public void GetBitmapHeader()
{
IntPtr p = VfwApi.AVIStreamGetFrame(pgf_, 0);
if (p == IntPtr.Zero)
{
throw new VfwException("先頭のフレーム取得に失敗しました。");
}
byte[] header = new byte[40];
Marshal.Copy(p, header, 0, header.Length);
MemoryStream ms = new MemoryStream(header);
BinaryReader reader = new BinaryReader(ms);
reader.ReadInt32();
width_ = reader.ReadInt32();
height_ = reader.ReadInt32();
if (height_ < 0)
{
is_flip_ = false;
height_ = -height_;
}
reader.ReadInt16();
bit_count_ = reader.ReadUInt16();
if (bit_count_ != 24 && bit_count_ != 32)
{
throw new VfwException("24ビットと32ビットカラー以外には対応していません。");
}
ms.Close();
}
public Bitmap GetBitmap(int frame_number)
{
IntPtr p = VfwApi.AVIStreamGetFrame(pgf_, frame_start_ + frame_number);
if (p == IntPtr.Zero)
{
throw new VfwException("AVIStreamGetFrame", 0);
}
p = new IntPtr(p.ToInt32() + 40);
int stride = (width_ * bit_count_ / 8 + 3) & ~3;
byte[] buffer = new byte[stride * height_ + 54];
Marshal.Copy(p, buffer, 0, buffer.Length);
GCHandle handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
Bitmap bitmap = new Bitmap(width_, height_, stride, BitCountToPixelFormat(bit_count_), handle.AddrOfPinnedObject());
handle.Free();
if (is_flip_)
{
bitmap.RotateFlip(RotateFlipType.RotateNoneFlipY);
}
return(bitmap);
}