Merge pull request #28678 from omrope79:caffe-importer-cleanup

Caffe importer cleanup #28678

Merge with: https://github.com/opencv/opencv_extra/pull/1324

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
- [x] The feature is well documented and sample code can be built with the project CMake

samples/android/mobilenet-objdetect/CMakeLists.txt

@@ -1,24 +1,20 @@
 set(sample example-mobilenet-objdetect)
 
-ocv_download(FILENAME "mobilenet_iter_73000.caffemodel"
-             HASH "bbcb3b6a0afe1ec89e1288096b5b8c66"
-             URL
-               "${OPENCV_MOBILENET_SSD_WEIGHTS_URL}"
-               "$ENV{OPENCV_MOBILENET_SSD_WEIGHTS_URL}"
-               "https://raw.githubusercontent.com/chuanqi305/MobileNet-SSD/97406996b1eee2d40eb0a00ae567cf41e23369f9/mobilenet_iter_73000.caffemodel"
-             DESTINATION_DIR "${CMAKE_CURRENT_LIST_DIR}/res/raw"
-             ID OPENCV_MOBILENET_SSD_WEIGHTS
-             STATUS res)
+# Explicitly ensure resource directories exist to guarantee smooth resource compiling
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/res/raw")
 
-ocv_download(FILENAME "deploy.prototxt"
-             HASH "f1978dc4fe20c680e850ce99830c5945"
-             URL
-               "${OPENCV_MOBILENET_SSD_CONFIG_URL}"
-               "$ENV{OPENCV_MOBILENET_SSD_CONFIG_URL}"
-               "https://raw.githubusercontent.com/chuanqi305/MobileNet-SSD/97406996b1eee2d40eb0a00ae567cf41e23369f9/deploy.prototxt"
-             DESTINATION_DIR "${CMAKE_CURRENT_LIST_DIR}/res/raw"
-             ID OPENCV_MOBILENET_SSD_CONFIG
-             STATUS res)
+# The Caffe MobileNet-SSD (mobilenet_iter_73000.caffemodel + deploy.prototxt) has been
+# replaced by a single-file ONNX model. The sample now loads "res/raw/mobilenet.onnx".
+if((DEFINED ENV{OPENCV_MOBILENET_SSD_ONNX_URL} OR DEFINED OPENCV_MOBILENET_SSD_ONNX_URL) AND OPENCV_MOBILENET_SSD_ONNX_HASH)
+  ocv_download(FILENAME "mobilenet.onnx"
+               HASH "${OPENCV_MOBILENET_SSD_ONNX_HASH}"
+               URL
+                 "${OPENCV_MOBILENET_SSD_ONNX_URL}"
+                 "$ENV{OPENCV_MOBILENET_SSD_ONNX_URL}"
+               DESTINATION_DIR "${CMAKE_CURRENT_SOURCE_DIR}/res/raw"
+               ID OPENCV_MOBILENET_SSD_ONNX
+               STATUS res)
+endif()
 
 add_android_project(${sample} "${CMAKE_CURRENT_SOURCE_DIR}" LIBRARY_DEPS "${OPENCV_ANDROID_LIB_DIR}" SDK_TARGET 11 "${ANDROID_SDK_TARGET}")
 if(TARGET ${sample})

samples/android/mobilenet-objdetect/src/org/opencv/samples/opencv_mobilenet/MainActivity.java

@@ -54,15 +54,19 @@ public class MainActivity extends CameraActivity implements CvCameraViewListener
         }
 
         //! [init_model_from_memory]
-        mModelBuffer = loadFileFromResource(R.raw.mobilenet_iter_73000);
-        mConfigBuffer = loadFileFromResource(R.raw.deploy);
-        if (mModelBuffer == null || mConfigBuffer == null) {
-            Log.e(TAG, "Failed to load model from resources");
-        } else
-            Log.i(TAG, "Model files loaded successfully");
+        // Load a single-file MobileNet-SSD ONNX model from res/raw/mobilenet.onnx.
+        // The resource is resolved by name at runtime so the sample still builds when the
+        // (optionally downloaded) model is absent; object detection is simply disabled then.
+        int modelResId = getResources().getIdentifier("mobilenet", "raw", getPackageName());
+        if (modelResId != 0)
+            mModelBuffer = loadFileFromResource(modelResId);
 
-        net = Dnn.readNet("caffe", mModelBuffer, mConfigBuffer);
-        Log.i(TAG, "Network loaded successfully");
+        if (mModelBuffer == null) {
+            Log.e(TAG, "MobileNet ONNX model (res/raw/mobilenet.onnx) not found - object detection disabled");
+        } else {
+            net = Dnn.readNetFromONNX(mModelBuffer);
+            Log.i(TAG, "Network loaded successfully");
+        }
         //! [init_model_from_memory]
 
         setContentView(R.layout.activity_main);
@@ -91,8 +95,8 @@ public class MainActivity extends CameraActivity implements CvCameraViewListener
         if (mOpenCvCameraView != null)
             mOpenCvCameraView.disableView();
 
-        mModelBuffer.release();
-        mConfigBuffer.release();
+        if (mModelBuffer != null)
+            mModelBuffer.release();
     }
 
