EVP Toolbox
	
	video_write_frame - write a frame to a opened video file
	
Calling Sequence
	video_read_frame( img, opened_handle );

Parameters
	* opened_handle: a return handle from video_open_w.
	* img : a RGB image NxMx3

Description
	We use FFmpeg. FFmpeg is a complete solution to record, convert and stream audio and video. It includes libavcodec, the leading audio/video codec library. FFmpeg is a charming library. Now we can open almost all type of video file under both Linux and windows. For more information, go to  http://ffmpeg.mplayerhq.hu/
	For each time, you write a frame, the file pointor is moved to next frame.

Examples
	Here is a example for converting video format:
	in = video_open( 'ww.mpg');
	out = video_open_w ('out.swf', 400000, 352, 288, 25);
	[frame, num ] = video_info(in)

	for i=1:num
	 im = video_read_frame(in);
	 video_write_frame( im, out );
	end
	
	video_close_w( out );
	video_close(in);