User`s guide

Logging Image Data to Disk

vid.DiskLoggerFrameCount

ans =

Note Becauseittakeslongertowriteframestoadiskfilethantomemory,

the value of the

DiskLoggerFrameCount property can lag behind the value

of the

FramesAvailable property, which specifies the number o f frames

logged to memory.

To verify that a dis k file was created, go to the directory in which the log

file resides and make sure it exis ts. The

exist function returns 2 if the

file exists.

if(exist(my_log)==2)

disp('AVI file create d.')

6 ClosetheAVIfileobject— Close the AVI file to make it available

outside the MATLAB environment. Closing the AVI file object ensures that

theloggeddataiswrittentothediskfile. Besuretousethevalueofthe

video input object

DiskLogger property, vid .DiskLogger, to reference the

AV I file object, not the original variable,

aviobj, returned by the av ifil e

function.

aviobj = close(vid.Di skLogger);

Use the original variable, aviobj, as the return value when closing an

AVI file object.

7 Clean up — Always rem ove image acquisition objects from mem ory, and

the variables that re ference them, when you n o longer need them.

delete(vid)

clear vid

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