/// <summary>
/// Open AVI file.
/// </summary>
///
/// <param name="fileName">AVI file name to open.</param>
///
/// <remarks><para>The method opens a video file and prepares the stream and decoder for
/// reading video frames with the help of <see cref="GetNextFrame"/> method.</para>
/// </remarks>
///
/// <exception cref="ApplicationException">Failure of opening video files (the exception message
/// specifies the issues).</exception>
///
public void Open(string fileName)
{
// close previous file
Close();
lock (this)
{
// open AVI file
if (Win32.AVIFileOpen(out file, fileName, Win32.OpenFileMode.ShareDenyWrite, IntPtr.Zero) != 0)
{
throw new ApplicationException("Failed opening AVI file");
}
// get first video stream
if (Win32.AVIFileGetStream(file, out stream, Win32.mmioFOURCC("vids"), 0) != 0)
{
throw new ApplicationException("Failed getting video stream");
}
// get stream info
Win32.AVISTREAMINFO info = new Win32.AVISTREAMINFO();
Win32.AVIStreamInfo(stream, ref info, Marshal.SizeOf(info));
width = info.rectFrame.right;
height = info.rectFrame.bottom;
position = info.start;
start = info.start;
length = info.length;
rate = (float)info.rate / (float)info.scale;
codec = Win32.decode_mmioFOURCC(info.handler);
// prepare decompressor
Win32.BITMAPINFOHEADER bitmapInfoHeader = new Win32.BITMAPINFOHEADER();
bitmapInfoHeader.size = Marshal.SizeOf(bitmapInfoHeader.GetType());
bitmapInfoHeader.width = width;
bitmapInfoHeader.height = height;
bitmapInfoHeader.planes = 1;
bitmapInfoHeader.bitCount = 24;
bitmapInfoHeader.compression = 0; // BI_RGB
// get frame object
if ((getFrame = Win32.AVIStreamGetFrameOpen(stream, ref bitmapInfoHeader)) == IntPtr.Zero)
{
bitmapInfoHeader.height = -height;
if ((getFrame = Win32.AVIStreamGetFrameOpen(stream, ref bitmapInfoHeader)) == IntPtr.Zero)
{
throw new ApplicationException("Failed initializing decompressor");
}
}
}
}
/// <summary>
/// Create new AVI file and open it for writing.
/// </summary>
///
/// <param name="fileName">AVI file name to create.</param>
/// <param name="width">Video width.</param>
/// <param name="height">Video height.</param>
///
/// <remarks><para>The method opens (creates) a video files, configure video codec and prepares
/// the stream for saving video frames with a help of <see cref="AddFrame"/> method.</para></remarks>
///
/// <exception cref="ApplicationException">Failure of opening video files (the exception message
/// specifies the issues).</exception>
///
public void Open(string fileName, int width, int height)
{
// close previous file
Close();
lock (this)
{
// calculate stride
stride = width * 3;
if ((stride % 4) != 0)
{
stride += (4 - stride % 4);
}
// create new file
if (Win32.AVIFileOpen(out file, fileName, Win32.OpenFileMode.Create | Win32.OpenFileMode.Write, IntPtr.Zero) != 0)
{
throw new ApplicationException("Failed opening file");
}
this.width = width;
this.height = height;
// describe new stream
Win32.AVISTREAMINFO info = new Win32.AVISTREAMINFO();
info.type = Win32.mmioFOURCC("vids");
info.handler = Win32.mmioFOURCC(codec);
info.scale = 1;
info.rate = rate;
info.suggestedBufferSize = stride * height;
// create stream
if (Win32.AVIFileCreateStream(file, out stream, ref info) != 0)
{
throw new ApplicationException("Failed creating stream");
}
// describe compression options
Win32.AVICOMPRESSOPTIONS options = new Win32.AVICOMPRESSOPTIONS();
options.handler = Win32.mmioFOURCC(codec);
options.quality = quality;
// uncomment if video settings dialog is required to show
// Win32.AVISaveOptions( stream, ref options );
// create compressed stream
if (Win32.AVIMakeCompressedStream(out streamCompressed, stream, ref options, IntPtr.Zero) != 0)
{
throw new ApplicationException("Failed creating compressed stream");
}
// describe frame format
Win32.BITMAPINFOHEADER bitmapInfoHeader = new Win32.BITMAPINFOHEADER();
bitmapInfoHeader.size = Marshal.SizeOf(bitmapInfoHeader.GetType());
bitmapInfoHeader.width = width;
bitmapInfoHeader.height = height;
bitmapInfoHeader.planes = 1;
bitmapInfoHeader.bitCount = 24;
bitmapInfoHeader.sizeImage = 0;
bitmapInfoHeader.compression = 0; // BI_RGB
// set frame format
if (Win32.AVIStreamSetFormat(streamCompressed, 0, ref bitmapInfoHeader, Marshal.SizeOf(bitmapInfoHeader.GetType())) != 0)
{
throw new ApplicationException("Failed creating compressed stream");
}
// alloc unmanaged memory for frame
buffer = Marshal.AllocHGlobal(stride * height);
if (buffer == IntPtr.Zero)
{
throw new ApplicationException("Insufficient memory for internal buffer");
}
position = 0;
}
}
