Elgato 4K X: Elgato HDR: A Userspace Capture Path for Elgato 4K X 10-bit Mode

The open-source Elgato HDR project released a macOS app that captures and records 10-bit HDR video from the Elgato 4K X by bypassing Apple's default 8-bit webcam driver, using a root helper tool called uvc_capture.c built on libusb to detach the kernel driver and talk directly to the device over USB Video Class. The app renders the captured 10-bit P010 data with Metal and records to HDR10 HEVC files, requires macOS 14 or newer on Apple Silicon, and its repository documents development assistance from Claude Opus 4.8, 5.5, and Claude Fable 5.1. The project notes other cards exposing a P010 UVC format may work but remain untested, and that the root helper requires an administrator password on first launch while the locally signed app needs manual quarantine removal via xattr if not built from source.

Evidence at a glance Based on the linked sources. The author's reported result and independent confirmation are separate checks. - AI involvement - Reported models: Claude. Tools: libusb, Xcode Command Line Tools, Homebrew. The writeup below describes the work attributed to AI. - Reported result - Works. This is the directory's source-based outcome classification. - Independent confirmation - Not reported. - Human work and limitations - The project uses a root helper to bypass kernel drivers, which requires an administrator password on the first launch. The app is signed for local use and requires manual quarantine removal via xattr if not built from source. Original sources What was done Elgato HDR is a macOS app that bypasses Apple's 8-bit driver limitations to capture and record 10-bit HDR video from the Elgato 4K X, providing live HDR preview and multi-format export. The Elgato HDR https://raw.githubusercontent.com/talkaboutdesign/elgato-hdr/HEAD/README.md project provides a native macOS solution to capture 10-bit HDR signals from the Elgato 4K X. While the device advertises a 10-bit P010 format over USB, Apple's default webcam driver restricts access to 8-bit modes. The project uses a root helper tool, uvc capture.c , which utilizes libusb to detach the kernel driver and communicate directly with the device via the USB Video Class protocol. The application renders the captured 10-bit data using Metal and supports recording to HDR10 HEVC files. The repository documents that the software was developed with assistance from various AI models, including Claude Opus 4.8, 5.5, and Claude Fable 5.1. The tool is designed for macOS 14 or newer on Apple Silicon. While primarily tested for the Elgato 4K X, the documentation notes that other cards exposing a P010 UVC format may function, though they remain untested. The project includes features such as live HDR preview, facecam overlays, and a recordings library. Reproduce it Clone the repository, install libusb and Xcode Command Line Tools, then execute ./build.sh to generate the application bundle.