Can't load image into OpenGL texture if it is larger than 256x128

Question

I am trying to load a jpeg image into a texture which I will use for volume rendering. However, the image fails to load (only white rectangle shown) whenever I try to load a jpeg larger than 256x128 pixels.

I am using OpenCV to convert the jpeg into raw values. This sounds like overkill, but I had OpenCV already. I am open to using another library

My code may seem strange, but it is because I am using luminance values, but also using an alpha value. As a result, I am taking the luminance value and using it across the RGBA channels for now.

This code worked when I used raw luminance data. But now, I am just trying to load a single jpeg image. (It works when my image is 256x128, but fails if it is bigger)

My texture loading code:

unsigned char* chRGBABuffer = new unsigned char[IMAGEWIDTH * IMAGEHEIGHT * IMAGECOUNT * 4];

//Only create 1 3D texture now
glGenTextures(1, (GLuint*)&textureID3D);

// Set the properties of the texture.
glBindTexture(GL_TEXTURE_3D, textureID3D);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

// Convert the data to RGBA data.
// Here we are simply putting the same value to R, G, B and A channels.
// This can be changed depending on the source data
// Usually for raw data, the alpha value will
// be constructed by a threshold value given by the user
for (int i = 0; i < IMAGECOUNT; ++i)
{
    cv::Mat image;
    image = cv::imread(filename, CV_LOAD_IMAGE_GRAYSCALE); 
    unsigned char * chBuffer = image.data; 

    if (!image.data)                              // Check for invalid input
    {
        fprintf(stderr, "Could not open or find image\n");
        return -1;
    }

    for (int nIndx = 0; nIndx < IMAGEWIDTH * IMAGEHEIGHT; ++nIndx)
    {
        chRGBABuffer[nIndx * 4] = chBuffer[nIndx];
        chRGBABuffer[nIndx * 4 + 1] = chBuffer[nIndx];
        chRGBABuffer[nIndx * 4 + 2] = chBuffer[nIndx];
        chRGBABuffer[nIndx * 4 + 3] = chBuffer[nIndx];
    }
}

glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA, IMAGEWIDTH, IMAGEHEIGHT, IMAGECOUNT, 0,
    GL_RGBA, GL_UNSIGNED_BYTE, (GLvoid *)chRGBABuffer);
glBindTexture(GL_TEXTURE_3D, 0);

Answer 1

Probably you're simply running out of texture memory. Volumetric images are memory hogs and only few OpenGL implementations are capable of swapping in portions of a 3D texture on demand (at a significant performance drop penality).