OpenCVLoader.initAsync() fails for the first few times
OpenCV 3.3.0 Android 7.1.1 Oneplus 5 I installed OpenCV 3.3.0 Manager arm64-v8a by adb to the phone. The OpenCVLoader.initAsync() operation always fails for the first few times, and succeeds finally. A...
View ArticleOpencv for Android with externalUVC camera
I am trying to use an external USB webcam with my dragonboard410C running Android 5.1 This is what I have been able to do so far. 1. Build OpneCV 3.0 Android on my Windows machine 2. Build and deploy...
View ArticleSetting the condition or threshold for detecting objects
Good day. I am currently developing an object recognition app in Android. I'm using feature matching technique using FAST, ORB, and Bruteforce Hamming as the feature extractor, descriptor extractor,...
View ArticleHow to get the timestamp of a frame when using opencv on Android
I am using opencv on Android. Is there a method to get the timestamp of the input frame when processing in: public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) { ... }
View ArticleHow to detect human body(shirt detection) with clear edges rather than...
Hi We have to create an android application in OpenCV to detect human upper half body i.e shirt detection. We need to get the structure of the shirt exactly with the edges. We are beginners to opencv.....
View ArticleHow do you compute abs() using UMat?
Hi My input is UMat 32FC1 and I'd like to compute abs() but I get a compile error "no matching function for call to 'abs'". my code works find for Mat, but I'd like to use the GPUs. I also tried...
View ArticleWhat is the java equivalent?
I'm trying to implement the below piece of code in JAVA; however, I cannot find a replacement for Vec3f. Any hint on it? Mat samples( img.rows * img.cols, 3, CV_32FC1 ); int index = 0; for( int y = 0;...
View ArticleOpenCv:Face-detection = java.lang.UnsatisfiedLinkError: Couldn't load...
my build.gradle : android { compileSdkVersion 25 buildToolsVersion "25.0.3" defaultConfig { applicationId "com.example.sspl.myopencv" minSdkVersion 19 targetSdkVersion 25 versionCode 1 versionName...
View ArticleANDROID Open FFmpeg frames
Hello, I have used OpenCV in Android to display frames from the camera, with "public Mat onCameraFrame(CvCameraViewFrame inputFrame) " method etc.... Now, I can receive frames from an url (udp://:8554...
View ArticleOpenCv Android only native
Hi, I am using the Android opencv sdk in my project, and everything is good but size. I know there are ways to build for diferent platforms, shrink size and so on, but my question is of different...
View ArticleCalcHist on java
Hello, I use calcHist function to learn colors (HSV) of sky images using svm. The learning process is coded in c++, I tested result and the precision is about 80%. Then I try to use the svm file in an...
View ArticleOpencv in android
Below is my jni source. Mat* diff; absdiff(*dilate, *gray, *diff); image = 255 - diff; And it's throw error invalid operands to binary expression ('int' and 'cv::Mat*') Can anyone help me resolve it.
View ArticleJava/Android access 4-Dim Mat planes
I am building an Android App with uses the DNN module. The output of the forward pass is a Mat with dims() = 4. Actually its the output of semantic segmentation (ENet Example) with 1x8x45x80....
View ArticleCascade Classifier - detectmultiscale does not return MatOfRect objects
I work on my android application as It mentioned [here](http://answers.opencv.org/question/173490/how-to-recognize-specific-objects/) . I have difficulties with class Cascade Classifier. I use HAAR...
View ArticleHow to use JavaCameraView in portrait mode?
Hello. How do I use the JavaCameraView from OpenCV in portrait mode? I found lots of [solutions](https://stackoverflow.com/a/30453132/963319) but they end of not working when I need to use the...
View ArticleAndroid OpenCV - Take Mat object from VideoView/SurfaceView
Hello! In my Android app there is a VideoView (I can also use a SurfaceView) where display a livestream from an udp url (it is the live stream from a GoPro and it work well). I need to take, when I...
View ArticleHow to use MSER correctly?
Hello. I want to use MSER to detect text. Something along [these lines](https://www.mathworks.com/help/vision/examples/automatically-detect-and-recognize-text-in-natural-images.html). So I wrote this...
View Articlecommon android project with opencv
Me and my friend are developing an image processing Android app, and we plan to use OpenCV for it. We opened a common project, controlled by GitHub. I know how to import the OpenCV module to the...
View ArticleIs it possible to share Java opencv code between Android and server?
I'm exploring OpenCV - I've been playing around with the Python API. I want to try building out an app for a fun idea I had that uses edge/contour detection. One way to do it is to have the mobile app...
View ArticleHow to draw contour around text string
Hi All, I am trying to implement simple contour around text: Init picture  I want to get the following: ![image...
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