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Discontinuous Mat (Using Mat.data = address instead of copyTo)

Hello, I receive image sections frame-by-frame from moving images on a conveyor belt.

Using ROIs I piece the frame-by-frame images together to make one image. This works fine.

Except I have to use copyTo instead of just moving pointers. This makes sense as the original Mat would become discontinuous. Except Mat supports discontinuous, so I'm wondering if there is a better way.

Here's what I do now:

In constructor:

m_InData = Mat(m_h, m_w, CV_8UC4);
m_ScrollingBuffer = Mat(m_h*m_NumBufPerScrollingBuf, m_w, CV_8UC4);

for (int i=0; i<m_NumBufPerScrollingBuf;i++)
    m_ScrollingBufferROI.push_back(Mat(m_ScrollingBuffer, Range(i*m_h, (i+1)*m_h), Range(0,m_w)));

And at Run-Time, after I get a frame:

GetImageAddress(&address);
m_InData.data = address;

for (int i=1; i<=m_NumBufPerScrollingBuf-1; i++)
    m_ScrollingBufferROI[i].copyTo(m_ScrollingBufferROI[i-1]);
m_InData.copyTo(m_ScrollingBufferROI[m_NumBufPerScrollingBuf-1]);

But I'd like to something more elegant like:

for (int i=1; i<=m_NumBufPerScrollingBuf-1; i++)
    m_ScrollingBufferROI[i-1].data = m_ScrollingBufferROI[i].data;
m_ScrollingBufferROI[m_NumBufPerScrollingBuf-1].data = address;

But the above doesn't work (I suspect because of the non-continuous nature.)

Suggestions?

Thanks and sorry if a similar/duplicate question shows up.

Gunter