-2 opencv resource_error ai_generated true

cv::error: (-2:Unspecified error) FAILED: fs.is_open(). Can't open file: 'model.prototxt' in function 'ReadProtoFromTextFile'

ID: opencv/dnn-caffe-model-load-failed

Also available as: JSON · Markdown · 中文
93%Fix Rate
87%Confidence
1Evidence
2023-08-20First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
4.5.0 active — — —
4.6.0 active — — —
4.7.0 active — — —
4.8.0 active — — —
4.9.0 active — — —
4.10.0 active — — —

Root Cause

Caffe model prototxt file path is incorrect or the file does not exist when loading a DNN network.

generic

中文

加载DNN网络时，Caffe模型的prototxt文件路径不正确或文件不存在。

Official Documentation

https://docs.opencv.org/4.x/d6/d0f/group__dnn.html#ga29f34df9b6c6f0d44e5f3b9e2b8f0d4e

Workarounds

  1. 95% success Use an absolute path to the prototxt file. Example: cv::dnn::Net net = cv::dnn::readNetFromCaffe("/absolute/path/to/deploy.prototxt", "/absolute/path/to/model.caffemodel"); 
    Use an absolute path to the prototxt file. Example: cv::dnn::Net net = cv::dnn::readNetFromCaffe("/absolute/path/to/deploy.prototxt", "/absolute/path/to/model.caffemodel");
  2. 90% success Verify file existence using std::ifstream before loading: std::ifstream f("deploy.prototxt"); if (!f.good()) { std::cerr << "File not found"; } 
    Verify file existence using std::ifstream before loading: std::ifstream f("deploy.prototxt"); if (!f.good()) { std::cerr << "File not found"; }

中文步骤

  1. Use an absolute path to the prototxt file. Example: cv::dnn::Net net = cv::dnn::readNetFromCaffe("/absolute/path/to/deploy.prototxt", "/absolute/path/to/model.caffemodel");
  2. Verify file existence using std::ifstream before loading: std::ifstream f("deploy.prototxt"); if (!f.good()) { std::cerr << "File not found"; }

Dead Ends

Common approaches that don't work:

  1. 80% fail

    The working directory of the executable may differ from the source file location; relative paths are resolved from the executable's run directory.

  2. 60% fail

    The function expects the prototxt file as the first argument; swapping arguments leads to a different error but often confuses users into thinking the file is missing.