Fixed, briefly instead of using qt based QGLWidget::paintEvent, I used directly OpenGL to draw my frames.
sample would be:
Qt Code:
  1. ::initializeGL(){
  2. glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  3. }
  4.  
  5. ::paintGL(){
  6. glRasterPos2i(0,0);
  7. glDrawPixels(pImg->width(), pImg->height(), GL_BGRA, GL_UNSIGNED_BYTE, pImg->bits());
  8. glPixelZoom(1.0,-1.0);
  9. glFlush();
  10. }
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For more interesting way google for "OpenGL programming guide (AKA OpenGL RedBook)"
salutations a tous qui m'aider!!
firas