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grabSeq ( integer Output, integer Frames, integer FrameWin [, integer Delay ] )

Use this function to perform a sequential frame averaging and to capture several averaged frames as an image sequence. This function is typically used for the noise reduction on a real-time video. The format and size of the sequence captured depends on the video device settings.

An integer between 1 and 116 specifying the number of the workspace frame into which the sequence will be placed. Values in the range of 100-116 correspond to hidden frames.  
A positive integer specifying the amount of video frames to be captured into the sequence.  
A number of consecutive frames used for the sequential averaging. For better performance this parameter must be a power of 2.  
A positive integer specifying the delay (in milliseconds) between consecutive video frames to be captured into the sequence. If this parameter is omitted or if the video device frame rate is lower than the rate corresponding to the specified delay time, the function will use the fastest frame rate possible for the current video device adjusting the actual delay time accordingly.  
Error flags

The flag set if successful.  
The flag set if failed.  
The flag set if timeout occurred.  

The following operator will capture a sequence of 64 video frames with a 4-frames averaging window:  
grabSeqAvrg(1, 64, 4)  

Before generating the first frame for the sequence, the function must collect a number of video frames to be used in the averaging cycle. Therefore, some delay should be expected after the function is called.