为什么我已经安装了 cuda toolkit 和 cudnn ，但是 opencv 却找不到 cudnn 呢？

Question

我需要实现『在 ubuntu 上安装支持 cuda 的 opencv，用于 python 调用 opencv+nvidia GPU』

所以，我按照下面的教程安装了 cuda toolkit

cuda toolkit Download

按照下面的教程安装了 cudnn

NVIDIA Deep Learning cuDNN Documentation

按照下面的教程安装了 opencv

Installing OpenCV 4 with CUDA in Ubuntu 22.04

然后编译 opencv 的时候，报错找不到 cudnn

可以找到 cuda，但是找不到 cudnn

但是我这里是有 cudnn 的：

─➤  ls -alh  /usr/local/cuda/lib64/libcudnn*

lrwxrwxrwx 1 root root   23 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_adv_infer.so -> libcudnn_adv_infer.so.8
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_adv_infer.so.8 -> libcudnn_adv_infer.so.8.8.0
-rwxr-xr-x 1 root root 120M Mar  9 12:28 /usr/local/cuda/lib64/libcudnn_adv_infer.so.8.8.0
-rw-r--r-- 1 root root 123M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_adv_infer_static.a
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_adv_infer_static_v8.a -> libcudnn_adv_infer_static.a
lrwxrwxrwx 1 root root   23 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_adv_train.so -> libcudnn_adv_train.so.8
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_adv_train.so.8 -> libcudnn_adv_train.so.8.8.0
-rwxr-xr-x 1 root root 114M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_adv_train.so.8.8.0
-rw-r--r-- 1 root root 116M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_adv_train_static.a
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_adv_train_static_v8.a -> libcudnn_adv_train_static.a
lrwxrwxrwx 1 root root   23 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_cnn_infer.so -> libcudnn_cnn_infer.so.8
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_cnn_infer.so.8 -> libcudnn_cnn_infer.so.8.8.0
-rwxr-xr-x 1 root root 613M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_cnn_infer.so.8.8.0
-rw-r--r-- 1 root root 797M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_cnn_infer_static.a
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_cnn_infer_static_v8.a -> libcudnn_cnn_infer_static.a
lrwxrwxrwx 1 root root   23 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_cnn_train.so -> libcudnn_cnn_train.so.8
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_cnn_train.so.8 -> libcudnn_cnn_train.so.8.8.0
-rwxr-xr-x 1 root root 100M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_cnn_train.so.8.8.0
-rw-r--r-- 1 root root 150M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_cnn_train_static.a
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_cnn_train_static_v8.a -> libcudnn_cnn_train_static.a
lrwxrwxrwx 1 root root   23 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_ops_infer.so -> libcudnn_ops_infer.so.8
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_ops_infer.so.8 -> libcudnn_ops_infer.so.8.8.0
-rwxr-xr-x 1 root root  87M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_ops_infer.so.8.8.0
-rw-r--r-- 1 root root  90M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_ops_infer_static.a
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_ops_infer_static_v8.a -> libcudnn_ops_infer_static.a
lrwxrwxrwx 1 root root   23 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_ops_train.so -> libcudnn_ops_train.so.8
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_ops_train.so.8 -> libcudnn_ops_train.so.8.8.0
-rwxr-xr-x 1 root root  68M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_ops_train.so.8.8.0
-rw-r--r-- 1 root root  68M Mar  9 12:29 /usr/local/cuda/lib64/libcudnn_ops_train_static.a
lrwxrwxrwx 1 root root   27 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn_ops_train_static_v8.a -> libcudnn_ops_train_static.a
lrwxrwxrwx 1 root root   13 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn.so -> libcudnn.so.8
lrwxrwxrwx 1 root root   17 Mar  9 12:20 /usr/local/cuda/lib64/libcudnn.so.8 -> libcudnn.so.8.8.0
-rwxr-xr-x 1 root root 147K Mar  9 12:29 /usr/local/cuda/lib64/libcudnn.so.8.8.0

为什么呢？

---

贴一下附件信息

─➤  nvcc --version
nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2023 NVIDIA Corporation
Built on Tue_Feb__7_19:32:13_PST_2023
Cuda compilation tools, release 12.1, V12.1.66
Build cuda_12.1.r12.1/compiler.32415258_0