PictureEffects Xojo Plugin |

# ConvolutionEffect.EdgeDetect Method

To detect edges of a picture use the EdgeDetect function. This filter will leave the Image black with colored edges. A Invert filter is often applied after a edge detect filter is applied.

EdgeDetect(
source as Picture,
mask as Picture) as Picture

#### Parameters

source
  The source picture to work with. This picture has to be 32 bits per pixel.
mask
  To limit the filtering to certain pixels then set a picture defining the mask to this parameter. Pass nil to this parameter if the filtering should not be limited to certain pixels.
  The mask picture must be a 32 bit picture and must be same size or larger than the src picture. If the mask picture is not 32 bits and at least the same size as the src picture then the function will fail and leave the result picture unchanged.

#### Returns

Picture
  If the filter was successful: A reference to the modified picture.
  If nil was returned then see the ErrorCode property to get hints for cause of the error.

#### Remarks

#### See Also

ConvolutionEffect Class