private void checkBoxPrune_CheckedChanged(object sender, EventArgs e)
{
if (_faceDetect != null)
{
_faceDetect.SetPrune(checkBoxPrune.Checked);
}
// recompute the detected rectangles
if (listBoxDetectedRect.Items.Count > 0)
{
listBoxDetectedRect.SelectedIndex = 0;
}
else
{
_fImgDirty = true;
RenderImage(CreateGraphics());
}
}