Out of Index Error when reading Image with OpenCV using Pointer - opencv

Question

I receive a weird out of range error when reading an 16-bit RGB image with openCV. The image has a resolution of 2700 x 2000. Outer rows and columns of the image are black.
I got the following code:
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>
using namespace cv;
using namespace std;
int main( int argc, char** argv )
{
// Create Mat Container and rowPtr
Mat image;
image = imread(argv[1], -1);
uint16_t* rowPtr;
// Read Image characteristics
int width = image.cols;
int height = image.rows;
int numChannels = image.channels();
if (image.isContinuous())
{
std::cout << "isContinuous!" << "\n";
width *= height;
height = 1;
}
// Double for loop, reading using pointers according to
// https://docs.opencv.org/2.4/doc/tutorials/core/how_to_scan_images/how_to_scan_images.html
for ( uint32_t y = 0; y < height; ++y )
{
rowPtr = image.ptr<uint16_t>(y);
for ( uint32_t x = 0; x < width; ++x )
{
const uint32_t idx = x + y * width;
// Quick Debug
if (idx > 2704713)
{
std::cout << "height : " << height << "\n";
std::cout << "width : " << width << "\n";
std::cout << "row : " << y << "\n";
std::cout << "col : " << x << "\n";
std::cout << "idx : " << idx << "\n";
std::cout << "B: " << rowPtr[numChannels * idx + 0] << "\n";
std::cout << "G: " << rowPtr[numChannels * idx + 1] << "\n";
std::cout << "R: " << rowPtr[numChannels * idx + 2] << "\n"; //The error occurs here!
}
}
}
namedWindow( "Display window", WINDOW_AUTOSIZE ); // Create a window for display.
imshow( "Display window", image ); // Show our image inside it.
waitKey(0); // Wait for a keystroke in the window
return 0;
}
The output of running the code is:
isContinuous!
height : 1
width : 5400000
row : 0
col : 2704714
idx : 2704714
B: 0
G: 0
So, the segmentation fault happens, when the value for R should be read, at Pixel No. 2,704,715.
This code runs without problems for images that don't exhibit large black borders. So I thought that openCV's imread might crop such images internally, leading to such an error?