Hardware‑Accelerated FFmpeg: NVENC, VAAPI, and VideoToolbox

Hardware encoders can be multiple times faster than software, with some trade‑offs in compression efficiency. Here’s how to enable them on common platforms.

Pros and Cons

• Pros: speed, lower CPU usage.
• Cons: slightly lower compression efficiency than slow software presets; limited filter support on GPU.

Examples

# NVIDIA NVENC (H.264)
ffmpeg -i in.mp4 -c:v h264_nvenc -preset p5 -rc vbr -cq 23 -b:v 5M -maxrate 7M -bufsize 10M \
  -c:a aac -b:a 160k out_nvenc.mp4

# Intel VAAPI (Linux)
ffmpeg -vaapi_device /dev/dri/renderD128 -i in.mp4 \
  -vf 'format=nv12,hwupload,scale_vaapi=w=1920:h=1080' -c:v h264_vaapi -b:v 5M -c:a copy out_vaapi.mp4

# Apple VideoToolbox (macOS)
ffmpeg -i in.mp4 -c:v h264_videotoolbox -b:v 5M -maxrate 7M -bufsize 10M \
  -c:a aac -b:a 160k out_vt.mp4

Pitfalls

• Ensure drivers/devices are set up (Linux: permissions for /dev/dri).
• Not all filters run on GPU; sometimes frames must be uploaded/downloaded.

Use hardware when turnaround time matters; for maximum compression, software encoders at slower presets still win.