Corridor Key vs Robust Video Matting

Corridor Key is a free browser-based AI green-screen keyer that removes a video background and replaces it with a solid color, still image, or video. It accepts standard MP4 clips and returns re-encoded H.264 MP4 files. The service says its AI preserves details including flyaway hair, fur, glass, eyewear, and sheer fabric. Fast Mode processes an eight-second clip in seconds; Full Mode takes longer for sharper edge detail. No account or installation is required, and the free plan has no daily or monthly usage cap, although each clip can be up to eight seconds. It runs in desktop, tablet, and mobile browsers, with processing on its servers. Uploaded clips are sent to a Hugging Face Space running BiRefNet. Corridor Key says it does not store clips or outputs on its own servers; Hugging Face terms apply while files are there. HTTPS protects transmission. Availability can depend on Space downtime or GPU queues, and quality varies with edges, motion, lighting, and source quality.

Robust Video Matting is a free project for separating people from video backgrounds. It processes frames with a recurrent neural network that carries temporal memory, and the project says it can perform matting in real time without additional inputs. A browser webcam demo runs the model live and can visualize its recurrent states. The conversion API accepts a video or image sequence and can produce a composited video or PNG sequence, optionally including alpha and foreground outputs.

Models are available for PyTorch, TorchHub, TorchScript, ONNX, TensorFlow, TensorFlow.js, and CoreML. MobileNetv3 is recommended for most uses; ResNet50 is larger and described as offering small performance improvements. The README reports GPU throughput figures, including 4K at 76 FPS and HD at 104 FPS on a GTX 1080 Ti, and 4K at 154 FPS and HD at 172 FPS on an RTX 3090 with FP16 under specified settings. The project cautions that file conversion runs much slower because its script does not use hardware video encoding or decoding or parallel tensor transfers. CoreML models require iOS 13 or later and do not support dynamic resolution. The code is GPL-3.0 licensed.