     // Load a network.
@@ -107,7 +111,10 @@ public class MainActivity extends CameraActivity implements CvCameraViewListener
         final double MEAN_VAL = 127.5;
         final double THRESHOLD = 0.2;
 
-        // Get a new frame
+        if (net == null) {
+            return inputFrame.rgba();
+        }
+
         Log.d(TAG, "handle new frame!");
         Mat frame = inputFrame.rgba();
         Imgproc.cvtColor(frame, frame, Imgproc.COLOR_RGBA2RGB);
@@ -188,7 +195,6 @@ public class MainActivity extends CameraActivity implements CvCameraViewListener
             "motorbike", "person", "pottedplant",
             "sheep", "sofa", "train", "tvmonitor"};
 
-    private MatOfByte            mConfigBuffer;
     private MatOfByte            mModelBuffer;
     private Net                  net;
     private CameraBridgeViewBase mOpenCvCameraView;

samples/dnn/optical_flow.py

@@ -1,19 +1,14 @@
 #!/usr/bin/env python
 '''
-This sample using FlowNet v2 and RAFT model to calculate optical flow.
-
-FlowNet v2 Original Paper: https://arxiv.org/abs/1612.01925.
-FlowNet v2 Repo:  https://github.com/lmb-freiburg/flownet2.
-
-Download the converted .caffemodel model from https://drive.google.com/open?id=16qvE9VNmU39NttpZwZs81Ga8VYQJDaWZ
-and .prototxt from https://drive.google.com/file/d/1RyNIUsan1ZOh2hpYIH36A-jofAvJlT6a/view?usp=sharing.
-Otherwise download original model from https://lmb.informatik.uni-freiburg.de/resources/binaries/flownet2/flownet2-models.tar.gz,
-convert .h5 model to .caffemodel and modify original .prototxt using .prototxt from link above.
+This sample uses the RAFT model to calculate optical flow.
 
 RAFT Original Paper: https://arxiv.org/pdf/2003.12039.pdf
 RAFT Repo: https://github.com/princeton-vl/RAFT
 
 Download the .onnx model from here https://github.com/opencv/opencv_zoo/raw/281d232cd99cd920853106d853c440edd35eb442/models/optical_flow_estimation_raft/optical_flow_estimation_raft_2023aug.onnx.
+
+Note: the legacy FlowNet v2 Caffe pipeline (--proto/.caffemodel) has been removed together
+with the Caffe importer. Please provide a single ONNX model.
 '''
 
 import argparse
@@ -25,9 +20,8 @@ import cv2 as cv
 class OpticalFlow(object):
     def __init__(self, model, height, width, proto=""):
         if proto:
-            self.net = cv.dnn.readNetFromCaffe(proto, model)
-        else:
-            self.net = cv.dnn.readNet(model)
+            raise cv.error("Caffe support has been removed. Please provide a single ONNX model path (e.g. RAFT).")
+        self.net = cv.dnn.readNet(model)
         self.net.setPreferableBackend(cv.dnn.DNN_BACKEND_OPENCV)
         self.height = height
         self.width = width
@@ -75,41 +69,18 @@ if __name__ == '__main__':
     parser.add_argument('-input', '-i', required=True, help='Path to input video file. Skip this argument to capture frames from a camera.')
     parser.add_argument('--height', default=320, type=int, help='Input height')
     parser.add_argument('--width', default=448, type=int, help='Input width')
-    parser.add_argument('--proto', '-p', default='', help='Path to prototxt.')
-    parser.add_argument('--model', '-m', required=True, help='Path to model.')
+    parser.add_argument('--model', '-m', required=True, help='Path to a single ONNX model (e.g. RAFT).')
     args, _ = parser.parse_known_args()
 
     if not os.path.isfile(args.model):
         raise OSError("Model does not exist")
-    if args.proto and not os.path.isfile(args.proto):
-        raise OSError("Prototxt does not exist")
 
     winName = 'Calculation optical flow in OpenCV'
     cv.namedWindow(winName, cv.WINDOW_NORMAL)
     cap = cv.VideoCapture(args.input if args.input else 0)
     hasFrame, first_frame = cap.read()
 
-    if args.proto:
-        divisor = 64.
-        var = {}
-        var['ADAPTED_WIDTH'] = int(np.ceil(args.width/divisor) * divisor)
-        var['ADAPTED_HEIGHT'] = int(np.ceil(args.height/divisor) * divisor)
-        var['SCALE_WIDTH'] = args.width / float(var['ADAPTED_WIDTH'])
-        var['SCALE_HEIGHT'] = args.height / float(var['ADAPTED_HEIGHT'])
-
-        config = ''
-        proto = open(args.proto).readlines()
-        for line in proto:
-            for key, value in var.items():
-                tag = "$%s$" % key
-                line = line.replace(tag, str(value))
-            config += line
-
-        caffemodel = open(args.model, 'rb').read()
-
-        opt_flow = OpticalFlow(caffemodel, var['ADAPTED_HEIGHT'], var['ADAPTED_WIDTH'], bytearray(config.encode()))
-    else:
-        opt_flow = OpticalFlow(args.model, 360, 480)
+    opt_flow = OpticalFlow(args.model, 360, 480)
 
     while cv.waitKey(1) < 0:
         hasFrame, second_frame = cap.read()