User`s guide

Intensity to Binary Conversion
Note A single threshold value was unable to effectively threshold this
image due to its uneven lighting. For information on how to address this
problem, see “Correcting for Nonuniform Illumination” on page 6-11.
You have u sed the Relational O perato r block to conve rt an intensity image
to a bin ary i m age. For mo re in f ormation about this block, see t h e Re la tional
Operator block reference page in the Simulink docum entation. For another
example that uses this technique, see “Counting Objects in an Image” on page
6-3. For additional information, see “ Converting Between Image Types” in the
Image Processing Toolbox documentation.
Thresholding Intensity Images Using the
Autothreshold Block
In the previous topic, you used the Relatio nal Operator block to convert an
intensity image into a binary image. In this topic, you use the Autothreshold
blocktoaccomplishthesametask.UsetheAutothresholdblockwhenlighting
conditions vary and the threshold needs to change for each video frame.
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