F-IN-BOX .NET Edition: How To Grab Frames From A Flash Movie
One customer wrote me:
Why GetBitmap method consums so much processor time.
It’s 720×576 25fps simple movie with 40-60% processor time.
I’m making a call to GetBitmap without any further processing.
Actually, GetBitmap is not a good way when you need to grab frames from a movie quickly. So, what is the best way?
Use f_in_box__control, set TransparentMode = true, then handle OnFlashPaint event, for example:
[DllImport("Kernel32.dll", EntryPoint = "RtlMoveMemory")]
private static extern void CopyMemory(IntPtr Destination, IntPtr Source, int Length);
private void flashControl1_OnFlashPaint(object sender, IntPtr pPixelPointer)
{
if (videoOut != null)
{
BitmapData bmd = videoOut.VideoBitmap.LockBits(new Rectangle(0, 0, 720, 576), ImageLockMode.WriteOnly, PixelFormat.Format32bppArgb);
int StrideSize = 720 * 4;
for (int i = 0; i < 576; i++)
{
IntPtr s = new IntPtr(pPixelPointer.ToInt32()+StrideSize * i);
IntPtr d = new IntPtr(bmd.Scan0.ToInt32() + (StrideSize * (575 - i)));
CopyMemory(d, s, StrideSize);
}
videoOut.PixelPointer = bmd.Scan0;
videoOut.VideoBitmap.UnlockBits(bmd);
}
}
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