OpenCV checkHardwareSupport_0

checkHardwareSupport asks OpenCV a boring but occasionally useful question: is a specific CPU feature enabled in this build? You give it a feature code as an integer, it gives you back a boolean. That's the whole node. It's a diagnostic utility - think of it as the "About" dialog for OpenCV's SIMD acceleration, not an image operation.

Why would you ever care? Because OpenCV's performance on CPU work - resizing, filtering, color conversion, the stuff this pack does between generations - depends heavily on SIMD instruction sets like SSE and AVX. If you're trying to figure out why some OpenCV-heavy node in your graph is slow, or whether your ComfyUI Python environment is actually seeing your CPU's vector extensions (say, inside a container or a weird portable build), this node is the direct answer.

The feature codes. This is where the node gets awkward: feature is a raw INT, and you need OpenCV's CPU_* constants to know what you're asking about. The relevant ones:

• cv2.CPU_MMX = 1, CPU_SSE = 2, CPU_SSE2 = 3, CPU_SSE3 = 4
• CPU_SSE4_1 = 6, CPU_SSE4_2 = 7
• CPU_AVX = 9, CPU_AVX2 = 10, CPU_FMA3 = 11
• CPU_AVX512_SKX = 256 (the big one)

So to ask "does this build have AVX2?" you'd feed 10. Nothing in the node labels these - it's just an int in, bool out, which is exactly the kind of rough auto-generated edge this pack is known for. If you want the constants, they're cv2.CPU_* in a Python shell, or just look up the number once.

Where it doesn't help. It's about CPU features only - it won't tell you about GPU, CUDA, or OpenCL support, and ComfyUI's heavy lifting is on the GPU anyway, so this node is genuinely a corner utility. It's the kind of thing you run once out of curiosity, then never touch. Which is fine: it costs nothing to have around.

Install. Standard for the pack - ComfyUI Manager → search "OpenCV", or:

cd ComfyUI/custom_nodes
git clone https://github.com/geroldmeisinger/opencv-comfyui
pip install opencv-python-contrib

Restart after. No model files, no extra dependencies beyond OpenCV itself. And for completeness: checkHardwareSupport_0 has no _1 twin in the same form as the other nodes - check the pack's node list if you see a variant; most of these one-off utilities appear once. Either way, the pack's standing advice applies: auto-generated, rough edges, "expect dragons."