how to use opencv4android pca to train svm model?
classification problem is static hand gesture recognition for android smart phones. my problem is I am new with openCV so how to use PCA to get feature vectors?so i can use these vectors to train my...
View ArticleBuilding android java bindings
Hi, I'm trying to build a jar file containing the java bindings. I've tried git clone git://github.com/Itseez/opencv.git cd opencv mkdir build cd build cmake -DBUILD_SHARED_LIBS=OFF .. make -j8 which...
View ArticleUsing OpenCV on android without preview
Hi, I went through a couple of the provided OpenCV examples provided here: https://github.com/Itseez/opencv/tree/master/samples/android It seems, all of them actually build an activity that implements...
View ArticleHow to use native camera with Android?
Hi, I'm trying to use the native camera with android (tried on 6.0.1 and 5.1.1) mCamera = new VideoCapture(mCameraId); if (!mCamera.isOpened()) { Log.d(TAG, "Failed to open camera " + mCameraId); }...
View ArticleHow I detect marker using OpenCV for android
hi, recently I learned OpenCV for android to make the marker-based augmented reality applications, I found the book Android Application Programming with OpenCV 3 and there are cases where the...
View ArticleWhen Android studio compatible opencv version will be released?
Hi, I just want to know that when Android studio compatible opencv version will be released?
View ArticleAndroid ORB not showing both image and video
Hey guys! I'm working on an Android application that should get an input image from my database and compare it to a video stream from my phone's camera. I've tried to open just the image and it's...
View ArticleDewarp images taken using digital camera
I want to dewarp slightly cylindrical documents photographed with digital camera (like as in android devices). Is there any opencv algorithm to do the job. I have gone through some research papers...
View Articlescreen portrait face isn't detected
Hi all, I got a bug. If I have 1 screen landscape face is detected, but screen portrait not detected. My code: public class JavaCameraView extends CameraBridgeViewBase implements PreviewCallback {...
View ArticleFind rectangle from image in android?
hello, i want to find four black cornered rectangle from below image how to find those four border rectangle from this image? i have tried with this code Mat...
View ArticleORB save video frame if object is detected
I'm working on an Android app that uses ORB algorithm to find an object in the video stream received from the camera. What I'm trying to do is save the video frame where the object appears. I don't...
View ArticleonCameraFrame returns mat with bad resolution and small.
I am a beginner and trying to show camera preview in JavaCameraView with CvCameraViewListener2, I get very bad resolution, and not managing to get size of preview to be full screen. My...
View ArticleHot to convert a Mat object to byte[] data object in "onPreviewFrame" and...
In my android app, I am trying to take frames in "onPreviewFrame" and convert them to Mat object so i can do on them some image processing, but i don't know how to convert them back to byte[] type and...
View ArticleMeanshift is not an option in android native development.
I'm trying to develop an app that uses meanshift to track an object. I got the code working in python and decided to integrate it into the android app instead of sending the data to a server for...
View Article[Android] Get camera frame but show no preview
Hi guys, I'd like to process frames from front camera on my Android device. But I've seen that if I don't have **JavaCameraView** (it's defined in layout XML file) visible, ***OnCameraFrame()*** method...
View ArticleWhen I use 'cvtColor' with JNI, Console says: Fatal signal 11 (SIGSEGV), code...
Recently, I try using OpenCV at Android.I write a native method，and use it at java. JNIEXPORT jintArray JNICALL Java_yu_myself_opencv_jni_OpenCVHelper_canny( JNIEnv *env, jclass obj, jintArray buf, int...
View ArticleAndroid - selecting ROI of image
Hi all, May i ask if i want to have a "pop-up window" for the app user on selecting ROI, how can i achieve that in Android? And also, how can i selecting ROI using opencv? Thanks a lot
View ArticleAndroid text detection/recognition
I am trying to do text detection on Android using OpenCV4Android 3.1.0, but I can't seem to find the "text" module and the only example is in C++. I'm assuming the text module is still experimental and...
View ArticleHow to add two different OpenCV libs in Android Studio?
I'm in the strange need of using both 2.4.11 (old HOG CascadeClassifier) and 3.1.0 (new Kalman filter) OpenCV libraries in Android Studio. I've got the new 3.1.0 working but when I add the new module...
View Articleandroid split camera preview with opencv like cardboard applications
I have a camera preview on my application but i need to split this view to two views like cardborad and samsung gear vr applications but with openCV library to make some filters and image processing...
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