bird12358's profile - activity

It seems to work. But how could I activate the OpenCL part in the algorithm?

Compile opencv_contrib Hello, I work on ubuntu 16.04 and I try to compile a module in opencv_contrib. I have already i

Yes It was the problem. Thank you @berak

Yes I checked on the other computer is not readable , the videocapture are not opened. But what I don't understand is the path to the video is correct, so why the video are not open? Is there a codec problem on my computer? How can I check where the problem comes? In fact my question is not why there is a crash( it is obvious, opencv can't read the video) but more why Opencv can't read the video.

Hello,

I develop an application on my computer using Opencv. The application read Images and videos on windows 10 with Opencv 3.2.0 . On my computer both work properly.

I try to deploy the application on my other computer. So I take my exe file and the dll from Opencv and I put all this file on my computer. There is no Opencv install on it. When I try to execute my program, the images are readable but the video crash with that error:

opencv error assertion failed (scn == 3 scn == 4) in cvtcolor

Where that error could come?

Hello,

I work with Opencv on ubuntu. I get a simple camera. I get a preview on the image on guvcview and I have a full hd resolution from my camera. When I open a videocapture on opencv the resolution is reset to 640x480.

Why this append? Can I change the resolution of my device on opencv?

Can someone give me explainations about that?

Hello,

I works on weak classifier and i try to understand the implementation on OpenCV:

template<class feval=""> inline int predictOrdered( CascadeClassifierImpl& cascade, Ptr<featureevaluator> &_featureEvaluator, double& sum ) { int nstages = (int)cascade.data.stages.size(); int nodeOfs = 0, leafOfs = 0; FEval& featureEvaluator = (FEval&)_featureEvaluator; float cascadeLeaves = &cascade.data.leaves[0]; CascadeClassifierImpl::Data::DTreeNode* cascadeNodes = &cascade.data.nodes[0]; CascadeClassifierImpl::Data::DTree* cascadeWeaks = &cascade.data.classifiers[0]; CascadeClassifierImpl::Data::Stage* cascadeStages = &cascade.data.stages[0];

for( int si = 0; si < nstages; si++ )
{
    CascadeClassifierImpl::Data::Stage& stage = cascadeStages[si];
    int wi, ntrees = stage.ntrees;
    sum = 0;

    for( wi = 0; wi < ntrees; wi++ )
    {
        CascadeClassifierImpl::Data::DTree& weak = cascadeWeaks[stage.first + wi];
        int idx = 0, root = nodeOfs;

        do
        {
            CascadeClassifierImpl::Data::DTreeNode& node = cascadeNodes[root + idx];
            double val = featureEvaluator(node.featureIdx);
            idx = val < node.threshold ? node.left : node.right;
        }
        while( idx > 0 );
        sum += cascadeLeaves[leafOfs - idx];
        nodeOfs += weak.nodeCount;
        leafOfs += weak.nodeCount + 1;
    }
    if( sum < stage.threshold )
        return -si;
}
return 1;

}

Here is haar implémentation for facedetection. For what i understand, there are trees which contain nodes. A node is a part of a kernel which is apply to the image. A kernel ( a list of node ) is contained in a tree. In the previous code the program read all the trees and apply the node to the image. I don't understand why there are left and right part of the node? I try to find the explaination of this algorithm can't someone help me?

Hello,

I develop a native application on my shield tablet to get camera frame. I download the shield tutorial and I work on eclipse.

I get that erro:

    01-09 08:45:35.475: I/art(9536): Late-enabling -Xcheck:jni
01-09 08:45:35.559: D/AndroidRuntime(9536): Shutting down VM
01-09 08:45:35.560: E/AndroidRuntime(9536): FATAL EXCEPTION: main
01-09 08:45:35.560: E/AndroidRuntime(9536): Process: com.nvidia.NativeCamera, PID: 9536
01-09 08:45:35.560: E/AndroidRuntime(9536): java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "_ZN7android11BufferQueueC1ERKNS_2spINS_19IGraphicBufferAllocEEE" referenced by "/data/app/com.nvidia.NativeCamera-1/lib/arm/libnative_camera2.so"...
01-09 08:45:35.560: E/AndroidRuntime(9536):     at java.lang.Runtime.loadLibrary(Runtime.java:372)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at java.lang.System.loadLibrary(System.java:1076)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at com.nvidia.NativeCamera.NativeCamera.<clinit>(NativeCamera.java:23)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at java.lang.Class.newInstance(Native Method)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.app.Instrumentation.newActivity(Instrumentation.java:1067)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2359)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2518)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.app.ActivityThread.-wrap11(ActivityThread.java)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1345)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.os.Handler.dispatchMessage(Handler.java:104)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.os.Looper.loop(Looper.java:148)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at android.app.ActivityThread.main(ActivityThread.java:5457)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at java.lang.reflect.Method.invoke(Native Method)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
01-09 08:45:35.560: E/AndroidRuntime(9536):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

I don't really understand the reason of that error.

Can someone give me a hand?

Best regard.

Hello,

I would like to program a algorithm which estimates the extrinsec parameter. I don't found algorithm which estimate the rotation and the translation. I find easily algorithme to estimate the translation and the intrinsec parameter but I don't know how to find the rotation parameter.

I have this equation which link the XYZ position and the pixel:

u = au * ([r1 r2 r3][X Y Z] + tx) /([r7 r8 r9][X Y Z] + tz)

where the rotation R = [ r1 r2 r3; r4 r5 r6; r7 r8 r9]

Where could I find more information about the resolution of the algorithm?

Best regard.

Hello,

I had the same trouble with my webcam. I use unicap library which me information about my webcam:

Formats[1]:
    YUV 4:2:2 (YUYV) ( YUYV )
        FOURCC: YUYV
        size: 1280x1024x16
        size_count: 7
            640x480
            352x288
            320x240
            176x144
            160x120
            1280x800
            1280x1024

But the only result I can get, it is a gray scale images.

Do you achieve to get rgb images from your camera?