IplImage Pixel Access JavaCV

Question

I'm trying to access Pixel by Pixel of an IplImage. Im using Java and Processing, and sometimes I need to access pixel by pixel. I've done this so far, but I don't know what's wrong: ``` public IplImage PImageToIplImage(PImage imageSrc) { IplImage imageDst; if(imageSrc.format==RGB) { imageDst = IplImage.create(imageSrc.width, imageSrc.height, IPL_DEPTH_8U, 3); ByteBuffer imagePixels=imageDst.getByteBuffer(); int locPImage, locIplImage, x, y; for(y=0; y<imageSrc.height; y++) for(x=0; x<imageSrc.width; x++) { locPImage = x + y * width; locIplImage=y*imageDst.widthStep()+3*x; imagePixels.put(locIplImage+2, (byte)(red(imageSrc.pixels[locPImage]))); imagePixels.put(locIplImage+1, (byte)(green(imageSrc.pixels[locPImage]))); imagePixels.put(locIplImage, (byte)(blue(imageSrc.pixels[locPImage]))); } } } ``` After Karlphilip sugestion, I came to this, still doens't work. When I try to show, it gives me a nullPointer exception: ``` imageDst = IplImage.create(imageSrc.width, imageSrc.height, IPL_…

Accepted Answer

The fastest way to iterate over each pixel in JavaCV is:

```
ByteBuffer buffer = image.getByteBuffer();

for(int y = 0; y < image.height(); y++) {
    for(int x = 0; x < image.width(); x++) {
        int index = y * image.widthStep() + x * image.nChannels();

// Used to read the pixel value - the 0xFF is needed to cast from
        // an unsigned byte to an int.
        int value = buffer.get(index) & 0xFF;

// Sets the pixel to a value (greyscale).
        buffer.put(index, value);

// Sets the pixel to a value (RGB, stored in BGR order).
        buffer.put(index, blue);
        buffer.put(index + 1, green);
        buffer.put(index + 2, red);
    }
}
```

IplImage Pixel Access JavaCV

Solution

Problem