jefferson-sep's profile - activity

Thanks, but "Function 'Mat_to_vector_Point2f' could not be resolved", so what i need include on my .cpp ? Or i need implement this function ? @Yolteotl

I am doing a project in Java with Android jni C ++. I have a function in C ++ with the following parameters:

C ++ function:

void rectify (vector <Point2f> & corners, Mat & img) {...}

In JAVA, call would be:

Mat image = Highgui.imread("img.png");
List <MatOfPoint> cornners =  new ArrayList<MatOfPoint>();;
Point b = new Point (real_x2, real_y2);
MatOfPoint ma = new MatOfPoint (b);
cornners.add(ma);
rectfy(image.getNativeObjAddr(), cornners)

public native "??" rectfy(long mat, "??" matofpoint);

With that, I wonder how will the function C ++ jni:

JNIEXPORT ?? JNICALL Java_ImageProcessingActivity_rectfy (JNIEnv * jobject, ?? cornners, inputMatAddress jlong)

Hello, i have a code OpenCV C++ that does some transformations at images. I would like to know if you can make an Android project that uses the camera to take a picture and then call the code I already have (in C ++) to perform the necessary transformations in the picture, after that, return the transformed image or save this image on phone.

Ps: This passage image can be directly or saving to SD card and open.

Can I use the code in C ++ I already own?

Hello, I have a project in OpenCV C ++, and would like to pass it to Android, create an application with it. I wonder if you can use the code that I have in C ++, or need to convert it to Java? Thanks !!

Oh, that explains why I could only detect white or black -- ' Thanks

Thanks again Theodore! I'm using the follow code with image in example, but the output is just a black image. There's something wrong?

  Mat source = imread("chessOrange.png",1);
imshow("source", source);
Mat mask;
cv::Scalar lowerb = cv::Scalar(250, 125, 38);
cv::Scalar upperb = cv::Scalar(255, 129, 42);
cv::inRange(source, lowerb, upperb, mask);

imshow("mask", mask);

Hi, I'm trying to detect and map all pixels of a certain color. Then leave the pixels of that color. I have this image:

And I need to find the pixels orange (255,127,39). Then leave only the pixels of orange, like this:

I know the OpenCV has this function:

cv::findNonZero(src, vector_white_pixels);

but do not know if there is a similar function to specify color with pixels

Thanks for any help.

1. Have you checked that the file exists in the designated directory?
2. You already performed some opencv application?

1. Have you checked that the file exists in the designated directory?
2. You already performed some opencv application?

Theodore, Thank you for your cooperation! I will try to adapt the code to work with images of this type: http://i.imgur.com/Z6KSOgU.jpg

Yes, I'm trying it =)

Thanks for the answer, but in this example, it inserts the coordinates of the points that form the corners. I meant to find automatically. But still helped because lack only able to determine the corners and I think I know how to do this, Tks!

Hello, I'm trying to perform a transformation, or perspective correction, on the image with the chess board features as follows:

However, already tried in several places, including in the book Learning OpenCV and have not found a way to do this. If anyone can help me with this I thank you!

Thanks for the help!!!

I am a beginner to opencv / C ++ and would like your help with a problem that seems simple. As an example, I have this image:

... And would disregard the background, which will always be white, and the image is always black and white, leaving only the cloud to be able to count three things:

1. The number of pixels of the figure (cloud only, disregarding the background).
2. The number of white pixels. (cloud only)
3. The number of black pixels. (cloud only)

I know that to achieve 2, with a subtraction with it the 3rd.

Thanks!

Hello, I am trying to get the perspective transformation of the image, to get the next result looks like this:

The following steps in the tutorial that I'm following are: 1.Get the edge map. 2.Detect lines with Hough transform. 3.Get the corners by finding intersections between lines. 4.Check if the approximate polygonal curve has 4 vertices. 5.Determine top-left, bottom-left, top-right, and bottom-right corner. 6.Apply the perspective transformation.

The transformation work only with the image used in the tutorial. For while trying to retrieve the edges and points of interception, the results are these:

And I can only make the transformation priate the image has the 4 pieces, forming a quadrilateral object.

I am starting in OpenCV / C ++ and any help will be greatly appreciated. Thank U.

Tutorial link: http://opencv-code.com/tutorials/auto...