title: __memcpy_ssse3() segmentation fault
body: <p>i'm working with Opencv, trying to copy some frame that captured from web camera. when copying the frame, i'm getting segmentation fault in <code>__memcpy_ssse3()</code>, line 160 or 1675. </p>
  
  <p>gdb shows:</p>
  
  <blockquote>
    <p>0  __memmove_ssse3 () at
    ../sysdeps/i386/i686/multiarch/memcpy-ssse3.S:1675</p>
    
    <p>1  0xb75ec6d0 in cv::Mat::copyTo (this=0xbfca3450, _dst=...) at
    /home/david/opencv/OpenCV-2.4.2/modules/core/src/copy.cpp:181</p>
    
    <p>2  0xb75984f6 in cv::Mat::Mat (this=0xbfca358c, img=0xb1300c90,
    copyData=true) at
    /home/david/opencv/OpenCV-2.4.2/modules/core/src/matrix.cpp:510</p>
  </blockquote>
  
  <p>The function that calls it is <code>cv::MAt::Mat(IplImg *I, bool copy)</code>.</p>
  
  <p>When I'm opening USB camera or file, everything is perfect, but when trying to read the video stream from webcam, via IP, it crashes after a minute.</p>
  
  <p>I'v try to build ffmpeg and opencv without ssse3 support, and my application compiled with <code>-mno-seee3</code> flag too. </p>
  
  <p>Opencv vesion is 2.4.2, but the problem exists in 2.3.1 too.
  ffmpeg version is 11.1, same problem in 8.X.
  gcc version is 4.6.3, Ubuntu's branch. 
  The processor is Intel core2.</p>
  
  <p>Any hints?</p>