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2015-02-20 10:59:57 -0500 commented question Mat to int[] and vice versa

oh thank you very much!!

2015-02-20 10:50:19 -0500 commented question Mat to int[] and vice versa

ok i will convert my display component to bitmap obj. How can i convert ;Mat to Bitmap and vice versa?

2015-02-20 10:34:01 -0500 commented question Mat to int[] and vice versa

because all my operations and all my program (that is long) works with int[] arrays. Now i have to compute this warp, i'm using OpenCV only for : findHomography and warpPerspective, so the decisions are two : or I modify ALL my program to work with Mat (ofc no ;) or i try this solution. So i don't have solutions... by the way images are 800x600 so they aren't so expensive

2015-02-20 10:19:25 -0500 asked a question Mat to int[] and vice versa

I'm completely new to this library, so apologize for my simple question. I'm using OpenCV library in Android. So Java.

Given a homographyMatrix :

    Mat srcMat, dstMat;
    int[] srcPixels, dstPixels;

    //... srcPixels filled with int values of pixels

   srcPixels conversion to srcMat

   Imgproc.warpPerspective(srcMat, dstMat, homographyMatrix, dstMat.size())

   dstMat conversion to dstPixels

this because i use int[] objects in order to display images.

Yes, i've already seen this question, but the answer is in c++ and does not really answer.

2015-02-19 11:50:56 -0500 asked a question Mat object from 1D array of integer

Hi all,

CONTEXT

I'm using OpenCV 2.4.10 library for Android, so i'm programming in Java. I have a int[640x480] array (let's call it pixelsArray). I have 4 indexes of the array that identify 4 values therefore 4 points .

PROBLEM

I need to convert pixelsArray into a Mat object in order to pass it to findHomography as source points.

QUESTION

Now what's the best practice? Is there any constructor of Mat that can do it automatically by passing a value that indicates the module to apply in order to fill properly the rows? Do I have to do it manually?

Thanks

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2015-02-19 08:40:35 -0500 commented answer FindHomography usage

What stands for rgb.cols? I have a int[] matrix (it's an array of int, rgb, values) so i have 4 indexes like 100, 1000, 2000, 3000. I've seen that findhomography wants point2f with x and y but i have only a single value. How can i overcome this? It's very frustrating that there isn't java documentation for this library....

2015-02-18 12:46:44 -0500 asked a question FindHomography usage

Hi all, i'm completely new, so i think it's very simple my problem.

Context

I'm using OpenCV library for Android, i'm capturing a video with my device (fixed in a position, not in movement), with a component of my program i can determine 4 point from the scene. So at the end I have a 640x480 int array , and i have 4 values (indexes) of the four point in the scene.

Problem

I want to do this kind of transformation:

transformation

Question

What do i have to do to make such a ("plane") transformation, in order to watch the scene from above? What i'm trying to saying is that: given 4 indexes of a rgb array that identify 4 real points of the scene, what do i have to pass to findHomography function? And after that, what do i have to do with Mat object to apply the change in real time?

I actually need detailed steps, because I'm completely new. Thanks a lot,.

Sorry i'm new to Computer Vision.