The Direct Kernel Capture Manual
The Bottleneck of Screen Capture
In Windows and macOS, screen capture (OBS) is a high-overhead task. The OS has to copy frames from the GPU to the CPU, encode them, and then often copy them back. This leads to high CPU usage and dropped frames during recording. Tebian uses Direct Kernel Capture (PipeWire DMA-BUF) to achieve zero-overhead screen recording.
This manual explains the C-level magic that allows you to record 4K 60FPS video with almost 0% CPU impact.
1. The Logic of DMA-BUF
DMA-BUF (Direct Memory Access Buffer) is a Linux kernel feature that allows different hardware drivers (GPU and CPU) to share memory buffers. In Tebian, when your screen is rendered by Sway, the frame sits in a buffer on your GPU. Using PipeWire, we pass a "Pointer" to that buffer directly to OBS.
Zero-Copy Recording
Because OBS has a pointer to the existing GPU memory, it doesn't need to "Capture" or "Copy" the image. It simply reads the data that is already there. This is Zero-Copy Architecture. While Windows is busy moving gigabytes of pixel data per second, Tebian is just moving pointers. This results in the lowest possible recording latency in the world.
2. Hardware Encoding: NVENC and AMF
Tebian's Hardware Detect system ensures that your GPU's dedicated encoding chips are active. We pre-configure OBS to use NVENC (NVIDIA) or AMF (AMD) for H.264 and AV1 encoding.
- Low Latency: Encoding happens on a dedicated piece of silicon, leaving your CPU free for the game or app.
- AV1 Support: Tebian is ready for the future of streaming with native AV1 hardware support on modern cards.
Conclusion: The Ultimate Streamer Foundation
The Direct Kernel Capture Manual proves that Linux isn't just "good enough" for streamers—it is the Superior Engineering Choice. By using kernel-level buffer sharing and hardware-native encoding, you get a smoother stream and a faster PC. One ISO. One menu. Pro-grade recording.