvSharp Emgu.CV Licence Apache-2.0 (fully permissive) GPL v3 or commercial licence Interop model Pure P/Invoke (no C++/CLI), works on any .NET core runtime Historically C++/CLI wrapper (needs Windows for full feature set), .NET Standard P/Invoke layer added later NuGet size (native) 4–6 MB per RID (modular runtime packages) 30 MB + for the “opencv‑world” monolith, or 90 MB for emgucv‑runtime‑ubuntu GPU (CUDA) support Provided in separate OpenCvSharp4.runtime.dnn package Official CUDA builds, but Windows‑only binaries unless you compile yourself API surface ~1:1 with OpenCV C++ names (easy to port C++ samples) Thicker .NET façade (e.g. Image types), extra helpers Cross‑platform stability Actively tested on Windows / Linux / macOS / arm64 Windows the main focus; Linux/macOS possible with libopencv from distro or big runtime package Learning curve If you know OpenCV C++ you feel at home Higher‑level abstractions can be friendlier for newcomers Commercial support Community‑driven Paid licences & support available from Emgu CV, Inc.

May 7, 2025 - 04:17

DevLog 20250506 C# Video Processing Foundation Library

Today I need to find a suitable foundational library for video processing. FFMpegCore works for one-shot things but despite a fluent API, its interface is still too command line like.

Here is what I found out:

	OpenCvSharp	LibVLCSharp	FFMediaToolkit
Frames	✅ decode / encode	✅ (via callbacks)	❓
Audio	❌	✅ decode / encode / mux	❓
Extra libs	~5 MB/platform	+7 MB	+7 MB
Licence	Apache‑2.0	LGPLv2.1	MIT
Platforms	Win / mac / Linux / Arm	Win / mac / Linux / iOS / Android	Win / mac / Linux

LibVLCSharp seems more focused on directly displaying things (e.g. in Xamarine and WPF) instead of low-level API based processing; FFMediaToolkit, on the other hand, still depends on FFMPEG and can't avoid licensing issue. Eventually, I had to go with separate video + audio processing in favor of OpenCvSharp (it's Apache-2.0 by the way).

Notice OpenCVSharp has some advantage over EmguCV for custom dev:

	OpenCvSharp	Emgu.CV
Licence	Apache-2.0 (fully permissive)	GPL v3 or commercial licence
Interop model	Pure P/Invoke (no C++/CLI), works on any .NET core runtime	Historically C++/CLI wrapper (needs Windows for full feature set), .NET Standard P/Invoke layer added later
NuGet size (native)	4–6 MB per RID (modular runtime packages)	30 MB + for the “opencv‑world” monolith, or 90 MB for emgucv‑runtime‑ubuntu
GPU (CUDA) support	Provided in separate OpenCvSharp4.runtime.dnn package	Official CUDA builds, but Windows‑only binaries unless you compile yourself
API surface	~1:1 with OpenCV C++ names (easy to port C++ samples)	Thicker .NET façade (e.g. `Image` types), extra helpers
Cross‑platform stability	Actively tested on Windows / Linux / macOS / arm64	Windows the main focus; Linux/macOS possible with `libopencv` from distro or big runtime package
Learning curve	If you know OpenCV C++ you feel at home	Higher‑level abstractions can be friendlier for newcomers
Commercial support	Community‑driven	Paid licences & support available from Emgu CV, Inc.